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PsychologyBook.pdf
Psychology: The Human Puzzle
Guy R. Lefrançois University of Alberta
Guy R. Lefrançois Psychology: The Human Puzzle
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ISBN-10: 1-9359662-4-3
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To Elizabeth, Liam, Zachary, Nathan, and Michael, who are still finding new pieces of the puzzle for me.
Brief Contents
Chapter 1: The Science of Psychology . . . . . . . . . . . . . . . . . . . .1
Chapter 2: The Brain and Consciousness . . . . . . . . . . . . . . . .31
Chapter 3: Sensation and Perception . . . . . . . . . . . . . . . . . . . .65
Chapter 4: Learning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103
Chapter 5: Memory and Intelligence . . . . . . . . . . . . . . . . . . .135
Chapter 6: Motivation and Emotion . . . . . . . . . . . . . . . . . . . .169
Chapter 7: Human Development . . . . . . . . . . . . . . . . . . . . . .207
Chapter 8: Personality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247
Chapter 9: Psychological Disorders and Therapies . . . . . . .279
Chapter 10: Social Psychology . . . . . . . . . . . . . . . . . . . . . . . .315
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .349
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .373
Photo Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .409
Contents
About the Author xix Preface xxi Acknowledgments xxiii
chapter 1 The Science of Psychology 1
1.1 What Is Psychology? 3 What Psychologists Do 3
Clinical Psychologists 4 Counseling Psychologists 4 Industrial/Organizational Psychologists 4 School Psychologists 4 Educational Psychologists 5 Developmental Psychologists 5 Experimental Psychologists 5 Other Divisions 5
1.2 The Beginnings of Psychology 6 Recent Origins of Psychology 7
Structuralism 8 Functionalism 8 Behaviorism 8 Psychodynamic Theory 9 Cognitivism 9 Humanism 9 Other Orientations 10
1.3 Principles of Science 10 The Scientific Method 11
CONTENTS
1.4 Sources of Psychological Information 12 Descriptive Research 12
Naturalistic and Nonnaturalistic Observation 12 Case Studies 13 Surveys 14 Correlational Research 15
Experiments 17 Experimental and Control Groups 17
Ex Post Facto Studies 19 1.5 Cautions in Interpreting Psychological Research 20
Experimenter Bias 20 Subject Bias 22 Sampling Bias 22 Other Problems of Psychological Research 24
Research Ethics 24 Avoiding the Pitfalls 25
1.6 Philosophical Issues and Psychological Controversy 25
1.7 Psychology’s Relevance 26
1.8 This Book 27
Main Points 28 Study Terms 29
chapter 2 The Brain and Consciousness 31
2.1 Evolution 33 Early Homo Sapiens 33
Brains, Language, and Thinking 35 Evolution and the Nervous System 36
2.2 The Neuron 38 Neural Transmission 39
Dopamine 41 Norepinephrine 41 Acetylcholine 42 Serotonin 42
2.3 Organization of the Nervous System 42 The Endocrine System 44
2.4 The Brain 44 Studying Brain Functions 44
Brain Ablations 45 Brain Stimulation 45 Brain Imaging 46
CONTENTS
Structures of the Brain 46 Hindbrain 48 The Midbrain 49 The Forebrain 49 The Hemispheres 50
2.5 Biology and Behavior 51 Consciousness 53
2.6 Sleep 54 Circadian Rhythms 54 Stages of Sleep 54 Why We Sleep 56 Dreams 58
Why We Dream 58 2.7 Hypnosis 59
Some Facts 60 Is Hypnosis a Different State of Consciousness? 60 Applications of Hypnosis 61
2.8 Drugs and Consciousness 61
Main Points 62 Study Terms 63
chapter 3 Sensation and Perception 65
3.1 Sensation and Perception 67 Functions of the Senses 67
3.2 Vision 69 Structure of the Eye 69 Eye and Brain 71 Light Waves and Vision 72
Wavelength 73 Amplitude 74 Complexity and Color Purity 74
Color Vision 74 Trichromatic Theory: Young-Helmholtz 75 Opponent Process Theory: Hering 76
Vision in Low Light 76 Characteristics of Visual Perception 78
The Visual Constancies 78 Perception of Depth and Distance 81 Perception of Movement 84
Illusions 84
CONTENTS
3.3 Attention and Perception 86
3.4 Hearing 88 Three Functions of the Auditory System 88 Perception of Sound Waves 89
Pitch 89 Loudness 90 Timbre 91
The Auditory Apparatus 92 How the Ear Works 93
3.5 The Body Senses 94 The Vestibular Sense 94 The Skin Senses 94 The Kinesthetic Senses 96
3.6 The Chemical Senses 96 Olfaction 96
The Olfactory Organ 97 Taste 99
3.7 Adding Pieces of the Puzzle 99
Main Points 100 Study Terms 101
chapter 4 Learning 103
4.1 What Is Learning? 105 Approaches to Learning 105
4.2 Behavioristic Approaches 107 Classical Conditioning 107
Pavlov’s Experiments 107 Acquisition 109 Generalization and Discrimination 111 Extinction and Recovery 111 Contiguity 112 Blocking 112 Consequences 114
Operant Conditioning 114 The Skinner Box 114 The Basic Operant Conditioning Model 115 Shaping 116
Schedules of Reinforcement 117 Effects of Different Schedules 117 Types of Reinforcement 119
CONTENTS
Punishment 121 The Ethics of Punishment 121 Operant Conditioning and Human Behavior 122
4.3 A Transition to Cognitivism 123 Problems for Traditional Behaviorism 123 Insight 124
4.4 Cognitive Approaches 126 The Main Beliefs of Cognitive Psychology 127
Learning Involves Mental Representation 127 Learners Are Not Identical 127 New Learning Builds on Previous Learning 127
Bandura’s Social Cognitive Theory 127 Models 128 Reciprocal Determinism 128 Effects of Imitation 130 Humans as Agents of Their Own Behaviors 130
4.5 Practical Applications of Learning Principles 131 Applications of Behaviorism 131 Applications of Cognitivism 132
Main Points 133 Study Terms 133
chapter 5 Memory and Intelligence 135
5.1 What Is Memory? 137 The Filing-Cabinet Analogy 138
5.2 Stages of Memory 138 Sensory Memory 139 Short-Term Memory 140
Studying Short-Term Memory 140 Characteristics of Short-Term Recall 140 What Happens in Short-Term Memory: Baddeley’s Model 141
Long-Term Memory 142 Long-Term Memory Is Relatively Stable 143 Long-Term Memory Is Constructive 144 Understanding and Emotion Influence Memory 144 Rehearsal and Intention Influence Long-Term Memory 145 Two Kinds of Long-Term Memory: Explicit and Implicit 145 Two Kinds of Explicit Memory: Semantic and Autobiographical 146
Physiology of Memory 147 Neuroscience 148
Processes in Long-Term Memory 149
CONTENTS
5.3 Forgetting 150 Fading Theory 150 Repression 150 Distortion Theory 151 Interference Theory 151 Retrieval-Cue Failure 152
5.4 Improving Memory 153 Mnemonic Aids 153
Rhymes and Sayings 154 The Link System 154 The Loci System 155 The Phonetic System 155
5.5 What Is Intelligence? 156 Myths about IQ 156
Myth 1 156 Myth 2 156 Myth 3 156 Myth 4 157 Not a Myth 157
Views of Intelligence 158 Successful Intelligence: Sternberg 158 Multiple Intelligences: Gardner 159
5.6 Measuring Intelligence 161 The IQ 161 IQ Tests 161 Misuses and Abuses of Tests 162
5.7 Influences on Intelligence 164 Heredity and Environment 164
The Rubber-Band Hypothesis 165 Main Points 166
Study Terms 167
chapter 6 Motivation and Emotion 169
6.1 What Is Motivation? 171 A Definition 171
6.2 Physiological and Behavioristic Approaches 171 Instincts 171 Psychological Hedonism 173 Needs and Drives 173
CONTENTS
Physiological Needs 173 Psychological Needs 174
6.3 Maslow’s Hierarchy 176
6.4 Cognitive Views 176 Cognitive Dissonance Theory 178 Achievement Motivation 180 Attribution Theory 181
Locus of Control 181 Attributions and Need for Achievement 182
Self-Efficacy 183 Sources of Self-Efficacy Judgments 184 Efficacy and Expectancy-Value Theory 185
6.5 Emotions 187 Arousal 187
The Yerkes-Dodson Law 187 Need for Stimulation 188 Arousal Theory 189 Sources of Arousal 190
What Is an Emotion? 190 Emotional Expression 191
Theories of Emotion 192 The James-Lange Theory 192 The Cannon-Bard Theory 192 Schachter’s Two-Factor Theory 193 Recent Theories 194 The Dual-Pathway Model for Fear 196
Emotional Control 196 The Brain and Emotions 197 Cognitive Control of Emotions 198
6.6 Hunger and Sex Drive 199 Hunger Stimuli 199
Stomach Contractions 199 The Role of the Brain 200 Taste and Smell 200 Metabolic Factors 201
Obesity 201 Anorexia, Bulimia, and Binge Eating Disorder 202
Causes 203 Sexual Motivation 203
Hormonal Factors 204 Cultural and Other Factors 204
Main Points 204 Study Terms 205
CONTENTS
chapter 7 Human Development 207
7.1 The Beginning: Genetics and Prenatal Development 209 Chromosomes and Genes 210
Male or Female 211 The Genetic Code 211 Dominance and Recessiveness 213
Genetic Defects 216 Sex-Linked Defects 216 Non-Sex-Linked Defects 216 Chromosomal Disorders 216 Modifying Genetic Defects 217
Heredity and Environment 218 Prenatal Development 218
7.2 Infants 219 Physical and Motor Development in Infancy 219 Perception in the Newborn 220 Cognitive Development in Infancy 221
Cognition and Language Development 222 Social-Emotional Development in Infancy 223
Erikson’s Stages 223 Infant States 224 Infant-Caregiver Interaction 225 Infant Temperament 225
7.3 Children 227 Cognitive Development in Childhood: Piaget’s Theory 228
Mechanisms of Adaptation 228 Schemas 228 The Stage Theory 229 Evaluation of Piaget’s Theory 234
Children’s Social-Emotional Development 234 Initiative Versus Guilt 234 Industry Versus Inferiority 235 Play 235
7.4 Adolescents 237 Physical and Sexual Changes 237
Early and Late Maturation 238 Adolescent Egocentrism 238
The Imaginary Audience and the Personal Fable 239 Identity Formation 239
Identity Diffusion 240 Foreclosure 240 Moratorium 240 Identity Achieved 240
CONTENTS
7.5 Adults 241 Erikson’s Stages of Adulthood 241
Intimacy Versus Isolation 242 Generativity Versus Self-Absorption 243 Integrity Versus Despair 243
Main Points 243 Study Terms 244
chapter 8 Personality 247
8.1 Personality 249 Personality and Self 249
The Real Person 250 8.2 The Common-Sense Approach 250
8.3 The Trait-Type Approach 252 Early Trait-Type Approaches 254 The Big Five 255
Extraversion 256 Openness 256 Neuroticism 256 Conscientiousness 256 Agreeableness 256
Stability of Personality 257 8.4 Biological Approaches 258
Sheldon’s Body Types 259 Research on Somatotypes 259
Eysenck’s Biological Theory 261 Research Evidence 261 Eysenck’s Organization of Personality 262
8.5 A Psychodynamic Approach: Freud 263 Freud’s Basic Ideas 263
Three Components of Personality 263 Psychosexual Stages 264 Normal and Abnormal Personality 266 Defense Mechanisms 267 Review of Freudian Theory 268
8.6 Learning-Based Approaches 268 Behaviorism 268 Bandura’s Social Cognitive Theory 269
Observational Learning 269 Reciprocal Determinism 270
CONTENTS
Personal Agency 270 Relevance of Bandura’s Theory 270
Rotter’s Cognitive Approach 271 Externality-Internality 271
8.7 Humanistic Approaches 272 Abraham Maslow’s Self-Actualized Person 272 Rogers’s Phenomenology 273
8.8 Measuring Personality Variables 274 Projective Measures 274
The Rorschach 274 The Thematic Apperception Test 275
Nonprojective Measures 276 The NEO-PI-R 276 The MMPI-2 276
Some Cautions 277 Main Points 277
Study Terms 278
chapter 9 Psychological Disorders and Therapies 279
9.1 Historical and Current Views of Mental Disorders 281 Historical Views of the Causes of Mental Disorders 282 Current Definitions and Models 282
The Statistical Model 283 Medical/Biological Models 284 Behavioral Models 284 Cognitive Models 284 Psychodynamic Models 285 Which Model? 285 A Definition 286
Classifications of Disorders 286 The Most Common Disorders 289
9.2 Anxiety Disorders 290 Panic Attacks 290 Generalized Anxiety Disorder 291 Phobic Disorders 291
Agoraphobia 291 Social Phobias 292 Specific Phobias 293
Obsessive-Compulsive Disorders 293 Posttraumatic Stress Disorder 293
CONTENTS
9.3 Impulse-Control Disorders Usually First Diagnosed in Children 294 Aggression-Based Impulse-Control Disorders 294 Conduct Disorder 294 Attention Deficit Hyperactivity Disorder 295 Other Impulse-Control Disorders 295
9.4 Mood Disorders 296 Major Depressive Disorder 296 Bipolar Disorder 296 Dysthymic Disorder 297
9.5 Substance-Related Disorders 297 Substance Use Disorders 297
Prevalence and Types of Drug Use 298 9.6 Other Axis I Disorders 300
Dissociative Disorders 300 Dissociative Amnesia 300 Dissociative Fugue 300 Dissociative Identity Disorder 301 Depersonalization Disorder 302
Psychotic Disorders 302 Schizophrenia 302 Causes 303
Sexual and Gender Identity Disorders 303 Gender Identity Disorders 303 Paraphilias 304 Sexual Dysfunctions 304
Somatoform Disorders 304 9.7 Axis II Personality Disorders 305
9.8 Therapies 306 Medical Therapy 306
Drug Therapy 307 Psychosurgery 307
Insight Therapy 307 Learning-Based and Cognitive Therapy 308
Behavior Modification 309 Positive Reinforcement 309 Rational Emotive Behavior Therapy 309
The Effectiveness of Therapies 311 Main Points 311
Study Terms 313
CONTENTS
chapter 10 Social Psychology 315
10.1 Social Psychology 317 What Is Social Psychology? 317
10.2 Attitudes and Attitude Change 317 Compliance and Conformity 319 Social Pressure and Compliance 319 Obedience 321
The Milgram Studies 322 The Prison Experiment 324
Persuasion 325 Importance of Message Characteristics 325 Importance of Message Source 325 Importance of Audience Characteristics 326
Cognitive Dissonance 326 Attribution and Attitude Change 327
Overjustification 327 10.3 Antisocial Behaviors 328
Aggression and Violence 328 Theories of Aggression 328 Violence in Society 333
Bystander Apathy 334 The Bystander Effect 335 An Explanation 336 How Common Is the Bystander Effect? 337
10.4 Prosocial Behaviors 338 Altruism 338
10.5 Interpersonal Relationships 339 The Rules of Attraction 340
Propinquity 340 Similarity 340 Physical Attractiveness 341
Liking and Loving 342 A Model of Love 343 A Last Word to the Poets 346
Main Points 346 Study Terms 347
Glossary 349 References 373 Photo Credits 409
About the Author
Guy R . Lefrançois makes few claims to anything notable . “I’m an obscure French Canadian from a long line of obscure ancestors,” he insists . “Like me,” he says, “most are better remem- bered not for the things they did but for those they never accomplished . Some of the things I haven’t done yet are truly amazing!” He cur- rently holds an appointment at the University of Alberta, where he also received his PhD and where he first started teaching in 1966 . Since then, he has written numerous books in psy- chology, many of which have been translated into other languages, including Chinese, Russian, Italian, Spanish, French, and German (he does not speak all these other languages) . He has been happily married to Marie for more years that he can easily count and loves to fish, watch birds, pick berries, read other people’s words, and go on extended bicycle tours . He has 3 children (Laurier, Claire, and Rémi), and 5 grandchildren, to whom this book is dedicated .
Preface
Dear Reader,
The purpose of Psychology: The Human Puzzle is to explore psychology’s view of one of the most captivating and puzzling of all topics: ourselves . Its content is the story of the search for pieces of this puzzle and an account of how the pieces have begun to fit together . Its purpose is to teach .
But good teaching is more than just telling a story . It isn’t enough simply to gather and organize pieces of the puzzle and squeeze them into a text . Good teaching also requires motivating, illustrating, explaining, relating, evaluating, reviewing, maybe even inspir- ing . Good teachers sometimes have to do awesome somersaults and leap over burning buildings and juggle burning brands while balancing on tall ladders . Really .
Psychology: The Human Puzzle tries to be a good teacher . It illustrates and explains; it evalu- ates and reviews; it tries to inspire . Sometimes it pauses to tell stories about the heart- warming generosity of strangers, to shock with accounts of the misbehavior of violent adolescents, to intrigue with descriptions of mental disorders in other cultures, to amaze with tales of astonishing memories, to move with an analysis of the thing we call love . At least once that I can think of, it nearly does a somersault and even juggles a few things that, from far away, almost look like burning brands .
Characteristics of Psychology: The Human Puzzle
Psychology: The Human Puzzle has a number of characteristics intended to make it as useful a teaching-learning tool as it can be .
The graphic layout and format are designed with the student in mind . Pages are unclut- tered; text material flows with little interruption . All the important stuff is right in the text; there are no boxed inserts, sidebars, marginal notes, or other little gizmos to grab your eye and make you wonder where to go next . All the graphics and photographs are relevant, and definitions of important terms are gathered in the glossary . A brief summary and a list of important study terms follow each chapter .
Although it assembles all the important and essential pieces of the puzzle, this book is deliberately shorter than most other comparable textbooks, so that it can comfortably be covered in a single course .
I hope you enjoy and learn . I suspect that each is necessary for the other .
Sincerely,
Guy R . Lefrançois
PREFACE
Dear People Involved with the Making of this Book,
Most of you know who you are . Sadly, I don’t know many of you . But I deeply appreci- ate everything you have done . The reviews were remarkably intelligent, and I am truly grateful to the instructors who shared their thoughts on the manuscript . I owe a debt of gratitude, as well, to Steve Wainwright, Sponsoring Editor, who initiated the project and guided its first steps, and to Dan Moneypenny, Development Editor, who developed the project astonishingly smoothly and rapidly . Thank you as well to Kim Purcell, Media Edi- tor, the copy editor, Susan Zorn, who cleaned up my mess so effortlessly, and to Shawn Vazinski of Lachina Publishing Services, and Illustrator Maury Aaseng . Finally, thank you to my amazing family, who nurture my work and my leisure, and to the University of Alberta for providing such a rich environment in which to look for pieces of the puzzle .
Sincerely,
Guy R . Lefrançois
Acknowledgments
1
The Science of Psychology
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • How is psychology defined? • What are the principal responsibilities of members of the main divisions in psychology? • What were the key beliefs and contributions of some of the early contributors to
the development of psychology? • What are the identifying characteristics of the scientific method? • What are some key types of descriptive research? • How does descriptive research differ from experiments and ex post facto studies? • What is the correlation fallacy? • What are some of the main sources of error in interpreting the results of psycho-
logical investigations?
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CHAPTER 1The Science of Psychology
1. Boldfaced terms are defined in the glossary.
The purpose of psychology is
to give us a completely different idea of the things we
know best. —PaulValéry,Tel Quel,1943
Chapter Outline
1.1 What Is Psychology? What Psychologists Do
1.2 The Beginnings of Psychology Recent Origins of Psychology
1.3 Principles of Science The Scientific Method
1.4 Sources of Psychological Information Descriptive Research Experiments Ex Post Facto Studies
1.5 Cautions in Interpreting Psychological Research
Experimenter Bias Subject Bias Sampling Bias Other Problems of Psychological Research
1.6 Philosophical Issues and Psychological Controversy
1.7 Psychology’s Relevance
1.8 This Book
My grandmother was convinced she knew best. “Not true,” she would declare when I tried to tell her what I was learning as a novice psychology student. And then, her knitting needles clacking, she would go on to inform me that boys who mature early are always messed up later. She also believed that people use only 10 percent of their brain because that is what she had read somewhere. And she knew that those suffering from mental disorders are like night and day from her and other sane people. Nor did she trust psychologists: “They have sneaky ways of looking into people’s minds,” she informed me. “Except people who have ESP powers.”
“And mark my word,” she said one time; “most geniuses are crazy.” “But you don’t have to worry,” she added.
These and a wide range of similar beliefs make up what is sometimes called bubba psychology1 (bubba or bubbe—or sometimes bubbie—means “grandmother” in some Eastern European lan- guages). Bubba psychology is also labeled naïve psychology or folk psychology.
Psychological research has not been kind to many of my grandmother’s beliefs—which is not to say that all our folk wisdom is untrue or that psychology’s beliefs are always correct. In fact, much of our folk wisdom is correct; and psychology, like most sciences, does occasionally change its mind.
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CHAPTER 1Section 1.1 What Is Psychology?
1.1 What Is Psychology?
My grandmother’s belief that psychologists have devious ways of peering into one’s mind is one reason why it is important to have a clear understanding of what psy- chology is and is not. While it’s true that its goal is to solve the puzzles of human thought and behavior, it is a science and not a collection of special powers.
In its simplest sense, psychology is the science that studies behavior and mental processes. Unfortunately, this definition does little justice to the tremendous variety of activities and interests that make up the field. In fact, members of the American Psychological Asso- ciation divide themselves into 54 different divisions (APA, 2010). These divisions reflect different interests and specializations, such as the study of aging or the application of psychological knowledge and principles in clinical settings.
What Psychologists Do
As Figure 1.1 shows, the vast majority of psychologists are involved in the practical appli- cation of psychological knowledge.
Clinical 52%
11%
Others 19%
Social 2%
Main Specialties in Psychology
Industrial/Organizational 4%
Experimental 1% Educational 2%
Developmental 3%
Counseling
Health 2%
School 4%
Figure 1.1
Main specialties in psychology. Based on a survey of the American Psychological Association’s 90,221 members in 2005. Data from APA Directory Survey 2005, compiled by APA Research Office. Retrieved July 13, 2010, from http://www.apa.org/workforce/publications/05-member/ table-3.pdf.
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CHAPTER 1Section 1.1 What Is Psychology?
Clinical Psychologists About half of all psychologists are clinical psychol- ogists. These are typically psychologists working in a hospital or clinical setting. They specialize in helping people with psychological problems such as anxiety, depression, addiction, or relationship problems.
Although psychiatrists and clinical psychologists often treat similar sorts of problems, their training and expertise are quite different. Psychiatrists are medical doctors with specialized training in iden- tifying and treating mental and emotional disor- ders. In addition to the various other interventions they might use, they can prescribe drugs, which are now commonly used to treat many disorders ranging from mild anxiety to severe deviations from normality. In most jurisdictions, clinical psy- chologists cannot write prescriptions.
Counseling Psychologists A significant number of psychologists are coun- seling psychologists. They, too, treat problems related to emotional and mental disorders. In addition, they also deal with issues such as those having to do with vocational choices, learning problems, relationships, and related concerns. Whereas clinical psychologists often work in clinical settings or in private practices, counseling psychologists work mainly in private practices.
Industrial/Organizational Psychologists Roughly 4 percent of psychologists are classified as industrial/organizational psychologists. They are concerned mainly with work-related issues, such as determining how to hire the right person for a job, improving job satisfaction, increasing motivation in the workplace, reducing stress, and managing goals.
School Psychologists School psychologists deal with behavioral and learning problems that affect schoolchil- dren. They are often called upon to administer tests, to diagnose learning and behav- ior problems, and to suggest treatment for these problems. As a result, they are usually
Psychology, like most sciences, occa- sionally changes its mind. We’re no longer certain that the bumps and lumps on our skulls are roadmaps to our personalities.
Psychology hasn’t yet discovered some devious way of peering into our persons and ferreting out all the dark secrets therein.
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CHAPTER 1Section 1.1 What Is Psychology?
trained in both psychology and education and are often required to apply the principles of clinical and counseling psychology, as well as those of educational psychology.
Educational Psychologists Psychologists concerned specifically with improv- ing teaching and learning are educational psychol- ogists. Unlike school psychologists, they are less concerned with individual behavioral and learn- ing problems than with broader questions relating to how people learn in educational settings. Educa- tional psychology applies psychological principles to classroom management, special needs educa- tion, instructional design, and lesson planning.
Developmental Psychologists Developmental psychologists study systematic changes that occur between conception and death. Some specialize in the study of child develop- ment; others are more concerned with adolescent or adult development, or with aging and dying. The findings of developmental psychology are especially important for school and educational psychologists as well as for clinical and counseling psychology.
Experimental Psychologists Much of the content of psychology—and therefore of this text—is based on the work of experimental psychologists. They specialize in the use of experimental methods to inves- tigate the puzzles of psychology. Experimental research requires that the investigator control significant aspects of a situation in an attempt to uncover cause-and-effect rela- tionships. (There is more about experiments shortly.)
Other Divisions There are many other specializations in psychology: Health psychologists look at how psy- chological factors influence health and illness and often work in clinical settings or hospi- tals to promote wellness; social psychologists are concerned with how people relate to and influence each other; sports psychologists use psychological research to improve athletic performance; forensic psychologists are usually experts in criminal law as well as in psy- chology and might be called upon to assist in jury selection or as expert witnesses for assessing the state of mind of the accused at the time of the offense or the defendant’s competency to stand trial; and environmental psychologists look at the relationship between humans and their surroundings, and specifically at the effects of the environment on our well-being (Table 1.1).
About half of all psychologists are clinical psychologists specialized in helping people with psychological problems. Unlike psychiatrists, they’re not usually medical doctors.
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CHAPTER 1Section 1.2 The Beginnings of Psychology
Table 1.1 What Psychologists Do
Some Major Divisions Main Concerns and Activities
Clinical Diagnosis and treatment of emotional illnesses and disorders, frequently in a hospital or clinical setting
Counseling Evaluation of and assistance with behavioral, emotional, and other problems not serious enough to require hospital, clinical, or psychiatric treatment; assistance with important decisions such as those having to do with careers, relationships, adjustment, and stress
Industrial/organizational Applying psychology in business and industry; developing and adminis- tering tests to evaluate aptitudes; dealing with motivational, manage- ment, and interpersonal issues in the workplace
School Identifying individual aptitudes and skills among learners in a school setting; developing and administering tests pertinent to school-related abilities; diagnosing and remediating behavioral and learning problems
Educational Researching the application of psychological principles for improving teaching and learning
Developmental Studying changes that define growth, learning, and maturation from birth to death; applying findings in educational programs and in child guidance and counseling
Experimental Using experimental methods to investigate the puzzles of psychology
Regardless of their specialization, many psychologists write books, teach, do research, conduct private practices, work in business and industry, or are employed in a variety of different professions where knowledge of psychology is useful and sometimes even essential. Many are engaged in combinations of these activities.
All that affects human behavior, thought, and emotion falls within the domain of psychol- ogy. This text, with its 10 chapters and many sections, represents the most common divi- sions and interests in psychology: It is a 120,000-word definition of psychology.
1.2 The Beginnings of Psychology
That definition begins with the history of psychology—a history that goes back at least as far as ancient Greece, when the discipline of philosophy embraced almost all other disci- plines, including what is now psychology. In fact, the term psychology has its roots in the Greek language, where the word psyche means “soul” and logos means “the study or discussion of.”
More recently in psychology’s history, discoveries in medicine had a dramatic influence on our conception of the human being. When William Harvey discovered that the heart pumped blood into tubes throughout the body, many thinkers became convinced that people were nothing more than elaborate pumping machines. Many suspected that the ability to think originates in the blood. Aristotle didn’t merely suspect this—he knew it. If a person’s blood were entirely removed, he argued, no evidence of thinking would remain!
Early physics, too, contributed to the development of psychology. The psychological importance of Sir Isaac Newton’s observation that apples invariably fall earthward lies
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CHAPTER 1Section 1.2 The Beginnings of Psychology
in the fact that it illustrates a different way of looking at natural phenomena. The ancient Greek philosophers undoubtedly knew that apples fall earthward. And had they wanted to know why apples fall, they might have thought long and hard about the problem and held learned discourses with colleagues. But their approach would have made little use of the methods of science as we now know them. Newton, however, felt compelled to demonstrate and verify the phenomena he observed and to investigate them by means of controlled experimentation. We are products of Newton’s generation: Psychology, anthro- pology, sociology, and other related fields are seldom referred to as the social studies; they are the social sciences (Figure 1.2).
Recent Origins of Psychology
Scientific psychology is not much more than a century old. Its founder is generally con- sidered to be Wilhelm Wundt, who founded the first psychological laboratory in Leipzig,
Aristotle Newton Pavlov
Figure 1.2
Contemplation of their own experiences guided the ancient Greeks in learning about people. The result: the theory that the ability to think originates in the blood. Centuries later, Newton used scientific observation and experimentation to test theories about the physical world. By the 20th century, psychologists were applying scientific methods to animals and people to learn about behavior. The result: psychology as it exists today.
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CHAPTER 1Section 1.2 The Beginnings of Psychology
Germany, in 1879. Many of Wundt’s students later established laboratories of their own throughout Europe and North America. Very soon after that, psychology departments opened at all major universities. Typically these began as branches of departments of phi- losophy, but in time the discipline became totally separate. Departments of psychology now claim far more students than do departments of philosophy.
Structuralism The early history of psychology is marked by the rise—and fall—of a number of different “schools” of thought. The first dates back to Wilhelm Wundt and his followers, whose search for pieces of the puzzle relied on introspection. Introspection involves looking inside oneself, examining one’s own thoughts, feelings, and motives and generalizing the resulting insights to understand the thoughts and feelings of others. Stop, for a moment, and think about the words you are now reading. How does a physical stimulus such as a word on a page affect you? As you carefully analyze your current thoughts and feelings, you are introspecting.
The goal of introspection as practiced by Wundt and his followers was to understand the structure of thoughts, emotions, and motives. They reasoned that the conscious mind, like any other natural object, must comprise identifiable elements. In the same way as water is made up of two atoms of hydrogen and one of oxygen, so too must sensations and feel- ings be structured of basic mental elements. One of his followers, Titchener, called this approach structuralism.
Functionalism William James, widely credited with being the founder of American psychology, thought it a waste of time to try to explain the mind by looking at its structure. Heavily influenced by Charles Darwin’s new theories, James argued that it would be far better to try to deter- mine the purposes that drive behavior—that is, its functions; hence the label functionalism. James’s 1,000-page book, The Principles of Psychology (1890), did a great deal to establish what psychology would become. It is James, for example, who first wrote of the “stream of con- sciousness” and of the baby’s world as “one great blooming, buzzing confusion.” Among the topics in his book are will, interest, emotions, sensation, the brain, and, of course, the stream of consciousness. He asks questions such as “How can people strengthen habits?” “How does intention motivate action?” “What is memory, and how does it work?”
Behaviorism James’s functionalism profoundly influenced the subsequent development of psychology. But by the early 1900s, many psychologists, especially in the United States, had begun to reject difficult and subjective topics such as mind and thinking. Led by the psycholo- gist John Broadus Watson, they chose to concentrate on the objective, observable aspects of behavior; hence the label behaviorism. Behaviorism “emphasized publicly observable stimuli (s) and responses (r) and spurned supposedly unobservable, centrally initiated processes like consciousness” (Moore, 2010, p. 143).
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CHAPTER 1Section 1.2 The Beginnings of Psychology
Among the most important behaviorists are Wat- son and Skinner. Behaviorists tend to study reflex- ive behavior and the consequences of behavior. As we see in Chapter 4, many scientific experi- ments can be carried out to investigate these mat- ters. As a result, with the advent of behaviorism, psychology became progressively more scientific. But because of its emphasis on discovering how behavior is controlled by stimuli and by its conse- quences, behaviorism is sometimes interpreted as denying the existence of free will.
Psychodynamic Theory At about the same time that the behaviorists were first popular in American psychology, the Aus- trian neurologist Sigmund Freud was developing startling new ideas about the mind. As explained in Chapter 8, Freud believed that the mind is a little like an iceberg: We see only the very tip, which represents the conscious mind; the bulk of it is hidden, unconscious. Much of our behavior
is driven by unconscious forces: They lie beneath the visible iceberg, beyond our con- scious awareness. Freud believed that many of our emotional disorders stem from these unconscious psychodynamic forces. There are methods of analysis, of psychoanalysis, explained Freud, that can uncover these hidden motives and forces and that can lead to the alleviation of mental disorders.
Cognitivism Other psychologists rejected the narrow emphases of a behaviorism that limited itself to observable events, but relatively few embraced Freud’s psychoanalysis. Many can be described as belonging to the school labeled cognitivism. These are psychologists whose main concerns are with intellectual (cognitive) events such as problem solving, thinking, information processing, and imagining. Cognitivism provides explanations for behavior based on our ability to symbolize, to uncover cause-and-effect relationships, to determine what goes with what, and to anticipate the consequences of our actions.
Humanism Some psychologists object to what they see as the overly limited, mechanistic, and dehumanizing emphases of behavioristic approaches to psychology. They also reject the Freudian notion that we’re driven by dark, unconscious forces over which we have little control. These approaches, they argue, pay too little attention to the positive and healthy aspects of human nature. Humanistic psychology, as we see in Chapter 8, is concerned with the uniqueness, the individuality, the humanity of each person. It
Psychoanalysts are psychiatrists who, like Freud, believe that mental disor- ders result from deep-seated psycho- dynamic conflicts. The purpose of the couch is to allow the patient to relax so as to facilitate uncovering these con- flicts—often through free association or dream analysis.
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CHAPTER 1Section 1.3 Principles of Science
emphasizes the development of the “self” and is represented by psychologists such as Abraham Maslow and Carl Rogers.
Humanism arose primarily as a reaction against behavioristic and psychodynamic theo- ries, which Maslow (1998) described as the two great forces in psychology; he labeled the humanistic movement third force psychology. His hope was that this third force would become as powerful as the first two and that it might counter the dehumanizing influence of a rigorous scientific approach to the study of psychology.
Other Orientations There are a number of other important orientations in the study of psychology. Evolution- ary psychology emphasizes biology and genetics as a source of explanations for human learning and behavior. Evolutionary psychologists look at the evolution of human behav- ior and try to explain human characteristics in terms of historical pressures of adaptation.
Neuroscience is another important and highly current, biologically based orientation. Using powerful new brain-imaging techniques, neuroscientists look to the nervous sys- tem, especially the brain, for explanations of consciousness and of mental processes like thinking, imagining, problem solving, and remembering.
Both evolutionary psychologists and neuroscientists make extensive use of genomics, the study of genes and how they relate to human behaviors and characteristics.
1.3 Principles of Science Psychology is a science. What does that mean?
In one sense, science can mean a collection of information in a field of study. For example, the science of physics is a collection of information about the nature of matter and energy and how they interact. And the science of psychology is a collection of information about human thought and behavior and how they interact.
In another very important sense, science is a way of dealing with information. As such, it is both an attitude and a set of guidelines. It is an attitude that insists on objectivity, preci- sion, and consistency. And it is a set of guidelines meant to ensure that this is the case. As a result, science stands in sharp contrast to those ways of knowing that are based princi- pally on subjective analysis or introspection.
Attempts to explain and organize the observations of science take the form of theories. Theories are collections of related statements that clarify observations and permit predic- tions (hypotheses).
In spite of science’s preoccupation with the objective, many topics of interest to psychol- ogy cannot be observed and measured directly, but can only be inferred from behavior or from highly subjective self-reports. Emotions and thoughts, for example, are subjec- tive rather than objective. And even though these might lead to behavior from which
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an observer might guess the underlying emotion or thought, this is not always so. For example, I might be very angry or very sad because I now know for sure that my dog does not much like me; but you would not necessarily know my emotion from my behavior because I can easily pretend I don’t care.
One of psychology’s tasks is to devise ways of examining nonobjective events and states as objectively and scientifically as possible.
The Scientific Method
Studying phenomena objectively and scientifically means using what is often labeled the scientific method—an approach designed to ensure that observations are as accurate and valid as possible, that they can be replicated by other investigators. The sciences have now been using the scientific method for more than a hundred years to find and assemble pieces of the human puzzle. It can be described in terms of five systematic steps:
1. Ask the question. (For example: Would after-school detention be effective in stop- ping a group of boys from stealing iPods, MP3 players, and smartphones?)
2. Develop a hypothesis. On the basis of observation and a careful examination of relevant investigations and theory, make a prediction—a hypothesis. By definition, a scientific hypothesis is unproven and can be falsified (proven incorrect). Hence the outcome of a scientific investigation can lead to the rejection of the hypothesis. (Hypothesis: After-school detention will be effective in curtailing thefts of elec- tronic devices.)
3. Collect relevant observations. As we see in the next section, science suggests many different ways of collecting observations. The nature of the question being asked, as well as constraints related to money, time, instrumentation, and the availability of suitable participants, usually determines which method is best. (Method: Detain the group of thieves after school; monitor subsequent thefts.)
4. Test the hypothesis. Do your observations indicate that the hypothesis should be rejected? And even if they do not, might they be due to chance? Science is very concerned that observations might be just chance happenings—in which case, they don’t mean very much at all. For this reason, investigators often use special sta- tistical procedures to determine whether observations are statistically significant. These procedures allow investigators to
Although psychology probes and mea- sures things not as easily analyzed and quantified as matter in test tubes, it strives for the same precision, objectiv- ity, and replicability—though perhaps with somewhat more restraint than this mad scientist.
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CHAPTER 1Section 1.4 Sources of Psychological Information
determine the likelihood that observations are due to factors other than chance. (How many devices disappeared before the detention? How many disappeared after?)
5. Reach and share a conclusion. If science is to progress, the hypothesis has to be rejected or not rejected. If it is not rejected, it may be accepted as tentatively valid (we can seldom be absolutely certain). (For example: As many electronic devices disappeared after as before detention. Tentative conclusion: Detention is not an effective deterrent in this case.) The conclusions of the research then need to be shared. This means communicating the findings to others so they can apply them and so continue the research and learning process.
1.4 Sources of Psychological Information
The ways psychologists gather observations vary greatly depending on the topic being researched and sometimes on the psychologist’s preferences. What is invariably true, however, is that observation is the source of all psychological knowledge, just as it is the source of knowledge in other sciences. Psychological studies and experiments vary according to who is being observed, when, how, and under what conditions.
Descriptive Research
Descriptive research describes the characteristics of an individual or of a group. It answers the questions who, what, where, when, and how. What is the average age of a group? How common is bipolar disorder? What is current life expectancy in North America?
Descriptive research is often based on the results of archival research—research that depends on secondary sources such as census data, birth certificates, or other forms of past records. It may also be based on the results of observation, which can be naturalistic or nonnaturalistic.
Naturalistic and Nonnaturalistic Observation Naturalistic observation is observation that occurs in natural settings rather than in labora- tories, hospitals, and other surroundings. Naturalistic observation is well illustrated by the research of Jane Goodall, who, since 1960, has lived among chimpanzees in the Gombe Stream Research Centre in Tanzania, simply observing chimpanzees without disturbing them. The assumption of naturalistic observation is that if the investigator does interfere, the behavior under examination may be affected. For example, chimpanzees that would be playful and bold in their natural state might become anxious and furtive when observed too closely.
Naturalistic observation takes place in surroundings that are not altered by the observer or by the requirements of the observation; nonnaturalistic observation occurs in more contrived surroundings such as laboratories. Both are important in psychological investigation. Natu- ralistic and nonnaturalistic approaches to gathering psychological information can be classi- fied in terms of who is observed and how and when the observations are made. Thus, there are case studies (discussed in next section), where single individuals (or single units such as
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CHAPTER 1Section 1.4 Sources of Psychological Information
a family) are observed, and surveys (discussed after case studies), where large groups of individuals (or larger groups of units such as a number of families) are studied.
Studies may be longitudinal or cross-sectional, depending on when observations are made. When the goal of psychological investigation is to identify changes that occur within individuals or within a group of individuals over time, longitudinal stud- ies may be used. A longitudinal study examines the same individual(s) at different times and makes direct comparisons between the individual at this point in time and the same individual at an earlier time. In contrast, cross-sectional studies examine two or more groups of subjects at the same time.
Cross-sectional studies are much less time-consuming and consequently much less expen- sive, but they are not always appropriate for answering questions about changes that occur within individuals over time.
Torrance’s study of creativity, in which subjects were followed from childhood beginning in 1958 through a period of 50 years, provides one of the better-known examples of longi- tudinal research in psychology (Millar, 2001, 2010). Investigators kept track of all creative accomplishments of each individual in the group: books written, art exhibitions, software programs, inventions, invited lectures, leadership positions, and so on. This investiga- tion found that highly creative children tend to become highly creative adults. The most highly gifted grew up to be college presidents, inventors, doctors, diplomats, and lawyers. Strikingly, their scores on measures of creativity were far more predictive of their eventual accomplishments than were their scores on intelligence tests (Plucker, 1999).
Case Studies Descriptive research, as we noted, can be based on case studies. A classic example of a case study is that of a young Russian, known to us only as S, who presented himself to a psy- chologist one day. S was confused and poorly adjusted. He hoped that the psychologist, the very well-known and highly respected Alexandr Romanovich Luria, would help him. His problem was that he had difficulty following ordinary conversations, that his mind was such a jumble of sights and sounds that he was often absolutely overwhelmed and bewildered. From this initial meeting there developed a long relationship between the two, during which Luria conducted intensive and detailed investigations of S’s memory. Luria soon discovered that S could remember with incredible and uncanny accuracy. Nor did he remember as you or I might remember, painfully retrieving some isolated bit of information that we have suc- ceeded in storing and protecting from the ravages of time. He could remember in infinite detail, retrieving from his memory not only the item requested of him, but a host of other associations that most people would never have noticed initially, let alone remembered.
As an example, one day Luria presented S with a table of 50 single-digit numbers. S spent three minutes examining the array. He then reproduced the entire table in 40 seconds and could read off any number it contained in horizontal, vertical, or diagonal arrangements.
Naturalistic observation involves as little interference with ongoing activi- ties as possible and occurs in “natural” environments such as schools or, as shown here, playgrounds.
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CHAPTER 1Section 1.4 Sources of Psychological Information
Perhaps even more amazing, when S was asked to reproduce the same table several months later (the table had not once been presented in the interim), he could do so unerr- ingly and just as rapidly. The only difference was that the second time he required a brief period to “re-imagine” the situation in which he had first memorized the table.
As a result of this intensive and prolonged case study, Luria discovered that S didn’t simply hear sounds but sensed them as vivid and colorful images; that he could remem- ber the clothing he and Luria had been wearing on a given day years before; that he fre- quently remembered by “seeing” objects, events, or numbers in mental images of places where he had stored them. Sometimes he would imagine he was walking along a very familiar street in his hometown, and he would mentally place different numbers on vari- ous fences, trees, and houses along this street. Later, when called upon to remember these numbers, he would simply imagine the street and read off the numbers as he saw them. On one occasion when he couldn’t recall a number he had memorized in this fashion, it eventually occurred to him that he had “placed” the number in question on a dark, heav- ily shaded piece of broken board and that he simply could not “see” it!
S presents a classic case of what is termed synesthesia, a condition where one sensation evokes another related to a different sense. For example, a person with synesthesia might hear a color or see a taste or an odor. It seems that S’s synesthesia provided him with an extraordinarily vivid assortment of visual images that later became keys to his memory.
Luria’s investigation of S’s memory and his subsequent reports of the results of this inves- tigation provide us with a striking example of a case study. Numerous other examples can be found in psychological literature, especially in studies of abnormal behavior. When- ever a psychologist requires extensive and in-depth information about a single individual, a case-study approach is likely to be used.
Surveys Descriptive studies are often based on surveys. Whereas a case study involves a single individual (or a single unit), surveys involve groups of individuals or groups of units. Case studies are often inappropriate when the intent is to describe a group of people. A psychologist who wanted to find out what the average person in the street thinks of a polit- ical event could not easily accomplish this by walking up to and questioning an “average” person. In the first place, there is no average individual: he or she is an invention. When a researcher refers to the average person, it is never a single person being referred to; it is, instead, the nonexistent, idealized “averaged” result of investigating many individuals.
A survey is a research technique that attempts to discover the qualities of the average per- son by examining the characteristics of a number of real individuals. What is especially important in doing a survey is that those being surveyed be representative of the entire group to which investigators want to generalize. When researchers wanted to discover the sexual beliefs and behaviors of the average British 16- to 44-year-old, they surveyed 11,161 individuals by means of interviews and computer-based questionnaires (Gerressu, Mer- cer, Graham, Wellings, & Johnson, 2008). They were then able to state that 73 percent of men and 37 percent of women had masturbated at least once in the preceding four weeks. Had they conducted two case studies instead, one male and one female, and generalized in the same manner, they would have had to state that all men or all women between the
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CHAPTER 1Section 1.4 Sources of Psychological Information
ages of 16 and 44 have masturbated at least once, or that none of them have. Either con- clusion would have been highly misleading. (See Figure 1.3 for a comparison of surveys, longitudinal research, and cross-sectional research.)
Correlational Research A great deal of psychological research is intended to find out whether there is a relation- ship between two variables. Often psychological research tries to answer questions such as: Is hyperactivity related to parental upbringing? Does anxiety contribute to poor test performance? Are attractive people more likely to be successful in business?
Surveys reveal information about groups of individuals at a specific time. But a single survey provides no information about change over time and it gives only a composite picture of an idealized “average” individual.
Longitudinal studies provide information about one or more individuals over a period of time. But they are expensive and time consuming. Many cannot be completed in the lifetime of a single investor.
Cross-sectional studies can provide information about different groups at the same time. But, like surveys, they provide statistical averages and may not take all variables into account. For instance, did the 70-year-olds grow up with the same develop- mental stimulation as 35-year-olds, or 5-year-olds?
What is the average American IQ?
How stable is an individual’s IQ?
Does IQ peak at different ages?
A d
a m
’s I Q
Adam’s age (years)
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80
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0 5 10 15 20 80...
?
60 80 100 120 ...
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35-year-olds
70-year-olds
5-year-olds
Figure 1.3
Surveys, longitudinal studies, and cross-sectional studies are examples of descriptive research designed to answer different questions.
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CHAPTER 1Section 1.4 Sources of Psychological Information
Research designed to answer questions such as these typically results in a measure of correlation and is therefore called correlational research. A positive correlation exists between two variables when a change in one of these variables is reflected in a similar change in the other; a negative correlation is observed when a change in one variable is accompanied by an opposite change in the other. Numerically, correlation is expressed as –1.00 for a perfect negative correlation, +1.00 for a perfect positive correlation, and 0 for lack of correlation (Figure 1.4).
C: Low correlation
B: High negative correlationA: High positive correlation
Subject
Ron
Edna
Sarah
Bill
Jo
Sue
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re s
o n
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t 2
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Scores on test 1Scores on test 1
Scores on test 1
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Figure 1.4
Graphic representations of correlation. In A (high positive correlation), those who scored well on test 1 tended to score well on test 2. In B (high negative correlation), those who did well on test 1 tended to do correspondingly poorly on test 3. And in C, there is little relationship between scores on test 1 and scores on test 4.
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CHAPTER 1Section 1.4 Sources of Psychological Information
It would seem logical to assume that if there is a high positive correlation between two variables, one must cause the other—and that may sometimes be the case. In fact, if a vari- able does cause another, there will be a correlation between the two. Put another way, cor- relation is essential evidence of causation—but it isn’t sufficient evidence. The assumption that correlation proves causation is known as the correlation fallacy.
For example, there is a high positive correlation between children’s shoe sizes and their ability to read. But it would be a correlation fallacy to conclude that having big feet helps children read. Having big feet, like being able to read, simply reflects the child’s continued development and growth. (The correlation fallacy is explained more fully in a later section.)
Experiments
An experiment is a research procedure where investigators control one or more of the variables in a situation and observe the effects this has on other variables. The experiment is a very powerful tool in science’s quest for knowledge because controlling variables makes it possible to observe and measure causes and effects.
A variable may be a measurement, an outcome, or some other way of describing or classify- ing things such as people, events, or objects. Intelligence test scores, environmental factors, physical characteristics, medications, and so on are all examples of variables. Variables the experimenter controls and whose effects are being investigated are independent variables; variables that may be affected by changes in the independent variables are dependent variables. Independent variables are assumed to have an effect on dependent variables. Dependent variables are ordinarily measured at the end of an experimental procedure.
As a simple illustration, an experiment can easily be designed to determine whether a new approach to teaching is better than the current approach. The experiment would require that subjects be assigned to one or the other of the teaching methods, that the methods be put into practice, and that subsequent performance be measured and compared. In this case, teaching method is an independent variable; performance, a dependent variable. If teaching method affects performance, it (the independent variable) may be used to predict learning (a dependent variable) (see Figure 1.5).
Note that most experiments can be reworded in terms of an “if-then” statement. What the investigator is saying is “if such and such, then such and such.” The if-then statement is the hypothesis (prediction) that the experiment is designed to investigate. The “if” part of the statement usually defines the independent variable; the “then” part of the statement is the dependent variable. For example, the hypothesis “rewarding learners will have a positive effect on their learning” can be reworded to “if learners are rewarded, then they will learn more effectively.”
Experimental and Control Groups The most common experiment is that which makes use of an experimental group and one or more control groups (sometimes called comparison groups). When the manufacturer of
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CHAPTER 1Section 1.4 Sources of Psychological Information
some exotic toothpaste assures us that it leads to 40 percent fewer cavities, we are some- times told that one group brushed regularly with the new product while a second group brushed with their regular toothpaste. Comparison of teeth between these two groups then enabled investigators to determine the extent to which the new product prevents cavities. Cavities are a dependent variable in this experiment; toothpaste employed is an independent variable. Similarly, the group to which something is done (in this case the group given the new toothpaste) is an experimental group; the group that is used for com- parison is a control group. Without the control group for comparison, we would never know whether simply brushing with any toothpaste decreases the incidence of cavities.
Any experimental design that does not employ comparison groups similar in as many relevant ways as possible to the experimental groups cannot be relied upon, since we
Experimental group (Students are taught using new method A.)
Hypothesis: New teaching method A is more
effective than conventional method B for teaching Introductory Psychology.
Grades obtained by members of the experimental group are compared with those of the
control group.
Control group (Students are taught with the
conventional method B.)
Students are randomly assigned to one of two groups.
Independent variable
Dependent variable
Figure 1.5
A simple experiment designed to test a hypothesis. Note that hypotheses can generally be worded as “if-then” statements. The “if” part of the statement is the independent variable (in this case, the change in teaching method); the “then” part is the dependent variable (in this case, the grades obtained by members of the experimental group).
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CHAPTER 1Section 1.4 Sources of Psychological Information
have no way of determining whether outcomes might have been identical without any experimental treatment.
Note that if the results of an experiment are to be applied to a large population, it is essential that the groups involved (the sample) be representative of the larger group from which they are drawn (the population). As we see later, one way of ensuring representa- tiveness is to sample randomly from the general population.
Ex Post Facto Studies
There is an important distinction between a true experiment and what is termed an ex post facto study. In a true experiment, the investigator assigns subjects to experimental conditions, controls independent variables, and controls as many other related variables as possible. But there are many situations in which the experimenter does not have control over independent variables. For example, an experiment designed to uncover the contri- butions of smoking to lung cancer would require that the experimenter randomly assign participants to an experimental group who would be required to inhale cigarette smoke in a prescribed manner and over a specified period of time. Other participants, comparable to the experimental group in all relevant ways, would be required not to smoke. Clearly, there are ethical reasons why this experiment cannot be conducted.
In cases such as this, investigators often conduct ex post facto studies—literally, after the fact studies. These are studies in which participants are selected on the basis of differences that already exist among them, in terms of either dependent or independent variables. For example, instead of assigning participants to smoking or no-smoking groups, people who have a history of smoking or not smoking are selected and compared with respect to the dependent variable, cancer or no cancer. Alternatively, the investigator might begin by looking not at independent variables (smoking or not smoking), but at the dependent variable (cancer or no cancer) and then ask, “How many of those with cancer were smok- ers and how many were nonsmokers?” They might also ask, “How many without cancer were smokers or nonsmokers?”
Ex post facto studies are highly common in psychology, simply because investigators usu- ally don’t have control over many important independent variables such as social class, family composition, mother-infant interaction, where people live, whether they have pets in the home, and so on.
There is one important caution in interpreting the results of ex post facto research. Although these studies can establish the presence of relationships, they don’t provide evi- dence that one variable causes another. An ex post facto study might establish that there is a relationship between father absence in early childhood and delinquent behavior in ado- lescence, but it cannot prove that father absence causes delinquency because any number of other uncontrolled variables (for example, poverty, mother absence, family size, and so on) might be causally related. Only a carefully controlled experiment can provide suf- ficient evidence of causation.
For a comparison of research methods that differ in terms of who is observed, when, and how, see Table 1.2.
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CHAPTER 1Section 1.5 Cautions in Interpreting Psychological Research
Table 1.2 Common Types of Psychological Investigations
Who Case Survey, Experiment
A single individual is observed. More than one individual is observed.
When Longitudinal Cross-Sectional
The same individuals are observed at different times.
Different groups of individuals are observed at the same time.
How
Experimental Ex Post Facto
The experimenter controls relevant independent variables and assigns subjects to groups.
The experimenter selects subjects, but nei- ther assigns them to groups nor exercises control over independent variables.
What
Descriptive Experimental
Main goal is to describe the characteristics of what is being studied. May be archival (based on existing records), or can be based on surveys, interviews, case studies, longitudinal or cross- sectional research, or correlational studies.
Main goal is to look for causal links between independent and dependent variables.
1.5 Cautions in Interpreting Psychological Research
To what extent can we rely on an experiment such as the toothpaste study described earlier, assuming, of course, that the results were reported accurately? Should we all run and purchase armloads of the new toothpaste?
Would the results be affected, for example, if the control group had been selected from a small rural area where the drinking water is obtained from a questionably clean river whereas the experimental group all reside in an urban area where fluoride is added to the water? Would the results be affected if the dentists who examined the subjects were share- holders in the company that manufactures the new toothpaste and if they knew who was a member of the experimental group and who belonged to the control group? Is it impor- tant to know the number of cavities in the histories of members of each of these groups? These questions touch on various potential weaknesses of psychological research, includ- ing experimenter bias, sampling bias, and subject bias.
Experimenter Bias
An assortment of rats was divided among two groups of psychology students (Rosenthal & Fode, 1963). The students knew that psychologists had been successful in breeding strains of rats highly different in their ability to learn how to run through mazes—so- called maze-bright and maze-dull rats. In this experiment, one group of students was told that they had been given rats of the maze-bright variety; the second group had to be content with less intelligent rats. In point of fact, however, both groups received randomly assigned rats of presumably equal intelligence.
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Students were asked to work with these rats over a period of time and to train them in maze tasks. Amazingly, students who had been led to believe that they had bright rats reported considerably more success in training their rats. In addition, they thought the rats more cooperative, gentler, and generally more pleasant to work with than did stu- dents whose rats were labeled dull (see Figure 1.6).
This experiment was among the first of many that have illustrated what is termed experi- menter bias. It appears that the expectations of experimenters exert subtle and sometimes remarkable influences on their actual observations.
A similar investigation conducted with elementary school children also illustrates experi- menter bias (Rosenthal & Jacobsen, 1968). It involved telling teachers that some of their students had been identified as potential “bloomers.” “Bloomers” were described as stu- dents of average or below average achievement whose potential indicated they could
Low
High
Scores reported by researchers who were told they had “maze-bright” rats
Scores reported by researchers who were told they had “maze-dull” rats
Figure 1.6
How great a role does experimenter bias play in the results of experiments? The smaller rat represents lower scores reported by researchers who were told they had maze-dull rats. Those who thought they had been given the more gifted rats reported significantly higher scores.
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CHAPTER 1Section 1.5 Cautions in Interpreting Psychological Research
easily achieve at a much higher level. The experimenters led the teachers to believe that they had developed a test that enabled them to identify these students and casually let them see a list of these “bloomers.” Astonishingly, although the “bloomers” had been ran- domly selected, they performed better than other equally intelligent students.
There have been many replications of this investigation since 1968. Some have not supported the original findings (Wineburg, 1987), but many have, although not always with results quite so dramatic (Jacobs & Harvey, 2010; Rubie-Davies, 2010). It seems clear that on occa- sion the expectations of teachers can affect not only the achievement of their students, but also their performance on objective measures of intelligence as well as their general behavior.
One of the most effective and most common means of guarding against the influence of experimenter expectations is to ensure that those responsible for gathering crucial experi- mental data not know which subjects are members of experimental groups and which are not. In the toothpaste experiment described earlier, if the dentists examining the children didn’t know which children had brushed with the new toothpaste and which were mem- bers of the control group, experimenter expectations would not likely affect the conclu- sions of the experiment. Studies where neither the examiners nor the subjects are aware of who is in the experimental group are termed double-blind procedures. In a single-blind procedure either the subject or the examiner is unaware (“blind”).
Subject Bias
Several decades ago in the Hawthorne plant of the Western Electric Company in Chi- cago, two psychologists (Roethlisberger & Dickson, 1939) experimented with different ways of increasing productivity among a group of women workers. In successive experi- ments the women were asked to work for longer periods of time, for shorter periods of time, for long periods with short rest breaks, for short periods with long rest breaks, with bright illumination, with low lighting, with lights turned almost off, with bonuses, with- out bonuses, and so on. Strangely, it didn’t matter what the experimenters did: Production always seemed to increase.
More recent research has shown that this so-called Hawthorne effect is not always appar- ent or very significant (Chiesa & Hobbs, 2008). Nevertheless, the possibility that the out- come of an experiment may be affected by the fact that subjects know they are subjects still exists and must be guarded against. Participants are often anxious to please investigators; consequently, their responses may sometimes be misleading. To guard against this pos- sibility, subjects are often not told whether or not they are members of an experimental group (a single-blind procedure).
Sampling Bias
One of the most common weaknesses of many experiments has to do with inappropriate or biased sampling. There are two crucial criteria that should be met when selecting members of experimental and control groups. First, the subjects must represent the group to which the experimenters wish to generalize. Second, the experimental and control groups must be as similar as possible on all relevant variables at the beginning of the experiment.
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CHAPTER 1Section 1.5 Cautions in Interpreting Psychological Research
If the experimental group is significantly differ- ent from other groups, then the experiment will not provide information that can be generalized to other groups. Consider, for example, an experi- ment designed to compare the effectiveness of two teaching methods. If the experimenter intends to determine the relative effectiveness of these meth- ods for all students in a given school system, it is important that experimental and control groups be as similar as possible to all students in the sys- tem in terms of intelligence, achievement, motiva- tion, and other relevant variables. If subjects are selected from a school where students have higher intelligence test scores, the results of the experi- ment might not be valid for other students.
Problems regarding the representativeness of samples are most evident in large-scale surveys where the intention is to generalize to a major segment of the population. Political fore- casts would be highly unreliable if only one segment of the population were sampled. For example, it would be difficult to predict how a nation would vote if forecasts were based only on surveys of academic populations or truck drivers.
To ensure that the results of such a survey apply to the entire population, investigators might select their sample so that it matches the population in terms of as many relevant characteristics as possible—a process called stratified sampling. If 52 percent of the popu- lation is female, close to 52 percent of the sample should also be female; if 23 percent have college degrees, then about 23 percent of the sample should also have college degrees. Similarly, in an ideal situation, the sample must match the general population in terms of age, religion, socioeconomic background, geographical location, and so on.
Another way of ensuring that experimental groups are representative of a larger popu- lation is to use random sampling. Random sampling requires that all members of the population have an equal chance of being selected. Given this condition, if enough repre- sentatives are drawn from the population, there is a high probability that the experimen- tal group’s characteristics will be very similar to those of the entire population. In other words, if 23 percent of a population is male and 77 percent female, a large enough sample drawn randomly from this population should be close to 23 percent male and 77 percent female. By the same token, the sample should resemble the entire population in terms of average intelligence, racial background, and other variables that might be important. In most cases, experimenters can make sure that this is the case by comparing the sample to the population on important variables.
Unfortunately, random and stratified sampling are only possible when investigators have access to the entire population to which they want to generalize. In many cases, circumstances dictate that samples will be samples of convenience. For example, those who do research on aging seldom have access to a random or stratified sample of the entire aging population, but are instead limited to groups such as those made up of members of clubs, religious groups, or residents of care facilities. Generalizing from these conve- nient samples requires caution. The need for comparability of experimental and control
No matter how large the sample, if its characteristics are very different from those of the population, resulting con- clusions will not have general validity. This soccer crowd, for example, might be very different from the mass of humanity who stayed home.
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CHAPTER 1Section 1.5 Cautions in Interpreting Psychological Research
groups, and for representativeness of samples, is obvious in the toothpaste experiment. Suppose, for example, that the control group averaged 30 percent more cavities than the experimental group at the beginning of the experiment: Regardless of the effects of the new toothpaste, it would be reasonable to expect that the rate at which the children developed cavities would be higher among those who initially had more cavities. Simi- larly, if all children in the study were selected from a single area where dental care was exceptionally good—or exceptionally bad—the sample might be totally unrepresentative of a more general population. Deliberately or accidentally biased sampling can easily ensure that the results of an experiment will be totally invalid.
Other Problems of Psychological Research
Among other problems that face researchers, as well as those of us who look for truth among their conclusions, are those of honesty, memory distortion, and inadvertent con- ceptual distortion. Studies of drug use, for example, have often provided inconclusive and contradictory results, probably largely because admitting to drug use is like confessing to a crime. In studies such as this, the dishonesty of participants is a crucial factor that can do much to invalidate the results of research.
A related problem is that of having to rely on imperfect memories. Child development psychologists have had some difficulty establishing conclusively the average age at which children learn to walk, a problem related directly to the memories of their moth- ers. Unless the researcher is present whenever significant developmental events occur, or unless these events can be objectively recorded, reliance must be placed on the partici- pant’s memory or on that of someone else who observed the event in question. In either case, it is often wise to question the accuracy of results that are not obtained through direct observation.
And, as we saw earlier, another pitfall in psychological research relates to the correlation fallacy—the belief that if two variables are correlated, one must cause the other. There are at least two reasons why correlation cannot be used to justify cause-and-effect conclu- sions. One is that a correlation between A and B does not, by itself, provide evidence of the direction of causality. That is, even if the correlation reflected causation, we might not know whether A causes B or B causes A.
The second reason why correlation is not proof of causation is that a correlation between A and B does not answer the question of whether the reason for the correlation might be a third variable, C. For example, an investigation of people ranging in age from 2 to 22 might reveal a very high correlation between finger length and the ability to understand concepts in advanced calculus. That, of course, would not prove that having long fingers helps people understand calculus—nor that understanding calculus leads to an increase in finger length. Rather, it likely reflects the effects of a third group of variables related to changes that occur over time.
Research Ethics The use of both human and animal participants in psychological research is an emo- tional and controversial topic. It raises some important ethical issues relating to how
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CHAPTER 1Section 1.6 Philosophical Issues and Psychological Controversy
participants in experiments are treated. Many of the procedures used in earlier investigations— where, for example, animals were euthanized or human participants were deceived, coerced, or otherwise made to do things they would not ordi- narily do—are no longer acceptable. Some believe that there are no circumstances under which ani- mals should be harmed in the interests of science (Knight, 2008); others argue that when the poten- tial benefits are sufficiently important, animals might need to be sacrificed (Brody, 2001).
The American Psychological Association provides guidelines for the ethical treatment of animal and human participants in research (Ethical principles . . . , 2011; and Guidelines for Ethical Conduct . . . , 2011). With respect to animal research, these guide- lines stipulate that the research must have a clear, scientific purpose with positive potential benefits, that animal care must comply with strict regula- tions, and that every effort must be made to mini- mize animal pain and suffering.
With respect to research with human participants, guidelines require that the ethical acceptability of the research be reviewed; that all participants be made fully aware of all aspects of the research that might affect their willingness to participate; that they be completely free not to take part; and that participants be protected from physical and mental danger or discomfort.
Avoiding the Pitfalls Have you by now developed an image of psycho- logical researchers stumbling blindly among the
numerous pitfalls of scientific research, never knowing for certain what to believe? That image would be misleading: Well-trained researchers are usually acutely aware of poten- tial pitfalls; they can guard against falling into traps that might deceive the less wary.
1.6 Philosophical Issues and Psychological Controversy
The search for explanations of human behavior is based on a number of assumptions that direct that search and that—in a very real sense—validate many of the beliefs resulting from the search. The most basic of these assumptions are philosophical in origin, have been subjects of controversy and debate that continue unresolved to this date, and cannot be tested or examined completely objectively. If they could, they would not be
Because 100 percent of divorces begin with marriage, there is a high correla- tion between number of weddings and number of divorces. But it would be meaningless to say that weddings are an important cause of divorces—or vice versa. Such reasoning illustrates the correlation fallacy.
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CHAPTER 1Section 1.7 Psychology’s Relevance
assumptions (which are, by definition, unproven) but would be laws or principles (beliefs more firmly grounded in objective observation).
Most important among these assumptions are those that deal with human nature and with the causes of behavior: Is behavior a function of free will, or is it determined by other forces? Are mind and body separate? Is behavior determined by underlying characteris- tics in the person (termed dispositions), or is it determined by the immediate situation?
Depending on the assumptions they make, some psychologists believe we exercise delib- erate control over our behavior; others are primarily deterministic: They believe behavior is an inevitable consequence of identifiable causes. Some look for the causes of behavior among genetic factors; others attribute a greater role to environmental forces. And the end result of the different assumptions psychologists make is that psychology is characterized by a number of different theories.
Psychology is a science that is sometimes gray rather than always black or white. Not all the pieces of the puzzle have yet been discovered or assembled.
1.7 Psychology’s Relevance
What do you want out of psychology? The question is not as simple as it might be in other fields. A bookkeeping course might teach you how to keep books; a course in dentistry, how to be a dentist; and a course in mathematics, how to do mathematics. But a course in psychology is not likely to teach you how to do psychology. Besides, what is involved in “doing” psychology is not at all clear. Clinical psychologists “do” psychology in one sense: They attempt to apply what they have learned or discovered to alleviate mental and emotional problems. Experimental psychologists also “do” psychology, but the thing they do is clearly different from the things done by clinical psychologists. A col- lege professor “does” psychology; but that too is different. In any case, you will probably not do any of these things as a result of this single course.
What then? Is psychology going to reveal the grand mysteries of the human psyche, expanding your understanding of yourself and of humanity? Will it enable you to func- tion better as a human being, directing you along paths of growth and happiness?
To some extent, yes. After all, psychology has enormous applications in a tremendous variety of areas. Psychology’s insights can make you a better parent, a more memorable teacher, a startlingly effective salesperson. Psychology can help you understand why you feel and act as you do, how your friends and family affect your behavior, and why you are moved to do certain things and do your utmost to avoid others. Advances in our knowledge of brain structures and functions suggest new approaches for treating addic- tions; increased understanding of how our sensory systems work has led to more effective treatments for sensory problems. Psychology gives us insights into how memory can be improved and maintained as we age. And it suggests highly effective ways of dealing with mental and emotional disorders.
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CHAPTER 1Section 1.8 This Book
1.8 This Book
In a very real sense, the remaining chapters of this book are a definition of psychology. That definition takes the form of a division of psychological topics into chapters, each dealing with a different facet of human behavior, and each attempting to summarize and interpret what is known about that aspect of behavior.
Following this introduction, we move to a consideration of our biological aspects: brain structure and functioning (Chapter 2) and sensory systems and perception (Chapter 3). Chapter 4 looks at how we learn, and Chapter 5 examines memory and thinking as well as intelligence. Chapter 6 is concerned with motivation and emotion: Why do we do certain things and not others? What moves us? In Chapter 7, we look at the forces underlying the changes that occur between birth and maturity. Chapter 8 looks at human personality—the qualities that make each of us absolutely unique—and Chapter 9 looks at mental disorders and the therapies psychology provides for righting these disorders. Finally, the 10th chap- ter looks at social psychology: how we relate to each other, how and why we fight and love.
The breadth and substance of psychology are evident in this arrangement of topics; and its definition, too, is implicit in them. That definition can be reduced to a single outline, as in Table 1.3, or can be reduced even further to a single statement that bears repeating: Psychology is the science that studies behavior and mental processes.
Table 1.3 An Outline of This Text as a Definition of Psychology
Chapter Outline Definition
1. The Science of Psychology Psychology is the science that studies behavior and mental processes.
2. The Brain and Consciousness Looks at the physiological basis of behavior and at our differ- ent states of consciousness.
3. Sensation and Perception Examines our sensory and perceptual systems, which are our sources of contact with the external and internal world.
4. Learning Asks how we learn.
5. Memory and Intelligence Investigates how we remember and studies the intellectual processes that our intelligence makes possible.
6. Motivation and Emotion Looks at the reasons for our behavior—at our motives and emotions.
7. Human Development Is concerned with the significant changes that transpire between birth and death, and with the forces that drive these changes.
8. Personality Examines human individuality and tries to understand how each of us is different and unique—and at the same time, how we share certain characteristics that define our humanity.
9. Psychological Disorders and Therapies Tries to understand mental and emotional disorders and searches for therapies to alleviate them.
10. Social Psychology Looks at relationships among individuals and at the enormous power of social influences.
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CHAPTER 1Main Points
It is important to note that even though our con- sideration of human behavior and thinking—the subject of psychology—is divided into separate topics, in the end, it is less the individual topics in which we are interested than the whole: We should not lose sight of the fact that the puzzle psychol- ogy is gnawing at involves the entire person.
Main Points 1. What Is Psychology? Psychology is
concerned with all that affects human behavior, thought, and emotion: It is the science that studies behavior and mental processes. About half of all psychologists are clinical psychologists; other divisions include counseling, industrial/organiza- tional, school, educational, developmental, experimental, and many others.
2. The Beginnings of Psychology: Psychol- ogy had its origins in Greek philosophy (psyche is Greek for “soul”; logos, for “study”), was profoundly affected by medi- cal discoveries, and borrowed its scientific methodology from Newtonian phys- ics. Its more recent origins date to Wundt’s psychological laboratory (1879) and his followers who established the structuralist school, William James’s functional- ism, Watson and Skinner’s behaviorism, Freud’s psychodynamics, and the influences of cognitivism and humanism.
3. Principles of Science: Science is an attitude that insists on precision and repli- cability, as well as a collection of methods to maximize the validity of conclu- sions. The five steps of the scientific method are (1) ask the question; (2) develop a hypothesis; (3) collect observations; (4) test the hypothesis; and (5) reach and share a conclusion.
4. Sources of Psychological Information: Observation is the source of knowledge in all sciences. Psychological investigations can be descriptive (describe charac- teristics of individuals or groups) or more experimental. Longitudinal studies look at the same individual(s) at different times; cross-sectional studies look at different groups at the same point in time. Descriptive research can be based on observation that occurs in natural surroundings (naturalistic) or in more con- trived environments such as laboratories. It can be based on observations of a single individual or unit (a case study) or of larger groups (a survey). Correlational studies try to discover relationships between variables but cannot prove causa- tion (the correlation fallacy). Experiments allow investigators to control independent variables to determine their effects on dependent variables. In an ex post facto study, investigators don’t assign participants to groups and don’t manipulate indepen- dent variables.
5. Cautions in Interpreting Psychological Research: Single-blind and double- blind procedures (where the examiners, the subjects, or both don’t know who
It’s a complex puzzle psychology is working on. These researchers are mistaken if they think it involves only the head.
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CHAPTER 1Main Points
members of the experimental group are) are used to safeguard against experi- menter and subject bias. To be able to generalize findings, the experimenter must study a sample representative of the population to which generalizations are to be made (often randomly selected for that reason). Psychological research can also be affected by problems of subject dishonesty, memory distortions, conceptual confusion, and the tendency to assume that if two events are correlated, one must have caused the other.
6. Philosophical Issues and Psychological Controversy: Psychological research is based on a number of sometimes controversial assumptions (nature vs. nurture, determinism vs. free will). The end result is a number of different theories and beliefs about human behavior.
7. Psychology’s Relevance: Psychology’s primary goals are to explain human behavior, to make increasingly accurate predictions, and to achieve a greater degree of effectiveness in alleviating human distress and in enhancing the joy- ful aspects of living. Not all the pieces of the puzzle have yet been discovered or assembled.
Study Terms
archival research
assumptions
average
behaviorism
bubba psychology
case studies
clinical psychologists
cognitivism
control groups
correlation
correlation fallacy
correlational research
counseling psychologists
criteria
cross-sectional studies
dependent variables
descriptive research
deterministic
developmental psychologists
double-blind procedures
educational psychologists
evolutionary psychology
ex post facto study
experiment
experimental group
experimental psychologists
experimenter bias
functionalism
generalize
genomics
Hawthorne effect
humanism
humanistic psychology
hypotheses
independent variables
industrial/organizational psychologists
introspection
longitudinal studies
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CHAPTER 1Main Points
naturalistic observation
neuroscience
nonnaturalistic observation
philosophy
population
psychiatrists
psychoanalysis
psychodynamic
psychology
random sampling
sample
school psychologists
science
scientific method
significant
single-blind procedure
statistical procedures
stimulus
stratified sampling
structuralism
surveys
synesthesia
theories
third force psychology
variables
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2
The Brain and Consciousness
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • What are the principal biological advantages
and disadvantages of humans relative to other species? • What are the main components and functions of nerve cells? • How do the most important neurotransmitters relate to behavior? • How is the human nervous system organized? • What are the key brain structures and their functions? • How are biology and behavior related? • What is the nature and purpose of sleep? • What functions might dreams serve? • Is hypnosis a distinct state of consciousness?
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CHAPTER 2The Brain and Consciousness
Drinking without being thirsty and
making love at any time, Madame,
are the only things that distinguish us
from other animals. —Pierre-AugustinCaronde
Beaumarchais,The Marriage of Figaro, Act2,Scene21,1784
Chapter Outline
2.1 Evolution Early Homo Sapiens
2.2 The Neuron Neural Transmission
2.3 Organization of the Nervous System The Endocrine System
2.4 The Brain Studying Brain Functions Structures of the Brain
2.5 Biology and Behavior Consciousness
2.6 Sleep Circadian Rhythms Stages of Sleep Why We Sleep Dreams
2.7 Hypnosis Some Facts Is Hypnosis a Different State of Consciousness? Applications of Hypnosis
2.8 Drugs and Consciousness
No, Monsieur de Beaumarchais, these are not the only things that distinguish us from other ani- mals. And perhaps we are not, in all ways, the superior animal we flatter ourselves on being?
Take a bat, for instance: Many people think bats are blind, which they really are not. But their vision is not very good: It does not have to be. Spallanzani, an Italian priest, was fascinated by how bats seemed to be able to fly hectically about at what must be, for a bat, breakneck speed. Yet they never seem to break their necks on houses or trees even when they fly in the dark. When Spallanzani released blinded bats in a room crisscrossed with tiny silk threads, the bats zipped around the room without ever running into the threads. But when he plugged their ears, they smacked into every- thing in their way (Dijkgraaf, 1960).
We now know that as they fly, bats emit a series of high-pitched squeals that bounce predictably off the objects they encounter. Since sound travels at a relatively constant speed, it is a small trick for the bat to compute how far the sound has traveled to an object and back again. A small trick, but one that we humans find exceedingly difficult. Our echolocation capabilities are pretty limited compared with those of the bat.
The bat is not the only animal that is, in at least one sense, superior to us: Bears and dogs and even penguins can detect odors that we cannot; a golden eagle can, on a clear day, spot a green frog swimming in green water six inches below a murky green surface; the grizzly bear is physically stronger than we are; the antelope, faster; the dolphin, a more graceful swimmer.
The point is that we, and all other animals, behave as we do largely because of our different physi- ologies and our different nervous systems. Some of the pieces of the human puzzle are to be found in our “wiring” and its functioning.
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CHAPTER 2Section 2.1 Evolution
2.1 Evolution
We are Homo sapiens, the self-named wise one—a seemingly appropriate label given our well-developed “new” brains, our opposable thumbs, the fact that we walk upright, and our ability to communicate through the use of arbitrary symbols.
But we don’t have clever thumbs just because we decided they would be an advantage; we did not invent our brains; we made no conscious decision to shift from a four-legged to a two-legged form of locomotion, thereby making our front legs obsolete and even- tually changing their names to arms; nor did we, in council one day, decide that a lan- guage would be superior to the grunts and gestures we might previously have been using. Most scientists believe these revolutionary happenings resulted from evolution, although some believe they were the products of an inventive Supreme Being (creationism). Others think both explanations are valid—that evolution describes the progression of the species whereas creationism describes its origins. The issue cannot be resolved here, although we will wander briefly back into the murky depths of evolutionary history.
Evolution, the adaptive progression of species from their origins, might at first glance seem an inappropriate topic for a study of human behavior. We are, after all, concerned with understanding our current behavior. But perhaps something in evolution might help our understanding. Certainly, much in our behavior is related to biology; and much of our biology seems to be the product of evolutionary processes.
Early Homo Sapiens
Much of the evidence upon which the early details of evolutionary theory are based is drawn painfully from the few records nature has haphazardly provided: a fossil here, a bone there, a fragment of skull, a petrified dinosaur dropping. More recently, the study of change at the level of genes—termed molecular genetics—provides another rich source of information.
Those who peer back into the dimness of geological time, and those who study changes in genetic material over time, inform us that very primitive tool-making humans made their inconspicuous appearance on this planet approximately 2 million years ago. Widely accepted speculation has it that three species of humans evolved over the next million or so years: Homo habilis followed by Homo erectus, then Homo sapiens (Spoor et al., 2007). We, Homo sapiens, are thought to have appeared less than 200,000 years ago, give or take a hundred thousand years (Elert, 1997). We are now the only remaining species of humans in a world comprising approximately 1.5 million other species (Osborn, 2010). We belong to the primate order, of which there are over 300 living species (Primate Gallery, 2010). Our class is mammal, which belongs to the chordate phylum in the animal kingdom (Figure 2.1).
Not only did Homo sapiens survive, but the species thrived, although numbers grew very slowly at first, requiring more than 100,000 years to reach the first billion. This happened around 1800, but the second billion was reached in only around 100 years, and the next 100 years saw an increase of nearly 5 billion (U.S. Census Bureau, 2010a) (Figure 2.2).
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CHAPTER 2Section 2.1 Evolution
In some ways, it is astonishing that our species of humans survived, as defenseless as we were against the fangs and claws of the large carnivo- rous predators of those prehistoric times. We are a relatively slow species, endowed with unexcep- tional hearing and with a laughable sense of smell compared with that of many other species. Also, we are inadequately protected against both heat and cold, awkward at climbing trees or digging holes, clumsy in the water relative to dolphins, and incapable of flight without artificial means.
But we are more intelligent! If we could not out- fight or outrun a prehistoric enemy, we might yet outwit the beast. We could also stand upright. And while this did not make us as fast as most four-legged animals, it freed our arms and hands for purposes other than locomotion. We became an animal that could walk quite nicely on just two of its legs, freeing our arms for making tools, striking enemies while in full flight, gesticulat- ing, and blowing the nose, an undertaking that was not at all hampered by the fine opposable thumb that we now take so much for granted.
Useful though they may be for a vari- ety of purposes, our fine opposable thumbs aren’t our biggest evolutionary advantage: Our enormously complex brains are.
General Classification
Species
Genus
Family
Order
Class
Phylum
Kingdom
Human Classification
Homo sapiens
Homo
Hominidae
Primate
Mammal
Chordate
Animal
Fr o
m m
o st
g en
er al
to m
o st
s p
ec ifi
c
Figure 2.1
Biological classification of humans. We are the only species left of the genus Homo. But there are more than 300 known living primate species in the world.
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CHAPTER 2Section 2.1 Evolution
Although many other primates also have opposable thumbs, no other animal can boast the manual dexterity that we have at our fingertips. And no other animal possesses as large and complex a brain as we have.
Brains, Language, and Thinking Eventually brains led to primitive tools, to agricultural and hunting implements, to the wheel, the rocket, the computer. But perhaps more important than all this, brains led to the development of language and of culture—and to the possibility of sharing informa- tion and even of transmitting it across generations. (Language learning among infants is discussed in Chapter 7.)
Thinking and language are very closely related. In fact, a school of thought that was widely popular among anthropologists a few decades ago maintained that language is essential for and determines thought—a belief labeled the Sapir-Whorf hypothesis. In its strong form, this hypothesis maintains that different languages lead people to see the world dif- ferently and to think and behave differently. For example, some early research suggested that the Inuit, who seemed to have many different words for snow, could actually per- ceive types of snow of which others were unaware. Similarly, cultures that had a different
World population in billions
P o
p u
la ti
o n
in b
ill io
n s
Year (AD)
1200 1400 1600 1800 2000
0
1
2
3
4
5
6
7
8
Figure 2.2
Approximate population growth for Homo sapiens on earth. The part of the graph to the left that is not shown would extend about 1 mile if it reached back to the time when humans first appeared. Based on World Population Prospects: The 2008 Revision Population Database, United Nations Population Division. Retrieved July 20, 2010, from http://esa.un.org/unpp/; U.S. Census Bureau, International Data Base, June 2010 update. Retrieved June 20, 2010, from http:// www.census.gov/ipc/www/idb/worldpopgraph.php
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CHAPTER 2Section 2.1 Evolution
vocabulary for colors were thought to see colors differently. These beliefs have now been discredited (Pullum, 1991). Experimental research has not supported the strong form of the Sapir-Whorf hypothesis (Koerner, 2000). It seems that language is not essential for thinking. For example, there is evidence of thinking among preverbal infants (Gleitman & Papafragou, 2005). And it is also true that adults sometimes think in terms of images or other symbols rather than with language.
Still, a weaker form of the Sapir-Whorf hypothesis is widely accepted. It argues that while lan- guage does not entirely determine thinking, it greatly influences how we think and accounts for some differences in the thought and perception of different cultures (Boroditsky, 2003).
As Newell (1990) explains, a symbolic representational system such as language is essen- tial for systematic reasoning and for sharing knowledge. Language is a fundamental force in defining human cultures and in shaping our lives. There is little doubt that language is one of the most important accomplishments of the brain.
Evolution and the Nervous System The brain is part of our nervous system. In a simple sense, our nervous system is the elec- trical and chemical communication system within our bodies. It is because of our nervous system that our right hand knows what our left hand is doing, that our legs alternate rather than compete when we walk, that we are sensitive to our environments. In fact, it is because of our nervous system that we can even think about such matters; hence its tremendous importance in psychology.
In an evolutionary sense, our nervous system is among the most complex and highly developed of all animals. It stands in sharp contrast to that of more primitive creatures. At the lowest level, for example, there are single-celled organisms whose responsiveness is highly limited. There are also simple multicelled organisms such as sponges whose various nervous systems are not in communication with one another. Parts of the sponge contain specialized cells for reproduction or secretion, each of these functions being car- ried out independently of what might be happening elsewhere in the sponge.
The nervous systems of insects also provide an interesting evolutionary contrast to those of humans. In some insects, primitive clusterings of nerve cells coordinate simple functions, such as its brain telling a cockroach when and where to run (Bender, Pollack, & Ritzmann, 2010). But in many insects, there is no single “command area”—no brain to oversee all func- tions or to be aware of what is going on in all parts of the body. Cut off the head of a wasp and it will continue eating even though it has lost its abdomen and there’s nowhere for the food to go. In much the same way, the male praying mantis will continue to copulate even as the female systematically devours him from the head down (Prokop & Vaclav, 2008).
The more advanced nervous systems of fishes, reptiles, and mammals differ from these more primitive nervous systems. Not only is their functioning more complex, but their activity is coordinated by an increasingly large brain. Furthermore, brains in more advanced animals have become highly specialized: A large portion of the bat brain is devoted to hearing; the olfactory (smell) area of dog brains is far more developed than
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CHAPTER 2Section 2.1 Evolution
that of human brains; those parts of the brain that control rapid movement are more pre- dominant in bird brains; and in humans, the area of the brain devoted to thinking is larger, proportional to the remainder of the brain, than in any other living creature (Figure 2.3). It is this brain, the command center of our nervous system, that is largely responsible for what we are and for our behavior.
Figure 2.3
Homo sapiens may not see, hear, or smell as well as many other species, but greater relative brain size and the greater relative size of the “thinking” part—the association areas of the human brain—have given us an evolutionary advantage. Copyright Hungry Coyote Limited. Used by permission.
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CHAPTER 2Section 2.2 The Neuron
2.2 The Neuron
The human nervous system is a communication system; its function is to transmit mes-sages (impulses). Many of the messages it transmits go from sensory receptors (such as the skin, eyes, nose, tongue, ears, muscles, joints, and tendons) to the command center (the brain). Impulses also go from the brain to what are termed effectors (such as muscu- lar and glandular systems).
The cells that make up the nervous system, and whose specialized function is to transmit impulses, are called neurons (or nerve cells). Estimates vary widely, but scientists believe there are approximately 86 billion neurons in the human brain alone, with the bulk of these—some 69 billion—being in the part of the brain called the cerebellum (Azevedo et
receptors
effectors
sensory nerve fiber
connector
motor nerve
1
2
4
5
3
Figure 2.4
Schematic conception of the components of the sensorimotor arc. Receptors (1) in eyes, tactile organs, nose, ears, taste buds, and kinesthetic senses send signals (2) to connectors (3) in the spinal cord, brain, and other neural pathways. Signals are then sent (4) to effectors (5) in mus- cles and glands.
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CHAPTER 2Section 2.2 The Neuron
al., 2009). The spinal cord contains at least a billion more, and several billion more are concentrated in sensory receptors and in muscular and glandular effector systems. Other neurons are connectors: They serve as links between receptor and effector systems (Figure 2.4). Most of the connectors are located in the brain.
Like all other living cells, neurons consist of a nucleus and surrounding matter. This mat- ter is made up of the cell body, axons, and dendrites. Neurons are surrounded by a pro- tective coating, called a myelin sheath (made up of glial cells). The axon is the elongated part of a neuron: It may be microscopically short or as long as 2 or 3 feet, as is the case for some neurons located in the spinal cord. Dendrites are hairlike extensions emanat- ing from the cell body of the neuron. The space between the ends of one cell’s axon and another cell’s dendrites is a synapse. Enlargements found at the terminating ends of some axons are synaptic knobs. Bundles of neurons make up nerves. The typical configuration of a neuron is shown in Figure 2.5.
Neural Transmission
The transmission of impulses from neuron to neuron involves both electrical and chemi- cal activity. Think of each neuron as a tiny battery that can generate an electrical impulse.
Cell body
Myelin sheath
Nucleus
Axon
Synapse
Dendrites
Figure 2.5
Electron micrograph photo of human nerve cells magnified many times with their principal parts identified. Neural transmission typically proceeds from the cell body, down the axon, across the synapse, and to the dendrites and cell bodies of adjacent cells. Synaptic knobs at the terminating ends of some axons facilitate transmission of electrochemical impulses.
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CHAPTER 2Section 2.2 The Neuron
Electricity is the flow of negatively charged particles (called electrons) toward a positively charged pole. In the neuron, electrical impulses operate in exactly the same way. A neuron at rest (resting potential) is like a charged battery with the switch off. Stimulation brings about a series of chemical changes that effectively open the switch, causing a flow of charged par- ticles called an action potential. And about 2 milliseconds later, the neuron again regains its resting potential. But for a brief period, termed a refractory period, it is essentially dis- charged and so no longer has the potential to generate an electrical impulse (Figure 2.6).
Note that the electrical impulse involves the entire neuron and is equally strong through- out the neuron: hence the expression “all-or-none” firing. What this means is that an elec- trical signal that is generated in your toe when you stub it will not have dwindled away to nothing before reaching your brain. Unfortunately, however, the “pain” sensation will not reach your brain immediately. Although electricity travels at the speed of light (186,300 feet per second), the thinnest axons transmit impulses at only around 3 feet per second. Larger axons might transmit at speeds up to 10 feet per second (Kalat, 2009).
So, less than a second after you stub your toe, you will know that you did so, unless something has happened to disrupt the flow of electrical impulses in relevant nerves. That is basically what happens when your dentist uses novocaine to “freeze” you. Nothing is actually frozen, but the effect of the novocaine is to block the flow of electrical impulses between neurons. No matter how desperately the receptors in your tooth yell, “It hurts,” the message simply does not get to your brain.
+40
–70
0 1 2 3
Neural impulse
Refractory period
Resting potential
CBAM ill
iv o
lt s
Milliseconds
Figure 2.6
Representation of a neural impulse. At point A, there exists a state of readiness (resting poten- tial). At B, a stimulus leads to an electrical impulse (action potential), which is followed imme- diately by a refractory period during which the cell cannot fire. A few milliseconds later, the cell is restored to its resting potential (charged) state. As shown in the photo of the synapse, certain chemical substances, neurotransmitters such as dopamine and serotonin, play an important part in the “opening” of neural membranes to allow the passage of the electrical impulse.
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CHAPTER 2Section 2.2 The Neuron
Neurotransmission is made possible by cer- tain chemicals, called neurotransmitters, which are released by neurons, changing the electrical potential of cells and thus leading to neural trans- mission. These chemicals are then reabsorbed by the releasing neuron—a process referred to as reuptake.
Of special interest in the treatment of a variety of emotional and physical disorders are drugs that have been developed to increase or impede the functioning of the neurotransmitters. Agonists increase the effectiveness of neurotransmitters, either by stimulating neurons to produce more, by increasing the sensitivity of receptor cells, or by preventing the reuptake of the neurotransmit- ter, thus making more available. Antagonists block or reduce the effects of a neurotransmitter.
Of the more than 100 different neurotransmitters that have now been identified, 4 are especially important in the study of psychology: dopamine, norepinephrine, acetylcholine, and serotonin.
Dopamine Dopamine is key to the functioning of neurons associated with pleasure and reinforcement. In fact, almost all abused drugs are effective pre- cisely because they increase dopamine activity in certain areas of the brain. Some research indicates that individuals who normally have low levels of dopamine are more likely to become addicted (for example, Asensio et al., 2010; Self & Staley, 2010). And in some cases, there appear to be genetic differences between addicts and nonaddicts related to this neurotransmitter (Levran et al., 2009).
A disease associated with low dopamine levels in areas of the brain where dopamine is usually most concentrated is Parkinson’s disease. It is characterized by shaking, general- ized weakness, slow movements, constipation, sleep disturbances, and depression.
Norepinephrine The neurotransmitter norepinephrine (also called noradrenaline) increases blood pressure and triggers the release of glucose (sugar) from energy stores. Consequently, it is the neu- rotransmitter most closely linked with crises. In an emergency, parts of the brain are sud- denly flooded with norepinephrine, a signal that prepares the body to respond, perhaps by fleeing, perhaps by fighting.
Almost all abused drugs are effective because they increase the release of dopamine in the brain or prevent its reuptake. Dopamine function is a key to reinforcement and pleasure. Chocolate too, as this lad well knows, is associated with dopamine and other neurotrans- mitters linked with reinforcement.
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CHAPTER 2Section 2.3 Organization of the Nervous System
Research indicates that norepinephrine levels may be implicated in some instances of attention-deficit hyperactivity disorder (ADHD) (Bhaduri, Sarkar, Sionha, Chattopad- hyay, & Mukhopadhyay, 2010). One of the effects of drugs (such as Ritalin) commonly used to treat ADHD is that they act as norepinephrine/dopamine reuptake inhibitors, increasing available levels of norepinephrine and dopamine (Cohen-Yavin et al., 2009). This improves the person’s ability to concentrate and to think clearly about what is being focused on, thus alleviating one of the main symptoms of ADHD.
Some manifestations of depression are also linked with norepinephrine. Many common antidepressant drugs (for example, tricyclic antidepressants such as Elavil, Norpramin, and Pamelor) are agonists that increase norepinephrine levels by blocking its reuptake (Craig, 2006). One of the effects of increased norepinephrine levels is a speeding up of neural activity, which counters the “slowing down” sensation that often accompanies depres- sion. Interestingly, an overabundance of norepinephrine has been linked with mania, the opposite mood to depression (Narayan & Haddad, 2011).
Acetylcholine Acetylcholine is a neurotransmitter involved in the largely unconscious functioning of the autonomic nervous system (concerned with functions such as heart and respiration rate). It is also importantly involved in conscious activity such as muscle movement, as well as in arousal, reinforcement, learning, and memory (Arnulf & Leu-Semenescu, 2009). It can also serve to increase the reactivity of neurons or to inhibit their responsiveness. Drugs that stimulate the acetylcholine system or that block its functioning have a variety of medical uses, including the treatment of Alzheimer’s disease (Zhang et al., 2010).
Serotonin Serotonin is involved in neural transmission in much of the brain, especially in areas hav- ing to do with emotion. Its other functions include regulating sleep, appetite, and cogni- tive activity related to learning and memory (Pothakos et al., 2010). Depressed levels of serotonin have been linked with depression, aggression, and even violence. Accordingly, many antidepressants and anti-anxiety drugs are agonists that affect serotonin levels by acting as reuptake inhibitors (Arnone, Horder, Cowen, & Harmer, 2009). Similar drugs are also sometimes used to control impulsive, violent behavior (Butler et al., 2010).
Serotonin is present in some plants and seeds, including nuts from some walnut and hick- ory species, many of which are toxic or at least cause pain. In fact, pain is one of the side effects of large amounts of serotonin in the blood. Interestingly, wasp, toad, and stingray venoms contain serotonin, which serves to increase the painfulness of their stings (Fevzi, Ergin, Rivers, & Gençer, 2006; Ling, Clark, Erikson, & Trestrail, 2001).
2.3 Organization of the Nervous System
The central nervous system consists of the brain and spinal cord. It is via the spinal cord that most of the major neural pathways conduct impulses between brain centers and various glandular, muscular, and sensory systems.
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CHAPTER 2Section 2.3 Organization of the Nervous System
The system of neural networks that fan out from the central nervous system into various parts of the body is the peripheral nervous system (Figure 2.7). The peripheral system is linked to all sensory organs and to the muscles and glands; it is also involved in physi- ological activities such as respiration, heart action, sweating, and crying.
The peripheral nervous system has two divisions. The somatic system transmits impulses relating to sensations of heat, cold, pain, and pressure to the central nervous system. It also transmits impulses in the opposite direction, from the central nervous system to muscles involved in voluntary movement.
The autonomic nervous system, the other part of the peripheral nervous system, is directly involved in the action of muscles and glands that are automatic and involuntary. It includes the sympathetic nervous system, which is responsible for mobilizing the body’s resources, particularly in emergency situations. It is your sympathetic nervous system that causes adrenaline to be pumped into your system. The result is that your heart beats faster, blood rushes through your blood vessels, and you might tremble in anxiety, blush in shame, or respond with any of the other physiological changes that accompany intense emotion.
Most of us have little control over our physiological reactions, a fact that led to the inven- tion of the common lie-detector. This instrument is capable of detecting changes that result from activity of the autonomic nervous system. If you become anxious when you lie (as most people do), your sympathetic nervous system reacts accordingly. As a result, your
Central nervous system
(brain and spinal cord)
Autonomic (unconscious activity of
muscles and glands)
Somatic (physical sensations such as pain, heat; skeletal muscles)
Parasympathetic (conserves resources; reduces
norepinephrine; slows heartbeat; constricts pupils, etc.)
Sympathetic (emergency action: norepinephrine
build-up; speeded heartbeat; dilated pupils, etc.)
Peripheral nervous system
a b
Figure 2.7
The human nervous system. Part a depicts the two major divisions of the nervous system: the central nervous system (bright orange) and the peripheral nervous system (darker). The orga- nization and functions of each are described in b.
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CHAPTER 2Section 2.4 The Brain
palms perspire, your breathing changes, and your heart rate increases.
But your heart rate does not accelerate indefi- nitely, nor do you tremble more and more vio- lently. The parasympathetic nervous system, the other part of the autonomic nervous system, slows your heart rate, steadies your trembling, increases your control over bowel and bladder functioning, and in other ways opposes some of the functions of the sympathetic nervous system. It is as though the parasympathetic nervous sys- tem serves to conserve bodily resources.
The Endocrine System
The endocrine system is separate from the cen- tral nervous system, but it influences most of the organs, cells, and functions of the body. It includes glands that secrete hormones directly into the bloodstream and are therefore known as the ductless glands. Chief among them are the pituitary gland, which is frequently termed the “master” gland because of its role in regulating activity of other glands. The ductless glands also include the adrenal glands and the gonads.
The adrenal glands, which sit on top of the kidneys, are mainly responsible for releasing the hormone adrenaline in response to stress. The gonads include the testes, which pro- duce male sex hormones such as testosterone, and the ovaries, which produce estrogen in females. As we see in Chapter 7, these hormones are involved in sexual maturation and in sexual motivation.
2.4 The Brain
The most important part of our central nervous systems is our brain, which is reput-edly the single most complex structure in the entire known universe. We have known for some time that this unimpressive-looking lump of grayish tissue is at the very center of our ability to learn, to feel, to think—that it determines and defines our very essence. But we did not always know this. In fact, the ancient Egyptians considered the brain so unimportant that they did not bother to preserve it in their mummies, removing it instead through the left nostril (Blakemore, 1977). It is only recently that the secrets of the struc- tures and functions of our brains have yielded new pieces for our puzzle.
Studying Brain Functions
September 13, 1848, was an unlucky day for Phineas Gage, a railway worker on a rail line in Vermont. On that day, a tamping rod measuring 3 feet, 7 inches, shot out of a blasting
When we’re anxious, as might happen when we lie to a police investigator, our sympathetic nervous system kicks up our heart rate, our palms perspire, and our breathing changes. We can’t control these reactions, and the “lie- detector”—a polygraph that measures these changes—reveals our lie.
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CHAPTER 2Section 2.4 The Brain
hole and went through the left side of his face, through his brain, and out the top of his head! The blow hurled him to the ground, but he quickly picked himself up, made his way to a cart, and went home.
Phineas’s physical recovery was rapid and apparently complete. But some reports claim that he was never again the same man, that he became moody and selfish and prone to outbursts of violent temper. His physician, Dr. John Harlow, and a Harvard surgeon named Dr. Henry Bigelow concluded that the part of his brain that was affected had to do with emotions and personality (Macmillan, 2000). In fact, brain injuries provided one of the first ways of trying to discover how the brain works.
Unfortunately, as Macmillan (2008) points out, no one ever examined Phineas Gage’s brain directly, so there really is no certainty about what structures were involved in his injury. Also, there seems to have been some exaggeration and contradiction in reports of his case: There is a strong likelihood that he did not change as dramatically as has sometimes been reported. And the fact that he later began to suffer seizures and eventually died as a result might indicate that his recovery was far from complete.
Brain Ablations The problem with studying the brain using injuries such as those caused by tumors or by accidents is that these injuries don’t usually have very specific effects. They often affect large parts of the brain, and investigators certainly cannot control who will have an acci- dent—which makes for poor research.
Another approach is to deliberately cut out small portions of the brain and then see what the effects might be. Understandably, this kind of research finds very few volunteers with healthy brains. Except where surgical procedures are required in cases of brain damage, epi- lepsy, tumors, or for other medical reasons, most of this research has been done with animals.
A pioneer researcher in this area, Karl Lashley (1924), taught some rats how to run through a maze. He was convinced that different memories leave a trace in a tiny part of the brain, and he thought that if he cut out just the right part, the rat would no longer remember how to get through the maze. But Lashley never did find this memory trace (called an engram). It did not seem to matter what part of the brain he excised, or how much; the rat continued to run through the maze—although sometimes much more slowly. We now know that the kind of memories Lashley was studying were likely stored in parts of the brain he did not excise.
Brain Stimulation Another way of studying the brain is to stimulate different parts of it with electrodes or with chemicals. For example, Olds (1956) implanted electrodes in the brains of rats and acciden- tally discovered that stimulating part of the hypothalamus—now labeled the “pleasure cen- ter”—seemed to be extremely pleasurable for the rat. When the electrodes were connected to a lever so that rats could stimulate their own brain, many would pass up food to do so. One rat stimulated himself more than 2,000 times an hour for 24 consecutive hours!
Stimulating the brain with electrodes is an invasive and difficult undertaking; chemical stimulation is much simpler. It is possible to administer different drugs (chemicals) and
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CHAPTER 2Section 2.4 The Brain
to observe their effects on the participant’s behav- ior and their effects on the brain. For example, chemical stimulation of the brain reveals that the neurotransmitter dopamine is involved in neural activity associated with pleasure. Dopamine, as we saw, is a naturally occurring neurotransmitter. Normally, when it is released as a result of neural stimulation, it is quickly recaptured by affected neurons (Kalat, 2009). But certain drugs such as amphetamines and cocaine act as agonists by pre- venting the immediate reuptake of the dopamine so that dopaminergic neurons (those that use dopa- mine for neural transmission) stay active longer. Because dopamine is associated with neural activity in one of the brain’s “pleasure” cen- ters, the ultimate effect of cocaine is intensely pleasurable (Morcom et al., 2010).
The prolonged use of agonists such as cocaine, however, leads the brain to synthesize less dopamine naturally as it adapts to the drug. As a result, the chronic drug user often expe- riences depression and other negative moods rather than pleasure when the effects of the drug begin to wear off (termed withdrawal). Also, dopamine receptor activity decreases with repeated drug use (termed drug tolerance) so that ever-increasing amounts of the drug are required (Slomski, 2006). Tolerance and the presence of withdrawal symptoms are important indicators of addiction. (Drug use is treated in more detail in Chapter 9.)
Electrical stimulation of the brain’s pleasure centers, as well as natural reinforcers such as food, water, and sex and substances such as nicotine and alcohol, all lead to the release of dopamine (Lajtha & Sershen, 2010). And all of these substances and activities are poten- tially addictive.
Brain Imaging The effect of chemicals on the brain is usually detected by means of one or more of the vari- ous sophisticated brain-imaging techniques researchers now have at their disposal. These include the electroencephalogram (EEG), which provides recordings of brain electrical activ- ity; positron emission tomography (PET), which records changes in blood flow by respond- ing to radioactive particles injected in the bloodstream; functional magnetic resonance imaging (fMRI), which measures changes in magnetic fields related to blood oxygen level; and magnetoencephalography (MEG), which detects at the scalp incredibly small changes in magnetic fields associated with neural activity. Note that these brain-imaging methods are used not only to study the effects of drugs, but also to look at brain activity during specific tasks. They are highly useful in studies of the brain’s role in intellectual activities.
Structures of the Brain
Physical examination of the brain reveals a grayish mass inside the skull (Figure 2.8). Some of its various structures are identifiable through this type of examination. But deter- mining the functions of these structures is not so simple: The structures themselves pres- ent few clues to their functions.
Electroencephalograms (EEGs) provide a nonintrusive way of studying brain functioning.
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CHAPTER 2Section 2.4 The Brain
Figure 2.8
Top, right side, and under side view of the human brain. The outer covering of the brain is called the cerebral cortex.
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CHAPTER 2Section 2.4 The Brain
Hindbrain As shown in Figure 2.9, the human brain is normally divided into three basic parts: hind- brain, midbrain, and forebrain. These parts are thought to have evolved in that order, with the hindbrain being the oldest structure and the forebrain the most recent. Structures of the hindbrain and of the midbrain make up the brain stem—that part of the central ner- vous system that connects the spinal cord with higher brain structures.
The hindbrain is the lowest part of the brain in an upright person. It consists mainly of the cerebellum (the word means small brain), the medulla, and the pons.
Cerebral cortex sensation, language, speech, thinking, and motor activity
MidbrainForebrain Hindbrain
Brainstem
Limbic system
Thalamus: “relay” center for sensory information
Hypothalamus: regulation of endocrine gland activity relating to growth, sexual behavior, and other functions
Pituitary: growth; regulation of other endocrine gland activity
Amygdala: emotion, aggression, memory
Hippocampus: learning and memory
Cerebellum: control of rapid and habitual movements; coordination of motor activity; balance
Pons: sleep and arousal; regulation of movement; respiration
Medulla: physiological functions such as breathing, heart function, digestion
Reticular formation: arousal center; sleep- wake control
Figure 2.9
A sagittal (bisected front to back) view of the human brain showing major structures and some of their principal functions.
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CHAPTER 2Section 2.4 The Brain
Interestingly, although it is a small structure relative to the rest of the brain, the cerebel- lum contains approximately 80 percent of all the brain’s neurons. Its main functions have to do with balance and timing and coordination of motor movements. It is also involved in the recall of skills and habits. Musicians and others who practice motor skills exten- sively often have cerebellums that are larger than average (Hutchinson, Hui-Lin, Gaab, & Schlaug, 2003). Injury to the cerebellum can dramatically impair activities such as walk- ing, playing the guitar, or catching a ball.
The medulla is involved in physiological functions such as breathing, heart functioning, and digestion. And the pons, which takes the form of a bulge at the front of the medulla, serves as a link between the medulla and higher brain centers (pons means bridge). The pons is importantly involved in sleep, the regulation of movement, arousal, and respiration.
The Midbrain The midbrain includes the reticular formation, found on the upper part of the brain stem. This structure is involved in maintaining arousal, or degree of alertness and motivation. It also contains nerve fibers associated with physical movement. Associated nerves are dopa- minergic, meaning that the main neurotransmitter involved in their activation is dopamine.
The Forebrain The largest and most complex brain structure is the forebrain. It is also the most important structure for understanding human thought, behavior, and emotion. It includes the hypo- thalamus, the thalamus, and other structures of the limbic system, as well as the cerebrum and cerebral cortex.
The hypothalamus is a bean-sized structure near the top of the brain stem. It is mainly involved in regulating activity of the autonomic nervous system. In a sense, the hypothal- amus is a little like a thermostat in that it oversees control of body temperature, as well as hunger and thirst and sleep-wake cycles. It is also involved in reactions to stress, initiating the signals that lead to the release of adrenaline.
The thalamus is found between the midbrain and the cerebral cortex. Its main function is to act as a relay station for transmitting sensory signals to the cerebral cortex. All sensa- tions except those having to do with smell go through the thalamus. It is also involved in regulating sleep and consciousness.
The limbic system includes parts of the hypothalamus and various other structures such as the amygdala and the hippocampus. Generally speaking, these are structures involved in emotions. The hippocampus also plays an important role in long-term memory. Alzheimer’s disease and amnesia are both associated with damage to the hippocampus (American Academy of Neurology, 2009).
The largest and most complex of our brain structures is the cerebrum, which divides naturally into two halves, the cerebral hemispheres. Its outer covering, the cerebral cortex, is centrally involved in higher mental functioning. This covering is highly convoluted
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CHAPTER 2Section 2.4 The Brain
and deeply fissured, the fissures resulting in four natural divisions (lobes) in each of the hemispheres. As a result, there is a right and a left one of each of these lobes (Figure 2.10).
At the front of the cerebral cortex are the frontal lobes, which are involved in motor activ- ity as well as in higher thought processes. On either side are the temporal lobes, involved in language, speech, and hearing. The auditory cortex is the part of the temporal lobe con- cerned with hearing.
Just behind the temporal lobes are the parietal lobes, implicated in physical movement and in sensation and physical orientation. At the very back are the occipital lobes, involved in vision. The part of the occipital lobes involved in vision is referred to as the visual cortex.
It is important to note that the main tasks and responsibilities of each of these cerebral divi- sions are not very simple or clear. Most functions are carried out by more than one part of the brain. Note, too, that areas of these four lobes that are not involved directly in motor activity or sensation are nevertheless involved in higher mental processes such as thinking, remem- bering, learning, and speaking. These are referred to as association areas of the brain.
The Hemispheres Phineas Gage’s accident provided some of the first crude evidence that the brain might be differentiated into separate functions. There was other historical evidence as well. Paul
central fissure frontal lobe (motor activity; higher thought processes)
temporal lobe (auditory cortex, language, speech)
occipital lobe (visual cortex)
lateral fissure
parietal lobe (sensation)
Figure 2.10
A right-side view of the cerebral cortex with the four right lobes labeled. Although each lobe is associated with the functions indicated, the lobes are highly integrated in terms of structure and function.
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CHAPTER 2Section 2.5 Biology and Behavior
Broca, a neurologist, was sent a patient suffering from aphasia, a language disorder that we now know is linked to brain damage. The patient died within a few days and Broca performed an autopsy, discovering lesions in the left temporal lobe. The area of the lobe that was affected by these lesions is now known as Broca’s region. Subsequent research has established that aphasia may be linked to lesions that are almost always on the left side of the brain. Lesions in the right half of the brain rarely disturb either receptive or expressive language functions, particularly in right-handed individuals, leading research- ers to believe that language functions reside primarily in the left half of the brain in right- handed individuals and in most left-handed individuals (Holland et al., 2007).
There is evidence, as well, that the right hemisphere might be more involved with emotions as well as with music and art (Workman, Chilvers, Yeomans, & Taylor, 2006). These findings have led some to speculate that there are “right-brained” and “left-brained” individuals, distinguishable in terms of their major preoccupations and abilities. Thus, the “left-brained” would be expected to excel at verbal and logical tasks; the “right-brained” would be more artistic and more musical. This sort of speculation has led to the view that conventional edu- cation neglects the “right” brain because it emphasizes highly verbal, logical, scientific con- tent and neglects more artistic and musical content. Holistic education, designed to educate both sides of the brain, is sometimes advocated as a remedy for this situation.
Unfortunately, much of what passes for information in this area is speculation and exag- geration rather than fact (Bruer, 2006). There is enormous overlap in the functions of the cerebral hemispheres. Nor are the hemispheres highly exclusive in their specializa- tions. For example, although the left hemisphere is somewhat more involved in language production functions than is the right hemisphere, when the left hemisphere is injured, especially if the injury occurs early in life, the right hemisphere frequently takes over left hemisphere functions—a striking example of an important characteristic of the human brain: plasticity. Brain plasticity is also evident in patients who suffer motor and language problems after brain damage resulting from a stroke. These patients often recover much of their previous functioning as other parts of the brain take over (Lazar et al., 2010).
Recovery of lost brain function may also result from neurogenesis—the formation of new neurons. Although most neurogenesis occurs during the prenatal period, it also continues into adulthood (Reynolds & Weiss, 1992). The finding of adult neurogenesis contradicts a long-held belief to the contrary.
2.5 Biology and Behavior
The purpose of this chapter is not to make you an expert in human biology, but instead to show you that there is scarcely a subject of interest to the student of human behavior that does not implicate the nervous system and body. It is clear that the magnificent brain we have evolved, coupled with a somewhat insignificant body, has made certain things difficult for us and other things far more possible. Thus, we can design a computer but we struggle to climb a tree.
The contribution of biology to learning and behavior is the main theme of evolution- ary psychology, a theme well illustrated in the case of the “miser” raccoon and the
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CHAPTER 2Section 2.5 Biology and Behavior
“baseball-playing” chicken. These were 2 of some 6,000 animals carefully trained by the Brelands, students of the famous psychologist B. F. Skinner (Breland & Breland, 1961, 1966). Using their mentor’s theory of operant conditioning (Chapter 4), the Brelands trained a raccoon to pick up a coin and deposit it in a tin box and a chicken to pull a rubber loop that would release a capsule that it could then “bat” out of the park for a home run. This is what these animals were required to do for their food. They learned quickly and per- formed impressively.
But not all 6,000 trained animals continued to perform as they had been trained. The rac- coon began to take longer and longer to accomplish its task, often refusing to let go of the coin, instead rubbing it between its paws, sometimes dipping it in the box and taking it out again. And the chicken became so engrossed in pecking and scratching around that it seemed to forget all that it had learned.
That this should happen is no surprise to evolutionary psychologists. After all, washing food and scratching around is what raccoons and chickens do for their living. And when these very strong instinctive behaviors conflict with newly learned responses, the animal tends to revert to the biologically based tendency—a phenomenon labeled instinctive drift.
What instinctive drift illustrates is a biological constraint—a biological limitation on learning. For example, there are clear biological reasons why we do not make very good bloodhounds, you and I: We cannot tell the difference between the stench of a pheasant and the stink of a rabbit. In fact, we cannot even detect the odor of either unless they’re practically stuffed up our noses. But my pooch, on the other hand, has no such constraints: She has an olfactory sense that is perhaps a million times more powerful than mine.
Biology works in the other direction as well. You could say that my dog is prepared to learn to distinguish between the smell of a ripe cantaloupe and the smell of the faintest trace of an explosive or a drug in somebody’s backpack. I, on the other hand, am contraprepared to learn such a thing.
So what has biology prepared humans to learn? Language, for one thing. And taste aver- sions, for another. We know that people are “prepared” to develop powerful aversions to certain foods—which can be highly useful if you don’t want to poison yourself. In fact, most animals, including humans, will develop a strong taste aversion after a single expo- sure to food or drink that makes them ill. Similarly, some research indicates that children can acquire fear of snakes exceptionally easily (Öhman, Carlsson, Lundqvist, & Ingvar, 2007).
Evolutionary psychologists speculate that our evolutionary histories may explain other human behaviors, some of which are not especially helpful for our long-term survival (Weiss, 2009). The fact is that through most of our evolutionary history, we lived in highly threatening environments where we had to guard constantly against being devoured by predators and we had to forage and scrounge and fight other animals and other devel- oping humans for food and shelter and mates. So our brains evolved to adapt to vio- lent and hungry times. Unfortunately, suggest Mead, Beauchaine, and Shannon (2010), these brains become maladaptive in less threatening environments. Such brains, they argue, carry a higher risk of psychopathology, and perhaps a far higher risk of potentially
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CHAPTER 2Section 2.5 Biology and Behavior
catastrophic events such as terrorism and wars. Brains like ours, finely tuned to be aggressive and violent, may yet be adaptive among reptiles and other nonhuman animals; but for us, they are in some ways socially maladaptive (van Honk, Har- mon-Jones, Morgan, & Schutter, 2010).
There are other ways in which our evolved brains may now be maladaptive: You see, these brains evolved when the probability of ingesting too much fat or salt or sugar was laughably unlikely. Besides, a well-fed and well-rested animal is far more likely to survive a period of cold and priva- tion, and perhaps to outrun or outfight a preda- tor or a rival. As a result, when we stand before our fridges, it is as though our primitive brains whisper in our ears, “Eat! There might not be any tomorrow!”
So we eat even though, being human, we know there will be food tomorrow, and we know that neither dimetrón nor saber-tooth tiger is likely
to invade our bedrooms this night. It is because of these same, sometimes maladaptive brains that we can anticipate with such startling clarity, that we can plan for times that are yet to come, and that we can remember the past. And, not only do we remember the past and anticipate the future, but we are aware of so doing. We are conscious of our awareness and we can communicate this consciousness to others—as you and I are doing at this very moment.
Put simply, we have a mind made possible by our brain.
Consciousness
If a neurosurgeon were to crack open the thick bony casing that protects your brain, would he uncover your mind? Perhaps, although he would not really see it; all he would see is a grayish lump of matter. But he might well presume that your mind, your self-awareness, resides in complex patterns of billions of interconnections that have formed among the neurons in your brain. And he might speculate, as he looks at this chunk of tissue, that at this very moment chemical and electrical changes and impulses swarm through many of the intricate patterns of neural networks. And some of these impulses will be associated with thoughts and feelings that you are now having: They will define your own private state of consciousness.
Consciousness, like mind, is a term with many meanings. The two terms are very closely related. Mind refers primarily to activities of the brain such as thinking and feeling that result in a sense of self; consciousness refers to an awareness of self.
We evolved in violent and hungry times. We weren’t always sure there’d be food tomorrow. Now it’s sometimes hard to walk away from the fridge.
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CHAPTER 2Section 2.6 Sleep
In effect, there are two broad states of consciousness: sleeping and waking. In addition, there are altered states of consciousness such as might result from certain drugs or perhaps from hypnosis.
2.6 Sleep
Sleep, as you well know, is the state that ensues when you close your eyes and even-tually lose immediate contact with your environment. It ends when you regain awareness of external events. But that does not mean you are completely unaware of your physical environment as you sleep. As you lie precariously on your narrow bed, a dangerous height above your stone floor, you have little fear of falling. You casually assume that your body has some control over its movements during sleep and that it is responsive to signals indicating dangerous proximity to the edge of your sleeping plat- form. And if your baby cries in the middle of the night, you instantly awaken—strong evidence that you are not totally unconscious while you sleep, that part of your brain remains alert.
Circadian Rhythms
We seem to be biologically prepared to sleep at night and to be active during the day—a phenomenon labeled a circadian rhythm. Circadian rhythms are daily cycles in biologi- cal and behavioral processes such as sleeping, temperature change, and the production of melatonin. Melatonin is a hormone closely tied to the regulation of sleep. It increases in the evening and during the night and decreases during the day. Melatonin is sometimes used to treat sleep disorders (Zee, 2010).
Although our sleep-wake cycles seem to be closely tied to the rising and setting of the sun, that we generate our own cycles becomes clear when we find ourselves in latitudes that have more or fewer hours of daylight. Other things being equal, we continue to sleep for approximately the same length of time and at about the same time each day. Even when participants are kept in surroundings that provide no clues about day and night, circadian rhythms tend to adjust to periods very close to 24 hours (Gronfier, Wright, Kronauer, & Czeisler, 2007).
Stages of Sleep
When early sleep researchers observed sleeping subjects, they saw that sleep involves eye closure, reduction of muscle tension, reduction of heart rate, lowering of blood pres- sure, slowing of respiration rate, and a marked decrease in body temperature. They also noticed that people, and animals, don’t seem to sleep uniformly and consistently. Some- times sleepers breathe rapidly, moving and fidgeting as they sleep; at other times, breath- ing is regular and there is little twitching and jerking. Dogs, too, jerk and fidget and moan and even bark as they sleep. Based on these changes, researchers concluded that there are distinct stages in depth of sleep (Neubauer, 2009).
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CHAPTER 2Section 2.6 Sleep
More recently, EEG recordings and observations of eye movements below closed eyelids have led researchers to describe four stages of sleep based on changes in brain activity. These four stages are followed by a period of rapid eye movements (Figure 2.11).
EEG recordings indicate that when awake, the brain typically produces small, fast waves called beta waves (13 to 30 per second), but these become slower, changing to alpha waves (8 to 12 waves per second) as the individual relaxes. During Stage 1 sleep, different waves called theta waves (4 to 7 per minute) become evident, interspersed with spikes of rapid brain activity. Perhaps 10 minutes later, if not awakened first, the sleeper enters Stage 2 sleep, also marked by bursts of rapid brain activity called sleep spindles. Note that Stages 1 and 2 are very brief.
In Stage 3, body temperature and heart rate continue to decrease and delta waves (up to 4 per minute) begin to appear. These slow, deep waves are characteristic of Stage 4 sleep, often described as the deepest stage of sleep.
Now, interestingly, brain activity shows the sleeper regressing through stages 3, 2, and 1 before entering the stage of rapid-eye-movement sleep (REM sleep). It is during this stage that most of our dreaming takes place.
Alpha to Delta, Theta
drowsy
Beta Beta
Lose conscious control of muscular movements
Lose ability to hear sounds
asleep
Regain conscious control of muscular movements
Regain ability to hear sounds
Stage 1 Stage 2 Stage 3 Stage 4 Stage 1 REM
Eye movements
EEG (brain waves)
Awake Awake
Figure 2.11
Physiological changes during sleep. Stage 1 REM sleep is sometimes labeled Stage 5 sleep, although brain waves during this stage are identical to those of Stage 1 sleep. The difference is that during this stage the rapid eye movements that typically accompany periods of dreaming are observed.
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CHAPTER 2Section 2.6 Sleep
REM sleep (rapid eye movement) comprises between 20 and 25 percent of our normal sleep; non-REM sleep makes up the remaining 75 to 80 percent. There are some marked differences between these two sleep states, apart from their typical duration and the presence or absence of rapid eye movements. During REM sleep, physiological functions are very similar to those expected in a normal, awake person (hence this stage of sleep is often labeled paradoxical sleep): Heart rate ranges between 45 and 100 beats per minute, breathing is irregular, and EEG patterns are similar to those seen in quiet resting states with the eyes closed (alpha). However, voluntary muscle groups are typically in a state of paralysis
during REM sleep. There is speculation that this muscular paralysis is meant to keep the body from acting out violent dreams and possibly hurting itself.
In adults, REM sleep occurs fairly regularly at approximately 90-minute intervals and lasts for 25 minutes or more. It does not begin for 30 or more minutes following onset of sleep. If a person is awakened from non-REM sleep and kept awake for a few minutes, REM sleep will not begin for at least 30 minutes, even if the person had been in non-REM sleep for the last hour or more (Figure 2.12). Thus it is possible to deprive subjects of REM sleep simply by waking them whenever rapid eye movements begin. Similarly, it is pos- sible to deprive subjects of non-REM sleep. One of the results of this procedure is that subjects who are deprived of one type of sleep tend to make up for it during subsequent nights. A second effect of REM or non-REM deprivation is that subjects who are allowed only one type of sleep frequently feel and function as if they had not slept at all. It seems clear that we have a need for both types of sleep and that neither is more restful than the other in spite of the apparently greater reduction in rate of physiological functioning dur- ing non-REM sleep.
Why We Sleep
We still don’t know for sure why we must sleep (The Science of Sleep, 2010). What we do know is that following prolonged periods of sleep deprivation our behavior becomes very bizarre, we suffer from hallucinations, our ability to respond appropriately to the environment is severely impeded, and we might eventually die (Buysse, Strollo, Black, Zee, & Winkelman, 2008). No experiments have been conducted with human subjects that directly substantiate this last bit of speculation, although sleep deprivation of animals sometimes leads to their deaths (Newman, Paletz, Obermeyer, & Benca, 2009).
There are a number of theoretical explanations for sleep. One theory maintains that it is necessary to repair physiological damage and maintain the body and mind in good working order. Evolutionary theory speculates that sleep is an evolved mechanism whose usefulness lies in the fact that hidden sleeping animals are less likely to be preyed upon, particularly if their sleep cycles correspond with predation cycles. It also appears reason- able to suppose that sleep might have evolved as a system for conserving energy. Some
Sleep researchers have identified dif- ferent stages of sleep based largely on eye movements and EEG recordings of brain activity.
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CHAPTER 2Section 2.6 Sleep
researchers suggest that some stages of sleep, especially REM sleep, are important for consolidating memories and perhaps for resting important neural systems.
None of these explanations is necessarily exclusive; that is, sleep might result from a com- bination of factors. But, as Siegel (2003) notes, we still don’t know exactly what is repaired or improved during sleep. And the fact is that none of these explanations has been clearly substantiated. There is no physiological evidence that sleep involves unconsciousness due to oxygen deprivation; the theory of cell damage remains unsupported; and no toxins or other harmful substances have been discovered to accumulate in the body’s cells that must be destroyed through sleep. Nor is there any significant change in the body’s con- sumption of energy during sleep, so that the commonly held belief that the body needs to sleep in order to conserve and restore its energy levels does not appear to be substanti- ated either. Despite marked declines in physiological functioning during sleep, the level of energy consumption increases dramatically during the first hour of sleep, although it falls off rapidly after that.
So the question of why we sleep remains unanswered. It is a missing piece of the puzzle, although we have a pretty clear notion of what the implications of not sleeping are. Nor do we know why we dream: another missing piece.
REM
NREM
Hours of sleep
0 1 2 3 4 5 6 7 8
Normal sleep cycle
NREM sleep cycle interrupted, resulting in less REM sleep
Increased REM states and shorter NREM periods after REM deprivation
Awakened Awakened
REM
NREM
REM
NREM
Figure 2.12
Cycles of REM/non-REM sleep. During a normal sleep cycle, REM sleep occurs fairly regularly at about 90-minute intervals and lasts for 25 minutes or more. If we are awakened from non- REM sleep, REM sleep will not begin for 30 minutes or more after the onset of sleep. If we are awakened during REM sleep (as in a dream-recording experiment), the result is shorter non- REM periods between REM states during the subsequent night.
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CHAPTER 2Section 2.6 Sleep
Dreams
Contrary to some beliefs, everybody dreams: But not everyone remembers dreams with equal clarity. In fact, most people remember only a small portion of what they dream, with women remembering their dreams more often than men (Schredl, 2010). Nor, as is popu- larly believed, is a dream a condensed version of real-time events. Indications are that the amount of time that might have elapsed had dream events been real is very similar to the amount of time during which the dream occurred. Evidence that this is so is derived from tracings of eye movements, from verbalizations, or from movements corresponding to an event in a dream. Interestingly, in many cases, eye movements during dreams appear to actually scan dream objects. It is as though dreamers were actually looking at the dream scene or at the object for which they’re reaching (Leclair-Visonneau, Oudiette, Gaymard, Leu-Semenescu, & Arnulf, 2010).
Why We Dream Psychologists are not certain why we dream. Nor can we easily investigate the effects of not dreaming because doing so requires the interruption of sleep and any observed effect could as well be due to sleep deprivation as to dream deprivation. Still, we have a number of dream theories.
1. Dreams as symbols for disguised impulses. Perhaps the best-known dream theory is that proposed by Sigmund Freud—sadly, a theory that is generally unsupported by any scientific research. Freud believed that dreams represent disguised mani- festations of unconscious impulses. He thought that most of these impulses are linked to sexual desires, aggression, or other socially taboo inclinations. Hence they’re disguised, even in dreams, as a form of self-protection or, more precisely, as a form of sleep protection. Were they not disguised, we would continually awaken horrified at our vile and base cravings. If the father we want to mur- der appears in a dream as a spider, we can step on that creature with no fear of self-reprisal. Only Freud and other gifted psychoanalysts would be expected to recognize the spider.
2. The threat-simulation theory of dreams. Another dream theory suggests that our dreams provide us with an opportunity to practice responding to threats. This might be why, as Revonsuo (2000) suggests, so many of our dreams and night- mares have to do with chasing or being chased. Revonsuo’s Threat Simulation Theory argues that even though our legs and arms might not be moving while we dream, we might still be practicing a variety of “fight and flight” responses. In support of this theory, there is evidence that when we dream our brains often fire in ways highly similar to the way they might fire if we were awake and actually threatened.
3. Dreams as cognitive tools. There is also the possibility that dreaming may have a ben- eficial effect on cognitive functioning and attention (Cartwright, 2010). This is sug- gested by studies of partial and temporary dream deprivation, accomplished by waking individuals at the onset of REM periods. In the absence of dreams, explains Cartwright, the individual finds it difficult to attend to reality upon awakening.
Additional evidence that dreams might provide a cognitive benefit is found in the observation that when rats are placed in mazes during the day, their patterns of brain activity that night closely parallel their brain activity while they were in
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CHAPTER 2Section 2.7 Hypnosis
the maze (Ego-Stengel & Wilson, 2010). These authors suggest that dreams pro- vide us with an opportunity to sort our memories into those worth remembering and those we can afford to forget.
4. Dreams as therapy. Another current dream theory, somewhat reminiscent of Freud’s, suggests that dreams are a form of therapy. Hartmann (2007) notes that dreams are often laden with emotion. As such, they provide an opportunity to confront difficult and surprising emo- tions and perhaps learn how to deal with them. Dreams allow us to think through our emotions.
In this connection, Cartwright (2010) notes that the various dreams collected from a single indi- vidual on the same night typically present such a coherent pattern that it is impossible to believe that dreams represent random happenings. She argues that dreams may well have a therapeutic purpose, since they often appear to be directed toward the resolution of conflict-laden situations.
And, of course, there are those who believe that dreams serve none of these functions—that they are simply the result of random brain activity.
2.7 Hypnosis
Sleep—and the dreams that might then come—are one state of consciousness; being awake is the other. Does hypnosis represent a third, altered type of consciousness?
Perhaps, although the final verdict is not yet in. We are not quite certain about hypnosis—not even certain whether or not we should investigate it: There has long been a faint odor of mysticism and of magic about the subject. We often fear and distrust the mysterious. Many misconceptions surround hyp-
nosis, partly owing to years of dem- onstrations of bizarre activity onstage. Only within the past few decades has it become a serious focus of psycho- logical research.
Relatively few dreams are nightmares. These tend to occur near the end of non-REM sleep rather than during REM sleep (which is when most other dreams occur).
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CHAPTER 2Section 2.7 Hypnosis
Some Facts
Contrary to some popular misconceptions, hypnosis does not involve some powerful per- sonality putting subjects into a state where, zombie-like, they have to obey. As defined by the American Psychological Association, hypnosis is a procedure where subjects are given suggestions for “imaginative experiences” and where “one person (the subject) is guided by another (the hypnotist) to respond to suggestions for changes in subjective experience, alterations in perception, sensation, emotion, thought or behavior” (The Official Division 30 Definition and Description of Hypnosis, 2010).
Basically, what happens in hypnosis is this: The hypnotist uses some form of what is termed hypnotic induction to heighten the suggestibility of the subject (Gafner, 2010). A common hypnotic induction technique, the eye-fixation method, uses an object to focus the subject’s attention while the hypnotist speaks. Pocket watches were used extensively in 19th-century France and Germany and are often shown in graphic portrayals of hyp- notists plying their trades. Of course, it is not an object that induces hypnosis, but the hypnotist’s words. A very common induction technique does not ask subjects to fix their gaze on an object; it simply uses verbal directions to increase the subject’s relaxation and suggestibility.
A rather surprising discovery is that, in terms of physiological functioning, a hypnotic state is much closer to a waking state than to a sleep state. EEG waves are typically alpha, and respiration and heart rate may range from deep relaxation to strenuous physical activity. The single most striking feature of a hypnotic state is the willingness of subjects to do what is asked and the matter-of-factness that accompanies even the most bizarre behaviors requested of them.
Is Hypnosis a Different State of Consciousness?
Whether hypnosis is a different mental state or whether it simply involves imaginative role-playing remains uncertain and controversial (Revonsuo, Kallio, & Sikka, 2009). Much of the research that has looked at this question has compared the performance of hypno- tized subjects with that of others pretending to be hypnotized. Those who believe that hypnosis represents a different state of consciousness try to find differences between the psychological processes of hypnotized and nonhypnotized persons; those who think hyp- nosis involves imaginative role-playing look for similarities.
Among other things, this research has sometimes found that simulators are often capable of many of the same impressive feats and deceptions as are hypnotized subjects, including total-body catalepsy (rigidity), apparent amnesia, age regression, hallucinations, and the ability to tolerate pain (anesthesia) (Orne, 2009). These findings would seem to support the notion that hypnosis does not represent an altered state of consciousness.
However, there are studies indicating that brain activity changes during hypnosis (Naish, 2010); simulators are not ordinarily able to alter their brain activity deliberately to please an investigator. For example, when hypnotized subjects are instructed to imagine that
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CHAPTER 2Section 2.8 Drugs and Consciousness
black-and-white objects are brilliantly colored, activity in the part of the brain associated with color vision increases; this is not the case for nonhypnotized participants asked to imagine the same thing (Oakley & Halligan, 2010).
Applications of Hypnosis
There is evidence that the use of hypnosis can be effective for a variety of medical proce- dures, including childbirth and even surgery. It has also been used successfully in den- tistry (Brown, 2009).
A variety of psychotherapies also make use of hypnosis (Barber & Westland, 2011). For example, Almas and Landmark (2010) reviewed a large number of studies where the use of hypnosis was effective in treating sexual problems.
Hypnosis has also been used in courtrooms in an attempt to help witnesses, and some- times victims, recall details of a crime. However, because it is difficult to establish the veracity of what hypnotized individuals appear to remember, the use of hypnosis in court remains highly controversial (Lynn, Boycheva, Deming, Lilienfeld, & Hallquist, 2009).
The results of research that has attempted to determine whether hypnosis can be benefi- cial in the teaching-learning process remain somewhat uncertain. Some studies claim to have demonstrated that learning, motivation, and retention can sometimes be improved as a result of posthypnotic suggestion (Vernon, 2009). But other studies have failed to find differences between experimental groups and control groups, particularly when control groups are highly motivated. The most valid conclusion to be derived from a large num- ber of related studies appears to be that hypnosis can be very effective in increasing moti- vation, but that it does not increase intelligence or memory. There is virtually no evidence that it has any harmful effects.
2.8 Drugs and Consciousness
Consciousness refers to our personal conceptions of the realities that surround us and of who we are. Sleeping and waking are natural states of consciousness, regularly and predictably manifested in humans; hypnosis may represent an altered state of conscious- ness, the alteration seldom being very dramatic or violent. Various recreational and addic- tive drugs, which we look at in Chapter 9, can provide yet another way of shaping reality. Or is it fantasy that drugs shape?
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CHAPTER 2Main Points
Main Points
1. Evolution: The species Homo sapiens has evolved with certain physical limitations but with a remarkable brain and nervous system.
2. The Neuron: The basic unit of the nervous system is the neuron, of which we have close to 90 billion in the brain alone. Neurons, through chemical and electri- cal activity, compose our communication systems, the intricate arrangements of which define our very essence.
3. Organization of the Nervous System: The brain and spinal cord make up the central nervous system; the peripheral system includes the somatic system (con- cerned with bodily sensations) and the autonomic system (the sympathetic and parasympathetic systems concerned with unconscious physiological responses). Endocrine glands, such as the pituitary, the adrenal glands, and the gonads, pro- duce hormones involved in growth, maturation, emotion, and behavior.
4. The Brain: The brain coordinates activity in these diverse systems. Its major divi- sions are the hindbrain (the medulla, pons, and cerebellum, involved in balance and locomotion, respiration, sleep, and arousal), the midbrain (the reticular formation involved in arousal and motivation), and the forebrain (the hypothalamus, con- cerned with temperature regulation and circadian rhythms; the thalamus, a relay center; the limbic system, implicated in emotions; and the cerebrum, divided into the four cerebral lobes, which include the visual and auditory cortices and the asso- ciation areas of the brain). The brain stem includes structures of both the hindbrain and the midbrain.
5. Biology and Behavior: Biology prepares the human animal to learn and do cer- tain things easily (learning languages; learning taste aversions) but makes other behaviors difficult (restraining our cravings for fat and sugar). Our consciousness seems to reside in patterns of activity in our brains.
6. Sleep: Sleep, of which there are two states, REM sleep (during which we do most of our dreaming) and non-REM sleep, is not a completely unconscious state. Stages of sleep are distinguishable by the nature of accompanying brain waves, ranging from small fast beta waves when awake, through alpha, theta, and delta waves (progressively slower and deeper). We don’t know clearly why we sleep or why we dream, but we do know that deprivation has negative consequences.
7. Hypnosis: Hypnosis is a procedure where subjects are given suggestions for “imaginative experiences” that lead to “alterations in perception, sensation, emo- tion, thought, or behavior.” Its hallmark is the desire of participants to obey the hypnotist’s instructions. It is not clear whether it represents a different state of consciousness, but it has important implications in medicine and psychotherapy.
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CHAPTER 2Main Points
Study Terms
acetylcholine
action potential
adrenal glands
adrenaline
agonists
alpha waves
amygdala
antagonists
association areas of the brain
attention-deficit hyperactivity disorder (ADHD)
autonomic nervous system
axons
beta waves
biological constraint
brain
brain stem
central nervous system
cerebellum
cerebral cortex
cerebrum
circadian rhythm
consciousness
creationism
delta waves
dendrites
dopamine
echolocation
effectors
electroencephalogram (EEG)
endocrine system
evolution
evolutionary psychology
frontal lobes
functional magnetic resonance imaging (MRI)
glial cells
gonads
hippocampus
holistic education
hormones
hypnosis
hypothalamus
instinctive drift
limbic system
magnetoencephalography (MEG)
medulla
melatonin
mind
molecular genetics
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CHAPTER 2Main Points
myelin sheath
nerves
nervous system
neurogenesis
neurons
neurotransmitters
norepinephrine
occipital lobes
paradoxical sleep
parasympathetic nervous system
parietal lobes
Parkinson’s disease
peripheral nervous system
pituitary gland
pons
positron emission tomography (PET)
rapid-eye-movement sleep (REM sleep)
receptors
refractory period
reticular formation
reuptake
Sapir-Whorf hypothesis
serotonin
somatic system
spinal cord
suggestibility
sympathetic nervous system
synapse
synaptic knobs
temporal lobes
thalamus
theta waves
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3
Sensation and Perception
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • How are sensation and perception different? • How does the eye function? • What causes visual illusions? • How does the auditory system work? • What are the body senses? • Which are the two chemical senses? • What five distinct tastes do humans perceive?
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CHAPTER 3Sensation and Perception
Seeing , hearing and feeling are miracles, and each part and
tag of me is a miracle. —Walt Whitman, Leaves of Grass
Chapter Outline
3.1 Sensation and Perception Functions of the Senses
3.2 Vision Structure of the Eye Eye and Brain Light Waves and Vision Color Vision Vision in Low Light Characteristics of Visual Perception Illusions
3.3 Attention and Perception
3.4 Hearing Three Functions of the Auditory System Perception of Sound Waves The Auditory Apparatus
3.5 The Body Senses The Vestibular Sense The Skin Senses The Kinesthetic Senses
3.6 The Chemical Senses Olfaction Taste
3.7 Adding Pieces of the Puzzle
It does all seem a miracle as a wild orchid, flaming yellow, catches your eye.
Standing in front of the orchid, imagine for a moment an atom of gas somewhere on the sun’s surface. This atom has been baked in heat you can scarcely imagine until, quite suddenly, it is transformed into a different energy state, a photon, a tiny packet that is hurled toward the earth at the amazing speed of 186,300 miles per second. Still, it takes a full 8 minutes before this photon streaks through the earth’s atmosphere, strikes the orchid, and, along with uncounted other photons that have made the same journey, bounces off those dazzling petals and disappears through a tiny black hole.
The hole is the pupil in your eye. The photon slips right through the transparent cover over this hole, through some heavy fluids, and on through a layer of nerve cells—all in microseconds. Chemi- cals in light-sensitive cells at the very back of your eye trap an avalanche of these tiny photons. Now, almost miraculously, the photons disappear as their energy is transformed into nerve signals that, in some astonishing way, mirror the shape and color of the orchid. And as these signals reach your brain, you marvel at how exquisite the flower looks.
Meanwhile, somebody behind you forces a burst of air through cords in his throat. The cords vibrate, he traps the vibrations in his mouth, and, like a wizard, splits and shapes them with teeth and tongue and lips. In so doing, he releases billions of tiny air molecules that form rhythmic waves fanning out in all directions. The waves cause an almost imperceptible sequence of vibrations in your eardrums that exactly reflect the vibrations created by the voice.
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CHAPTER 3Section 3.1 Sensation and Perception
Now a series of tubes and bones and fluids transmits these vibrations through your auditory system. And, in the end, they too are transformed into neural impulses that flash toward your brain. You know at once that this is Hans speaking; the vibrations of his voice are like a label. Not only that, but you know that he is somewhere behind you and to your right. And perhaps even more astonish- ing, you draw from these vibrations a meaning nearly identical to that which Hans intended.
As all this is happening, tiny molecules have risen into the air from the bacon and the coffee on the campfire. A few of these molecules happen to drift up your nose and, bingo, they activate a series of neural impulses that blaze toward your brain, and in that fleeting moment, you can almost see the bacon and the coffee.
As you walk barefoot toward the campfire, tiny cells in the soles of your feet translate the tempera- ture and the pressure of the grass into yet another layer of awareness.
In these many simultaneous events, there are surely pieces of the human puzzle.
3.1 Sensation and Perception
What an incredible amount of activity in a single brain! How fortunate that this brain, hidden as it is in its bony skull, has these portals that allow it to know what is out there. Our senses are our brain’s windows. They are our contacts with the outside world. They include vision, hearing, the chemical senses (taste and smell), and the body senses (the vestibular sense involved in balance, the skin senses involved in sensations of pain, temperature, and touch, and the kinesthetic senses, concerned with sensations of body position and movement); see Figure 3.1.
Strictly speaking, sensation is the immediate response of our senses to sensory stimula- tion; perception is the brain’s interpretation of the signals it receives from its various sensory systems. Light waves striking your eyes when you look at an orchid produce a sensation on your retina. This sensation gives rise to neural impulses that, when they reach your brain, result in your perception of the orchid.
Although these definitions distinguish between perception and sensation, in practice, the two are inseparable. Perception clearly depends on sensation; it is, after all, our interpreta- tion of sensation. But were it not for the meaning we give what we sense, would we even be aware of sensation?
Functions of the Senses
All sensory organs may be considered to have evolved not to induce sensations, but to make it possible for us to perceive: They make up a coordinated set of perceptual sys- tems that provide us with different kinds of information about ourselves and about the world. Although each sensory system is distinct and depends on different sets of circum- stances—vision depends on light and hearing, on sound waves—they function together. Each relays information to the same brain, often giving us information about the same objects or events. For example, my ears might inform me that there is a horse behind me;
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CHAPTER 3Section 3.1 Sensation and Perception
my eyes might tell me the same thing if I turn to look, revealing as well its color; my hands might confirm the nearness of the animal and suggest as well that it is both smooth and warm; and my nose might tell me other things about horses.
Body senses (vestibular
kinesthetic, skin)ki
New shoes
Hearing
Vision
Chemical senses
(olfaction and taste)
Figure 3.1
The human senses. Note that while there are easily identified, specialized receptors for hear- ing, vision, and the chemical senses (smell and taste), the body senses (orientation, touch, and somatosensation) involve receptors that are found throughout the body. Orientation and bal- ance are highly dependent on the inner ear and are sometimes labeled the vestibular sense.
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CHAPTER 3Section 3.2 Vision
3.2 Vision
The visual system allows us to detect our surroundings and to detect changes in those surroundings. It also provides a means of detecting movement—both our own and that of others—and of controlling it.
Structure of the Eye
The marvelous organs that permit visual perception are the eyes—two spherical objects relatively isolated from the bloodstream, covered by a transparent coating called the cor- nea. The cornea and the lens have no blood supply and can therefore be transplanted with little risk of rejection. Nutrients for the cornea and lens are obtained from the aque- ous humor, the fluid between the lens and the cornea, which is changed continually (Figure 3.2).
Each eyeball is controlled by an intricate arrangement of muscles that rotate it in differ- ent directions in all planes. The eyeballs are in continual motion, the motions being rela- tively smooth when a moving object is being followed and jerky when a stationary object is being looked at (called saccadic movements). In the absence of any movement, visual acuity quickly fades. In fact, if eye tremors did not move an image on the retina, it would eventually disappear completely.
blind spotvitreous humorlens
filled with aqueous fluid
optic nervefoveasclera
pupil
iris
cornea
retina
anterior chamber
posterior chamber
Figure 3.2
Parts of the human eye, the marvelous organ that is sensitive to light waves and permits visual perception.
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CHAPTER 3Section 3.2 Vision
Another very important muscle for the eye is the iris, which, in humans, creates a round opening (the pupil) that allows light to enter the eye. Interestingly, humans are among the few animals that have circular pupils, most other animals having almond-shaped, slit, or oval eyes. Note that the pupil is not a structure, but is simply an opening created by the iris muscle. The iris contracts the pupil in bright light and expands it in dim light to con- trol the amount of light that enters the eye. It is the iris that gives our eyes color.
Immediately behind the iris is the lens, which focuses incoming light waves on the retina, the light-sensitive portion of the eye. The human lens focuses by elongating, becoming thinner, or by contracting, becoming thicker. With advancing age, adaptation of the lens becomes more difficult and many people become more farsighted, a condition that can be corrected with the use of artificial lenses (eyeglasses).
light
To optic nerve
retina
bipolar layer receptor layer (rods and cones)
ganglion layer
Figure 3.3
The retina is composed of three layers of cells. Farthest from the light source are the rods and cones. The function of rods is to respond to brightness; the less sensitive cones are involved in color vision and visual acuity. Rods and cones change light energy to neural impulses. The second layer of cells consists of bipolar and horizontal nerve cells that receive neural impulses from the rods and cones. From the bipolar layer, impulses are transmitted to the ganglion cells, and the axons of this last set of cells lead to the optic nerve.
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CHAPTER 3Section 3.2 Vision
The retina is lined with more than 120 million nerve cells capable of translating light waves into neural impulses (Figure 3.3). Retinal cells sensitive to light are labeled rods and cones because of their shape. Rods outnumber cones by about 20 to 1 (115 million compared with 6.5 million). The cones are found throughout the retina but are concentrated in its center (the fovea), which is some distance from where the optic nerve branches out to the visual portions of the brain. Because rods and cones are absent where the optic nerve exits, this area is a blind spot. Figure 3.4 illustrates how you can test for your blind spot.
Rods and cones have different functions in visual perception. Rods respond primarily to brightness, are involved in night vision, and are more sensitive to low light. Cones function mainly in daylight, are involved in color vision, and provide the clearest detail, although they’re considerably less sensitive. Since light coming into the eye from directly in front tends to strike the retina in the area of the fovea (where cones are most concen- trated), greater detail and sharper colors can be seen in daylight by looking directly at an object. But at night, it is often possible to see an object more clearly by looking slightly away from it so that more light waves strike the retina in an area away from the fovea, thereby coming into contact with more rods.
Eye and Brain
The eye itself doesn’t actually register images: these are in the “mind” rather than the eye. What the eye does is respond to light waves that its lens focuses, inverted and miniatur-
Figure 3.4
The blind spot is “blind” because there are no rods or cones in the area where the optic nerve leaves the eye, so no image can be transmitted from the impulses that reach that small section. To find your blind spot, stare at the triangle with your left eye closed and move the book back and forth between 8 and 20 inches away. At the appropriate distance, the circle will disappear. To find the blind spot in your left eye, close the right, stare at the circle, and move the book until the triangle disappears.
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CHAPTER 3Section 3.2 Vision
ized, on the retina, giving rise to neural impulses that the optic nerve then transmits to the visual cortex. Hence both the eye and the brain are involved in vision.
Information from the right half of each eye (left visual field) goes to the right hemisphere; information from the left half of each eye (right visual field) goes to the left hemisphere. The crossover occurs at the optic chiasma (Figure 3.5). From there the optic nerve goes to the thalamus, the brain’s major relay station, with some branching to the reticular forma- tion. The majority of the impulses go from the thalamus to the visual areas of the cortex (in the occipital lobe at the back of the brain); others go to a part of the midbrain where they make connection with nerves that control eye movements. What is perceived, in the end, is not a retinal image, inverted, miniaturized, flat, and in two dimensions like a pho- tograph; it is not even an image in the brain. What we perceive through vision seems to be real and out there, colored, textured, and in three dimensions.
Light Waves and Vision
Eyes are responsive to light, a mysterious entity that exists in little packages called pho- tons. Photons, physicists inform us, have properties of both particles and waves (Walker, Halliday, & Resnick, 2008). Human eyes are sensitive not only to the length (frequency) of waves, but also to their amplitude and their complexity.
thalamus
visual cortex (occipital lobe)
optic chiasma retina
optic nerves
left visual field
right visual field
Figure 3.5
Images from the left visual field are transmitted to the right side of each retina, then on to the right hemisphere. Images from the right visual field are transmitted to the left half of each retina, then on to the left hemisphere. The optic nerve carries impulses from the retina through the optic chiasma, on through the thalamus, and then, usually, on to visual centers of the occipital cortex.
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CHAPTER 3Section 3.2 Vision
Wavelength Because light waves travel at a constant speed (186,300 miles per second), their frequencies are a function of wavelength. Blue light has a wavelength of approximately 1/70,000 inch; red light, of 1/40,000 inch (Gregory, 1997). Some idea of the incredible speed and frequency of light waves is given by the notion that some 70,000 waves corresponding to blue occupy a mere linear inch of space, and that these waves can reach the moon and back in just 3 seconds.
Because of the very high numbers that result, wavelength is seldom expressed as frequency per inch, but is measured instead in nanometers (a nanometer is one-billionth of a meter). In these terms, visible light ranges from just below 400 nanometers (violet) to just above 700 nanometers (red). Electromagnetic waves, of which visible light is an infinitesimally small part, range from gamma rays and X-rays to the various radio bands. The gamma rays have considerably higher frequencies; radio waves have much lower frequencies and con- sequently much greater wavelengths. Wavelength, within the narrow band of electromag- netic activity to which our eyes are sensitive, corresponds to hue (color), ranging through all the colors and different shades of the rainbow from red to violet (Figure 3.6).
Low Frequency
700 nm 390 nm
Ra dio TV
M icr
ow av
e
In fra
re d
Vi sib
le Lig
ht
X- ra
y
Ga m
m a
ra y
High Frequency
Figure 3.6
The electromagnetic spectrum. The human eye can perceive only a very narrow band of waves, from around 390 to 700 nanometers. The rest of the spectrum, from gamma rays to long-wave radio waves and beyond, cannot be seen directly.
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CHAPTER 3Section 3.2 Vision
Amplitude Amplitude of light waves corresponds to intensity and gives rise to the subjective experi- ence of brightness. A given hue has a specific wavelength (or wavelength mixture). Increas- ing the amplitude of light waves doesn’t result in a change in color any more than striking a piano key more or less firmly results in a different note. But in the same way as the note will be louder or softer depending on how hard you bang on it (that determines its ampli- tude), a hue will appear brighter or less bright as a function of wave amplitude (Figure 3.7).
Complexity and Color Purity Most of the light we perceive and the sounds we hear are mixtures of different wave- lengths. The subjective effect of these mixtures is saturation or purity. The less complex (purer) a wavelength is, the more saturated the color seems.
Color Vision
Rods and cones are photo-sensitive cells whose chemical composition allows them to respond to light. The main chemical in rods is rhodopsin; in cones it is one of three forms of iodopsin. The effect of light of the right intensity and characteristics is to break down these chemicals. This process initiates activity in some of the neural cells that line the retina.
Color corresponds to wavelength, as is evident in the color spectrum shown in Figure 3.6. This fact can be illustrated by means of a prism that separates white light—a mixture of wavelengths characteristic of most light sources—into separate wavelengths. If nature
Figure 3.7
Light waves can vary in amplitude without causing a change in hue (color). Instead, greater amplitude, as shown toward the right of the wave, results in the perception of greater intensity or brightness; less amplitude means less brightness.
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CHAPTER 3Section 3.2 Vision
were really simple, it might then follow that different receptors in the eye would be sensi- tive to each of the different wavelengths that correspond to the colors of a rainbow. Acti- vation of one or more of these receptors would account for color vision.
Trichromatic Theory: Young-Helmholtz That doesn’t seem to be the way the eye works. It turns out that in order to see millions of different hues, we don’t need millions of different types of cones (Billock & Tsou, 2010). In fact, one theory suggests that we need only three. This theory is based on the observation
Figure 3.8
Create your own afterimage. Stare at the center of the upper figure for 15 to 30 seconds, then shift your gaze to the center of the blank square below. What you see is a negative afterimage, so called because its colors are complementary to those of the original image.
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CHAPTER 3Section 3.2 Vision
that mixing only three colors can produce all other colors. The theory was proposed by Young and Helmholtz, and is now known as the Young-Helmholtz trichromatic theory.
The theory says that our cones are each sensitive to a single color: red, green, or blue. Fur- thermore, each of these cones is linked to different “color-producing” areas of the brain. Mixtures of different wavelengths, which account for all other colors, give rise to differ- ential activity in two or more of the three cone systems, and this combined activity then leads to the subjective experience of a color other than red, blue, or green. Perception of a yellow orchid, for example, would result from the stimulation of red and green color systems. This would occur in response to wavelengths at around 580 nanometers.
Opponent Process Theory: Hering Trichromatic theory doesn’t explain all aspects of color vision. For example, if you look at Figure 3.8 long enough, you will experience what is labeled an afterimage—a visual image that persists even when you’re no longer looking at the stimulus. The fact that this image appears in opposite colors suggests that cones might react to complementary colors, thus functioning as dual color systems. Red and green are complementary, as are blue and yellow. We cannot see reddish greens or bluish yellows. This observation leads to the speculation that there is a red-green system and a blue-yellow system. It also leads to the speculation that there is a third system that responds to black and white to account for the perception of brightness.
The fact that color blindness is most often of the red-green variety and sometimes of the blue-yellow variety lends additional support to what is called Hering’s opponent pro- cess theory of color vision (Figure 3.9). The theory suggests that the cones themselves are responsive to different wavelengths. Cells activated by shorter wavelengths are inhibited by longer wavelengths. Mixtures of wavelengths activate different cells, giving rise to dif- ferent perceptual experiences of color. The red-green system is an opponent system. When the red member of the pair is active, the green member will be inactive. Interaction among red-green and blue-yellow systems, together with the light-dark (black-white) system, will produce all other colors.
While trichromatic theory is correct that we do have three different cone systems, opponent- process theory is also supported by experimental evidence and provides a good explana- tion for color blindness and afterimages (Shevell & Krantz, 2010). Most researchers now accept that trichromatic theory best explains how cones work and that opponent-process theory better explains processing beyond the receptors, at the level of the bipolar cells.
Vision in Low Light
Our eyes don’t just translate photons into neural impulses. Even at the level of the eye, there is a type of learning evident in the fact that eyes can become more or less sensitive under different circumstances. For example, when we go from a sunny beach into a dimly lit hut, we initially see only vaguely. But very shortly, our eyes become more sensitive to the gloom—a process called adaptation.
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Research indicates that cones are considerably less sensitive to conditions of low light than are rods. They adapt about as much as they will within 7 or 8 minutes. Rods, however, are more sensitive to light and continue adapting for as long as half an hour or more. Since cones are responsible for color vision and rods for brightness (light-dark), this explains in part why vision is less colorful in dim light. Both the peacock’s preening and the lady’s lipstick will be less effective by moonlight.
Figure 3.9
A common test for color blindness, a phenomenon that is not always all-or-none. If you are not color blind, you should have little difficulty seeing the number 5.
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Experiments with frogs’ and cats’ eyes suggest that adaptation to darkness is in part a function of the regeneration of visual pigment in the retina (rhodopsin), which is bleached during exposure to white light. This bleaching process appears to be minimal with red light, however; hence the use of red light bulbs in photo-developing labs and in other situations where workers alternate between darkness and light. Once the eyes are dark- adapted, they will continue to be following exposure to red light.
Not only is sensitivity to detail and color dramatically reduced in conditions of near dark- ness, but the amount of time required for the brain to perceive a visual scene is signifi- cantly greater. You can illustrate this dramatically by suspending a weight on a length of string and making it swing in a straight arc in front of a subject who has one eye adapted to low light and the other to ordinary light (this is accomplished by placing a dark sun- glass lens over one eye). The result is that messages from the dark-adapted eye reach the brain slightly later than those from the uncovered eye, and the pendulum seems to describe an ellipse although its path is straight—a phenomenon labeled the Pulfrich pen- dulum effect (Benjamin, 2008).
Because of perceptual delay in dim light, reaction times are slower and activities such as driving a car or piloting an airplane are more dangerous. It is also more difficult to catch a baseball, to avoid being hit by a tennis ball, or to net a butterfly or a bat.
Characteristics of Visual Perception
Not only do we believe what we see, but we tend to believe that we see all that there is to see. In fact, however, sometimes we see much less, and sometimes much more—as in the case of mirages, for example.
The Visual Constancies Our minds can be deceived in a number of ways by our eyes, but they can also correct
in advance for errors that would surely result if we always relied solely on information in light waves. The fact is that the brain continually makes adjustments based on our experiences and expec- tations. As a result, we don’t always see things in ways that correspond exactly to relevant light waves. The visual constancies are a case in point.
We know that most oranges are orange, most windows are square or rectangular, and most elephants are large. We almost always perceive them as such. Our perceptions illustrate color constancy, shape constancy, and size constancy.
Color Constancy For example, we take for granted that colors don’t change with changing light conditions or with changing backgrounds. Yet that they do is clear, but since we generally
Mirages deceive the brain but not the eye. Although the buildings in the background are a mirage, the light waves that strike the retina—or that enter the camera—have real physi- cal properties that correspond to the buildings.
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CHAPTER 3Section 3.2 Vision
know what the colors of familiar objects are, we tend to perceive them that way, somehow compensating for brighter or darker conditions, or for the effects of contrast or the lack thereof. When Granzier, Brenner, and Smeets (2009) had subjects identify one of six sheets of paper of extremely similar colors in indoor and outdoor conditions that differed signifi- cantly in lighting, they were successful far more often than would be expected by chance.
Size Constancy Do you think the face that looks at you from your mirror is about the same size as your own face? It isn’t. In fact, it’s smaller because your reflection is always halfway between you and yourself. Light waves reflected from an object back to that same object must travel the distance between the object and the reflector twice, in a sense leav- ing the reflection at the halfway point. If you fog up your bathroom mirror and circle your reflection with a finger, you may be amazed at how small the circle you have made actu- ally is. Yet you perceive your reflection as being the same size as you imagine yourself to be.
The size of a retinal image is a function of the distance between the perceiver and the perceived. The farther you are from an object, the smaller the image projected on the retina—in the same way as photographs of an object taken with the same lens but at dif- ferent distances will depict objects of measurably different sizes. Subjectively, however, the perceived size of familiar objects doesn’t change with distance. You don’t assume that
Figure 3.10
Size constancy. At the top, trees of identical length project progressively smaller images on the retina, yet they are perceived as equal in height. At the bottom, trees of different heights proj- ect identical retinal images, yet are perceived as being different in height.
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a car grows as it approaches, even though the size of the retinal image increases. Quite the opposite: As the retinal image increases in size, you realize the car is approaching.
But if we did not know how big the car was to begin with, we might well misjudge its size at a distance. Knowledge that we have about the constancy of size in the physical world provides dimension for our visual perceptions in the same way as knowledge about the colors of familiar objects serves to color them. Figure 3.10 illustrates how distance can serve as an index of size. The retinal images cast by the three palm trees at different dis- tances will be quite different, but the trees will be perceived as being the same size.
In the absence of cues concerning distance, however, and when dealing with unfamiliar objects, perceptual judgment can be unreliable. The Ames room (Figure 3.11) provides a well-known example of size distortion as a function of environmental cues. When observed from a single peephole, the room appears square, although it is actually trapezoidal and has a sloped ceiling. Because distance between the subjects’ heads and the ceiling is a cue for judging their sizes, subjects of the same height appear dramatically different.
It seems clear that perception of size is less related to size of retinal images than to other contextual cues, including distance and what we know about the normal size of familiar
Real place and size of “smallest” girl
“Largest” girl
Apparent place and size of “smallest” girl
a b
apparent walls
real walls
peephole for one eye
Figure 3.11
The Ames room creates an illusion by distorting the context and having you look inside with only one eye. Photograph a, which is how it appears to the viewer, shows a short girl in one corner and a much taller girl in the other. But b reveals that the room is trapezoidal rather than square, and the ceiling is sloped upward from right to left. In fact, the girls are of equal height. (Photo courtesy Mateusz Stachowski.)
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CHAPTER 3Section 3.2 Vision
objects. It appears that estimation of size is excellent for virtually as far as we can see an object, provided we are not misled in our perceptions of distance. Figure 3.12 illustrates how perceptions of size can be distorted through perspective.
Shape Constancy Under most circumstances, our use of contextual cues, together with previous knowledge of the sizes, shapes, and colors of objects, leads to relatively accurate perception. This is no less true with respect to shape than with respect to size and color. If you hold a cup at an angle in front of you, the retinal image of the cup’s mouth is oval rather than circular. Yet you would not judge it to be oval (see Figure 3.13). Similarly, most doors are rectangular. In fact, however, a door appears rectangular only when faced directly. As it opens, it projects retinal images that change considerably in shape, but we don’t see these changes; we continue to “see” the door as rectangular.
Perception of Depth and Distance As Pizlo, Sawada, Li, Kropatsch, and Steinman (2010) point out, what we perceive in our minds is a three-dimensional shape in spite of the fact that the projections on our retinas are flat, two-dimensional images. Our perceptions have depth, as well as distance from the perceiver and distance relative to each other.
Binocular Cues Two of the ways by which we judge distance and depth result directly from the fact that we have binocular vision. Our two eyes look at the same visual field, unlike the eyes of rabbits and chickens, which look at two different worlds. Eyes that look in two different directions provide a much wider field of view—a useful adaptation for birds and animals that must constantly be on the lookout for predators. On the other
a b c
Figure 3.12
Perspective as a cue to size. Because perspective suggests distance, the telephone poles in a all appear to be the same size—which they probably are. But in b, perspective deceives us: The boxes seem to be identical but the nearest is actually larger. In c, the farthest box appears larger although all three are the same size. In b and c, lines across the side wall provide false cues.
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CHAPTER 3Section 3.2 Vision
hand, eyes that look at the same, narrower visual field provide much better depth percep- tion, enabling the predator to judge distance and calculate how to intercept dinner.
We have the eyes of a predator.
One binocular cue for depth and distance results from convergence. When we look at a single object close up, our eyes point slightly inward (converge) so that both are directed toward the object. The angle of convergence in normal vision serves as a range finder. The greater the convergence, the closer the object. When people are made to wear prisms that converge the eyes dramatically, they judge objects as being close. Conversely, they see objects as being farther when the eyes are less converged.
A second cue to depth and distance comes from the fact that each eye’s retinal image for the same object is slightly different because the eyes are approximately 2.25 inches apart. Combining the two different images presented by this stereoscopic vision yields an impres- sion of depth. When subjects are prevented from using binocular cues, their judgments of depth and distance deteriorate significantly (Keefe & Watt, 2009).
Figure 3.13
Shape constancy. The mouths of all the cups are perceived as being round no matter what their position is relative to the viewer.
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Monocular Cues Other cues to depth and distance don’t depend on our having two eyes: hence the term monocular (Figure 3.14). Size is one such cue. When a tree is seen as being very small, we know that it is probably very far away. If we did not know how large an ordinary tree is, our judgments of distance might be inaccurate. Experiments with oversized objects in surroundings that provide no contextual cues as to their actual sizes typically lead the perceiver to assume that the object is closer than it actually is.
Interposition provides a second monocular index of distance. Objects are typically seen as being in front of or behind other objects, with the partly hidden objects always being perceived as being farther than objects that are not hidden.
Perspective, our position in relation to what we perceive, is a third index of distance. Lines appear to converge with increasing distance. This phenomenon is referred to as
A.
B.
C.
D.
E.
A.
B.
C.
D.
E.
Figure 3.14
Besides the binocular cues provided by convergence and stereoscopic vision, there are also monocular cues to depth and distance: (a) size, (b) interposition, (c) perspective, (d) clarity, and (e) shadows.
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linear perspective. A second type of perspective is labeled aerial. It refers to the fact that objects seen at greater distances appear hazy and less brilliant than those seen close up. Similarly, details of texture (clarity) tend to disappear with increasing distance, colors become less bright, and shadows become vague.
Perception of Movement Not only do we perceive objects in depth, complete with judgments of size, distance, and color, but we perceive movement as well. One of the simpler explanations for this fact is that as an object moves it creates different images on the retina. But perception of move- ment is not so simple: If you turn your head slowly with your eyes open, you will cre- ate a succession of distinct retinal images, but you will not perceive any motion of those images. What you will perceive is that your head has moved, and your brain has some- how coordinated the changing visual scene with your own movement. Further, when an unchanging object moves across the visual field and is followed with the eyes, the retinal image does not change, but we see motion.
It might seem clear that changes in an object’s position relative to its background account for our perception of movement. However, we still perceive motion when there is no background whatsoever. If someone moves a tiny light in a dark room, it will be per- ceived as moving even when there is no visible background. The explanation appears to be that the brain can interpret eye movements as indicating movement, despite the fact that the world doesn’t move when you simply move your eyes. Interestingly, however, if the eye is moved by some external force, the visual field does move dramatically. If you close one eye and move the other eyeball by applying your finger on its corner, you can make a room spin.
So it seems, then, that movement is detected through the interplay of what Gregory (1997) describes as the image-retina system and the eye-head system. The image-retina system responds to changes in the visual field that change the retinal image; the eye-head system responds to movements of the head and eyes. And, of course, the brain has to put all this information together, an activity that likely involves a number of specialized neurons in the human visual cortex (Tailby, Majaj, & Movshon, 2010).
Illusions
Visual perception is subject to various forms of misperceptions and illusions. Note, how- ever, that these misperceptions are due less to weaknesses of the sensory aspects of the system than to inappropriate judgments. Often these judgments are based on what we have learned to expect when we see things.
Illusions of movement can be created several ways. Among the most familiar are movies that are, in reality, a succession of static pictures. These pictures are presented sufficiently rapidly that they are perceived as smooth, continuous movement. The type of illusory movement created by a motion picture is termed the phi phenomenon.
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CHAPTER 3Section 3.2 Vision
There are a large number of common geomet- ric illusions, most of which appear to result from expectations that we have about perspective, dis- tance, shape, and size. Misperception of the Ames room (Figure 3.11) is a case in point. Illusions such as the top hat illusion, the Muller-Lyer illusion, and the Ponzo (the fan) illusion can all be explained in terms of our tendency to perceive in depth and more than two dimensions. Thus, the top part of the hat (Figure 3.15a) looks longer than its width because it suggests perspective—distance. Simi- larly, the arrows that form the Muller-Lyer illusion (Figure 3.15b) suggest expansion or compression— distance or its opposite. The Ponzo illusion (Figure 3.15c) is clearly affected by perspective and may be interpreted in terms of our tendency not to per- ceive the background as being flat.
a b
d e
c
Figure 3.15
Visual illusions. The top hat illusion (a) looks as though the hat is taller than the brim is wide, but both dimensions are equal. The Müller-Lyer illusion (b) contains parallel lines of equal length. In the Ponzo illusion (c), the heavy lines are of equal length. If you stare at the Necker cube (d) it eventually reverses itself. In (e), the vertical lines are parallel.
There is no widely accepted explana- tion for the moon illusion—the fact that the moon appears considerably larger at the horizon than it does when it has risen higher.
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CHAPTER 3Section 3.3 Attention and Perception
Another simple illusion that is so common that we tend not to consider it an illusion involves the uncanny way in which the subjects of photographs look directly into your eyes no mat- ter where you stand. You cannot hide. You can sneak up very quietly in the dark, suddenly turn on the light, and they will be staring directly at you. Figure 3.16 illustrates this illusion. When the subject has looked directly into the camera the illusion persists; if the subject’s vision is directed to the side, there is no comparable illusion.
3.3 Attention and Perception
If you now take a moment from your important studies with the deliberate intention of becoming aware of everything that it is possible for you to be aware of at this very moment, you might be completely overwhelmed. Not only is there a stunningly large array of visual stimuli available, but there are sounds, tastes, smells, and tactile sensations of which you were not aware a minute ago if you were paying attention to your reading. Our awareness is limited by our attention.
Figure 3.16
A missing piece of the puzzle in this visual illusion. Why does this person continue to look at you no matter how far over to the side you move? The illusion works with photographs and paintings, but not with three-dimensional art such as sculptures.
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CHAPTER 3Section 3.3 Attention and Perception
Still, there is convincing evidence that the many sensations of which we are not aware nevertheless have an effect on our sensory systems. This characteristic is labeled the cocktail party phenomenon because it is easily illustrated in crowded rooms where many conversations are going on at once. In such situations, it is relatively easy to carry on a conversation without being aware of other simultaneous conversations. But if one of these other conversations turns to a topic of vital interest to you—you hear your name, for example—your attention might immediately switch. Cherry (1953) investi- gated the cocktail party phenomenon by feeding two different messages simultaneously to a single individual using stereophonic headphones. Participants were instructed to pay attention to a single message (left or right ear). To ensure that this was being done, they were also instructed to repeat everything they heard in that ear, a process called shadowing (Figure 3.17).
Using this approach, investigators discovered that subjects don’t remember anything about the message in the unattended ear. For example, the message in that ear can switch from one language to another without the subject’s being aware of it; the same word can be repeated dozens of times and the subject will later deny having heard it (Clump, 2006; Moray, 1959). Astonishingly, however, a single presentation of the subject’s name will almost always alter attention.
“deaf” ear
Subject’s name mentioned
“listening” ear
A tt
en ti
o n
le ve
l
Figure 3.17
How much do we hear of things to which we aren’t attending? In the cocktail party demonstra- tion, participants hear two simultaneous messages, but are instructed to attend to only one. Even when a word is repeated dozens of times in the “deaf ear,” they’re unaware of it. But when the participant’s name is mentioned a single time, attention quickly shifts to the “deaf” ear.
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CHAPTER 3Section 3.4 Hearing
It seems clear that sensory events have some momentary effect even when they’re not being attended to (Brungart & Simpson, 2007). But if they are to have more than a momentary effect, attention is required. Attention precedes perception: It is a state of readiness, of height- ened responsiveness. If you are at this moment attentive to what you’re reading, you’re more likely to perceive it, to understand it, perhaps even to remember it. But if you’re attending mainly to your ongoing daydream, you might be reading these words almost unconsciously.
A number of factors appear to be closely related to attention, most of them having to do with interest or motivation (Chapter 6). Experimentation and observation reveal that stimu- lation characterized by novelty, change, intensity, and complexity is more likely to command attention. Similarly, our interests and preoccupations draw our attention—as is evident in the cocktail party demonstrations where the subject attends immediately to her name but fails to notice a switch to a foreign language.
3.4 Hearing
Clearly, as the cocktail party demonstrations show, we don’t hear with our ears alone: We need to attend so that our brains can perceive what our ears sense.
Three Functions of the Auditory System
The function of the ear is not simply to permit us to hear—that is, to sense vibrations: It has other important functions. First, it allows us to detect the direction, distance, and movements of a sound. It is largely because we have two ears rather than just one that we are able to use our auditory systems as direction finders. Sound waves, the physical energy to which our ears are sensitive, strike our ears at slightly different times unless we are facing directly toward or away from the sound source. Interestingly, however, we are able to orient toward sound primarily in one plane, that being horizontal. Sounds that come from above or below cannot be located nearly as rapidly or as easily, which is why it usually takes a few moments to locate a high-flying plane. The owl, unlike us, has its auditory canals at different angles, enabling it to locate sound sources in more than one plane, which is useful for pinpointing the rustling of mice in the grass below.
Second, the auditory system allows us to distinguish different sounds. We have no dif- ficulty differentiating between thousands of different sounds: bird calls and all manner of wildlife; the countless mechanical sounds of our cities with their automobiles, trucks, buses, bells, chimes, rings, growls, grunts, whooshes, and wheezes. We can identify fall- ing rain, flowing water, showers, drips, lakes, and oceans. And perhaps most important, our marvelous auditory systems enable us to recognize hundreds of different voices.
Finally, it is largely because of our auditory system that we can communicate. And although the auditory system has sometimes received less attention than the visual system, hearing does have some advantages over sight, not the least of which is that it can take place in total darkness. Sound waves are dependent upon a molecular medium, air being the medium of choice, although water and other solids also conduct sound waves. Vision, however, is dependent upon light; without special instruments, it cannot occur in the dark.
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CHAPTER 3Section 3.4 Hearing
Perception of Sound Waves
The phrase sound waves is something of a misnomer. A wave is not a sound any more than a wavelength is a color. The sound is the subjective effect of an event that causes a vibration. Vibrations, described as back-and-forth movements, are caused by mechanical disturbances or dislocations: the movements of vocal cords, the rupturing or breaking of solids; the movements of liquids. The vibrations themselves move through a medium such as air in the form of waves resulting from the alternate compression and rarefaction of air molecules (Figure 3.18).
Waves can be described in terms of the number of waves that are set up in a given unit of time, the amplitude of these waves, and their complexity (Figure 3.19). We perceive the characteristics of sound waves as pitch, loudness, and timbre.
Pitch The tones (pitch) we hear depend on the frequency of sound waves. The number of waves per second corresponds to the speed of the vibratory event. A rapidly vibrating tuning fork will propagate more waves per second than one that is vibrating more slowly.
Number of waves per second is defined as frequency and is measured in Hertz units (Hz), named after a 19th-century German physicist, Heinrich Hertz. One Hertz unit cor- responds to one vibration per second. A normal human ear is sensitive to frequencies ranging from 16 Hz (16 waves per second) to 20,000 Hz (children hear higher frequencies
one cycle
sine wave greatest
expansion areas of greatest
compression of air (molecules)
Figure 3.18
A vibrating rod in slow motion. Successive illustrations demonstrate that the rod creates sound waves by alternately compressing and rarefying the surrounding molecules. The graph at the bottom illustrates the wave created by the vibrating rod.
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CHAPTER 3Section 3.4 Hearing
than adults; and women hear higher frequencies than men). A number of animals are sen- sitive to sounds considerably beyond those we perceive, the most notable probably being the dog, the bat, and the porpoise. The silent dog whistle is silent only because it creates vibrations in excess of 20,000 Hz. Porpoises and bats emit sounds in the range of 100,000 Hz, which they use for echolocation.
Loudness Loudness corresponds to the amplitude (intensity) of waves and is measured in decibels (dB units). Amplitude, defined physically as the vertical distance between wave peaks, corresponds to the violence of the vibratory event and is not constant throughout the wave field. That is, maximum amplitude occurs next to the source and decreases in an outward
a frequency (pitch)
b amplitude (loudness)
low frequency, high amplitude (low pitch, loud)
low frequency, low amplitude
(low pitch, soft)
high frequency, high amplitude
(high pitch, loud)
two separate (in time) waves perceived as
separate sounds
two waves combined to produce a single, more
complex sound
high frequency low amplitude
(high pitch, soft)
c complexity (timbre)
Figure 3.19
Sound waves differ from one another in three dimensions: pitch, which is a function of num- ber of waves per unit of time (frequency) (a); loudness, which is a function of the height of the wave (amplitude) (b); and timbre, which is a function of the individual frequencies of waves combined to yield a different subjective experience of sound (complexity) (c).
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CHAPTER 3Section 3.4 Hearing
direction. The closer you are to the falling tree, the louder it is. If you’re far enough away, does it even make a sound?
Zero dB has been arbitrarily set as the threshold for normal hearing given a tone of 1,000 Hz, loudness being in part a function of frequency (for example, tones below 100 Hz or above 15,000 Hz reach threshold at 40 dB or more). A sound 10 times louder is 10 dB; one 10,000 times louder is 40 decibels (104). In other words, perceived loudness increases logarithmically with increasing decibels. Exposure to sounds that are too loud can result in permanently impaired hearing (Figure 3.20).
Timbre Sounds are almost never pure but are instead a mixture of frequencies. Even a single note played on a piano has overtones—slightly different auditory waves. This wave complexity gives rise to perceived timbre and accounts in large part for the richness of auditory percep- tions. The same notes played on different musical instruments can usually be differentiated easily, especially by musicians and others who are familiar with the instruments. Similarly, human voices present great varieties of timbres. It is complexity of waves, rather than dif- ferences in frequency or amplitude, that allow us to discriminate between a whisper and the rustling of silk sheets, or between our mother’s voice and that of other mothers.
10
20
0
40
60
80
100
120
140
160
180
Rustle of leaves
Average whisper at 4 feet
A butterfly at 6 feet Butter melting
Night noises in city
Quiet automobile at 2 feet
Prolonged exposure dangerous
Hearing threshold
Pain threshold for humans
Highly probable hearing loss
Chainsaw; Power mower Screaming child
Loudest woman in British shouting concert
Electric guitars in rock concert
Siren at 20 meters
Shotgun Space shuttle launch
Source of sound Typical decibel value Consequences
Extremely loud
Loud
Quiet
Just audible
Figure 3.20
Loudness is measured in decibels. Zero decibels is the arbitrary value for the point below which a sound wave at 1,000 Hz will not be heard by most people. Sounds above 85 decibels can damage hearing with prolonged exposure. Sounds above 110 decibels are uncomfortable and even painful.
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CHAPTER 3Section 3.4 Hearing
The Auditory Apparatus
In your ear there is a complex arrangement of tubes, canals, containers, fluids, membranes, and nerves arranged as shown in Figure 3.21. For simplicity, scientists group these various components into three general areas: external ear, middle ear, and inner ear.
The external ear includes the pinna or auricle, the oval, creased, visible extremity on each side of the head, and the concha and auditory canal. Although three muscles attach each pinna to the head, the visible ears remain virtually immobile, unlike the ears of most nonhuman animals. At the center of the pinna is the concha, which spirals into the auditory canal, a circular tube approximately one-quarter inch wide and one inch long. At the end of this wax-filled canal is the tympanic membrane, commonly called the eardrum.
The middle ear consists of a small air-filled space called the tympanic cavity. Inside this cavity are the three minute bones (ossicles) popularly named after the objects they closely resemble: the hammer (malleus), the anvil (incus), and the stirrup (stapes). This last ossicle, the stapes, fits over a small membrane (oval window) that leads into the inner ear.
The inner ear is filled with a thin fluid contained in a spiral structure (the cochlea). Inside the cochlea is the basilar membrane, adjacent to which are the nerve cells that act as sound
pinna
bone
cochlea
basilar membrane (inside cochlea)
skin
auditory canal
concha
eardrum
tympanic cavity
stirrupirrupi
oval window
bone
vestibular nerve
semicircular canal hammer
anvil
auditory nerve
eustachian tube
e
Figure 3.21
The human ear is a complex arrangement of tubes, canals, containers, fluids, membranes, and nerves.
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CHAPTER 3Section 3.4 Hearing
receptors and translators. It is in the cochlea that waves are translated into neural impulses. The nerve cells in the cochlea are arranged in a line and are collectively labeled the organ of Corti. The organ of Corti is isolated from the blood supply. If this were not the case, we would be deafened by the roaring of our bloodstreams and the pounding of our pulses.
How the Ear Works The pinna gathers auditory waves and funnels them into the auditory canal toward the eardrum, which they set to vibrating much as an ordinary drum might vibrate, although the vibration is minimal. The vibration corresponds physically to the characteristics of the sound waves, which, in turn, are specific to the event that gave rise to them. The vibra- tions of the eardrum are transmitted to the three ossicles of the middle ear, which amplify them. The direct physical connection of the last of these ossicles, the stapes, to the inner ear sets up wavelike motions in the fluid in the cochlea. Receptors (hair cells) on the organ of Corti respond to these waves, initiating neural transmission via the auditory nerve to the auditory centers located in the temporal regions of the brain. Each ear feeds signals to both the right and left temporal lobes, much as each eye relays impulses to the visual cortex in both the right and left hemispheres.
From a physical point of view, functioning of the auditory perceptual system can be seen as involving the conversion of acoustic energy (auditory or sound waves) into mechanical energy at the tympanic membrane and through the ossicles, into hydraulic energy in the fluid of the inner ear, and finally into electrical energy at the organ of Corti (Figure 3.22).
anvil
stirrup
hammer cochlea
auditory nerve
electricalhydraulicmechanicalacoustic
Figure 3.22
Sensation involves the conversion of energy. This is most clearly demonstrated in the auditory system, but it occurs in other perceptual systems as well. The acoustic energy of sound waves is translated into mechanical energy as the tympanic membrane and the ossicles (hammer, anvil, and stirrup) vibrate. In the fluid of the inner ear, the mechanically transmitted energy is converted to hydraulic energy, which triggers an electrical impulse in the organ of Corti.
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CHAPTER 3Section 3.5 The Body Senses
One of the truly amazing features of this intricate conduction of vibrations is its fidelity. Wever and Bray (1930) demonstrated this phenomenon by inserting an electrode in the cochlea of an anesthetized cat, amplifying the signals picked up by this electrode, and transmitting them through a loudspeaker. Music that is fed into the cat’s ear can be trans- mitted in this manner with virtually no distortion. So finely tuned is this system, and so independent from other systems, that it is possible to do the same thing with a dead cat! But there are easier ways of listening to music.
3.5 The Body Senses
If you take a cat, hold it on its back a yard or so above the floor, and suddenly drop it, it will in all likelihood land on its feet. Most of us would not do so well. This righting reflex, present in many animals other than cats, illustrates the vestibular sense—the sense involved in balance and awareness of position. It, in combination with two other groups of body senses, the skin senses and the kinesthetic senses, provides us with information concerning the positions and movements of our body, our relationship to the gravitational plane, and sensations relating to touch, temperature, and pain.
The Vestibular Sense
There is in part of our inner ear an elaborate arrangement of canals and sacs not involved in hearing but in basic orientation. This vestibular organ consists of the semicircular canals and two adjoining fluid-filled enclosures, the utricle and the saccule. These enclo- sures contain a large number of hairlike sensory receptors.
You can get a rough idea of how the vestibular sense works by swirling a glass partly filled with water, moving it backward, forward, up, down, or sideways. In each case, movement of the water is highly predictable. Laying the glass on its side also has very predictable results. In much the same way, a heavier gelatinous mass in the fluid-filled enclosures of the vestibular organ responds to changes in movement or position. These changes are sensed by the receptors within the organ and are translated into neural impulses signal- ing, at a simple level, that you are upright, sideways, upside-down, moving, accelerating, stopping, stationary, or turning. Because of its location, the vestibular organ is particularly sensitive to movements of the head.
The Skin Senses
We are responsive to heat and cold, to pain, and to pressure (touch). The stimulation that gives rise to each of these sensations cannot be quantified physically as can acoustic or light waves. Nor has it been possible to identify specific types of sensors that respond to each of these different sensations. A number of very different nerve endings in the skin have been identified, and human bodies have been mapped with respect to areas that appear to be sensitive only to pressure, only to temperature, and only to pain. This led
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CHAPTER 3Section 3.5 The Body Senses
quickly to the belief that there were different receptors for each of these sensations. How- ever, microscopic examination of successive layers of skin tissue revealed that this belief was erroneous.
Several characteristics of skin sensation are worth noting. One is that those parts of the body that are most sensitive to pressure (touch) include the tongue and lips and the parts covered with hair or nails. The base of each hair follicle is served by a concentration of neural receptors, as are the bases of each fingernail. Very slight pressure on a nail or the very gentle bending of a whisker can easily be felt. Whiskers are relatively stiff, and their movement displaces and activates nerve cells at their base. This principle is evident in cer- tain rodents and in members of the cat family, whose long, stiff whiskers serve as explor- atory sense organs, enabling them to move quickly in near darkness and through small spaces with little fear of colliding with walls (Figure 3.23).
A second characteristic of touch sensitivity concerns the wide disparity among pressure receptors on the body. If you touch someone at two places on the back, he or she may detect only a single point of pressure even if the touches are as much as 3 inches apart. Two touches on the tongue, however, will be sensed as being distinct even if they are only a fraction of an inch apart.
An important feature of body sensations is that some are highly subject to habitua- tion and others aren’t. Habituation is what happens when the effects of a stimulus diminish or even disappear with continued exposure. For example, receptors habitu- ate very quickly to sensations of touch. If this weren’t the case, we would constantly be aware of the sensations caused by the clothing we wear, our hair, and other sources of stimulation. We habituate less easily to pain, however, a feature that has very high survival value. If we habituated easily to pain, many of us might find ourselves dying of minor causes.
Figure 3.23
Nerve cells at the base of stiff whiskers are exceptionally sensitive touch detectors.
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CHAPTER 3Section 3.6 The Chemical Senses
The Kinesthetic Senses
Close your eyes and then touch your nose with the index finger of either hand. It is not very difficult, even though you could not see what you were doing. That’s because your kinesthetic sense, relying on various receptors in muscles, tendons, and joints, provides you with information about your bodily position and movement. You rely on this pro- prioceptive sensation (sensation generated by and about your own body) for all motor activities, including things as simple as touching your nose and as complex as doing three flips with two twists in freestyle skiing or diving.
3.6 The Chemical Senses
For most animals, the chemical senses, which include olfaction and taste, are excep-tionally important: They depend on these senses to find food and mates, and often to escape from danger as well. We, on the other hand, tend to depend far more on vision and hearing.
The chemical senses are so called because they’re responsive to chemical properties of certain substances and gases. Within limits, this system allows us to detect the nature of materials that reach the mouth and nose, to discriminate among them, and to respond affectively (emotionally) by appreciating or not appreciating. They are part of what Gib- son (1966) labels the savor system. This system depends not only on olfaction and taste, but includes as well reactions to pain, temperature, and touch. The texture, consistency, temperature, appearance, and other physical properties of food affect our subjective reactions.
Olfaction
Olfaction is described as the most primitive sense because it is thought to have developed before many brain structures, including the thalamus. Accordingly, it is the only one of the senses whose signals are not routed to the brain via the thalamus.
Olfaction is not nearly as well developed in humans as it is in most nonhuman species. The part of the human brain dedicated to olfaction is minimal; in dogs, approximately one-third of the cortex is devoted to olfaction; and in many fish, the entire cortex is olfac- tory. As a result, the dog’s sense of smell may be up to a million times more sensitive than ours (Kidd, 2004). Dogs can be trained to find drugs, to detect gas leaks, to track fugitives, or to locate lost shoes.
We cannot do these things. We don’t even know how many odors we can reliably detect. Research in this area is difficult because “odor” is a subjective response; it isn’t a physical property of an object or of the gaseous molecules that emanate from it. It is also difficult because we don’t have an olfactory vocabulary. We are absolutely lost when we try to describe smells and almost always do so by reference to other smells or to objects that give rise to fairly typical smells. Can you describe a musky smell? A flowery smell? The differ- ence between the fragrance of a wild rose and a florist’s rose?
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CHAPTER 3Section 3.6 The Chemical Senses
Judging on the basis of our language, it would appear that we smell very imprecisely. But that may not be entirely true. Maybe we simply haven’t found it necessary or useful to speak of odors with our enemies or friends. But we do know intuitively what is pleasant and what isn’t. And the number of associations evoked by odors for which we have no names attests to the potential of our noses.
The Olfactory Organ We tend to think of our noses as our olfactory organs—which they really aren’t. But they do allow us to smell, and the fact that they point downward presents two distinct advan- tages in this regard. One is that a nose that points downward is less likely to become filled with rain, sleeping dragonflies, or other objects falling from the sky. The other is that odors frequently originate from warmer sources and therefore tend to rise.
In the course of breathing, the nose allows potentially odorous molecules to reach the true olfactory organs, the olfactory epithelia (singular: epithelium). These organs, directly con- nected to the olfactory regions of the brain by means of neural pathways, are found some distance up the nose, in each nostril. They are thin mucous membranes approximately the size of a dime (Figure 3.24). Their odor-sensitive cells are capable of regeneration in most vertebrates (Costanzo, 2005).
olfactory bulb
olfactory epithelium
Figure 3.24
It is not our nose that detects odors, but the olfactory epithelium inside each nostril. The epi- thelia are covered with tiny hair cells that change odors into nerve impulses that are passed on to the brain (olfactory bulb) through the olfactory nerve.
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CHAPTER 3Section 3.6 The Chemical Senses
Figure 3.25
Most receptors for taste are found along the top outer edges of the tongue. Researchers long believed that different areas of the tongue are most sensitive to distinct tastes. It is now gener- ally accepted that all five tastes (salt, sour, sweet, bitter, and umami) can be detected by taste buds on any part of the tongue.
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CHAPTER 3Section 3.7 Adding Pieces of the Puzzle
Taste
Taste is a subjective reaction to the chemical effects of certain substances that enter the mouth, together with effects related to odor, touch, temperature, and pain. The principal organ of taste has long been considered to be the tongue, but we know that olfaction is also closely involved. In fact, individuals with anosmia (those who cannot detect odors) are often unable to differentiate between foods that to others seem to taste quite different.
The cells sensitive to taste are located in taste buds on the tongue, with the greatest con- centrations along its outer, upper edges. These cells regenerate as often as every seven days, but with advancing age they do so less frequently or cease regenerating altogether (Carlson, 2007). This explains why very old people sometimes lose all ability to taste food and middle-aged people find they have to use more salt and spices to evoke the same subjective response.
For a long time, psychologists agreed that we can detect four distinct tastes and their com- binations: salt, sweet, sour, and bitter. More recently, a fifth basic taste has been added to the list: umami. This Japanese word means “pleasant savory taste.” It refers to the taste of the amino acid L-glutamate, which has long been used in a variety of dishes. Its flavor is described as a distinct meaty taste with a mild but lasting aftertaste (Yamaguchi, 1998).
There has been a long-lasting myth that various parts of the tongue are more or less sensi- tive to different tastes. Early tongue maps typically showed that the tip of the tongue was most sensitive to sweet tastes, a narrow band behind the tip responded to salt, the very back was most sensitive to bitter tastes, and sour tastes were detected by cells on each side of the tongue. However, more recent research indicates that this simplified view is incor- rect. It appears that all five tastes can be sensed by any part of the tongue (Collings, 1974). (See Figure 3.25.)
3.7 Adding Pieces of the Puzzle
This chapter began with a description of what might have seemed a simple situation: a person standing barefoot on the dew-chilled grass in early morning admiring an orchid, smelling the odor of bacon and coffee, hearing and recognizing the sounds of a voice.
But it isn’t a simple situation. To try to understand the richness and complexity of what was happening in that an instant, we had to analyze the situation and break it down into sections and subsections, each dealing with a different facet of the whole. But even though we were forced to look at each of our sensory systems separately, we should not lose sight of the fact that these function simultaneously and in coordination with each other. What happens in our minds at any given time is seldom limited only to what we see at that very moment—or to what we hear, or smell, or taste. Knowing how each of these systems functions gives us some important pieces of the human puzzle. But we need to put them together to understand the final picture.
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CHAPTER 3Main Points
Main Points
1. Sensation and Perception: Sensation is the response of our senses to stimulation; perception is the brain’s interpretation of sensation.
2. Vision: Light-sensitive cells in the rods and cones of the retina respond to the characteristics of light waves, translating them into neural impulses that the brain interprets in terms of hue (corresponding to wavelength), intensity (corre- sponding to amplitude), and purity (corresponding to complexity). Rods respond to brightness and are used mainly for night vision; cones respond to color and are used mainly in daytime. What we see is often determined by what we have learned and expect, as is evident in the visual constancies.
3. Attention and Perception: We are conscious of only a fraction of all stimulation. Much of what we are not aware of is nevertheless available for a brief period.
4. Hearing: The auditory system permits us to locate sounds, to identify them, and to communicate. The hearing apparatus (outer, middle, and inner ear) translates waves caused by vibratory events into mechanical energy, hydraulic energy, and finally electrical nerve impulses that the brain interprets in terms of differences in pitch (corresponding to frequency), loudness (corresponding to amplitude), and timbre (corresponding to complexity).
5. The Body Senses: These include the vestibular sense (inner ear semicircular canals, responsible for balance and sensing movement); the skin senses (sensors responsive to pain, temperature, and touch); and the kinesthetic senses (muscle, joint, and tendon sensors, providing information about bodily position and motion).
6. The Chemical Senses: These respond to the chemical properties of volatile substances (olfaction, where the olfactory epithelia in each nostril respond to odorous molecules for which we have a loose and inadequate vocabulary) and to the chemical properties of substances that come in contact with taste buds on our tongues, giving rise to one or more of five distinct tastes: sour, sweet, salty, umami, and bitter.
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CHAPTER 3Main Points
adaptation
afterimage
amplitude
anosmia
attention
body sense
chemical senses
cocktail party phenomenon
complexity
cones
cornea
decibels
frequency
habituation
Hering’s opponent process theory
iris
kinesthetic senses
lens
nanometers
olfaction
olfactory epithelia
optic nerve
perception
phi phenomenon
photons
pinna
proprioceptive sensation
pupil
retina
rods
sensation
skin senses
sound waves
umami
vestibular organ
vestibular sense
visual constancies
wavelength
Young-Helmholtz trichromatic theory
Study Terms
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4
Learning
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • How is learning defined? • What is behaviorism? • How do classical and operant conditioning differ? • How do the various schedules of reinforcement affect behavior? • What experimental findings present significant problems for behavioristic
explanations? • What are the main beliefs of cognitive psychology? • What is reciprocal determinism? • How can learning principles be applied to real life?
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CHAPTER 4Learning
Uncle Abner said that the person that had
took a bull by the tail once had learnt
sixty or seventy times as much as a person
that hadn’t. —Mark Twain,
Tom Sawyer Abroad, 1894
Chapter Outline
4.1 What Is Learning? Approaches to Learning
4.2 Behavioristic Approaches Classical Conditioning Operant Conditioning Schedules of Reinforcement
4.3 A Transition to Cognitivism Problems for Traditional Behaviorism Insight
4.4 Cognitive Approaches The Main Beliefs of Cognitive Psychology Bandura’s Social Cognitive Theory
4.5 Practical Applications of Learning Principles Applications of Behaviorism Applications of Cognitivism
My grandfather once took a bull by the tail as my cousins and I watched from the other side of the split-rail fence. He was trying to get him into the chute so he could load him on the truck and take him over to have a go at Mr. Tremblay’s cows.
Grandpa’s bull wasn’t real anxious to get into that chute. He ignored all the little piles of oats cleverly pointing up into the truck; he refused to be led by rope or coaxed from behind; and when grandpa “sicced” the dog on him, the bull snorted and the dog went yelping through the gap between the rails.
So Grandpa hitched up his pants and spat on the ground and then he took the bull by the tail and turned him to face the chute and yelled, “Git!” and the bull took four or five quick steps and it looked like he was gonna git right straight up the chute and we thought wow, grandpa’s a smart one . . .
But no, quick as you can spit, the bull yanked his tail out of grandpa’s hands, whirled around, low- ered his head, and lifted my grandpa clear over the fence.
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CHAPTER 4Section 4.1 What Is Learning?
4.1 What Is Learning?
Had our grandfather learned 60 or 70 times as much as a guy who never grabbed a bull by the tail? Maybe. Certainly, he learned not to grab a bull by the tail. And he also learned, as we found out the next day, that if you put a handsome cow in the truck to begin with, you don’t have to grab the bull by the tail or sic the dog on him: He’ll just sashay right up into the truck by himself.
Learning, psychology tells us, consists of changes in behavior—changes like no longer grabbing a bull by the tail. But not all changes in behavior are examples of learning. Some changes are temporary; they might result from fatigue or from the use of drugs. Other changes appear to be mainly due to physical maturation; still others might result from injury or disease of the brain or other parts of the nervous system.
Learning is defined as relatively permanent changes in behavior that result from experience but are not caused by fatigue, maturation, drugs, injury, or disease (Figure 4.1). Strictly speaking, however, it is not the changes in behavior themselves that define learning; the changes are simply evidence that learning has occurred. Learning is what happens to the organism as a result of experience.
Although we look at behavior—at actual performance—for evidence that learning has occurred, changes in behavior are not always apparent following experiences that might be presumed to have led to learning. In many cases there will be no evidence of learning until an opportunity to display a behavior is presented; and in some cases, that opportunity may never occur. For example, you might have learned a particularly clever way of blowing your nose after seeing someone else blow theirs. But that does not mean that you will ever perform the trick. It might forever remain latent (meaning potential but not apparent).
Approaches to Learning
Learning is not easily separated from other major topics in psychology. Changes in behav- ior are centrally involved in many aspects of psychology, including motivation, person- ality, perception, development, and even mental disorders. We are not simple, highly predictable organisms with static and unchanging patterns of behavior. It is only fools who don’t profit from experience, and we are not fools; we are Homo sapiens, the wise one. We profit from experience— and that defines learning.
Not surprisingly, most of the first psychologists to look for pieces of the human puzzle devoted considerable effort to discovering the laws and principles of learning. As we saw in Chapter 1, these early efforts, especially in the United States, rejected the more philosophical and intuitive approach of an earlier age. Instead, they embraced
Learning is a change in behavior (or in potential for behavior) as a result of experience. Like learning not to grab a bull by the tail.
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CHAPTER 4Section 4.1 What Is Learning?
a scientific approach—an approach concerned mainly with the objective and observable aspects of human functioning. The most important pieces of the puzzle, they thought, would have to do with the rules that govern relationships between stimuli (observable conditions that can give rise to behavior) and responses (actual, observable behavior).
Because they deal with observable behaviors, the theories that resulted are labeled behavior- istic theories. Sometimes they’re also referred to as S-R or associationistic theories because they deal mainly with associations between stimuli and responses. And although they have sometimes been accused of leading to a mechanistic and incomplete description of human learning, they have contributed a great deal to our understanding that continues to be both valid and valuable.
A second major group of learning theories are cognitive theories. They’re concerned less with the objective aspects of behavior than with more mental processes such as thinking, imagining, anticipating, problem solving, decision making, and perceiving.
Learning All relatively permanent changes in behavior that
result from experience but are not due to fatigue,
aging, maturation, drugs, injury, or disease.
Change in Behavior
Actual or potential changes following
experience.
Experience
Exposure to stimuli
Figure 4.1
Evidence of learning is found in actual or potential changes in behavior as a result of experience. But learning itself is an invisible, internal neurological process.
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CHAPTER 4Section 4.2 Behavioristic Approaches
4.2 Behavioristic Approaches
History is a strange and often unjust lady. You see, an American with the melodic name Edwin Twitmyer was actually the first person known to have reported the principle of classical conditioning. He discovered it while doing research for his doctoral dissertation, publishing his findings in 1902. In 1904, he even presented these findings to the Ameri- can Psychological Association (when William James was its president) as a paper entitled “Knee Jerks without Stimulation of the Patellar Tendon” (Twitmyer, 1905). But nobody paid any attention.
Classical Conditioning
And then about a year later, a Russian by the name of Ivan Pavlov presented essentially the same findings—only he had used dogs as subjects whereas Twitmyer had used humans. Nobody knows Twitmyer’s name today, but everybody knows Pavlov’s.
Ironically, the discovery that made Pavlov so famous came about almost by accident. Pavlov was a physiologist, not a psychologist, and at the time of his lucky discovery, he was busily investigating and measuring secretions related to digestion. That’s when he noticed that some of his more experienced dogs began to salivate whenever they saw their handlers. The less experienced dogs also salivated, but only when given food.
Pavlov rightly guessed that his older dogs had learned something that the more naive dogs had yet to learn: They had learned to associate the sight of a handler (stimulus) with food (Figure 4.2). But only one of these stimuli, food, would normally lead to salivation. So, in a sense, what the dogs had learned was to substitute one stimulus (handler) for another (food). Not surprisingly, this kind of learning is sometimes called learning through stimulus substitution; its more common label is classical conditioning.
That the dog has learned something is clear: there has been a change in behavior (spe- cifically, in the response to the handler) as a result of experience (repeated pairing of the handler and food). That is, a previously neutral stimulus (sight of handler) now leads to a response ordinarily associated with another stimulus (food). This defines classical conditioning.
Pavlov’s Experiments To clarify the laws of classical conditioning, Pavlov devised a series of experiments (Pav- lov, 1927). In the best known of these, a dog is placed in a harness-like contraption similar to the one shown in Figure 4.3. The apparatus allows food powder to be inserted directly into the dog’s mouth or to be dropped into a dish in front of the dog. The salivation that occurs when food powder is placed in the dog’s mouth is an unlearned response and is therefore an unconditioned response (UR). The stimulus of food powder that gives rise to the UR is an unconditioned stimulus (US).
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CHAPTER 4Section 4.2 Behavioristic Approaches
Figure 4.3
Pavlov’s dogs were placed in harnesses such as the one shown on the left. Saliva dropping through the tube activates the balancing mechanism so that the amount of salivation is recorded on the revolving drum. In this demonstration, presentation of food is paired with a light that shines through the window.
Figure 4.2
What Pavlov first noticed was that the sight of the handler was enough to cause experienced dogs to salivate. He later paired other stimuli, such as bells and buzzers, with the presentation of food to study the details of classical conditioning.
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CHAPTER 4Section 4.2 Behavioristic Approaches
Most animals, including humans, are born with a number of these simple, prewired (mean- ing they don’t have to be learned) stimulus-response associations called reflexes. More com- plex behaviors that are also unlearned are instincts. That we blink when something brushes our eye is a reflex—as is our tendency to salivate in response to food, to withdraw from painful stimulation, and to jerk the knee in response to a sharp blow below the kneecap.
In Pavlov’s conditioning demonstration, the trainer arranges for a buzzer to sound as food powder is inserted into the dog’s mouth. This procedure is repeated a number of times. After a while, the trainer simply sounds the buzzer without providing any food powder. And the dog still salivates. The animal has been conditioned to respond to a buzzer, termed a conditioned stimulus (CS), by salivating, a conditioned response (CR) (Figure 4.4).
Acquisition Several factors are directly related to the ease with which a classically conditioned response can be acquired. One is the distinctiveness of the CS. Not surprisingly, a stimulus that is eas- ily discriminated from other stimulation will more easily become associated with a response.
NS
Buzzer
BEFORE CONDITIONING
US
Food UR
Salivation
• elicits No response (or neutral response)
• elicits
CS
Buzzer
AFTER CONDITIONING
CR Salivation
• elicits
CS
Buzzer
CONDITIONING PROCESS (REPEATED SIMULTANEOUS PAIRING)
US
Food UR
Salivation • elicits
Figure 4.4
Classical conditioning. Initially, the stimulus (buzzer) does not elicit salivation. After repeated pairings of this stimulus with the unconditioned stimulus (food), the buzzer has become a conditioned stimulus that now elicits a conditioned response (salivation).
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CHAPTER 4Section 4.2 Behavioristic Approaches
A second critically important factor is the temporal relationship between the conditioned and the unconditioned stimulus. The ideal situation, delayed (or forward-order) condition- ing, presents the conditioned stimulus before the unconditioned stimulus, with the CS continuing during the presentation of the US (Hussaini, Komischke, Menzel, & Lachnit, 2007). In the classical Pavlovian experiment, for example, fastest learning occurs when the buzzer sounds just before the presentation of food powder and continues while the food powder is injected into the dog’s mouth. Other alternatives are to have the CS begin and end before the US, termed trace conditioning; to present the US and the CS simultaneously (simultaneous conditioning); or to present the US prior to the CS (backward conditioning). Figure 4.5 summarizes the relationship of these temporal factors to classical conditioning.
As noted, fastest learning typically occurs when the conditioned stimulus precedes the unconditioned stimulus (forward-order conditioning). The opposite situation, backward conditioning, in which the conditioned stimulus follows the unconditioned stimulus, has generally not resulted in learning except under very specific circumstances. For example, presenting a dog with food and then later ringing a bell does not normally lead the dog to salivate in response to the bell.
Backward conditioning can sometimes be effective, however. For example, Minnier, Mis- anin, and Hinderliter (2007) successfully conditioned taste aversions in rats by injecting them with lithium chloride (which makes them sick—a US) either 15 or 45 minutes before
Delayed
Trace
CS
US
CS
US
Simultaneous
Backward
CS
US
CS
US
TIMELINE
On Off
Figure 4.5
Unconditioned stimulus (US)–conditioned stimulus (CS) pairing sequences are shown here in the order of effectiveness. Conditioning takes place most quickly in the delayed sequence where the CS (buzzer) precedes the US (food powder) and continues throughout the time the US is presented.
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CHAPTER 4Section 4.2 Behavioristic Approaches
they were allowed to drink sweetened water (the CS). Most rats who experienced the 15-minute delay later avoided the sweetened water.
Keith-Lucas and Guttman (1975) conditioned rats to avoid a plastic toy by shocking them electrically and then placing a plastic hedgehog-like toy in their cages. A significant num- ber of rats exposed to the hedgehog 1, 5, or 10 seconds after receiving an electric shock displayed avoidance behavior the following day. Backward conditioning had been estab- lished after a single trial—unlike Pavlov’s dog, who required many trials before learning.
The significance of these results is not simply that they illustrate that backward condi- tioning can be accomplished. More important, they illustrate that many organisms have biological predispositions to learn behaviors that have survival value. Rats are prepared to learn to avoid strange objects such as plastic hedgehogs. And many preyed-upon ani- mals, as Griffin and Galef (2005) point out, are highly prepared to learn about predators. That a warbler flies like the devil when a dark shadow sweeps by may well be because the shadow has previously been preceded by signs of alarm among other warblers, one of whom might have succumbed to a swift-flying merlin or a sharp-shinned hawk. And, as we saw in Chapter 2, humans seem to be prepared to learn strong taste aversions—which is useful when the tastes you learn to avoid belong to objects that might kill you if you ate them. Similarly, many people acquire fear of snakes, insects, and other potentially danger- ous creatures relatively easily (Öhman et al., 2007).
Generalization and Discrimination A dog trained to salivate in response to a buzzer may also salivate in response to a bell, a gong, or a human imitation of a buzzer. This phenomenon is called stimulus generalization. It involves making the same responses to different but related stimuli. An opposite phenome- non, stimulus discrimination, involves making different responses to highly similar stimuli.
Watanabe (2010) conditioned a group of pigeons by reinforcing them when they pecked at paintings that human judges had labeled “good” and not reinforcing them when they pecked at others judged “bad.” When these pigeons were later shown new paintings, they generalized what they had learned, pecking the “good” paintings far more often than the “bad.” As Watanabe puts it, “the results showed that pigeons could discriminate novel ‘good’ and ‘bad’ paintings” (2010, p. 75).
Extinction and Recovery Many classically conditioned responses are remarkably durable. A dog conditioned to sal- ivate in response to a tone and then left to do nothing but dog things for many months will immediately salivate when he is brought back into the laboratory and he hears the bell.
But classically conditioned responses can be eliminated—a process called extinction. Extinction requires that the experimenter present the conditioned stimulus repeatedly without the unconditioned stimulus. For example, if Pavlov’s well-conditioned dog heard the tone repeatedly but it was never again paired with food, it would soon stop salivating in response to the tone.
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CHAPTER 4Section 4.2 Behavioristic Approaches
Once a classically conditioned response has been extinguished, it can be reacquired much more easily than was initially the case. A dog who has learned to salivate in response to a tone and whose conditioned response is later extinguished will learn to salivate again after only one or two pair- ings of tone and food powder. In fact, an extin- guished response sometimes recurs in the absence of any training. This phenomenon, termed sponta- neous recovery, illustrates that behaviors that are apparently extinguished are not necessarily com- pletely forgotten.
Contiguity When I was 5 years old, my grandfather’s dog bit me. I remember it as a vicious attack, although I suspect it really wasn’t that bad. I haven’t been
bitten by a dog since, and I have raised and loved various dogs.
But last week my truck broke down on the way to the lake and I had to walk into a farm- yard for assistance. When the farm dog came bounding across the field, barking, I tasted fear, as I have on many other occasions since I was 5. I’m conditioned to fear strange dogs. I have no control over my physiological reactions when I meet one.
Why does an emotional (or other) response such as fear become conditioned to a particu- lar stimulus (or class of stimuli)? Pavlov’s explanation is that the simultaneous or near- simultaneous presentation of a stimulus and a response leads to the formation of a neural link between the two. In this view, what is most important in the conditioning situation is the contiguity (closeness in time) of the stimulus and response. A contiguity explanation of classical conditioning maintains that the stimuli associated with “dog” (appearance, smell, sound, movement) were also associated with my initial fear response. Thus the sight, sound, or smell of a dog continues to plague me in my otherwise peaceful adult life.
Blocking Although contiguity might appear to be an adequate explanation for what happened to Pavlov’s dogs, and perhaps for my fear of strange dogs, there are some relatively sim- ple experimental situations that it does not explain. For example, Kamin (1969) paired a noise and a light (two unconditioned stimuli) with electric shock (a conditioned stimulus) administered to the feet of a group of rats (we’ll call them the A group). In this study, the light and noise were turned on, and immediately afterwards the rats were shocked. Clas- sical conditioning theory would clearly predict that after the light and noise are paired often enough with the shock, either the light or the noise alone would cause an avoidance reaction in the rat. The prediction is correct.
But now Kamin threw a twist into the procedure. First he conditioned a group of rats by pairing only noise and electric shock (this is the B group). Then, once these rats showed a
Classical conditioning is sometimes a good explanation for unconscious emo- tional learning—like acquiring a fear (or a love) of dogs.
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CHAPTER 4Section 4.2 Behavioristic Approaches
well-conditioned fear response to the noise, he conditioned them exactly as he had the A group, this time pairing both light and noise.
Recall that the A-group rats responded with fear to both the light and the noise. The B group rats also responded with fear to the noise. Strikingly, however, they showed no fear in response to the light in spite of the fact that they were conditioned in exactly the same way as the A group—but only after they had already been conditioned to the noise alone. It seems that for the B-group rats, learning that noise means shock blocked them from learning that light might also mean shock—a phenomenon appropriately labeled blocking (Figure 4.6).
Contiguity does not explain blocking. Clearly, if conditioning depends only on the simul- taneous presentation of stimulus and response, there is no reason why both groups of animals should not have learned the same things.
One explanation for blocking is this: Whenever something new happens to an animal, it immediately searches its memory to see what events could have been used to predict it. When a lynx leaps at a rabbit and narrowly misses, the terrified rabbit scans its memory banks for immediately preceding events. Maybe it remembers a looming shadow, the thudding of padded footfalls, the stink of hungry lynx. And forever after, it flees from footfalls and shadows and hot stenches.
So when a rat receives a mild foot shock, it scans its memory to see what just preceded the event. The A-group rat notes that both light and noise always come before the shock, and so it freezes whenever it hears the noise or sees the light. But the B-group rat, who already knows that noise means shock, learns absolutely nothing new when later exposed to both
Pretraining
None Noise + Light Shock Freezing (high fear) Freezing (high fear)
Noise Shock Noise + Light Shock Bar pressing (no fear) Freezing (high fear)
Conditioning Testing with light Testing with noise
A G
ro u
p (
C o
n tr
o l)
B G
ro u
p (
B lo
ck in
g )
Figure 4.6
Kamin’s study of blocking. A-group rats, exposed to both noise and light followed by a shock, subsequently react strongly to the light alone. But B-group rats, who have previously learned that noise means shock, fail to learn that light might also mean shock.
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CHAPTER 4Section 4.2 Behavioristic Approaches
noise and light followed by shock. Once the rat has learned that noise means shock, it no longer needs to pay attention to other stimuli.
Consequences Learning is a fundamentally adaptive process: Changes in behavior are what allow organ- isms to survive. Clearly, we, like any other animal, need to remember what is edible and where to find it; we need to recognize potential enemies; we need to stay away from elec- tric shocks. Put another way, we have to learn what goes with what—what the most likely outcomes of our behavior are.
One explanation for classical conditioning says, in effect, that what is learned is not a simple pairing of stimulus and response as a function of contiguity, but the establish- ment of relationships between stimuli. This explanation holds that what is important in a conditioning situation is the information a stimulus provides about the probability of other events. When a dog salivates in response to a tone, it is because the tone now pre- dicts food. In the blocking experiments, animals who have learned that stimulus A means shock find it difficult to learn that B also means shock. That’s because when A and B are subsequently paired, there is no new information provided by stimulus B.
Operant Conditioning
Classical conditioning theorists were not especially concerned with consequences; they studied relationships among stimuli and responses. But a second form of conditioning, operant conditioning, is built around the importance of behavior’s consequences. Operant conditioning is closely associated with B. F. Skinner (1953, 1969, 1971, 1989), one of the most influential psychologists of this age. He dealt with a large and important piece of the puzzle.
Skinner noted that although classical conditioning explains some simple forms of learning where responses are associated with observable stimuli (termed respondent behavior), most of our behaviors are of a different kind. Behaviors such as walking, jumping, listen- ing to music, writing a letter, and so on are more deliberate; they are seldom associated with a specific stimulus the way salivation might be. These behaviors appear more volun- tary. Skinner calls them operants because they are operations that are performed on the environment rather than in response to it. Classical conditioning does not provide an easy explanation for behaviors such as deciding to go for a walk or, at a simpler level, a dog learning to sit or roll over.
The Skinner Box In his investigations, Skinner used a highly innovative piece of equipment now known as a Skinner box. Typically, this experimental chamber is a small, cagelike structure with a metal grid for a floor. At one end is a lever; above it, a light; below it, a small tray. Outside the structure are various mechanical or electronic devices designed so that if the lever inside the cage is pushed down, the light will go on, a click will be heard (if someone is listening), and a food pellet will drop into the tray.
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CHAPTER 4Section 4.2 Behavioristic Approaches
When a naive rat is placed in this box, it does not respond as predictably as a dog in Pavlov’s harness. Its behaviors are more deliberate, perhaps more accidental. It does not know about Skinner boxes and food trays. It needs to be magazine trained. In a typical magazine training session, the experimenter depresses a button that releases a food pellet into the tray. At the same time, there is an audible clicking sound. Eventually the rat is drawn to the tray, perhaps by the smell of the pellet, perhaps only out of curiosity. Now the experimenter releases another food pellet, the rat hears the click, eats the pellet, hears another click, runs over to eat another pellet . . . In a very short period of time, the rat has been magazine trained.
Now the experimenter stops rewarding the rat unless it depresses the lever near the food tray. Most rats will eventually do so in the course of sniffing around and exploring. And when they do, they hear the telltale click and immediately rush over to the food tray. Very shortly, the rat will have learned to depress the lever. And if a light is paired with the pre- sentation of food, the rat may eventually learn to depress the lever simply to see the light go on (Figure 4.7).
The Basic Operant Conditioning Model All of the basic elements of Skinner’s theory of operant conditioning are found in the rat- in-Skinner-box demonstration. The bar pressing is an operant—an emitted behavior. The food is a reinforcer; reinforcement is its effect. Any stimulus (condition or consequence) that increases the probability of a response is said to be reinforcing. In the Skinner box the light, too, may be a reinforcer.
Time
R es
p o
n se
s
Figure 4.7
The photo shows B. F. Skinner with a rat in a Skinner box. The graph is a typical learning curve recorded on a revolving drum. The drum revolves at a constant speed, and each depression of the lever causes the recording pen to move up a notch. Steepness of the curve reveals response rate.
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CHAPTER 4Section 4.2 Behavioristic Approaches
What happens to a rat in the Skinner box may be described simply: A naive rat placed in this situation eventually emits a specific operant (bar pressing); the operant is reinforced; the probability of the operant occurring again increases with each reinforced repetition. When placed in the same situation on another occasion, the rat may begin to emit the operant immediately. The rat has learned associations not only between the operant and reinforcement, but also between the operant and specific aspects of the situation—called discriminative stimuli (SD).These discriminative stimuli might include things such as the sight and smell of the inside of the cage. They are stimuli that allow the rat to discriminate between this situation and others where the operant is impossible or will not be rein- forced. To some extent, the operant is now controlled by discriminative stimuli as well as by its consequences.
In brief, Skinner’s explanation of learning is based not on associations that might be formed between stimuli as a function of their co-occurrence (classical conditioning), but on associa- tions that are established between a behavior and its consequences. Any other distinctive stimulus that happens to be present at the time of those consequences may also come to be associated with the operant.
The basic law of operant conditioning is the law of effect, first proposed by Edward Thorn- dike (1898). This law states that behaviors that are followed by reinforcement (Thorn- dike called them “satisfying states of affairs”) are more likely to be repeated. Conversely, behaviors that are not followed by reinforcement (that lead to “annoyers,” in Thorndike’s words) are less likely to reoccur.
Shaping If you wanted to train a rat to depress a lever, you might not have to do much more than sit by the Skinner box and watch while the rat sniffs around, eventually depresses the lever, eats, depresses the lever again, eats, and on and on. In short order, your rat will rush over and begin working the lever as soon as you put it in the cage.
But what if someone asked you to train a cow to sit on a chair? Do you think, if you put a chair in the cow’s pen, she might eventually sit on it and you could then reward her with a nice bale of timothy hay?
Not too likely. But operant conditioning does suggest a way of teaching animals very com- plex behaviors. This is done by reinforcing small sequential steps in a chain of behaviors that will ultimately lead to the desired final behavior—a process called shaping. The ani- mal (or person) does not learn a complete final response at once, but is reinforced instead for behaviors that come progressively closer to that response—hence the phrase differential reinforcement of successive approximations. Using shaping techniques, pigeons have been taught to bowl, chickens to play baseball, mules to dive into shallow waters from precari- ous heights, and pigs to point pheasants.
Shaping can be a useful technique for toilet-training infants. For example, in the first phase of a potty-training study described by Smeets, Lancioni, Ball, and Oliva (1985), whenever infants “strained” as though they were about to soil their diapers, mothers or research assistants tapped on a nearby potty and called or touched the infant. This first
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CHAPTER 4Section 4.2 Behavioristic Approaches
phase of the shaping procedure was designed to draw the child’s attention to the potty and to reinforce the infant for paying attention to it— after which the infant was placed on that piece of equipment.
In the second phase, the potty was kept within reach of the child so that when signs of imminent defecation or urination appeared, the infant could be guided to grab the potty before being placed on it. And in the third phase, the potty was placed further away so that self-initiated movement toward the potty could be reinforced. By then, many of the infants had learned to crawl toward the potty.
Throughout all three phases, mothers and atten- dants reinforced the infants, primarily through smiling, verbal praise, and other gestures of approval. And all were toilet trained before they had learned to walk.
Schedules of Reinforcement
Skinner’s primary interest had been with discov- ering the relationships between behavior and its consequences. His investigations with rats and pigeons quickly revealed that the way in which reinforcement is given (the schedule of reinforcement) is an important factor in determining responses.
The experimenter has several alternatives: Every correct response (called a “trial”) might be rein- forced (continuous reinforcement) or only some responses might be (partial or intermittent reinforce- ment). In turn, partial reinforcement can be based on a proportion of trials (ratio reinforcement) or on the passage of time (interval reinforcement). Fur- thermore, reinforcement can be regular (fixed), or irregular (random or variable) (Figure 4.8).
Effects of Different Schedules The effects of different schedules of reinforcement are evident in three different dependent variables: rate of learning (acquisition rate); rate of respond- ing; and rate of forgetting (extinction rate). The
Nope, you can’t get me to fetch a stick or read a book. Those aren’t things we cows do! It seems that organisms are biologically “prepared” to learn certain things and not others.
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CHAPTER 4Section 4.2 Behavioristic Approaches
independent variable in studies of operant conditioning is the experimenter’s control of reinforcement (the schedule of reinforcement).
Initial learning—that is, rate of acquisition—is usually more rapid when every correct response is reinforced (a continuous schedule). If only some responses are reinforced (intermittent schedule), learning tends to be slower and more haphazard.
Random ratio For example, an average of
one out of every five
correct responses is rewarded at
random times
Fixed ratio For example,
every fifth correct response
is reinforced
Every correct response is reinforced
Intermittent (partial)Continuous
Random ratio For example, reinforcement
follows a correct response an
average of once every fifteen
seconds, but at unpredictable
times
Fixed interval For example,
the first correct response is
rewarded after a fifteen-second
time lapse
Ratio Interval
Figure 4.8
Schedules of reinforcement. Each type of schedule tends to generate a predictable pattern of responding.
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CHAPTER 4Section 4.2 Behavioristic Approaches
If, after initial learning, the experimenter continues to reinforce every correct response with food, the animal may respond at a high rate for a while, but will eventually become satiated and stop responding. Hence, the best training combination for an animal is usu- ally a continuous schedule initially, followed by an intermittent schedule.
With intermittent schedules, rate of responding seems to be closely tied to expectations the animal might develop about how and when it will receive reinforcement. For example, under variable schedules, when it is difficult to predict when the reward will occur, rate of responding tends to be high and relatively unvarying. But under a fixed-interval sched- ule, when reinforcement occurs after the first correct responses following a predetermined time lapse, rate of responding tends to drop off dramatically immediately after reinforce- ment and picks up again just before the end of the time interval (Figure 4.9).
Rate of extinction, which is the cessation of a response following withdrawal of reinforce- ment, is also a function of schedule of reinforcement. Extinction is typically more rapid with a continuous schedule than with intermittent schedules. And of the intermittent schedules, variable ratio schedules typically result in the longest extinction times—a fact that has not escaped the attention of slot-machine programmers. Skinner reports the case of one pigeon that, after complete withdrawal of reinforcement, emitted more than 10,000 pecks before extinction was complete.
Types of Reinforcement The fact that a pigeon would wear its beak to a frazzle before giving up an apparently unre- inforced behavior may be evidence that reinforcement is not nearly as simple or as obvious as these few pages might suggest. We really have no basis for concluding that pecking itself is not a rewarding activity for the pigeon and that it requires no extrinsic reinforcement to be maintained. As we saw in Chapter 2, pigeons are biologically programmed to peck—as
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Idealized graphs showing the effects of two reinforcement schedules on rate of responding.
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CHAPTER 4Section 4.2 Behavioristic Approaches
pigs are to root and humans are to explore. These activities don’t necessarily require extrin- sic reinforcement.
Extrinsic reinforcement includes the variety of external stimuli that might increase the probability of a behavior. In contrast, intrinsic reinforcement may be loosely defined as satisfaction, pleasure, or reward that is inherent in a behavior and that is therefore inde- pendent of external rewards. The satisfaction that people sometimes derive from their work is a form of intrinsic reinforcement; the money and the praise that might also result are forms of extrinsic reinforcement.
Skinner distinguishes between two broad classes of reinforcers. Primary reinforcers are stimuli that are rewarding for most people, most of the time, without anybody having had to learn that they are rewarding. They include food, drink, sleep, comfort, and sex.
Secondary reinforcers include the wide range of stimuli that may not be reinforcing ini- tially but that eventually become reinforcing as a function of having been associated with other reinforcers. Thus, secondary reinforcers are learned; primary reinforcers are not. Social prestige, praise, money, and applause are very powerful secondary reinforcers.
In general, reinforcement is any stimulus (situation) that increases the probability of a response occurring. If the stimulus increases the probability of a behavior it follows, it is a positive reinforcer. Food pellets in the rat’s cage are examples of positive reinforcers. So is the applause a performer receives, the money a worker gets paid, and the satisfaction a student gets from learning.
But some reinforcers are effective not when they are added to a situation, but rather when they are removed. For example, if a mild electric current is turned on in the rat’s cage and then is turned off when the rat depresses the lever, the result might be an increase in the probability that the rat will subsequently press the lever. In this case, turning off the electric current is an example of a negative reinforcer. In much the same way, the removal of pain might be a negative reinforcer for taking some medication, even as the alleviation of with- drawal symptoms might be a negative reinforcer for continued drug use.
The important point is that reinforcement is defined in terms of its effects rather than in terms of the characteristics of the reinforcing stimuli used. And the effect of reinforcement, by defini- tion, is to increase the probability of a behavior. A positive reinforcer does so when it follows a behavior; a negative reinforcer does so when it is removed following a behavior.
Operant conditioning is based on the consequences of behavior. They can be positive and reinforcing, as when this young lad is given his medal. Or they can be negative, as this driver is discovering.
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CHAPTER 4Section 4.2 Behavioristic Approaches
Punishment Negative reinforcement is often confused with punishment, although the two are quite different. Negative reinforcement increases the probability of a response; the intended effect of punishment is precisely the opposite.
In essence, the consequences of behavior can involve the removal or presentation of stim- uli that are pleasant or unpleasant (noxious). This presents the four distinct possibilities that are relevant to operant learning: positive reinforcement, negative reinforcement, and two types of punishment (Figure 4.10). There are countless illustrations of each of these possibilities in human behavior: Josephine is complimented on a new hairstyle (the addi- tion of a pleasant stimulus; positive reinforcement); a pill relieves Norbert’s headache (removal of an unpleasant stimulus: negative reinforcement); Arnaldo is reprimanded for losing his homework (addition of an unpleasant stimulus: punishment); Ronald has his jelly beans confiscated for throwing one in the goldfish bowl (removal of a pleasant stimulus; punishment).
The Ethics of Punishment Is punishment ethical? Is it even effective? Or does it just teach us to be sneakier? Psychol- ogy offers some tentative answers.
First, punishment is not always effective in eliminating undesirable behavior. Certainly, it is not nearly as effective as reinforcement is in bringing about more desirable behavior.
Punishment
[Bobby is given detention for talking
in class]
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(reward)
[Bobby is given 10 bucks for getting an A in math]
Added to the situation after
a response
Pleasant Stimulus (Appetitive)
Unpleasant Stimulus (Aversive)
Taken away from a situation after
a response
Negative reinforcement (relief)
[Bobby is let out of detention when he
promises to be quiet]
Punishment
[Bobby has his ten dollars taken away
for painting his sister]
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Figure 4.10
Reinforcement and punishment.
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CHAPTER 4Section 4.2 Behavioristic Approaches
Second, punishment often leads to undesirable emotional side effects sometimes associated with the punisher rather than with the punished behavior. For example, punishment might lead a child to dislike and fear the punisher, and might result in efforts to avoid punishment rather than efforts to avoid the transgressions for which the punishment was administered.
Third, punishment does not present a guide for desirable behavior; instead, it emphasizes unde- sirable behavior.
Finally, some research indicates that punishment sometimes has effects opposite to those intended. For example, Mulvaney and Mebert (2007) found that physical punishment of young children actu- ally increased maladjustment and misbehavior later in life.
Note that most of these objections apply mainly to physical punishment and not to other forms of punishment. These other forms of punishment (verbal reprimands, loss of privileges) have long been considered legitimate and effective means of
controlling behavior. There are instances when punishment appears to be effective in sup- pressing destructive, aggressive, and dangerous behavior in children (and sometimes in adults as well).
Operant Conditioning and Human Behavior Human behavior is seldom as simple as the key pecking of a pigeon or bar pressing of a rat. Still, many of the results of investigations with these animals generalize easily to our behavior. There is no denying the effectiveness of rewards and punishments in our lives. The persistence with which people play slot machines, where reinforcement is on a ran- dom ratio schedule, is one example.
But in some ways, we are quite unlike the caged rat or pigeon. Neither of these animals has much choice: to peck or not to peck; to press or not to press. You, on the other hand, have a stunning array of choices: to study or not to study, to go to a movie, to go to the gym, to text a friend, to listen to music, and on and on. And each of these behaviors might be associated with a very different type and schedule of reinforcement. In short, our lives illustrate what are called concurrent schedules of reinforcement—a variety of options, each linked with different kinds and schedules of possible reinforcement.
Studies of the effects of concurrent schedules on animal behavior typically present the animal with the choice of two behaviors (two levers to press; two keys to peck), each of which is linked to a different type or schedule of reinforcement. In a study of a new
Verbal reprimands and loss of privi- leges are legitimate and effective forms of punishment not subject to the same objections as physical punishment.
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CHAPTER 4Section 4.3 A Transition to Cognitivism
drug treatment for cocaine addiction, for example, rats had a choice of lever A, which would lead to a small dose of intravenously administered cocaine, or lever B, which would provide a highly palatable food as a reinforcer (Thomsen et al., 2008). The rat preferred the drug.
Other studies indicate that, when given choices, rats and pigeons typically match their responses to maximize the likelihood of reward (Herrnstein, 1997). Not surprisingly, stud- ies with humans lead to much the same conclusion. In experimental situations where par- ticipants can choose between different behaviors with different probabilities of reward, they try to maximize the payout (Borrero, Frank, & Hausman, 2009).
4.3 A Transition to Cognitivism
Historically, behavioristic theory has recognized two general classes of behaviors, respon-dent and operant (elicited or emitted) and two general sets of rules and principles to account for each of these. One set relates to classical conditioning; the other, to operant conditioning.
Classical conditioning theory has been found most useful for explaining learning involv- ing autonomic and reflexive reactions, such as those associated with emotional responses, over which we ordinarily have no conscious control.
Operant conditioning had generally been thought to apply to all behaviors that were not respondent—that is, to all behaviors that were not elicited by specific, identifiable stimuli but that simply occurred and could then presumably be brought under the control of reinforcement. Whereas classical conditioning appealed to principles of contiguity, oper- ant conditioning invoked the law of effect: The consequences of behavior determine the probability of future occurrence or of change.
Problems for Traditional Behaviorism
Early behaviorists had hoped to discover laws of learning that would prove sufficiently gen- eral to explain most human behaviors. Unfortunately, behavior did not prove to be as sim- ple as behavioristic theory might have indicated. Even animals sometimes behave in ways that are troublesome for traditional conceptions of behaviorism. In Chapter 2, for example, we described how the Brelands, two of Skinner’s students, trained some 6,000 animals to perform a bunch of stunning animal tricks. But then many of these animals began to “mis- behave,” reverting to their more natural inclinations—a phenomenon called instinctive drift.
Instinctive drift presents a problem for traditional operant theory. It is now apparent that not all behaviors can be conditioned and maintained by schedules of reinforcement, that there is some degree of competition between unlearned, biologically based tendencies and the conditioning of related behaviors.
There are other examples of what are labeled biological constraints that have a clear effect on what an organism learns. Behaviors that are highly probable and relatively easy are typi- cally those that have high adaptive value. Among humans, these might include behaviors
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CHAPTER 4Section 4.3 A Transition to Cognitivism
such as avoiding bitter-tasting substances so that we don’t poison ourselves, or learning a language so we can communicate. Among animals, behaviors such as pecking in birds and nosing around levers in rats are examples of highly probable, biologically based learning.
As we noted in Chapter 2, organisms are prepared to learn certain things and contraprepared to learn others. Thus, it is almost impossible to teach a rat to depress a lever to escape an electric shock (Bolles, 1970). A rat’s natural response to danger is to fight, flee, freeze, or become frantic; it is not to approach a lever and depress it. Therefore, a rat can be trained to jump to escape shock. The ease with which this is accomplished demonstrates pre- paredness. That the rat cannot be trained to depress a lever to escape a shock illustrates contrapreparedness. As Guthrie (1935) put it, “We cannot teach cows to retrieve a stick because this is one of the things that cows do not do” (p. 45).
Insight
Bertrand Russell (1927) made the interesting observation that U.S. and German rats must be quite different. “Animals studied by Americans rush about frantically, with an incred- ible display of hustle and pep, and at last achieve the desired result by chance,” he wrote, adding, “Animals observed by Germans sit still and think, and at last evolve the solution out of their inner consciousness” (p. 33).
He was referring to the fact that U.S. psychology was then largely dominated by the behavioristic notion that responses are learned as a result of the reinforcement of a “cor- rect” response that occurs through trial and error (that is, by chance). At the same time, some German psychologists were working on different parts of the human puzzle.
One of these psychologists, Wolfgang Köhler, spent four years in the Canary Islands dur- ing World War I trying to frustrate apes with a pair of problems: the “stick” problem and the “box” problem. Both problems are essentially the same; only the solutions differ. In both, an ape finds itself unable to reach a tantalizing piece of fruit, either because it is too high or because it is outside the cage beyond reach. In the “stick” problem, the solution involves inserting a small stick inside a larger one to reach the fruit. In the “box” problem, the ape has to place boxes one on top of the other (Figure 4.11).
The solution, insists Köhler (1927), does not involve trial and error, although some of that type of behavior might be displayed in the early stages. When the ape realizes that none of its customary behaviors is likely to obtain the bananas, it may sit for a while, apparently pondering the problem. And then, bingo, it leaps up, quickly joins the sticks or piles the boxes, and reaches for the prize.
That, according to Köhler, is insight, the sudden recognition of relationships among ele- ments of a problem. It is a complex, largely unconscious process, not easily amenable to scientific examination.
The behaviorists were hard-pressed to explain the behavior of Köhler’s apes. Many were tempted to assume that the apes simply tried a number of apelike actions, eventually resorting to combinations of these when none of the simple behaviors was rewarded. Staunch behaviorists would assume that the ape’s recognition of the solution would not occur until the fruit was in hand.
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CHAPTER 4Section 4.3 A Transition to Cognitivism
Many psychologists, however, were reluctant to accept behavioristic explanations for insight, a phenomenon that is common enough among our species that its existence is dif- ficult to deny. And in time, the lowly rat was allowed to contribute in a small way to the study of insight.
In a pioneering study, Tolman and Honzik (1930) allowed a rat to become totally familiar with a maze in which there were several routes to the goal. Once the rat has learned the maze, barriers were placed so that the rat had to choose one of the alternatives. Typically, a rat will always select the shortest route—and the next shortest if that one is later blocked. The behaviorist assumption is that the rats developed a preference for the shortest routes as a result of receiving reinforcement more quickly when they follow these routes than when they stupidly meander through lengthy detours.
The maze, shown in Figure 4.12, has three alternatives. Path 1 is the most direct and is almost invariably chosen when there are no barriers. When there is a barrier at A, the rat would be expected to choose alternative 2. This is, in fact, the case some 93 percent of the time. When the barrier is at B, rats might again be expected to select path 2 since its opening is not blocked. They don’t. These clever rats now run all the way around path 3, despite the fact that they should still have a higher preference for path 2. One explanation is simply that they have developed a cognitive map—a mental representation—of the entire maze, and that they understand that a barrier at B also blocks route 2.
Other studies have shown that a rat will learn a maze even without any tangible reinforce- ment. Rats who are allowed to explore a maze without food learn the maze considerably more quickly than naive rats when food is later introduced. Such observations indicate that rats, too, have some understanding of their environments that goes beyond the for- mation of simple associations among stimuli, responses, and rewards.
Figure 4.11
In the box problems, the chimp piles boxes to reach some fruit—a process involving insight, claimed Köhler. Playing chess, too, requires insight.
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CHAPTER 4Section 4.4 Cognitive Approaches
And we humans, too, form cognitive maps that allow us to navigate in our environment. In doing so, report Foo, Warren, Duchon, and Tarr (2005), we tend to rely heavily on our recollection of landmarks and their positions relative to each other and to our preferred paths. Forming mental representations of our worlds is a uniquely cognitive activity.
4.4 Cognitive Approaches
Instinctive drift, delayed taste aversion, cognitive maps, and insightful learning pre-sent serious problems for traditional behavioristic theories. And if behaviorism does not explain the simpler behaviors of animals, then the presumably more complex behaviors of humans might be even less well explained. If even animals have concepts and apparent thought processes, psychology should perhaps concern itself with these as well as with more easily observed and described behaviors.
Enter cognitivism, an approach concerned mainly with intellectual events such as prob- lem solving, information processing, thinking, and imagining. It is an approach that has sometimes rejected behaviorism as overly mechanistic and incomplete. Behaviorism does not deal well with thinking—with cognition. For that, we need other approaches.
Food
Block B
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Path 3
Path 2
Start Figure 4.12
In the Tolman and Honzik (1930) blocked-path study, rats that had learned this maze almost invariably selected path 3 when path 1 was blocked at B. It seemed they somehow knew that the barrier at B also blocked the much shorter path 2.
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CHAPTER 4Section 4.4 Cognitive Approaches
The Main Beliefs of Cognitive Psychology
The dominant metaphor in cognitive psychology, notes Garnham (2009), is a computer- based, information processing (IP) metaphor. The emphasis is on the processes that allow the perceiver to perceive, that determine how the actor acts, and that underlie thinking, remembering, solving problems, and so on. Not surprisingly, experimental participants in cognitive research tend to be human rather than nonhuman.
Learning Involves Mental Representation Cognitive approaches to learning presuppose mental representation and information pro- cessing. The behaviorist view, as we saw, tends to describe learning as a largely uncon- scious process where factors such as repetition, contiguity, and reinforcement push the organism this way and that. In contrast, the cognitive view describes an organism that is more thoughtful, that can mentally imagine and anticipate the consequences of behavior. In this view, the learner is not a passive receiver of information, pushed and prodded by stimuli and their consequences. Instead, the learner actively participates in the learning process, discovering, organizing, and using strategies to maximize learning and reward.
Learners Are Not Identical Behaviorism sees all learners as relatively equal in terms of their susceptibility to the effects of reward and punishment. In contrast, cognitivism emphasizes that learners are different. Individuals come with different background information, different inclinations and motives, different genetic characteristics, and different cultural origins. As a result, even in the same situation, they often learn very different things.
New Learning Builds on Previous Learning The importance of individual difference among learners rests partly on the fact that new learning is often highly dependent upon previously acquired knowledge and skills. Take a hundred naive rats, and most of them can easily be conditioned to depress a small lever. But take a hundred 15-year-olds, and perhaps only a handful will be ready to understand the mysteries of quantum theory.
As we see in later chapters, for most important topics in human psychology (such as mem- ory, motivation, and social learning), the continuing search for pieces of the puzzle has taken a largely cognitive turn.
Bandura’s Social Cognitive Theory
You cannot, in any simple sense, condition someone to learn quantum physics. Still, explains Albert Bandura (1997), we learn many things through conditioning. It is clear that we are highly responsive to reinforcement—and perhaps to punishment as well. What is not so clear in most accounts of human learning through operant conditioning is just how oper- ants come about in the first place.
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CHAPTER 4Section 4.4 Cognitive Approaches
Bar pressing and key pecking are simple behav- iors that are highly likely to occur in a given situ- ation. A complex human behavior such as driving a car is not likely to appear fully formed, ready to be reinforced. And shaping such a complex behav- ior by reinforcing behaviors that slowly approxi- mate the complete sequence of required behaviors would be a highly ineffective way of learning.
Nor do we learn complex behaviors such as how to drive a car through trial and error. We learn many of these complex behaviors, explains Bandura, through observational learning—that is, by observ- ing and imitating models. And, in a sense, learning through imitation is a form of operant learning in that the imitative behavior is like an operant that is learned as a result of being reinforced.
A large number of studies indicate that social imi- tation is a powerful teacher among humans: Even children as young as 2 or 3 imitate and learn from each other. Moreover, a number of investigations show that monkeys, dogs, birds, and dolphins can
learn a variety of relatively complex behaviors by observing their trained fellow-animals (Ferrari et al., 2009; Miller, Rayburn-Reeves, & Zentall, 2009).
Models In Bandura’s social cognitive theory, models are not limited to people who might be imitated by others; they include symbolic models as well. Symbolic models are any rep- resentation or pattern that can copied, such as oral or written instructions, pictures, book characters, mental images, cartoon or film characters, and television actors.
Models provide the imitator with two kinds of information: how to perform an act, and what the likely consequences of doing so are. And if the observer now imitates the behav- ior, there is a possibility of two different kinds of reinforcement. One, direct reinforce- ment, results from the consequences of the act itself. If 10-month-old Norbert is given a glass of milk when, in trying to imitate his sister, he says, “mwuff,” he may soon learn to say “mwuff” whenever he is thirsty.
The other source of reinforcement is secondhand, labeled vicarious reinforcement. When you see someone doing something repeatedly, you unconsciously assume that the behav- ior must be reinforcing for that person. You might now imitate this behavior and continue to produce it even in the absence of any direct reinforcement.
Reciprocal Determinism There is little doubt that we engage in many behaviors because of the reinforcing con- sequences of so doing. But reinforcement does not control us blindly, explains Bandura
Imitation is a powerful teacher among children. And sometimes among ani- mals too.
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CHAPTER 4Section 4.4 Cognitive Approaches
(1997); its effects depend largely on our awareness of the relationship between our behav- ior and its outcomes. What is fundamentally important is our ability to figure out cause- and-effect relationships and to anticipate the outcomes of our behaviors.
Not only can we anticipate and imagine the consequences of our behavior and therefore govern ourselves accordingly, but we can also deliberately select and arrange our envi- ronments. That we are both products and producers of our environment is the basis of Bandura’s concept of triadic reciprocal determinism.
In this view, there are three principal features of our social cognitive realities: our personal factors (our personalities; our intentions; what we know and feel); our actions (our actual behaviors), and our environments (both the social and physical aspects of our world). These three factors affect each other reciprocally. For example, a harsh, demanding envi- ronment might alter Joe’s personality, making him bitter and cynical. This might change his behavior, driving him to more selfish acts. These actions might destroy friendships, thus changing important aspects of his social environment. And the changing social envi- ronment, in turn, might further affect his personality and his behavior.
On the other hand, instead of making him bitter and cynical, a tough environment might lead Joe to rally his friends that they might struggle together to ease their lot. The recip- rocal influence of person, action, and environment might be no less in this case, but the outcomes might be vastly different (Figure 4.13).
The social and physical environment as experienced
by the individual The person’s behavior
Personal factors like biology (gender; hormones), affect (emotions; moods), and cognition (knowledge, goals, expectations)
Figure 4.13
Bandura’s notion of triadic reciprocal determinism. Behavior, the person, and the environment all mutually influence and change each other.
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CHAPTER 4Section 4.4 Cognitive Approaches
Effects of Imitation Through observational learning, we learn three different classes of behaviors, explain Bandura and Walters (1963): We learn brand new behaviors (modeling effect); we learn to suppress or stop suppressing deviant behaviors (inhibitory/disinhibitory effect); and we learn to engage in behaviors similar but not identical to the model’s behavior (eliciting effect) (Table 4.1).
Table 4.1 Three Effects of Imitation: Bandura’s Theory
Type of Effect Description Illustration
Modeling Effect Acquiring a new behavior as a result of observing a model.
After watching a mixed martial arts program, Jenna tries out a few novel moves on her young brother, Liam.
Inhibitory-Disinhibitory Effect
Stopping or starting some deviant behavior after seeing a model punished or rewarded for similar behavior.
After watching Jenna, Nora, who already knew all of Jenna’s moves but hadn’t used them in a long time, now tries a few of them on her sister (disinhibitory effect). Nora abandons her pummeling of her sister when Liam’s mother responds to his wailing and takes Jenna’s smartphone away (inhibi- tory effect).
Eliciting Effect Engaging in behavior related to that of a model.
Robin tries to learn to play the guitar after her cousin is applauded for singing at the family reunion.
Humans as Agents of Their Own Behaviors Some of our behaviors, such as our classically conditioned fears, are under the control of stimuli. Others, like our highly reinforced imitations, are controlled more by their con- sequences. And a third group of behaviors are controlled by cognitive activities such as thinking and imagining. Bandura labels these three behavior control systems stimulus con- trol, outcome control, and symbolic control.
In the end, although stimuli and outcomes might affect our behaviors, it is the symbolic control system that is most important in Bandura’s description. We are not simply pawns pushed hither and yon by rewards and punishments and classically conditioned reflexes. We are in charge, Bandura (2001) insists: We are agents of our own actions.
Being agents of our own actions requires three things: First, it requires intentionality. If someone bumps into you, causing you to spill your latte on your friend, you would not be considered an agent of that action. But if you deliberately threw your coffee at said friend, you would be the agent of that action.
Second, intentionality implies forethought. It is the ability to symbolize that allows you to foresee the consequences of the actions you intend. You could not intend to amuse your friend with your behavior unless you could foresee the effects of tossing your coffee.
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CHAPTER 4Section 4.5 Practical Applications of Learning Principles
Finally, being agents of our actions implies being able to reflect on them and to reflect on ourselves and especially on our own effectiveness—on our self-efficacy. Self-efficacy, as we see in Chapter 6, is a very important concept in human motivation. Our estimates of our personal effectiveness, of our likelihood of success, have a lot to do with what we choose to do and how much effort we are willing to expend doing it.
4.5 Practical Applications of Learning Principles
There are countless, everyday, intuitive applications of classical and operant condition-ing principles and of Bandura’s social-cognitive theory. People are controlled and manipulated by organizations and by other people, sometimes quite unconsciously— although often consciously as well. Performers’ behaviors are shaped by the responses of their audience; the behavior of teachers is shaped by the responses of their students; consumers’ behaviors are affected by advertising media; models are used to influence consumers; drug addicts are reinforced by the effects of the drugs they take. Even crimi- nals are reinforced by the outcomes of their behaviors.
Applications of Behaviorism
Findings in behaviorism have led to the development of a variety of practical applications in fields such as education and psychotherapy. For example, many teachers use system- atic reinforcement programs to foster learning or to prevent or correct deviant behavior.
General instructional recommendations that derive from conditioning principles suggest that teachers should:
• Try to maximize pleasant unconditioned stimuli in their classrooms. This might involve making sure learners are comfortable, that surroundings are colorful and upbeat, and that no individual is faced with overwhelming demands. At the same time, teachers need to minimize the unpleasant aspects of being a student to reduce the number and potency of negative unconditioned stimuli in the classroom.
• Use punishment—especially corporal punishment—sparingly as it is not very effective for eliminating undesirable behavior and even less effective for teaching desirable behavior.
• Be aware of what is being paired with what in the classroom, so as not to inadver- tently condition undesirable behaviors. If the teacher smiles when Johnny does something outrageous—or if his classmates all laugh—doing outrageous things may well be what Johnny learns.
• Limit the use of repetition without reinforcement; it does little to improve learning. • Emphasize positive rather than aversive methods of control.
The systematic application of learning principles to change behavior is labeled behav- ior modification. Behavior modification is widely used in schools and institutions for children with behavioral and emotional problems, as well as in the treatment of mental
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CHAPTER 4Section 4.5 Practical Applications of Learning Principles
disorders. Essentially, it involves the deliberate and systematic use of reinforcement, and sometimes punishment, to modify behavior.
Two behavior modification techniques are described in Chapter 9. One, systematic desen- sitization, is widely used to treat phobias (intense, debilitating fears). Basically, it involves conditioning a relaxation response that conflicts with the fear responses characteristic of phobias. The other, aversive conditioning, is sometimes used to treat drug or alcohol addic- tion. It attempts to attach negative, avoidance, responses to the use of these substances, perhaps by using stimuli such as electric shock or nausea-inducing drugs.
Applications of Cognitivism
Cognitivism typically views the learner as an active, information processing being, capable of imagining and anticipating the consequences of behavior, and essentially responsible for its own actions as well as for constructing its own view of the world. This orienta- tion lends itself especially well to discovery learning. This is a learner-centered approach where content is not organized by the teacher and presented in a relatively final form. Instead, learners are expected to investigate and discover for themselves, and to construct their own mental representations—hence the current expression for discovery and other related approaches, widely used in educational circles: constructivism.
A cognitive view of the learner also supports approaches designed not so much to teach students specific content, but more to teach them how to learn—to make self-regulated learners of them. To this end, cognitively oriented educational psychologists suggest that teachers should develop problem-solving skills in students—for example, by giving them practice with the five-step strategy for general problem solving suggested by Bransford and Stein (1993). The five steps are easily remembered with the acronym IDEAL:
Identify problems and opportunities
Define goals and represent the problem
Explore possible strategies
Anticipate outcomes and act
Look back and learn
There are a wide variety of specific cognitively based approaches to teaching, including reciprocal teaching, a method designed to improve reading comprehension, and cogni- tive apprenticeship, where novice learners are paired with older learners, teachers, or parents who serve as mentors and guides. There are also various programs designed to develop cognitive strategies, as well as to help learners become aware of their own use of cognitive strategies, to reflect on them, to evaluate their effectiveness, and to change them as needed.
We are all players of what Flavell (1985) calls the game of cognition. It is a strategic game—a game for which we need to have mastered the strategies that allow us to understand and make sense of information, to organize it and process it, to recall it when we need it, and to use it in the best way possible. Most of us learn cognitive strategies incidentally in the
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CHAPTER 4Main Points
course of learning other things. Now cognitive psychology suggests there should be con- certed attempts to make sure all learners develop the best cognitive strategies possible.
Some people play the game of cognition very badly.
Some play it extraordinarily well.
Main Points 1. What Is Learning? Learning is a relatively permanent change in behavior result-
ing from experience but not including the effects of fatigue, maturation, drugs, injury, or disease.
2. Behavioristic Approaches: Classical conditioning (Pavlov) describes learning through stimulus substitution as a result of repeated pairings of an uncondi- tioned with a conditioned stimulus. Operant conditioning (Skinner) describes changes in the probability of a response as a function of its consequences.
3. A Transition to Cognitivism: Phenomena such as blocking, instinctive drift, delayed taste-aversion, and insightful learning present problems for behavioristic explana- tions, but less for cognitive explanations.
4. Cognitive Approaches: Cognitive psychology describes a self-aware individual, able to anticipate the consequences of behavior and guide actions accordingly. Bandura’s social cognitive theory explains how we learn by imitating (observa- tional learning), how we shape our environments even as they shape us (triadic reciprocal determinism), and how we are agents of our own actions.
5. Practical Applications of Learning Principles: Behavioristic approaches to learning underscore the importance of maximizing positive stimuli and minimiz- ing the more negative. They suggest ways of using reinforcement and punish- ment for instruction as well as in behavior modification programs. Cognitive approaches encourage learner-centered approaches to instruction (discovery learning, reciprocal teaching, teaching problem solving, and helping learners develop cognitive strategies).
Study Terms
behavior modification
behavioristic theories
blocking
classical conditioning
cognitive apprenticeship
cognitive theories
cognitivism
concurrent schedules of reinforcement
conditioned response (CR)
conditioned stimulus (CS)
constructivism
contiguity
direct reinforcement
discovery learning
discriminative stimuli (SD)
eliciting effect
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CHAPTER 4Main Points
extinction
extrinsic reinforcement
imitation
inhibitory/disinhibitory effect
insight
instincts
intrinsic reinforcement
law of effect
learning
modeling effect
models
negative reinforcer
observational learning
operant conditioning
operants
positive reinforcer
primary reinforcers
reciprocal teaching
reflexes
reinforcement
reinforcer
respondent
responses
secondary reinforcers
self-efficacy
shaping
Skinner box
social cognitive theory
stimuli
stimulus discrimination
stimulus generalization
symbolic models
triadic reciprocal determinism
unconditioned response (UR)
unconditioned stimulus (US)
vicarious reinforcement
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5
Memory and Intelligence
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • What is the modal model of memory? • What are the key differences between sensory, short-term, and long-term memory? • What is Baddeley’s model of working memory? • What are some important processes in long-term memory? • How can forgetting be explained? • What are some important techniques for improving memory? • Which common beliefs about IQ are mythical? • How can intelligence be defined and measured? • What determines intelligence?
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CHAPTER 5Memory and Intelligence
Vague memories hang about the mind
like cobwebs. —George Eliot, Romola
Chapter Outline
5.1 What Is Memory? The Filing-Cabinet Analogy
5.2 Stages of Memory Sensory Memory Short-Term Memory Long-Term Memory Physiology of Memory Processes in Long-Term Memory
5.3 Forgetting Fading Theory Repression Distortion Theory Interference Theory Retrieval-Cue Failure
5.4 Improving Memory Mnemonic Aids
5.5 What Is Intelligence? Myths about IQ Views of Intelligence
5.6 Measuring Intelligence The IQ IQ Tests Misuses and Abuses of Tests
5.7 Influences on Intelligence Heredity and Environment
But there is only a hint of cobwebs when you first awaken in the early morning: They disappear almost before you notice. And your memories don’t seem especially vague. Without wondering about it, you know at once that it is early morning, that it is time to get up. Nothing surprises you about the bed in which you find yourself; you recognize the painting on the wall; you understand the meaning of the digits on the clock; you know the shoes by the bed are yours; you don’t wonder where the bathroom is. Or the refrigerator. You know who else is in the house and where they are.
And as you go through your morning ritual, the events of the coming day unfold like a condensed preview in your mind’s calendar: When you have washed and eaten, you will bicycle to school and go into the humanities building for your first class. Later you’ll finish your assignment. After that . . .
Now the cat rubs hard against your leg, interrupting your thoughts. But you are neither startled nor surprised nor puzzled by the cat or by anything else that you have experienced this sparkling new morning.
Why?
Because everything is familiar: Because you have these many things in your memory.
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CHAPTER 5Section 5.1 What Is Memory?
5.1 What Is Memory?
Most of you know who you are during every waking moment of your life (provided it is not too terribly clouded by alcohol, drugs, fatigue, or illness). You take this knowl- edge almost entirely for granted. There is no need for you to look into your wallet when you first awaken in the morning to rediscover your identity in cold print corroborated by a photo. The information is already in your memory.
You understand the meaning of this sentence. You take that understanding for granted as well, never realizing that all sentences would be absolutely meaningless if you did not remember their beginnings once you reach their ends.
July 4, December 25, Leonardo da Vinci, Sammy Davis Jr., and a variety of other dates and names may have meaning for you. But there is no meaning implicit in the names or dates themselves; these are only light waves or molecular disturbances in the air. The meanings are in your memory.
Memory is involved in all aspects of human functioning. In fact, it is very difficult to sepa- rate memory and learning, so closely are they linked. Learning is a change in behavior that results from experience; and, in a sense, memory is the effect of experience. More precisely, it is the system that allows us to retain and retrieve the effects of experience. There will be no evidence of learning without something having happened in memory; by the same token,
something happening in memory implies learning.
We often speak as though a memory were a thing that people have—a thing that varies from one individual to another in terms of how well it func- tions. In fact, however, we have no single standard by which to judge this “thing.” If I say that I have a good memory, as anybody might from time to time, I might mean any number of things—other than that my recollections are pleasant or unpleas- ant. Perhaps I have just remembered a date or a name. Alternatively, I might have obtained a high score on some measure of achievement. My good memory might also refer to the fact that I have been successful in recalling a poem that I intended to memorize. Then again, it might refer to the fact that I can read a chapter and recall its meaning, or that I can recall some of its sentences and perhaps some of the pages on which specific information can be found. That I have a good memory might also refer to the fact that I have just discovered myself capable of something I have not done for many years.
In contrast to a good memory, a bad memory may be seen as one that is sometimes incapable of some of the activities just described. Good and
That we know who we are depends entirely on our memory. Unless we have lost that part of our memory, the big question mark has to do with other things.
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CHAPTER 5Section 5.2 Stages of Memory
bad memories, however, are not the simple mani- festation of some inherited ability. Remembering is related to factors such as learning, the organi- zation of material, motivation, and intact neural structures.
The Filing-Cabinet Analogy
Human memory has frequently been compared to a filing cabinet. It is apparently a huge, limit- less, grayish cabinet into which we can toss a great variety of material that is thus kept out of the way until we have some use for it.
Several related processes are involved in the fil- ing operation. Much as a clerk must first record material if it is to be filed, so it is necessary for us to somehow encode (transform information into a storable form) before we can remember. If the material is not very important and is not likely to be necessary very often, if ever, again, there is little point in cluttering the files with it. Better to leave it on the desk for a short while, use it, and throw it in the wastebasket. We have a system very much like that, which is extremely useful in ensuring that we do not clutter our cabinets.
We look at our computer screens or smartphones for telephone numbers, use them, and promptly forget them. But if the material is important, we file it in our memories so that we can later retrieve it.
The three Rs of filing—recording, retaining, and retrieving—are analogous to the three processes involved in remembering: encoding, storing, and retrieving. How do we make memories? Can everything that is stored be retrieved? Why are some things remembered forever and others forgotten almost immediately?
5.2 Stages of Memory
Answers to these questions are implicit in the most popular current description of human memory, which takes the form of what is labeled the modal model of mem- ory (here modal simply means widely accepted). It is a small but important piece of the human puzzle.
The model makes important distinctions among sensory memory, short-term memory (STM), and long-term memory (LTM). The main differences between these three stages of memory have to do with (a) the amount of information each can hold, (b) how long they
Imperfect though they might be, our memory systems are sometimes aston- ishingly effective. Memory has been compared to a filing cabinet that allows us to record, retain, and retrieve.
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CHAPTER 5Section 5.2 Stages of Memory
can hold material in storage, and (c) their most important functions. The modal model is summarized in Figure 5.1.
Sensory Memory
If, as you are reading a book, your smart phone rings, you answer, and someone says, “Hi. So tell me, what page are you on?” Chances are you won’t immediately know. Yet your vision probably glanced across the page number, perhaps even more than once. But the fact is that you were never really aware of the number. It was simply a fleeting impression in what is called sensory memory.
Sensory memory is a term for the immediate, fleeting effect of stimuli. As we saw in Chap- ter 3, the cocktail party phenomenon illustrates that stimulation to which we are not attend- ing nevertheless continues to be available for a fraction of a second—almost like an echo. In fact, Neisser (1976) labeled it echoic memory (for auditory stimulation) and iconic memory (for visual stimulation). In order to be aware of the stimulus, you need to pay attention to
Impression or
sensation
Sensory Memory
Words, names,
numbers, sensations maintained by rehearsal
Short-Term Memory
Concepts, meaning
Long-Term Memory
S E
N S
O R
Y IN
P U
T
Forgotten almost
immediately
Forgotten within
moments
Recalled indefinitely
Attention
Encoding
Retrieval
F or
ge tti
ng
F or
ge tti
ng
R et
rie va
l
Figure 5.1
The modal model of memory: a storage model. Note that these three components of memory do not refer to three different locations in the brain or other parts of the nervous system but, rather, to how we classify memory storage.
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CHAPTER 5Section 5.2 Stages of Memory
it. And whether or not you attend to it depends on your interests, your motivation, and certain characteristics of the stimulus that grab your attention—for example, someone shouting some word very loudly, or asking you what page you are on.
Short-Term Memory
If someone did ask you what page you are on, you would pay attention and become con- scious of it. One way of looking at sensory memory is to say that it precedes attention— that it occurs without your awareness. When you become aware of a stimulus, it passes into short-term memory. Whereas sensory memory lasts only milliseconds, short-term memory lasts seconds—but not hours or even minutes. Short-term memory describes items of which you are immediately conscious but that will no longer be recallable the moment you stop rehearsing them.
Short-term memory is what makes it possible for you to look at a phone number, look away and dial the number, and promptly forget the whole thing. It is also the kind of memory that allows you to remember the first words in this sentence so that by the time you get to the end, it might make sense to you.
Studying Short-Term Memory One of the problems in investigating memory is that it is difficult to control for previ- ous learning. If participants have already learned what the experimenter wants to teach them, resulting measures will be of long-term rather than short-term memory. One way of controlling for this possibility is to use nonsense syllables, meaningless arrangements of letters such as gur, kar, lev, zib, tel, and cez.
Beginning with the work of Ebbinghaus (1885/1964), who pioneered their use, thousands of experiments have been conducted with nonsense syllables. Some require simply that the subject remember as many words as possible after learning (free recall); others pre- sent nonsense syllables paired with meaningful words (paired associate learning) and later require subjects to recall the syllable when given the meaningful word (cued recall). Still others present series of nonsense syllables and require subjects to recall words in their correct order (serial recall).
Characteristics of Short-Term Recall One of the important characteristics of short-term recall is that it is, in fact, short term. Its content, which describes our immediate awareness, lasts only moments before we turn our attention to something else.
A second important characteristic of short-term memory is that it is highly limited in capacity. Immediate recall of short lists of nonsense syllables (seven or fewer) presented at a rate of one per second is usually close to 100 percent (Peterson & Peterson, 1959). When given longer lists, subjects remember only a few, haphazardly. This observation has led to the widely held belief that the short-term memory span is limited to seven items (G. A. Miller, 1956). For some individuals, it is lower than that; others can recall more than
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CHAPTER 5Section 5.2 Stages of Memory
seven items. But all the average person can hold in conscious awareness at one time is seven items.
The very short duration of short-term memory, coupled with its highly limited capacity, is one of the reasons why it is often difficult to do two things at once. If one activity requires your atten- tion, there is not likely to be a lot of memory space left for the other activity—such as texting and talking on the phone simultaneously.
There is a way around the limited capacity of short-term memory, says Miller (1956), because the items that fill each of the seven “memory slots” do not have to be a single unit. Instead, they might be composed of several units—a chunk- ing of items, so to speak. Chunking, in memory, involves organizing items into larger units—like letters being organized into words and words into meaningful sentences. The term chunking was introduced in a paper on memory by Miller (1956) in which he uses an analogy to describe memory. In some ways, he explains, memory is like a change purse that can only hold seven coins. If it contains seven pennies, it will be full. But it could just as well contain seven quarters. Or even seven golden coins.
What Happens in Short-Term Memory: Baddeley’s Model Short-term memory describes immediate awareness or attention. It is the memory stage that allows us to keep information in mind long enough to make sense of sequences of words, to solve problems, to make decisions, or to do mundane things such as dial tele- phone numbers or tune our radios while we drive.
Short-term memory must involve some sort of mental activity that makes these things pos- sible, argues Baddeley (Baddeley, 2007; Baddeley & Hitch, 1974): hence his model of working memory, a model that describes three related systems that account for the workings of STM.
First, Baddeley explains, there must be some sort of controlling process or system over- seeing the entire process. He labels this system the central executive system. Its main function is to regulate the flow of information from sensory storage (that is, to bring infor- mation into conscious attention). It also processes information for longer-term storage and retrieves information from long-term memory. In brief, it supervises and controls our ongoing, conscious cognitive processing.
The model suggests that there must also be at least two other systems to maintain ver- bal and visual/spatial information so that it is available to working memory. These are called slave systems because they do the bidding of the central executive system. The two slave systems are the phonological loop and the visual-spatial sketch pad. The phono- logical loop maintains verbal information, such as words or numbers, and is important in
Short-term memory is a little like a change purse, says Miller. But it can only hold seven or so items. Some, like gold coins, represent bigger “chunks” than would pennies.
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CHAPTER 5Section 5.2 Stages of Memory
learning things such as new words. Similarly, the visual-spatial sketch pad is concerned with processing material that is primarily visual or spatial (Figure 5.2).
Long-Term Memory
All our relatively stable information about the world—what we can remember but is not in our immediate consciousness—makes up our long-term memory (LTM). As we saw, what is in our immediate consciousness defines STM, which is an active, ongoing, con- scious process; LTM is a more passive, unconscious process (Figure 5.3).
Slave Systems (maintain information so that it remains available
to working memory)
Central Executive System
Phonological Loop (maintains verbal
material like words and numbers)
Visual-Spacial Sketch Pad
(maintains material that is primarily visual)
Supervizes activity of all other systems
Controls flow of information from
sensory storage and from long-term memory
Processes material kept temporarily available by
slave systems for storage in long-term memory
Figure 5.2
A representation of Baddeley’s model of working memory. Information that we remember must first be sensed and then must somehow be held on to and processed if it is to be trans- ferred to long-term memory. Baddeley’s model describes how memory works. The central executive system controls the flow of information from sensory storage and from long-term memory and processes it for long-term storage. The slave systems maintain information so that it is available for processing.
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CHAPTER 5Section 5.2 Stages of Memory
Long-Term Memory Is Relatively Stable Because STM is an active, conscious process, limited in both duration and capacity, it is easily disrupted by external events, as is clear every time we become distracted. LTM, on the other hand, is not easily disrupted. If you remember the capital of Denmark today, you are still likely to know it next month, next year, maybe even next decade (Magnussen, Greenlee, Aslaken, & Kildebo, 2003).
Some memories are astonishingly resistant to the passage of time. Olfaction is a case in point (Poncelet et al., 2010). In one study, Goldman and Seamon (1992) identified and bottled seven odors associated with early childhood (for example, crayon shavings, Play- Doh, bubble soap) and another seven more recently experienced in adulthood (chocolate, popcorn, cigarette tobacco). Adults could correctly identify about 90 percent of the more recent odors and an impressive 75 percent of the childhood odors.
Less than 1 second
Fleeting
Limited
Momentary, unconscious impression; a
passing sensation or association
Sensory Memory
Temporary, less than 20
seconds Duration
Stability
Capacity
General Characteristics
Easily disrupted
Limited (7± 2 items)
Immediate conciousness;
active; maintained
by rehearsal
Short-Term Memory
Indefinite
Not easily disrupted
Unlimited
All our knowledge; passive; the
result of encoding and
storage of information
Long-Term Memory
Figure 5.3
A comparison of short-term and long-term memory.
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CHAPTER 5Section 5.2 Stages of Memory
Long-Term Memory Is Constructive Although long-term memory tends to be highly stable, what is recalled is not always what was perceived or learned in the first place. For example, Johnson, Bransford, and Solomon showed subjects these two sentences (1973, p. 203):
John was trying to fix the birdhouse. He was pounding the nail when his father came out to watch him and to help him do the work.
Later, the same subjects were again shown the two sentences along with several others, one of which was the following:
John was using the hammer to fix the birdhouse when his father came out to watch him and to help him do the work.
Most subjects were more convinced that they had seen this last sentence rather than either of the sentences they had actually seen. Why? Because, explain Johnson and associates, although the word hammer had never been presented, subjects recalled the meaning of the sentences. Knowing that hammers are used to pound nails, they generated the word into their recollections.
That memory tends to be highly generative has important implications in judicial systems that tend to rely heavily on human testimony. As we see in a later section on repression and false memories, research indicates that under a variety of circumstances, witnesses can be expected to remember incorrectly or to remember events that have not even occurred (Laney & Loftus, 2010).
Understanding and Emotion Influence Memory Subjects in the birdhouse construction study who mistakenly thought they remembered a sentence with the word hammer in it illustrate how understanding can affect memory. If the subjects had not known what a hammer was, even if it had actually been in the sen- tence they might not have remembered seeing it. The point is that meaningful material is more easily remembered than material that is confusing and unclear.
Particularly striking and highly emotional events can also be extraordinarily memorable. Many of these give rise to flashbulb memories—apparently exceptionally vivid, detailed, and accurate recollections of a single event. These are often mass occurrences, as hap- pened with the assassination of President Kennedy and the death of Princess Diana, or the events of September 11. They might also be more personal, as might happen when you discover that you’ve won an enormous lottery or that someone close to you has been in an accident.
Flashbulb memories are typically marked by the impression that we remember with exceptional detail and accuracy where we were when we heard the news, what we were doing, how we felt, what happened next, and so on. However, most research indicates that flashbulb memories are not especially accurate. For example, Wolters and Goudsmit (2005) report that university students’ recollections of the September 11 attacks became progressively more confused and uncertain with the passage of time. Strikingly, however,
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CHAPTER 5Section 5.2 Stages of Memory
students remained absolutely convinced that they remembered accurately.
Rehearsal and Intention Influence Long-Term Memory Less striking but frequently rehearsed items may also be recalled for a long time. Such might be the case for your driver’s license number, your Social Security number, or your current telephone num- ber. Interestingly, however, even when these are rehearsed countless times, they are soon forgot- ten when they are no longer required. If your tele- phone number has changed recently, you might well be unable to recall your previous number.
Long-term memory is also influenced by motives and intentions. For example, what we remember of what we read depends very much on the purposes for which we read. Reading a novel for enjoyment may be quite different from reading the same novel for English class. In the second case, you modify your strategies. Perhaps you analyze, review, and evaluate so that you can later discuss and generalize your understanding. If your intention were sim- ply to enjoy the rhythm of the language and to find out what happens to the characters, you might struggle mightily when you are later asked to generalize.
Two Kinds of Long-Term Memory: Explicit and Implicit When a hungry psychologist asked a centipede to explain how it managed to walk with so many legs, the poor thing was quite perplexed. You see, it had never really thought about the problem; it just darn well knew how to walk. But now it began to try to understand the process—which leg goes where, when, which one next, trying out various combinations and movements at different speeds, trying to factor in the effects of slopes and winds and slippery surfaces, until, in the end, completely baffled, it had wrapped its poor legs into a huge knot.
Much of our knowledge, too, is like that of the centipede’s knowing how to walk. Can you explain how to ride a bicycle in such a way that a novice, hearing your instructions, can then jump on a bicycle and pedal away? Not likely. Your knowledge of how to ride a bicycle is an implicit memory (also termed nondeclarative memory). It is somehow rep- resented in your muscles and joints and arms and legs in cooperation with your vestibular sense. It cannot easily be verbalized—hence it is implicit or nondeclarative. Implicit memory is what allows you to pull out your driver and smack a golf ball consistently between 300 and 320 yards. You wish.
But you do have many memories about which you can speak, memories that you can make explicit: hence explicit memory (also called declarative memory). All your knowl- edge about the world and your recollections of personal experiences are examples of declarative memory.
Striking, highly emotional events like the death of Princess Diana can give rise to widespread “flashbulb” memo- ries. Although these are marked by the absolute conviction that we remember the event with exceptional detail and accuracy, most flashbulb memories are not especially accurate.
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CHAPTER 5Section 5.2 Stages of Memory
The distinction between implicit and explicit memories has been highlighted in studies of amnesiacs. Many of these people, who have lost huge chunks of their explicit memories (they no longer remember who they are, where they went to school, who their friends are, what they did for a living, where they live) nevertheless retain many implicit memories. They still know how to drive a car, how to ride a bicycle, how to walk, and so on (Keane et al., 1997).
Two Kinds of Explicit Memory: Semantic and Autobiographical A 30-year-old man, known to us only as K. C., missed a curve with his motorcycle, suffering severe brain damage (Tulving, Schacter, McLach- lan, & Moscovitch, 1988). He is now incapable of consciously remembering anything he has ever done, seen, heard, or felt in the past. Yet he knows and can verbalize all sorts of information. “K. C.,” writes Tulving, “knows that his family owns a summer cottage, knows where it is located, and can point out the location on a map of Ontario, and he knows that he has spent summers and weekends there. But he does not remember a single occasion when he was at the cottage or a single event that happened there” (1989, p. 363). K. C. remembers objective facts and procedures well enough that his measured intelligence appears quite normal. Yet he remembers abso- lutely nothing of his personal life.
Cases such as that of K. C. provide clear examples of two distinct kinds of explicit memory: On the one hand, there is stable knowledge about the objective world, knowledge necessary for activi- ties such as speaking a language, doing arithme- tic, or knowing where North America is. That is called semantic memory. K. C.’s semantic mem- ory appears to have remained intact.
On the other hand, there is our personal, autobio- graphical knowledge about the places we went, the people we saw, the things we did, and the things that happened to us. These memories are typically tied to a time and place. They are our autobio- graphical memories (also sometimes called episodic
This young man cannot easily explain how to ride a bicycle. Nor can I. The memory is implicit. That his sister can explain how to make an exquisite mixed pepper salad reveals an explicit memory.
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CHAPTER 5Section 5.2 Stages of Memory
memory because they are recollections of episodes in our lives). K. C.’s amnesia has wiped out his autobiographical memory (Figure 5.4).
Physiology of Memory
We know that learning and remembering must result in some sort of change in the brain. As we saw in Chapter 2, some early researchers, like Karl Lashley, thought that they might be able to find memory traces (called engrams) by cutting out tiny pieces of a rat’s brain to see
Long-Term Memory
All relatively permanent, lasting effects of
experience.
Declarative Memory
(also called explicit memory)
Potentially conscious, recallable information
Nondeclarative Memory
(also called procedural or implicit memory)
Unconscious, nonverbalizable effects of learning, like motor skills or classically conditioned responses
(Example: Doing a triple somersault)
Semantic Memory
Stable, abstract knowledge that underlies language,
principles, facts, strategies (Example: Knowing that the Pyrenees separate
France and Spain)
Episodic Memory
Personal, autobiographical knowledge; memory of
doing things (Example: Recalling cycling
through Roncesvalles in the rain)
Figure 5.4
A model of long-term memory. Studies of memory failure as well as imaging studies of the brain suggest that different parts of the brain are involved in each type of memory.
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CHAPTER 5Section 5.2 Stages of Memory
if they could cut out an engram. They could not. They were eventually forced to conclude that memories are scattered throughout the brain rather than located in just one place.
Neuroscience Neuroscientists, using modern brain-imaging techniques (discussed in Chapter 2), pro- vide new insights not only into how the brain works, but also into where memories might be stored. For example, when EEG recordings are taken while a person (or an animal) is exposed to a specific stimulus, it is possible to detect electrical activity in the brain that is directly related to that stimulus. That activity is called an event-related potential (ERP). And using magnetoencephalography, it is possible to measure changes in the magnetic field that result from the flow of electrical currents among nerve cells. These event-related fields (ERFs) are detectable even though they involve magnetic fields less than one bil- lionth as strong as the earth’s magnetic field (Yamagishi, 2008).
Studies of ERPs and ERFs often present subjects with auditory stimuli such as words or tones. It is then possible to detect precise neural activity corresponding to perception of the stimulus as well as to its recollection. Studies such as these demonstrate clearly that memories associated with words and numbers are not localized in just one small part of the brain; rather, they involve activity in both hemispheres (for example, Okado & Stark, 2005).
Research with ERPs and ERFs indicates that injury to certain parts of the brain is asso- ciated with impairments in explicit memory. This research shows that the hippocam- pus appears to be essential for consolidating explicit memory and for spatial navigation (Knight, Waters, & Bandettini, 2009). Research conducted by Laczo and associates (2009) also suggests that impairment of hippocampal functioning might be an early indicator of Alzheimer’s disease.
Implicit memory, on the other hand, seems to be associated with other brain structures, such as the neocortex, amygdala, and cerebellum (Da Cunha et al., 2009). And the emo- tional aspects of memory seem to be closely related to the amygdala (Pouliot, 2010). Note, however, that the bulk of the evidence indicates that human learning—and consequently memory—is seldom associated with a single site in the brain. Even a learning task as simple as the classical conditioning of the eye-blink reflex involves activity and change in different brain structures. And dividing long-term memory into explicit, implicit, seman- tic, and autobiographical kinds of memory should not be taken as evidence that they nec- essarily involve different representational systems or different parts of the brain (Reder, Park, & Kieffaber, 2009).
Some of the puzzle pieces relating to the physiology and neuroanatomy of learning and memory have not yet been located—but researchers have a pretty good idea where to look. Research and theory have now led to the widely held view that memories are stored in changes in synaptic strength—that is, in changes in the probability that one neuron will activate another (Mozzachiodi & Byrne, 2010). In the current view, our minds are defined by incredibly complex networks of neurons that activate one another to make possible our thoughts, our emotions, and our very awareness of self.
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CHAPTER 5Section 5.2 Stages of Memory
Processes in Long-Term Memory
The memory system we have been describing has a simple goal: to make sense of important information and to store it so that it can be retrieved as needed. In this three-stage system, the first stage, sensory memory, serves simply to sense stimulation. The second stage, short-term memory, has the function of working memory; it is the conscious awareness stage where the effects of sensation are kept in mind long enough to be processed for storage into the third stage, long-term memory, and where information is retrieved from long-term memory to become conscious.
In effect, there are three cognitive processes that are important for encoding—that is, for changing sensory or other input into long-term memories: rehearsal, elaboration, and organization.
Rehearsal is repetition. It is one of the simplest memory strategies. If you say your lines over and over again, you might succeed in remembering them. But research suggests that if you want to remember for a long time, you should not do all your repeating at once; rather, you should space it out (Verkoeijen & Delaney, 2008). You are more likely to do well on your psychology exam if you spread your study over several days or weeks rather than if you try to cram it all into the night before.
Elaboration involves extending, changing, or adding to. One way of elaborating is to link mental images with what you want to remember. When Bradshaw and Anderson (1982) asked students to learn the sentence “The fat man read the sign,” those who had elabo- rated the sign to something like “The fat man read the sign warning of thin ice” remem- bered far better than those who had not elaborated.
Another way of elaborating is to reflect on the meaning and implications of events. But while elaboration might make information more memorable, it does not guarantee accu- racy of memories. Zaragoza, Mitchell, Payment, and Drivdahl (2011) gave participants misleading suggestions and asked them to elaborate on these suggestions by reflecting on the meaning and implications of what they had seen or read. For example, some partici- pants were asked to think about the implications of the thief’s having a gun—when the thief had no gun. Strikingly, the confidence with which participants thought these false memories to be accurate increased significantly.
Organization refers to grouping and arranging material. Suppose I ask you to learn this list: lemonade, poodle, tyrannosaurus rex, tea, chesapeake, ankylosaurus, dachshund, brontosaurus, milk. You might immediately have noticed that the list can quickly be orga- nized into three groups (dogs, drinks, and dinosaurs), and you will have realized that organizing it will make it much easier to remember.
These young actors will repeat their lines and movements until they remember them perfectly. Rehearsal (repetition) is a common long-term memory strategy. Elaboration and orga- nization are two others.
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CHAPTER 5Section 5.3 Forgetting
5.3 Forgetting
Sadly, rehearsing, elaborating, and organizing do not always guarantee that we will remember. In spite of our best efforts, there is much that we cannot recollect—and much, too, that we think we remember accurately but that is, in fact, hopelessly confused and distorted. There are a number of possible explanations for forgetting.
Fading Theory
One possibility is that we forget simply as a result of the passage of time, that whatever traces experience leaves among our neural networks gradually fade away. That we often remember recent events more clearly than distant ones is evidence for fading theory. For example, you can probably correctly describe more items in your current closet than in your closet 10 years ago. Unless you were in prison 10 years ago.
Most theorists do not consider fading theory (also called decay theory) very useful. They point out that it really says nothing about what causes forgetting because the passage of time, by itself, does not cause forgetting any more than it causes old cars to rust or glaciers to melt. Other things that happen during the passage of time cause these changes. Among them might be the fact that the brain functions less effectively with advancing age (Fried- man, 2003).
Repression
One of these other events might also be repression, Freud’s term for his belief that people sometimes banish from conscious memory highly unpleasant, anxiety-provoking (trau- matic) experiences. The theory holds that repressed material is not lost from memory— that it can continue to influence emotions and behaviors even though it cannot be brought to conscious awareness. This might be the case, for example, when adults experience difficulty remembering traumatic childhood experiences such as sex abuse (Woodiwiss, 2010). Freud argued that recovering these repressed memories is sometimes important for a healthy emotional life.
It is not clear how common repressed memories are, or how accurate recollections of these might be when they are later brought to mind through therapy. For example, Loftus’s (1997, 2007) research has uncovered many instances of apparent recollections of previ- ously repressed memories that are so highly distorted as to be largely false—hence the label false memory syndrome.
Loftus (1997) reports the case of a woman who went to a psychiatrist for help in coping with a traumatic experience her daughter had experienced. The therapist, using hypnosis, subsequently uncovered a range of traumatic experiences that the woman herself had experienced as a child. In the end, the woman “remembered” being raped, having sex with animals, being in a Satanic cult and eating babies, watching the murder of an 8-year- old friend, and on and on. Later, she realized that none of these things had actually hap- pened, that the memories had, in a sense, been planted by the hypnotist’s suggestions.
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CHAPTER 5Section 5.3 Forgetting
In one study, college students were asked what they remembered of some specific child- hood experiences from around age 5 that their parents had related to the investigators (Hyman, Husband, & Billings, 1995). They were told the study was designed to look at how people remember things differently. Each student was given one experience that the parents confirmed had not happened, along with several actual experiences. More than 80 percent of the participants still recalled details of the experiences that had actually hap- pened. And during a first interview, prior to being given any information, none recalled the false experiences. Strikingly, however, some 20 percent remembered details of the false “implanted” memories in a second interview.
False memory syndrome is especially important in courts of law, where witnesses, often children, are sometimes deliberately or inadvertently given misinformation that they later incorporate into their memories.
Distortion Theory
Much that we remember is vague and inexact. It is not so much that we lie; rather, we mis- remember. We confuse events, distort happenings, invent details. The distortion theory of forgetting recognizes that what we remember tends to be the gist, the main idea; we fill in the details and then we think we actually remember them. And sometimes we do.
But often we are mistaken. In one study, Loftus (1979) showed subjects a film in which a sports car is involved in an accident. Some participants were later asked, as might be any witness to an actual accident, “How fast was the sports car going when it passed the barn while traveling along the country road?” Others were asked, “How fast was the sports car going while traveling on the country road?” In fact, there was no barn along the country road, but fully 20 percent of those asked the first question later remembered seeing a barn.
Interference Theory
If subjects are required to learn two lists of nonsense syllables in succession, recall of either list will not be as perfect as if only one list were learned. If recall for the first list is found to be impaired, the assumption is that learning the second list has interfered with recall of the first (retroactive interference). If recall of the second list is less than might be expected, learning the first list is assumed to have interfered with recall of the second (proactive interference) (Tables 5.1 and 5.2).
Table 5.1 Testing Retroactive Interference
Time sequence Experimental group (A) Control group (B)
1. Learn X 1. Learn X
2. Learn Y 2. Do unrelated things
3. Recall X 3. Recall X
Note: Lower scores of group A relative to group B indicate the extent to which learning Y has interfered with the recall of X.
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CHAPTER 5Section 5.3 Forgetting
Table 5.2 Testing Proactive Interference
Time sequence Experimental group (A) Control group (B)
1. Learn X 1. Do unrelated things
2. Learn Y 2. Learn Y
3. Recall Y 3. Recall Y
Note: Lower scores of group A compared with group B indicate the extent to which X has interfered with Y.
Interference is a common cause of recall problems. For example, many beginning teach- ers can easily learn and remember the names of all their students. In later years, the task becomes progressively more difficult, probably because of the interfering effect of previ- ous learning (proactive interference). In addition, they now find it difficult to remember the names of students in their first classes (retroactive interference).
Retrieval-Cue Failure
More than once Ray Paul would show up at the store and the minute he got there he would say, “Dang, I forgot my wallet.” And his son, Andy, would show up at the ball park and the first thing he would say is, “Shoot, I forgot my glove.”
It is a common occurrence. A variety of things such as parks and stores serve as powerful retrieval cues: They jog our memories, remind- ing us of things we had meant to remember. Some researchers suggest that absence of cues—in other words, retrieval-cue failure—may be one of the most common causes of recall failure (for exam- ple, White, 2002).
As Homa (2008) explains, all learning takes place in a specific situation with accompanying sights, sounds, smells, and so on. Each of these can serve as powerful retrieval cues. That’s why wit- nesses are often taken to the scene of the crime, and sometimes why victims themselves go back. The hope is that the scene will serve as a retrieval cue—that it might jog memory.
As a summary of these theories of forgetting, consider again the analogy of the filing cabinet. This particular cabinet belongs to a large, long- established firm (it is an old person’s memory). Assuming that all pertinent material has been recorded (encoded and learned) and filed (stored
After many years in the classroom, the lecturer might find it more difficult to learn the names of new students because of interference from previ- ously learned names (proactive inter- ference). Also, she might now find it harder to remember the names of stu- dents from years past as she learns new names (retroactive interference).
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CHAPTER 5Section 5.4 Improving Memory
in memory), the clerk (old person) may experience various difficulties in retrieving appro- priate files when they are required. Some of the files have been in the cabinet for so long that they have simply deteriorated (fading theory). A number of the files might have been misplaced and are now in the wrong folders (distortion theory). Over the years, the filing systems have changed so that the clerk does not always know which system was used for the files she is looking for (retrieval-cue failure). Too, there are so many old and new files that many are hopelessly confused and cannot easily be sorted (retroactive and proactive interference). Finally, there are a number of entries dealing with scandalous revelations that have been blacked out so they cannot be read (although they might come to light with advanced forensic analysis) (repression theory).
5.4 Improving Memory
There is much in our knowledge of how human memory works that has direct implica-tions for improving memory. For example, the three strategies that are most useful for moving material from short- to long-term memory—rehearsal, elaboration, and organiza- tion—are strategies that learners can use systematically to improve long-term recall.
In the same way, each of psychology’s explanations for forgetting suggests specific strate- gies to increase duration and accuracy of retention, as is shown in Table 5.3.
Table 5.3 Theories of Forgetting and Some Educational Applications
Theory Explanation Possible Countermeasures
Fading Memory traces decay from disuse. Spaced repetition; review and relearn in a variety of settings over a period of time.
Repression Traumatic experiences are buried. Avoid trauma.
Interference Old memories interfere with new learning (proactive); new learning interferes with recall of old learning (retroactive).
Emphasize similarities and differences.
Retrieval Cue Failure Learner lacks cues that enable spe- cific recall.
Learn specific retrieval cues; practice some of the mnemonic aids described in this chapter.
Distortion We remember the gist and make up the rest so that memory changes over time.
Note the most important features of what is to be learned.
Mnemonic Aids
There are a number of relatively simple mnemonic aids (strategies to improve recall). Most of these are systematic retrieval cues; others are more elaborate coding systems that require more effort but that can lead you to prodigious feats of memory, and perhaps eventually to a stage career as a mnemonist. Do you think you could stand before a thousand people, have them name or show you 25 unrelated objects while your assistant writes their names in
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CHAPTER 5Section 5.4 Improving Memory
appropriate numbered spaces on a whiteboard out of your line of vision, and then recall each of these items in order, backwards, by odd or even numbers, or in any other order requested by your audience? You probably could. But first, you would have to master a mnemonic system, several of which are described here (see also Higbee, 1977; Holliman, 2009; Lorayne & Lucas, 1997; Yates, 1966).
Rhymes and Sayings Among the simplest of the mnemonic (memory- related) devices are rhymes: Thirty days hath Septem- ber. April, June, and November. . . . In fourteen hundred ninety-two, Columbus sailed the ocean blue. . . . Other simple mnemonic devices include acronyms and acrostics. Acronyms are letter cues such as NATO,
FBI, CIA, or Roy G. Biv (the colors of the visible spectrum in order). Acrostics are words, expressions, or sentences where initial letters stand for something else. For example, in Chapter 4, we used the acrostic IDEAL to represent five steps in solving problems.
These simple mnemonic devices provide important retrieval cues and also serve as a way of organizing, elaborating, and rehearsing material.
The Link System When we cannot remember something, we sometimes say, “I can’t quite picture it.” It is a highly revealing comment because our memory for images is striking. Standing (1973) showed his subjects as many as 10,000 different photographs. When he later showed them many of the same photographs but included others they had not seen, they successfully identified more than 90 percent of those they had already seen. But when the same sub- jects were asked to recognize words they had seen rather than images, their performance dropped significantly.
Not surprisingly, the most powerful memory systems are based on our ability to remem- ber images (Estrada, Keeley, & Leduc, 2007). These systems almost invariable require that you form a mental image of what you want to remember. Suppose, for example, you have a shopping list consisting of the following items: butter, bread, flour, sugar, thumbtacks, and dog food. Instead of taking the list to the store with you, or trying to memorize it, you could use the link system. It requires that you form vivid mental images linking each of these items. Picture, if you will, globs of butter smeared on a subdued slice of bread. Try to see the image as vividly as you can. It can be bizarre or very ordinary, the important point being that you should try to concentrate on the first image that suggests itself since that is the one you are most likely to recall first. Now link bread and flour. The slice of but- tered bread might be wrapped around a bag of flour; the flour might be in the sugar bowl, which is resting on a bed of thumbtacks. And now you see the thumbtacks protruding from a can of dog food (Figure 5.5b).
How many names of your first-grade classmates can you remember? It’s not an easy task. Recognizing their photos and linking names with them is far easier. Our impressive memory for images is the basis for some powerful mnemonic systems.
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CHAPTER 5Section 5.4 Improving Memory
The Loci System Despite its effectiveness and usefulness, the link method does have one major weakness: If you forget one item on the list, you may not be able to recall any of the subsequent items.
The loci system overcomes this limitation by placing strong visual images of items to be remembered in familiar locations—such as the rooms in your house (locus means “loca- tion” in Latin). You can then recall the items in the order in which you learned them if your mental walk through your house follows the same paths. And if you forget one of the items, you can still move to the next location and retrieve other items (Figure 5.5a).
The Phonetic System Among the most powerful of mnemonic systems is the phonetic system, a system often used by professional stage memorizers. The first step in learning this system is to develop and completely learn your own strong visual associations between numbers and conso- nants and then between numbers and simple, highly memorable words. In this system, consonant and number links are usually based on the appearance of the consonant. Thus, 1 is a t (because it has one down stroke); 2 might be n; 3, an m; 4, a q, and so on.
Once you have associated a number with each consonant (vowels do not count), you can then form a word for each number, say, from 1 to 25. For example, number 1 might be TOE, 12 could be TIN, and 21, NUT. Now form a strong visual image linking each of these words to its number. Learn these thoroughly, practice them, and then challenge
Kitchen Dining Room
Office Bedroom
a b
Figure 5.5
Two mnemonic systems. (a) The loci method involves putting each object in an imaginary location in a familiar environment—such as your house—and then taking a mental room- by-room tour. (b) The link system involves constructing a visual image that connects all the objects to be remembered.
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CHAPTER 5Section 5.5 What Is Intelligence?
your tormenters to name, or show you, 25 different items, which they can write down, numbered consecutively. Not only will you be able to recall them forward or backward, but if they want to know what the 21st item was, you can immediately say, “Oh, that’s the hammer, the red-handled one,” as you visualize your poor NUT about to smashed.
A professional mnemonist’s course might not teach you much more.
5.5 What Is Intelligence?
But you do have to be reasonably intelligent to learn the phonetic system. Does that mean you have to have a high intelligence quotient (IQ)? Just what is intelligence? Is IQ the best measure of intelligence?
Myths about IQ
Or, just as important, what is not intelligence? What beliefs are mythical? Which ones might be puzzle pieces that mislead us and that should be discarded?
Myth 1 IQ is synonymous with intelligence. Not true. IQ is just a score on an “intelligence” test. These tests do not always measure very accurately, and they do not always measure what they are intended to measure. Although they reflect some of the characteristics of what we think of as intelligence, they may also be influenced by factors such as mood, fatigue, and motivation. Hence IQ and intelligence are not synonymous.
Myth 2 IQ tests measure everything that is important for intelligent behavior. Unfortunately, intelli- gence tests seldom tap abilities such as creativity, perseverance, motivation, and emo- tional or social skills—all fundamentally important components of what Sternberg (2005) describes as practical or successful intelligence.
Myth 3 IQ tests are fair and impartial. They should be, but, sadly, many are culturally biased. That’s because they have usually been developed and standardized with white middle-class children, and therefore tend to favor them. Note, however, that more recent revisions of the most widely used intelligence tests often include a variety of minority groups in their standardization samples to increase their fairness.
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CHAPTER 5Section 5.5 What Is Intelligence?
Myth 4 IQ is more or less fixed. What we have is what we have. It is dangerous to believe this myth because, as Dweck (2006) points out, if we believe this, we will make no efforts to increase our intelligence. And if we find a task difficult, we are likely to give up rather than try to master it. That is, if we think intelligence is fixed, we need to believe we have more than an average amount if we are to have the confidence to undertake challenging tasks.
That IQ is not fixed is apparent not only in the fact that people’s measured IQs can change dramatically, but also in the observation that measured IQ throughout the world has been increasing at the rate of about 3 IQ points a decade, a phenomenon known as the Flynn effect (Flynn, 1994; Flynn & Weiss, 2007) (Figure 5.6). The reasons for this phenomenon are not clear. Better school programs, improved nutrition, increasing familiarity with tests, and stimulation from technology and media may all contribute.
Not a Myth IQ predicts success, both in life and in school. While considerable research supports this conclu- sion (for example, Deary, Strand, Smith, & Fernandes, 2007), this does not mean that IQ is the only, or even the most important, predictor of future success. Motivation, personality charac- teristics, and previous achievement may be even more important (Thorndike & Hagen, 1977).
A ve
ra g
e M
ea su
re d
IQ
Projected measured IQ 1932 through 2017, if 1932 IQ tests had not changed
80
85
90
95
100
105
110
115
120
125
130
Figure 5.6
The Flynn effect: Measured intelligence has been increasing at about 3 IQ points per decade. If our 1932 measures of IQ had not been revised and renormed, our average measured IQ would now be over 120!
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CHAPTER 5Section 5.5 What Is Intelligence?
Views of Intelligence
When psychologists and related “experts” were asked, way back in 1921, what they thought intel- ligence was, most agreed that it had to do with the ability to learn and to adapt. And when another group was asked the same question 65 years later, they responded in much the same way, although many now added that the individuals’ awareness of their own cognitive processes and their ability to monitor and control these processes were also important (Sternberg & Kaufman, 1998).
In spite of this apparent agreement, there have been a wide range of different definitions and views of intelligence.
Successful Intelligence: Sternberg The best approach, suggests Sternberg (2006), is to look at people who are most successful in adapting to the world. If we do that, we find that these people are those who not only learn well, but who are adept at selecting and even at shap- ing the world to maximize their success. What they have is successful intelligence as opposed to psychometric, or measured, intelligence. Note how this view emphasizes adaptation. What it says, in
effect, is that the most intelligent people are those who are most successful in choos- ing or changing their environments or their goals to match their abilities. It would not be intelligent for someone with an uninspiring and uncontrollable voice to strive for a career as a singer, although it might be quite intelligent for the same person to become a pianist.
Successful intelligence requires that the individual be able to evaluate options, devise strategies for attaining goals, and assess the extent to which goals are being met. In other words, it requires analytical abilities, and it also requires creative abilities. These make it possible to invent strategies, to uncover new options, to find ways of selecting and shap- ing the environment.
Finally, successful intelligence requires the sorts of practical abilities that are involved in carrying out options, in putting into practice the behaviors and skills that are required for selecting, shaping, and adapting to environments.
These three groups of abilities—analytical, creative, and practical—make up the three com- ponents of what Sternberg labels the triarchic theory of successful intelligence. It is a
It is not a myth that measured IQ pre- dicts success; witness this Columbia doctoral graduate with a high IQ. But it is a myth that it is a fixed quality that cannot be improved.
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CHAPTER 5Section 5.5 What Is Intelligence?
theory that highlights the importance of adaptation; it also emphasizes creative and prac- tical abilities, features that conventional intelligence tests typically do not take into con- sideration (Figure 5.7).
This view of intelligence has the advantage of making the concept less abstract and theo- retical. It brings it to a more concrete, more easily understood level. It also has the advan- tage of emphasizing that intelligence is not a fixed, unchanging quality about which we can do nothing. In this view, intelligence is a little like a box of tools that we use to play the game of cognition. We might each have very different tools in our boxes, but we can certainly learn to take advantage of the ones we do have. And we might also learn from how others use their tools.
Multiple Intelligences: Gardner Gardner points out that if you ask people how smart they are, many will hesitate. Why? Because it depends on what they think you mean. If, instead, you ask not “How smart are you?” but rather, “How are you smart?” the answer might be more immediate and more revealing. Now the person can say, “Hey, I’m really good at math.” Or, “I’m smart when it comes to remembering names.” Or, “Well, compared to my brother, I’m pretty smart.”
We don’t have just one kind of “smarts,” explains Gardner (2006). We have at least eight largely unrelated kinds of intelligence: logical-mathematical, linguistic, musical, spatial, bodily kinesthetic, naturalistic, interpersonal, and intrapersonal. Their characteristics are summarized in Figure 5.8.
Sadly, our schools tend to ignore many of these abilities. And when we try to measure intelligence, we overlook most of them as well, says Gardner. Mostly, we concentrate on logical and linguistic abilities; most of the other abilities cannot easily be measured with our paper-and-pencil tests.
Figure 5.7
The three arches of Sternberg’s triarchic view of successful intelligence.
Analytical Abilities
• Analyzing, evaluating, comparing, contrasting. . .
Creative Abilities
• Inventing, discovering, imagining, creating. . .
Practical Abilities
• Putting into practice, using, doing. . .
Successful Intelligence: A balance among selecting
and shaping the environment and adapting it to achieve social and personal goals.
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CHAPTER 5Section 5.5 What Is Intelligence?
Gardner’s Eight Kinds of
Intelligence Main
Characteristics Possible
Occupations
Logical-mathematical intelligence
Linguistic intelligence
Musical intelligence
Spatial intelligence
Bodily kinesthetic intelligence
Interpersonal intelligence
Intrapersonal intelligence
Naturalistic intelligence
Scientist; Mathematician;
Accountant
Orator; Poet; Journalist; Texbook writer
Composer; Musician; Pop star
Graphic designer; Architect; Artist
Dancer; Athlete; Bullfighter; Fashion
designer
Teacher; Psychologist; Lawyer
Guru; Writer; Philosopher
Biologist; Evolutionary theorist; Archeologist
Ability to think logically, to reason
Ability to generate and understand oral and
written language
Appreciation and/or production of musical
forms
Ability to manipulate and understand mental
representations
High degree of coordination and
bodily control
Ability to discern emotion in self and others and respond appropriately
High self-knowledge, strengths, weaknesses,
and emotions
Ability to detect patterns and organization in
nature
Figure 5.8
Gardner’s eight kinds of intelligence, their characteristics, and possible occupations. Gardner also explored the possibility that there might be an additional type of intelligence dealing with existential questions (relating to spirituality and the purpose of life), but he concluded that it did not meet the criteria for inclusion among the eight intelligences.
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CHAPTER 5Section 5.6 Measuring Intelligence
5.6 Measuring Intelligence
Intelligence tests are used mainly for prediction. In a sense, an intelligence test score is a prediction that an individual will do well or less well on tasks requiring intelligence.
The IQ
Most intelligence tests yield one or more IQ scores. The concept of the IQ is quite simple as it was originally defined and calculated. The reasoning went as follows: A child who can understand and solve problems that average 5-year-old children are capable of solv- ing may be said to have a mental age of 5. Now if that child’s chronological age happens to be 5, we can conclude that this is an approximately average child. The ratio of this child’s mental age to chronological age (that is, mental age divided by chronological age) is 1. Multiply that by 100 and there you have it, an IQ of 100—which is the IQ of large, average samples.
If the child were 4 but performing at the level of average 5-year-olds, IQ would be 5/4 × 100 = 125; but if this were a 6-year-old child performing at that level, IQ would be 4/5 × 100 = 80.
The earliest recognized measure of intelligence was based on this reasoning and calcula- tion. Alfred Binet and Théodore Simon, two French psychologists, developed the first recognized intelligence test in 1905. The test consisted of sets of questions they devised, arranged in increasing order of difficulty, and allocated to different age levels. All items that 65 to 75 percent of the 5-year-olds passed were placed in the 5-year level, and so on. Mental age was computed simply by presenting children with these questions until they reached levels too difficult for them.
Now almost all intelligence tests assign IQs not on the basis of mental age but simply on the basis of comparisons with the scores of other children. Typically, IQ scores can be read directly from tables, based on the child’s age and actual score on the test. Tests are standardized in such a way that the average for any large group is around 100 with about two thirds of all individuals scoring within 15 points on either side of the average (that is, between 85 and 115). The normal distribution for intelligence is shown in Figure 5.9.
IQ Tests
Of the many intelligence tests available, some yield a single IQ score; others are designed to measure more specific aspects of intellectual functioning and yield a variety of scores indicating aptitude in different areas, such as verbal comprehension, logical reasoning ability, memory, and so on.
There are two general types of intelligence tests. Individual tests can be given to only one individual at a time; group tests are designed for large groups. Individual tests typi- cally require a trained tester, are very time consuming, and are therefore expensive to administer. Most have relatively high validity (an indication of the extent to which they measure intelligence rather than something else) and reliability (the accuracy of their
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CHAPTER 5Section 5.6 Measuring Intelligence
measurement) (Canivez, Konold, Collins, & Wilson, 2009). They are especially useful for identifying exceptional talent and for diagnosing learning problems (Shavinina, 2009). The best-known individual intelligence tests are the Stanford-Binet, currently in its fifth revision, and the Wechsler Intelligence Scale for Children (4th ed.) (versions are available for preschoolers and for adults). Both can be administered only by trained professionals.
Group tests, which are typically paper-and-pencil or computer administered, can usu- ally be administered by anyone. As is the case for individual tests, the scores they yield can then be interpreted using tables provided by test makers. The Cognitive Abilities Test (CogAT) is one of dozens of widely used group intelligence tests. Another is the Goodenough-Harris Drawing Test (Harris, 1963), which provides a measure of intelli- gence based on the child’s drawings of a person. Drawings are judged in terms of factors such as detail, proportion, and presence or absence of specific body parts, all of which reveal the child’s conceptual sophistication. It has the advantage of being nonthreatening and nonverbal, and can therefore be used with children from different cultures or those who might have language problems. Research indicates that it correlates reasonably well with other measures of intelligence and with school achievement (Oakland & Dowling, 1983). Some studies suggest that it might also be useful in identifying mental retardation (Naglieri, 1988) (Figure 5.10).
Misuses and Abuses of Tests
Intelligence tests are among the best tools we have for predicting academic success (Kun- cel, Ones, & Sackett, 2010). Unfortunately, however, they are less than perfectly valid and reliable, they are often misunderstood and misused, and their use is sometimes highly
N u
m b
er o
f ca
se s
IQ 55 70 85 100 115 130 145
0.13%
2.15% 2.15%
13.59% 13.59%
34.13% 34.13%
2.15% 2.15%
13.59% 13.59%
34.13% 34.13%
Figure 5.9
A normal curve depicting the theoretical distribution of IQ scores in an unselected group. Average score is 100; 68.26 percent of the population score between 85 and 115; only 2.29 per- cent score either above 130 or below 70.
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CHAPTER 5Section 5.6 Measuring Intelligence
controversial. Some of the reasons for the controversy are apparent in the very strong reac- tion to books such as The Bell Curve (Herrnstein & Murray, 1994) and The Global Bell Curve (Lynn, 2008). The main idea in these books is that IQ is a clear and important predictor of success in a wide variety of endeavors, including school, parenting, and business, that it is highly related to poverty and low socioeconomic status, that it predicts things such as the probability of being on welfare and of having unwanted children, and that it is inherited and reflects important racial differences in intelligence.
For many, these are inflammatory, inaccurate, and socially dangerous notions. Critics have been quick to reject the notion that IQ tests identify those who will fail and that they separate people on the basis of race.
But there is agreement with some of the less politically dangerous conclusions. IQ tests properly developed, used, and interpreted need not be biased against any group. And they can be very useful for important decisions such as school placement, college admis- sion, job placement, and scholastic awards. In one sense, IQ tests are impeccably objective and impartial. The tests do not know whether the testee is rich or poor, brown or yellow, male or female. And they really do not care.
4 years, 7 months 4 years, 9 months 5 years, 9 months
Figure 5.10
The Goodenough-Harris Draw-A-Person test is a nonthreatening way of assessing the child’s conceptual sophistication. It provides a quick estimate of IQ. Note how this boy’s drawing of himself changed in the 14 months represented by these three drawings.
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CHAPTER 5Section 5.7 Influences on Intelligence
5.7 Influences on Intelligence
There are two great forces that shape what we become: heredity and environment. Untangling and sorting out the contributions of each to the development of intelli- gence has been difficult and controversial, and it has occupied a great deal of the time and effort of those dedicated to finding pieces of the human puzzle.
Unfortunately, it is not possible to devise an experiment where an investigator can sort out sequences of DNA and combinations of genes and then give each subject a different assortment so as to observe the effect of so doing on intelligence. Nor is it possible to assign subjects to different environments, say, group A to an impoverished situation and group B to a wealthy and privileged environment.
Heredity and Environment
But we do have a naturally occurring phenomenon that has proven invaluable for sepa- rating genetic from environmental influences: twins. That is because monozygotic twins are genetically identical, a condition that is not true for any other pair of humans includ- ing dizygotic twins, which are fraternal rather than identical. So, if intelligence is caused mainly by heredity, monozygotic twins should have almost identical IQs (except for errors of measurement). But if environment is more important, then fraternal twins should be as similar as identical twins.
Furthermore, when identical twins are raised together, both their environments and their genes are highly similar. But when they are raised apart, genes remain identical but envi- ronments differ.
There have been a very large number of twin studies designed to unravel the contribu- tions of heredity and environment. Several of these are summarized in Figure 5.11. Note that in that summary, correlation coefficients are consis- tently higher for monozygotic than for dizygotic twins—strong evidence that intelligence is influ- enced by genes.
But note, too, that twins resemble each other more when younger than when older—strong evidence that the environment exercises increasing influ- ence with the passage of time.
A second group of studies provides additional clarification. These studies look at the correla- tion between intelligence test scores of adopted children with both their adoptive parents, with whom they share an environment, and their bio- logical parents, with whom they share genes but not an environment. These studies typically find
Physically, monozygotic twins are often nearly identical—right down to the hair and the facial expressions in this instance. They’re also remarkably similar in measured intelligence and on various personality traits—strong evidence of the power of genetics in determining human characteristics.
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CHAPTER 5Section 5.7 Influences on Intelligence
a higher correlation between adopted children and biological parents than between adopted children and adoptive parents—again strong evidence of the importance of heredity (Figure 5.12).
The Rubber-Band Hypothesis While studies such as these show clearly that genes are important determiners of charac- teristics such as intelligence, they also provide clear evidence that experiences also con- tribute. A good analogy to describe the relationship between the two is Stern’s (1956) rubber-band hypothesis. It compares our inherited potential to a rubber band whose final length represents our manifested intelligence. A very good environment can stretch the band a long ways; a poorer one, not so much (Figure 5.13).
Of course, some bands stretch more easily than others (better genetic endowment); others, sadly, are quite frail and perhaps even a little brittle right from the beginning.
Age at time of testing
Monozygotic
Dizygotic Opposite Sex
Dizygotic Same Sex
C o
rr el
at io
n c
o ef
fic ie
n ts
s h
o w
in g
si
m ila
ri ty
b et
w ee
n t
w in
s
2 3 4 7 9 10
0
10
20
30
40
50
60
70
80
90
100 93
81 76
91
76 73 73
77
90
65
75
59 55
72
53 49 46 45
Figure 5.11
Similarity coefficients for intelligence test scores for more than 6,900 twin pairs. Based on data reported in F. M. Spinath, A. Ronald, N. Harlaar, T. S. Price, & R. Plomin (2003). Phenotypic g early in life: On the etiology of general cognitive ability in a large population sample of twin children aged 2–4 years. Intelligence, 31, 195–210; and in O. S. P. Davis, R. Arden, & R. Plomin (2008). g in middle childhood: Moderate genetic and shared environmental influence using diverse measures of general cognitive ability at 7, 9, and 10 years in a large population sample of twins. Intelligence, 36, 68–80.
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CHAPTER 5Main Points
Main Points 1. What Is Memory? Memory is the storage, the retention, and the ability to retrieve
the effects of experience. 2. Stages of Memory: The most common model of memory describes three stages:
sensory memory (fleeting effects of sensation); short-term memory (immediate, conscious awareness whose functioning is described as working memory where a central executive system oversees the operation of the phonological loop and the visual-spatial sketch pad, which maintain verbal and visual material available for processing); and long-term memory (stable, highly generative, lasting memories that can be implicit or explicit). Explicit memory may be semantic (general knowl- edge) or autobiographical (personal recollections tied to time and place). Event- related fields and event-related potentials indicate that different parts of the brain are more involved than others in certain kinds of memories.
3. Forgetting: Inability to recall may be due to fading (time-related changes); repres- sion (relegation of traumatic experiences to the subconscious, sometimes recalled later, occasionally as a false memory); distortion (we remember only main ideas and generate the rest, sometimes distorting and confusing recollections); interference
C o
rr el
at io
n
Adopted child/ adoptive parents
Adopted child/ biological parents
0.00
0.03 0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.38 0.40
M an
if es
t in
te lli
g en
ce Quality of environment
Poor Average Good
Lo w
M ed
iu m
H ig
h
High genetic endowment
Low genetic endowment
Figure 5.13
The Stern rubber-band hypothesis. People with different inherited potentials can develop below-average, average, or above- average intelligence depending on environ- mental forces.
Figure 5.12
Correlations in late adolescence for general cognitive ability. Based on R. Plomin, D. W. Fulker, R. W. Corley, & J. C. DeFries (1997). Nature, nurture, and cognitive development from 1 to 16 years; A parent-offspring study. Psychological Science, 8, 442–447.
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CHAPTER 5Main Points
(where past or subsequent learning interferes with recall); or retrieval-cue failure (where we do not have the right cues to jog our memories). Organizing, elaborat- ing, and rehearsing can improve long-term memory, as can various mnemonic aids such as rhymes, acronyms, acrostics, and more elaborate systems like the link, the loci, and the phonetic.
4. What Is Intelligence? It is not synonymous with IQ, IQ tests do not measure all that is important, they are not always fair, and IQ is malleable. It does predict academic achievement. Successful intelligence (Sternberg) is an adaptive quality that requires analytical, creative, and practical abilities. We may have as many as eight distinct kinds of intelligence (Gardner).
5. Measuring Intelligence: Average IQ is 100 as measured by group and intelli- gence tests, all of which have less than perfect validity and reliability. They have sometimes been misused and misinterpreted.
6. Influences on Intelligence: Heredity and environment are the two great forces that shape intelligence.
Study Terms
amnesiacs
autobiographical memories
central executive system
chunking
declarative memory
distortion theory
dizygotic twins
elaboration
encoding
event-related fields (ERFs)
event-related potential (ERP)
explicit memory
fading theory
false memory syndrome
flashbulb memories
Flynn effect
forgetting
group tests
implicit memory
individual tests
intelligence quotient (IQ)
link system
loci system
long-term memory (LTM)
memory
mnemonic aids
mnemonist
modal model of memory
monozygotic twins
nondeclarative memory
nonsense syllables
normal distribution
organization
phonetic system
phonological loop
proactive interference
rehearsal
reliability
repression
retrieval cues
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CHAPTER 5Main Points
retrieval-cue failure
retroactive interference
semantic memory
sensory memory
short-term memory (STM)
triarchic theory of successful intelligence
validity
visual-spatial sketch pad
working memory
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6
Motivation and Emotion
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • What does the term motivation mean? • How are instincts and reflexes different? • How are needs and drives related? • What is Maslow’s hierarchy of human needs? • What is cognitive dissonance theory? • How are achievement motivation and attribution theory related? • What is the meaning and importance of self-efficacy? • What are the main theories of emotion? • How does arousal relate to behavior? • What are the common eating disorders?
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CHAPTER 6Motivation and Emotion
We would frequently be ashamed of our
good deeds if people saw all of the motives that produced them.
—Francois De La Rochefoucauld
Chapter Outline
6.1 What Is Motivation? A Definition
6.2 Physiological and Behavioristic Approaches Instincts Psychological Hedonism Needs and Drives
6.3 Maslow’s Hierarchy
6.4 Cognitive Views Cognitive Dissonance Theory Achievement Motivation Attribution Theory Self-Efficacy
6.5 Emotions Arousal What Is an Emotion? Theories of Emotion Emotional Control
6.6 Hunger and Sex Drive Hunger Stimuli Obesity Anorexia, Bulimia, and Binge Eating Disorder Sexual Motivation
Monsieur De La Rochefoucauld may have had a point.
There is no shortage of good deeds to look at. People spend tens of billions of dollars each year on gifts; politicians generously give their time to charitable events; friends buy each other dinner or carry each other’s bags. On the surface, good deeds all, motivated by selfless love and generosity.
Or are they entirely good deeds? Is it possible that the real motives for these behaviors are not always what they seem? Do we sometimes give gifts mainly because we want something in return? When Evelyn says she will buy dinner for Edward because he helped her study, is that truly her motive? Or is her motive the hope that he will invite her on his yacht? Does Robert carry his friend’s bag because he is younger and stronger and genuinely likes to help? Or is he driven by the urge to have a look at what’s inside? How likely is it that the fund-raising politician is moved more by a desire to be reelected than by basic charitable impulses?
How many of our behaviors are driven not by their apparent motives, but by ulterior motives?
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CHAPTER 6Section 6.2 Physiological and Behavioristic Approaches
6.1 What Is Motivation?
By definition, ulterior motives are hidden: They are motives of which, as De La Roche-foucauld suggests, we would be ashamed were they made public. In fact, there is the possibility that some of our ulterior motives are so well hidden that even we don’t recog- nize them.
Historically, psychology has not concerned itself much with ulterior motives; it prefers pieces of the puzzle that are more easily exposed—motives such as hunger and sex and our need for affection and achievement. But in its search for the forces that drive our behavior, it sometimes uncovers hidden motives.
A Definition
The forces that drive us to action define motivation. The term derives from the Latin verb movere, which means “to move.” Hence motivation deals with the forces, conscious or otherwise, that underlie our behaviors. Motivation theorists try to understand why we do certain things and not others, what instigates behavior, and why it stops.
Motives are very closely tied to emotions. Clearly, complex combinations of feelings such as hate, fear, love, disgust, anger, and on and on are the reasons for much of what we do.
6.2 Physiological and Behavioristic Approaches
Early motivation theorists looked at biology and behaviorism for their explanations. It seemed to them that certain basic instincts and drives that we inherit might account for much of our behavior.
Instincts
After all, they reasoned, we are animals, and many animal behaviors appear to be bio- logically determined: migration in birds and butterflies; spawning and nesting in fish and fowl; mating in mouse and man; and on and on. These complex behaviors, labeled instincts, are common to all members of a species, are apparently unlearned, and are little affected by experience (Figure 6.1).
Many theorists, including William James (1890/1950), listed an enormous number of human instincts, among which were tendencies toward jealousy, cleanliness, clasping, biting, sucking, and even kleptomania! At one point, Bernard (1924) counted more than 6,000 human instincts. But most of these are not instincts at all. They’re not common to all members of our species, and they don’t remain unchanged by experience. They have little in common with instincts such as migration or nesting. Furthermore, lists of instincts explain very little about human behaviors. To say that we are jealous because we have a jealousy instinct does nothing to explain our jealousy: It merely labels it. This is what is called the nominal fallacy—the assumption that naming something explains it.
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CHAPTER 6Section 6.2 Physiological and Behavioristic Approaches
The nominal fallacy is not uncommon in psychology. To say, for example, that Robert sets fires because he is a pyromaniac or that Sandra has trouble learning because she is mentally challenged or that Nora does not eat because she is anorectic does not explain a single one of
Trigger instinctual tendencies
Which lead to predictable behavior
Environmental conditions
Activates migratory instinct in geese
They fly southDays become shorter
Figure 6.1
The instinct model. It is no longer a popular explanation for human behavior.
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CHAPTER 6Section 6.2 Physiological and Behavioristic Approaches
these behaviors: It merely labels it. To attribute fighting to an aggressive instinct is, in the final analysis, no more revealing than to say that people fight because they fight.
Although instincts are now studied in relation to animal rather than human behavior, many psychologists argue that inherited biological tendencies play an important role in human behavior. As we saw in Chapter 2, for example, evolutionary psychologists point out that biology “prepares” us to learn certain things such as language or aversions to bitter-tasting and possibly poisonous foods, or fear of snakes. Others suggest that our ten- dencies toward aggressiveness and toward eating too much of the wrong things may also have a biological basis (van Honk, Harmon-Jones, Morgan, & Schutter, 2010).
Psychological Hedonism
Another historical approach to explaining human behavior rests on the appealing and obviously true idea that people usually behave so as to achieve pleasure and to avoid pain. This notion, labeled psychological hedonism, or the pain-pleasure principle, seems, at first glance, to be a good explanation for human behavior, supported both by science and by anecdotal evidence (Riediger, Schmiedek, Wagner, & Lindenberger, 2009).
But, by itself, it explains nothing. Basically it says that whatever we do, we do because doing so is pleasurable now or is expected to lead to pleasure in the future, or because it move us away from pain or is expected to move us away from pain in the future. The problem with this explanation is that it does not lead to any valid predictions or explana- tions unless pain and pleasure can be defined beforehand. But these are subjective states, not easily defined. If The Great Magician Mammoon eats broken bottles, we must assume that he, too, is driven toward pleasure and away from pain, but we might have been hard pressed to predict his glass-eating behavior in the first place.
Needs and Drives
Still, there are clearly some common elements in our estimates of what is pleasant and unpleasant. As we saw in Chapter 4, certain stimuli, including food, drink, praise, and 50-dollar bills, are likely to be positive reinforcers. These are stimuli that satisfy our various needs. Hence, they are motivating: they provide a behavioristic explanation for our actions.
Physiological Needs One way of looking at needs is to say that they drive behavior. Thus, the need for food gives rise to a hunger drive; for drink, to a thirst drive; and for sex, to a sex drive. These are basic physiological needs. From a hedonistic point of view, satisfaction of a basic need may be described as pleasurable and failure to satisfy a need as unpleasant.
That physiological drives are related to actual needs is clear with respect to hunger and thirst. Deprivation of food and water leads to detectable physiological changes that are responsible for our awareness of the needs. Drinking or eating then leads to a reduction in the drive—hence the label drive reduction. But that there is more to hunger and thirst
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CHAPTER 6Section 6.2 Physiological and Behavioristic Approaches
than simple physiology and drive reduction is also clear. As we see later, a host of external stimuli, as well as cognitive and emotional states, contribute to our eating and drinking behaviors (Figure 6.2).
With respect to sex, the picture is much murkier. Sexual deprivation is not accompanied by tissue changes, although sexual urges are clearly influenced by hormonal factors. Perhaps much more important for humans, however, are the varieties of other factors—cognitive, emotional, perceptual, and cultural—that are inextricably linked with sexual behavior.
Psychological Needs While the basic physiological needs seem clear, there is less agreement about what our psychological needs are. Likely candidates include the need for affection, belonging, achievement, independence, social recognition, and self-esteem.
Need (Lack of food; lack of water)
Drive (hunger; thirst)
Behavior (eating; drinking)
Satisfaction of Need (drive-reduction)
Figure 6.2
The drive-reduction model of motivation.
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CHAPTER 6Section 6.2 Physiological and Behavioristic Approaches
Research supports the notion that outcomes such as emotional well-being and academic achievement are linked with satisfied psychological needs (Faye & Sharpe, 2008). How- ever, unlike physiological drives that can be assumed to be common to most individuals, it is not entirely clear that everyone has the same psychological needs. In fact, many of these needs appear to be at least partly, if not entirely, learned. As a result, some people seem to have a higher need for acceptance or for achievement or for love than others.
Note, too, that physiological needs can be entirely satisfied, at least temporarily: You can eat or drink until you absolutely don’t want any more. Psychological needs, on the other hand, are not so easily satisfied. Few people are ever totally sated with love or achieve- ment or affection.
One of the weaknesses of earlier drive-reduction explanations is that they attributed behavior to tensions that accompany inner states and that are subsequently reduced as a result of appropriate behaviors. But even hunger is not entirely an internal state. If it were, people would always eat only as much as required to activate the physiological mecha- nism that says, “Whoa, you’ve had enough.” But no, many people eat far more if the food looks and tastes especially good.
And some eat more if they’re given a small appetizer first, even though the appetizer should have begun to reduce the hunger drive. Even rats will run a little faster toward the goal box when given a taste of food beforehand (Zeaman, 1949) (Figure 6.3). Why? Because the food has incentive value; it provides the rat with incentive motivation.
A. B.Incentives (goals, rewards, anticipation of
rewards)
Goal-related behaviors
Figure 6.3
Drives alone cannot explain some behaviors. In Zeaman’s 1949 study, rats that had already been given some food (b) performed better on a maze they knew led to food than did presum- ably hungrier rats (a).
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CHAPTER 6Section 6.3 Maslow’s Hierarchy
Basically, incentive relates to the subjective value of a goal or reward. The higher the value, the greater the incentive; hence the more motivating the goal or reward.
That different goals have different incentive value is evident in the fact that monkeys typically work harder to obtain a banana than a piece of lettuce (Harlow, 1953)—and that humans willingly pay more for a steak or a lobster than for a bowl of soup. These have more incentive value for us. Nor do we have to be given a taste beforehand, gifted as we are with imaginations; we can anticipate the consequences of our behavior. And there is little doubt that our anticipations are powerful influences in directing our activities. Anticipation underlines the importance of the cognitive aspects of motivation.
6.3 Maslow’s Hierarchy
Maslow (1970) suggests that human actions may be accounted for by two systems of needs: the basic needs, and the metaneeds. The basic needs are called deficiency needs because when they are unsatisfied, they lead to behaviors designed to satisfy them. They include both physiological needs (food, drink) and psychological needs (security, love, and self-esteem).
Metaneeds are higher-level needs; they include cognitive needs, aesthetic needs, and the need for self-fulfillment. They’re called growth needs because activities relating to them don’t result from deficiencies, but from the organism’s tendency toward growth.
According to Maslow, needs are hierarchically arranged as shown in Figure 6.4. What this means is that lower-level needs must be satisfied before other needs are attended to. Thus, a starving person might not hunger for knowledge or self-esteem—only for food (Harper & Guilbault, 2008) (Figure 6.4).
Maslow was concerned with developing a theory that would encompass the more “human” qualities of behavior that define our “higher nature.” We have an overpowering tendency toward growth, explains Maslow. This defines our very essence and is abso- lutely fundamental to mental health and happiness. The highest and most important of our growth needs is the need for self-actualization (discussed in Chapter 8).
Unlike the more basic needs, whose satisfaction can be ensured through appropri- ate activities (eating, for example), self-actualization, as a need, is never satisfied. Self- actualization is rarely an achieved state but more an ongoing process. Depiction of Maslow’s theory as a triangle is misleading, explains Rowan (1998), because it implies an end point to personal growth. Hence the open triangle and the ladder in Figure 6.4.
6.4 Cognitive Views
Some early behavioristic positions tended to view us as passive victims of forces over which we have little control. Motives were seen as internal or external prods that pushed us this way and that.
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CHAPTER 6Section 6.4 Cognitive Views
Cognitive positions present a more active view of the human animal. They take into account the wealth of human emotions involved in behavior, dealing with these not as forces over which we have no control, but as feelings that we actively and sometimes very consciously manipulate. The cognitive theorist tries to understand the sequence of ongoing human behavior as it is mediated and controlled by ongoing cognitive activity, of which affect (emotion) is a central component.
Self- Actualization
Goodness Beauty Truth Justice
Aesthetic
Knowleddge Syymmetrry
Cognitive
Competence ApprovalRecognition
Self-Esteem
Affiliationn Acceptance Affection
Belongingness and Love
SecurityPsychological safety
Safety
Food Drink
Physiological
M et
an ee
ds
B as
ic N
ee ds
(G row
th N eeds)
(D eficiency N
eeds)
Figure 6.4
Maslow’s hierarchy of needs. That the pyramid is open shows that self-actualization is a never- ending process. From Maslow, Motivation and Personality, 3rd ed. Copyright © 1987. Printed and electronically reproduced by permission of Pearson Education, Inc., Upper Saddle River, New Jersey.
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CHAPTER 6Section 6.4 Cognitive Views
Note, however, that not all behavioristic positions view the organism as totally passive and reactive. Even Skinner’s rat is an active organism that explores the environment and that emits responses rather than simply reacting blindly to external forces. The main con- trast between behavioristic and cognitive approaches to motivation is that the cognitive theorist looks at the role of rewards and punishments in terms of the individual’s under- standing and anticipation. In so doing, cognitive theories take into account what might well be the single most powerful explanatory concept in human motivation: our ability to delay gratification. Doing so involves thinking, imagining, and self-verbalization—some uniquely human activities.
Cognitive Dissonance Theory
Festinger and Carlsmith (1959) asked college students to perform an extremely boring and apparently pointless task as part of an experiment. They were then divided into three groups, one of which did nothing further, serving as a control group. The remaining two groups were asked to help the experimenter by lying to some new subjects, telling them that the experiment was interesting, exciting, and useful. All agreed to do so. For their services, one group of subjects was paid $20; the other group, ignorant of how much the others had been paid, was given a single dollar.
After members of these two groups had each spoken to the “new” subjects (actually con- federates of the investigators), they were interviewed to uncover their true feelings about the experiment. Not surprisingly, the control group still found the experiment boring and useless. The $20 group also found it boring; they hadn’t changed their minds. Strikingly, however, the group who had been paid a single dollar now thought the experiment was useful and quite interesting (Figure 6.5).
Why should those who are paid a single dollar change their minds and the well-paid group, not? The answer, explains Festinger (1957), lies in the theory of cognitive disso- nance. It predicts that whenever there is conflict between cognitions (for example, con- flicting information about behavior, beliefs, values, and desires), people will try to reduce the conflict. Cognitive dissonance (cognitive conflict) may arise when people do things contrary to their beliefs, when they compromise principles, or when they observe people doing things they don’t expect of them.
In the Festinger and Carlsmith experiment, participants experienced dissonance because they told a lie. But if they were well paid for telling the lie, there was little dissonance because the behavior seemed justified. So those paid $20 did not change their minds about how boring the task was. But those who were paid very little money had less justification for lying; they therefore experienced more dissonance. Changing attitude is one of the easiest ways of reducing dissonance—which is what happened.
Cognitive dissonance theory contradicts the saying “The grass is greener on the other side of the fence.” When subjects are given a choice between two relatively equal options, the one they select is the one they later rank as most desirable. Why? Cognitive disso- nance theory provides an easy explanation: Whatever conflict results from having had to make an uncertain choice is quickly reduced when participants become convinced they’ve made the best choice. It should not be surprising that people who buy houses,
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CHAPTER 6Section 6.4 Cognitive Views
cars, and other objects that require major decisions immediately begin to exaggerate the positive aspects of their choices. They are simply reducing dissonance or guarding against its appearance.
There are several ways of reducing dissonance, depending on the behavior from which dissonance originated (Figure 6.6). Changing attitudes is one common method, illustrated in the experiments just described. A second method involves changing behavior. Those who stop smoking, for example, reduce dissonance created by their smoking by changing their behaviors.
Distorting information or perceptions can also reduce dissonance. When Gibbons, Egg- leston, and Benthin (1997) interviewed individuals who had stopped smoking but later started again, they found that they had significantly distorted their perception of the risks associated with smoking.
Cognitive dissonance theory has become a relatively common approach to therapy. Changes in the attitudes of patients with eating disorders or addictions can sometimes be brought about by creating cognitive dissonance to stimulate change in attitudes or behavior. For example, Smith-Machin (2009) created cognitive dissonance among groups of female undergraduates with eating disorders using discussion, exercises, and homework assignments aimed primarily at countering cultural pressures and beliefs about women’s bodies. She found significant reductions in dieting behaviors and bulimic
Neutral Enjoyable Not enjoyable -1 -0.5 0 0.5 1 1.5
Control
$20
$1
How enjoyable were the tasks?
Figure 6.5
Cognitive dissonance and “forced compliance.” In the Festinger and Carlsmith study, the group paid only $1 to lie experienced dissonance (conflict) about lying, and convinced them- selves the task was really quite enjoyable. The group paid $20 felt justified in lying, expe- rienced little dissonance, and continued to believe the experience had been boring. From Festinger, L., & Carlsmith, J. M. (1959). Cognitive consequences of forced compliance. Journal of Abnormal and Social Psychology, 58, 203–210.
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CHAPTER 6Section 6.4 Cognitive Views
symptoms among these women (bulimia and other eating disorders are discussed later in this chapter).
Achievement Motivation
The urges that propel us toward achievement are complex and not easily defined or mea- sured, although their influence can be extremely powerful. And those urges can vary widely from one individual to another. Some people have a strong drive to excel, to meet some inner standard of excellence, to do well. These people have a high need for achieve- ment (nAch); others, not so much.
McClelland and his associates’ pioneering investigations of need for achievement revealed several interesting findings (McClelland, Atkinson, Clark, & Lowell, 1953). First, and least surprising, those with the highest measured need for achievement typically achieve at
Figure 6.6
A model of cognitive dissonance. Everyone occasionally experiences conflicts between beliefs or desires and reality. There are many ways of trying to reduce cognitive dissonance.
gives rise to
cognitive dissonance– irresolvable conflict between desires and reality
w h
ic h
m o
tiv a
te s
dissonance reducing behaviors
which can take any one or more of these forms
Attitude change
(“Foxes are carnivorous—I don’t really like grapes anyway”)
Perceptual change
(“Those grapes were sour anyway”)
Behavior change
(Try a new strategy–enlist help of a nearby crow who can reach the grapes)
Attribution change
(“The grapes were too high–impossible for any fox to reach”)
Behavior that conflicts with beliefs, ideals, desires
inability to reach grapes
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CHAPTER 6Section 6.4 Cognitive Views
a higher level. But this is not always the case; just having a burning drive to achieve and suc- ceed brings no guarantees. Sometimes those more intelligent, more talented, more persistent, or luckier are the highest achievers.
Another interesting finding from this research is that children with high nAch scores tend to be moderate risk takers; those with lower scores tend to be either very low risk takers or very high risk takers. McClelland (1958) had young children play a ring-toss game where they could stand as close to the target as they wanted, and they would win prizes for accurate tosses. High need achiev- ers tended to stand a moderate distance away. But low need achievers either ensured success by standing very close to the target or ensured failure by standing very far away. When there is very little probability of success, failure carries little stigma.
There are two competing forces involved in achieve- ment behavior, explains McClelland: One is the desire to achieve success; the other is a fear of failure. What happens is that achievement-oriented behav- ior is a combined function of approach tendencies (resulting from a desire to achieve) and avoidance tendencies (resulting from fear of failure).
Attribution Theory
Why should we fear failure? Because failure might say something about what we are like: It might reflect badly on our estimates of ourselves.
We don’t all react the same way to our successes and failures, explains Weiner (2008). Some of us believe we do well or poorly because we are intelligent or not so intelligent; others think they are just lucky or unlucky. Attribution theory, which we discuss again in Chapter 10, looks at these issues.
Locus of Control Our attributions, says Weiner, depend on our locus of control—that is, on whether we are internally oriented or externally oriented. If I am internally oriented, I tend to take responsi- bility for the consequences of my own actions, attributing them either to my ability or to effort, both of which are under my control. But if I am externally oriented, I attribute suc- cess or failure to factors that are not under my control, such as the difficulty of the tasks I face or luck. Because these factors are not under personal control, the externally oriented individual does not accept responsibility for either success or failure.
There are two competing forces in achievement behavior: the desire to excel and do well, and an opposing fear of failure. Those who fear failure too much are less likely to seek out challenging and difficult undertakings. Failure, as this girl is discovering, is often uncomfortable.
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CHAPTER 6Section 6.4 Cognitive Views
Weiner also differentiates between causes that are stable and those that are unstable. Abil- ity and task difficulty are stable factors; that is, they don’t vary for a given task and a given individual. Effort, however, can be high or low; and luck can be present or absent. Thus, these are unstable variables (Figure 6.7).
Attributions and Need for Achievement One of the striking and consistent findings from attribution studies is that people who are high in need achievement are much more likely to attribute outcomes to internal fac- tors for which they have personal responsibility. They are likely to think that ability and effort—or lack thereof—are responsible for their successes and failures.
When they are successful, individuals low in measured need for achievement may attri- bute success to any of the four causal factors. That is, they might conclude they succeeded because they worked hard (effort), they are intelligent (ability), the task was exceptionally easy (difficulty), or they were just fortunate (luck).
However, when those who are low in need for achievement are not successful, they are more likely to attribute the outcome to lack of ability. They see failure as reflecting on their abilities. That, explains Dweck (2006), is because they naively believe that intelligence is fixed and unchanging, a belief that, as we saw in Chapter 5, is a myth. But even if it is a myth, this belief (the entity theory) shapes goals and efforts. Those who are convinced that intelligence is fixed often go to great lengths to convince people that they have a lot of it. Or they struggle to hide the fact that they don’t have very much. What happens in either case is that the individual avoids challenges that might expose weaknesses.
Effort U
ns ta
bl e
Internal
Causal Attributions
External
Ability
Luck
Difficulty
S ta
bl e
Figure 6.7
Four important possible attributions for success and failure. Our explanations for why we suc- ceed or fail can be internal or external; they can also invoke causes that are stable or unstable.
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CHAPTER 6Section 6.4 Cognitive Views
If, on the other hand, you believe that intelligence is malleable, that it can be improved with effort (the incremental theory), you will develop what Dweck labels a growth mind- set. Knowing that you can develop astonishing skills and talents if you work at it, you will be willing to accept challenges that would stagger others (Dweck & Grant, 2008) (Figure 6.8).
Self-Efficacy
Attribution theory presents an active view of people. We don’t simply behave; we actively evaluate our behaviors and try to make sense of them. When we fail or succeed, we try to understand the reasons why. Depending on our predispositions, our personality charac- teristics, and our previous histories, we ascribe causes to specific factors.
Basic to our attributions is what we think of our personal competence—in Bandura’s (1997) terms, our self-efficacy judgments. These are evaluations we make of our personal effectiveness in different situations. Those with high self-efficacy see themselves as capa- ble and effective.
Judgments of self-efficacy are instrumental in determining what people do; hence they’re important as motives. Under most circumstances, people don’t undertake activities that they expect to perform badly. In contrast, those with high judgments of self-efficacy are
Theory of Intelligence
Goal Orientation
Confidence in Present Ability
Behavior Pattern
Entity Theory (Intelligence
is fixed)
Performance goal (object is to avoid
negative judgments of competence, to
get good judgments)
Mastery oriented (seeks challenge; high persistence)
Helpless (avoids challenge; low persistence)
Learning goal (object is to increase
competence)
Mastery oriented (seeks challenge that fosters learning; high
persistence)
If high
If low
Incremental Theory
(Intelligence is malleable)
If high or low
Figure 6.8
Beliefs about intelligence, achievement goals, and achievement behavior. Adapted from C. S. Dweck (1986). Motivational processes affecting learning. American Psychologist, 41, 1040–1048. Copyright © American Psychological Association.
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CHAPTER 6Section 6.4 Cognitive Views
more likely to accept challenges that might dem- onstrate the validity of their judgments. Slanger and Rudestam (1997) found that level of self- efficacy judgments was one of the variables that most clearly differentiated between high and low risk takers in sports such as sky-diving, kayaking, rock climbing, and skiing.
Self-efficacy judgments determine not only what tasks people will choose, but also how much time and effort they’re willing to put in. Those who don’t see themselves as very capable are far more likely to give up rather than persist when they encounter difficulties. That’s one of the rea- sons why self-efficacy judgments are so impor- tant in schools. Williams and Williams (2010), for example, found a significant relationship between math achievement and self-efficacy in a study that looked at students in 33 different schools.
Sources of Self-Efficacy Judgments Not only does high-self efficacy contribute to high achievement, but there is a sort of reciprocal deter- minism at play in the sense that high achievement, in turn, contributes to a heightened sense of com- petence. In fact, direct experiences of success or failure (termed enactive because they result from
our own actions) are probably the most important sources of information we have about our competence.
Second, we learn about our effectiveness from vicarious (secondhand) sources—that is, by comparing our performance with that of others. That we do better or less well than peers is highly informative.
A third source of influence is persuasion. If others express faith in your abilities, if they continually urge, “Why don’t you try. I know you can do it,” you might, in the end, come to believe just a little more in your effectiveness and competence.
Finally, explains Bandura (1997), emotions can have a direct impact on your estimates of capability. Under conditions of extreme arousal, for example, you might decide that you are capable of outrunning a threatening gorilla or of swimming across a river to save a baby. And if an activity makes you feel especially good, you are more likely to conclude that you’re good at it than if it makes you feel frustrated and unhappy (Figure 6.9).
Our personal opinions of how compe- tent we are in different situations—our judgments of self-efficacy—are impor- tant in determining what tasks we choose and how much effort we put into them. High self-efficacy judgments ensure that this female will not be intimidated by the formulas behind her.
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CHAPTER 6Section 6.4 Cognitive Views
Efficacy and Expectancy-Value Theory We are not simple creatures, you and I, whose motives expose themselves easily to the probing psychologist trying to find another piece of the puzzle. No matter how over- whelmingly positive our judgments of self-efficacy and how high our expectations of suc- cess, there are other factors at play. Our choices, explain Eccles and Wigfield (2002), and our persistence and performance, are profoundly influenced by the value of the outcome we expect. And the cost of the activity, in terms of amount of effort required, sacrifices entailed, and other opportunities given up, also has to be taken into account. This is the basis of Eccles’s expectancy-value theory (Wigfield, Tonks, & Klauda, 2009).
Expectancy, in this theory, is similar to a judgment of self-efficacy; it is defined by the indi- viduals’ beliefs about how well they will do on a task. Value is a combined function of four factors: the personal importance of the task in terms of how it fits into the individual’s plans and self-image (attainment value); its intrinsic value based on the personal satisfaction the person gets from doing the task; its utility value, which has to do with what it contrib- utes to short- and long-term goals; and its cost in terms of the amount of effort required, the probability of failure, associated stress, conflicting options, and so on.
In short, it’s as though we make choices based on a sort of mental calculus. The impor- tant factors in our calculation include our expectations of success, our judgments of our
Sources of Information
Enactive
• Examples of information that might lead Sam to positive self-efficacy judgments
• He gets an A in his physics test
Vicarious
Persuasory
Emotive
• He finds out his identical twin brother has received a scholarship
• Miss Moskal tells him he could win a scholarship if he tries
• He was mildly anxious before the test but exhilarated afterwards
Figure 6.9
Sources of information that influences our judgments of personal effectiveness and competence.
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CHAPTER 6Section 6.4 Cognitive Views
effectiveness and competence (our self-efficacy), and the values and costs associated with each of the various options (Figure 6.10).
Summary of Theory
Attainment Value
Expectancy
• Choice, persistence, and achievement are directly linked to the individual’s expectancies and to the cost and value associated with the activity
• Personal beliefs about how well the individual is likely to do (self-efficacy judgments)
Value • Task-related beliefs about the value of anticipated outcomes and associated costs
• Explanation
• Importance to the person of doing well; does the option fit in with self-image?
Intrinsic Value
• How enjoyable and personally satisfying is the option?
Utility Value
• How well does each option fit in with immediate and future goals?
Cost • How much effort is required? How stressful will each option be? What am I giving up?
Components of Value
Judgment
Figure 6.10
Eccles’s expectancy-value theory of motivation, a sort of mental calculus we use to guide our choices and our efforts.
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CHAPTER 6Section 6.5 Emotions
6.5 Emotions
The mental calculus that is the basis of Eccles’s expectancy-value theory describes a cogni- tive side of human motivation. It tries to explain how we choose among different options, how we decide on goals and actions.
There is another side to human motivation. It has to do with the fact that, as Turner and Goodin (2008) explain, when we succeed in attaining a goal, we feel positive emotions; failure can lead to negative emotions. Hence emotions are a fundamental part of human motivation. And some of the physiolog- ical aspects of emotion can be detected and mea- sured. These are the changes that define arousal.
Arousal
The term arousal has both physiological and psy- chological meaning. As a physiological term, it refers to activity of the sympathetic nervous system. Physiological arousal ranges from states of very low activity such as those characteristic of sleep or deep comas (alpha, theta, or delta waves; low electrodermal response, or electrical conductiv- ity of the skin; low respiration and heart rate), to very high activity such as might be characteristic of extreme anger, fear, or panic.
As a psychological term, arousal refers to the alertness or vigilance of the organism and to the emotions that accompany physiological arousal. Thus, an individual at a very low level of arousal might be asleep; a moderately aroused individual is alert and attentive; one who is extremely aroused may be in a state of extreme emotion.
The Yerkes-Dodson Law The effectiveness of our behavior is closely tied to arousal level. At very low levels of arousal, such as when you are asleep or almost asleep, you might have trouble responding to the simplest question. But if what later awakens you is the fact that your house is on fire, you might immediately become so highly aroused that your responses would not be any more appropriate. High arousal, evident in increasing anxiety and sometimes even fear or panic, explains why some highly competent students do poorly in tense oral or written
In situations of high arousal, the body’s physiological systems prepare the individual to respond. If arousal becomes too high, panic may result and the effectiveness of behavior may drop. Some studies indicate that many soldiers under attack fail to fire their rifles. Some even run away.
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CHAPTER 6Section 6.5 Emotions
examinations. Considerable research indicates that anxiety reduces school performance (Chen, 2009).
It seems, explained Yerkes and Dodson (1908) more than a century ago, that there is a level of arousal at which behavior is most effective. Lower or higher levels of arousal are associ- ated with increasingly ineffective behavior. This observation, now known as the Yerkes- Dodson law, has been widely accepted in psychology (Landers, 2007) (Figure 6.11).
Need for Stimulation In a classic experiment, Hebb and his colleagues (Hebb, 1972; Heron, 1957) paid college stu- dents to do absolutely nothing. For as long as they wanted, they lay on a cot, getting up only to go to the bathroom and to sit on the edge of their cots at mealtime. The remainder of the time they lay down, their ears covered with U-shaped foam pillows, their eyes with translucent visors, their hands with cardboard cuffs. Overhead, a fan hummed constantly to mask any other noises. Although they could hear, see, and feel, their stimulus world was unchanging.
A p
p ro
p ri
at en
es s
o f
b eh
av io
r in
r es
p o
n se
to t
h e
en vi
ro n
m en
t
Level of arousal Low High
Optimum level of arousal
Increasing alertness
Increasing anxiety
Sleep Panic
Figure 6.11
The Yerkes-Dodson law. As arousal increases, performance becomes more effective until an optimal level is reached. Increases beyond this level lead to decreasingly effective behavior.
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CHAPTER 6Section 6.5 Emotions
This was the first of a large number of studies on sensory deprivation. For example, in a recent demonstration, the BBC (UK) arranged for six volunteers to spend 48 hours alone in totally darkened nuclear bunkers (Total Isolation, 2008). The outcome in this demonstra- tion was highly consistent with previous studies, most of which found that participants typically cannot endure the isolation for very long. In the original experiment, two days was the usual duration. In conditions of more extreme deprivation—where, for example, subjects are immersed in brine solutions in silence and darkness, floating unattended— length of stay is considerably shorter.
Among the striking findings from these studies is the observation that most subjects even- tually experience some impairment of perceptual and intellectual functioning. Tasks that are very simple before isolation become extremely difficult and sometimes impossible after prolonged sensory deprivation. In the BBC demonstration, one subject’s perfor- mance on simple memory tasks had dropped by 36 percent. In addition, many isolation participants experience emotional changes and rapidly fluctuating moods ranging from nervousness and irritability to anger or fear.
The most striking finding involves the appearance of hallucinations among some sensory deprivation subjects (Mason & Brady, 2009). These uncontrolled “apparitions,” typically visual, are mildly amusing at first and can be gotten rid of if the subject wishes. Later, however, they become more pronounced, less amusing, and quite persistent. Three of the six participants in the BBC study reported hallucinations involving objects such as snakes, zebras, and oysters; and a fourth became convinced that her sheets were soaking wet.
Sensory deprivation research strongly suggests that humans have a need for variety in sensory stimulation. If this is so, perhaps some of our otherwise unexplainable behaviors might be accounted for—behaviors such as curiosity and exploration. That we have a need for stimulation is the basis for an arousal theory of motivation.
Arousal Theory Arousal theory is premised on two assumptions (Hebb, 1972). The first, already men- tioned, is the Yerkes-Dodson law—the belief that there is an optimal level of arousal for dif- ferent behaviors and that this level varies both for different individuals and for different behaviors. For example, playing well in an intense, physical sporting activity such as foot- ball may require that players be “psyched up” (highly aroused). The same level of arousal may be a detriment in a highly cognitive task like writing an examination.
The second assumption is that individuals behave so as to maintain an optimal level of arousal. This is evident, for example, in highly arousing situations where an intensely frightened individual tries to escape or change the situation. The consequences of escap- ing from an angry mob will surely be a reduction of arousal.
The assumption is double-edged, however: It predicts not only that people behave so as to reduce arousal when it is too high, but also that they will attempt to increase arousal when it’s inappropriately low. Evidence of this is clear in sensory deprivation studies, where participants whistle, sing, talk to themselves, try desperately to engage the experimenter in conversation whenever food is brought in, and otherwise try to
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CHAPTER 6Section 6.5 Emotions
increase the amount of stimulation they’re receiving. One of the effects of sensory stim- ulation is to increase arousal.
Sources of Arousal The physiological changes that accompany arousal are brought about by activity of the autonomic nervous system, which is not ordinarily under the individual’s conscious control. We cannot easily “will” our skins to become more conductive to electricity, our hearts to beat faster, and our brain-wave activity to change.
Still, there are ways in which we can control these changes. For example, simply imagining highly arousing scenes, or seeing them depicted in pictures, films, or words, can clearly increase physiological arousal. Hence one source of arousal is internal, cognitive activity.
A second obvious source of arousal is external stimulation. The sheer amount of stimu- lation, however, may not be especially important. In the original isolation experiments there was considerable sensory stimulation, including the sound of a fan, the pressure of the cardboard cuffs, sensations relating to clothing and diffuse light, and perhaps even tastes inside the mouth and vague odors in the environment. But this stimulation was constant and unchanging, and arousal level consequently dropped dramatically. Record- ings of subjects during isolation indicate that their brain-wave functioning was more like that of the deeper stages of sleep than like that of subjects who are awake (Zubek, 1973).
The types of stimulation that appear to cause the greatest arousal are those associated with emotion. At one extreme, emotion-laden experiences can increase arousal dramati- cally, as is evident in panic situations.
In general, the most arousing stimuli are those that capture interest and attention—that is, stimuli that are surprising, novel, meaningful, ambiguous, or complex (Berlyne, 1960). These qualities of stimuli are linked with emotions such as interest and excitement; their opposites are associated with boredom and apathy. All these emotions are closely linked with motivation.
What Is an Emotion?
Emotions have presented a great deal of difficulty for psychologists. They cannot easily be defined or described; they are difficult to measure; their physiological bases don’t clearly differentiate among them. Yet they are a fundamental part of being human. In fact, it is difficult to imagine any human experience that does not involve emotions.
Emotions (or affect) have two broad dimensions. The first is intensity, which, for most emotions, can range from low to high. Thus, anger might range from annoyance to rage; disgust, from mild aversion to utter revulsion; joy, from contentment to absolute ecstasy.
Emotions vary not only in intensity, but also in terms of whether they are positive or nega- tive. Joy, love, happiness, and interest are generally positive feelings; fear, anger, rage, and disgust are more unpleasant.
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CHAPTER 6Section 6.5 Emotions
Emotion can be defined as the “feeling” or “affective” component of human behavior, where feeling describes a subjective state that can be pleasant or unpleasant, as well as intense or mild. In addition, emotion entails detectable physiological changes and is sometimes accompanied by predictable behaviors. For example, anger is generally accom- panied by increased heart and respiration rate as well as other physiological changes, and it may also be evident in changes in facial expressions, voice, and body language.
There are several thousand words referring to emotion in the English language, so it is very difficult to agree on the precise number of different emotions of which we are capable. Many psychologists have tried to summarize our emotions with lists of basic emotions. For example, Izard (2009) suggests that we can easily distinguish among six distinct emotions: sadness, anger, disgust, fear, interest, and joy/happiness. Others, such as Parrott (2004), divide basic emotions into related secondary and tertiary emotions. For example, secondary emotions related to joy include cheerfulness, zest, contentment, pride, optimism, enthrallment, and relief. And each of these secondary emotions might be described more precisely in terms of a tertiary emotion. For example, cheerfulness brings with it the possibility of many other emotions, including amusement, bliss, gaiety, glee, jolliness, joviality, delight, satisfaction, and ecstasy.
Not only have we not agreed about how many emotions we have; we cannot always agree about whether a given emotion is positive or negative. Is surprise pleasant or unpleasant? In fact, we cannot really say because emotion is not a property of stimulation, but a prop- erty of our subjective reaction to stimulation.
Emotional Expression To define an emotion is to speak about what we presume to be the subjective experience of being in that emotional state. Emotion, however, has other dimensions. Among the most important of these for human interaction is its expression. Emotions can be expressed in behavior, as, for example, when you run from an angry competitor or chase after something you want. In these examples, the motivational component of the emotion is clear. Most emotions may be seen as having approach or avoidance tendencies, although these will not always be expressed overtly.
Emotions may also be expressed verbally. Much of the richness of human conversation derives from the expression and interpretation of emotion. So, too, our books, movies, and art forms play on and with our emotions.
Emotions are expressed nonverbally as well, and they have been extensively studied as manifes- tations of facial expression. Ekman (2005) and
What emotion is this woman feeling? Look at the photo on page 192 to find out.
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CHAPTER 6Section 6.5 Emotions
others have noted that there appear to be a num- ber of emotional expressions that are innate and common to all members of our species. Raising the eyebrows is a quasi-universal expression of greeting or acknowledgment; smiling, a universal gesture of approval and friendliness.
Many emotional expressions, however, are learned and culture-specific. Klineberg (1938) examined some Chinese novels to discover how their authors describe emotional expression. It might seem strange to us that sticking out the tongue means surprise; clapping the hands indicates anxiety or disappointment; and scratching the ears shows happiness. The Chinese might be equally surprised to find us frowning when we are puzzled, chewing our lips in concentration, pounding fist in palm to signal determination or anger, and wetting our lips in anticipation.
Theories of Emotion
In addition to how we experience and express it, we know that emotion is related to activity of the autonomic nervous system, as we saw earlier in this chapter. Popular literature abounds with descriptions of physiologi- cal activity that are so meaningful, given their contexts, that the reader need not be told anything more about the nature or intensity of the emotion. “My heart beat fast/stood still/quaked/shivered/jumped/rattled in my throat/stopped.” “My hair stood on end.” “Shivers ran up my spine.” “My hands were cold/clammy/perspired/trembled/shook.”
The James-Lange Theory Early theorists made much of these physiological changes. William James (1890/1950) went so far as to say that emotion results from them, an idea being developed simul- taneously by a Danish psychologist, Lange. As a result, the theory came to be known as the James-Lange theory. In essence, it maintains that an emotion-related stimulus gives rise to certain physiological changes and that the individual perceives these physiological changes and then interprets them as an emotion. As James (1890/1950) put it, “We feel sorry because we cry . . . afraid because we tremble” (p. 1006).
The Cannon-Bard Theory Two other researchers, Cannon (1929, 1939) and Bard, objected to the James-Lange theory. They thought our awareness of physiological changes is too slow to explain how we can instantly react to emotion-laden situations. Besides, physiological changes that accom- pany different emotions don’t appear to differentiate among them; they’re not specific enough to bring about distinct emotions. Also, Cannon had demonstrated with cats that
Even when the context is clear, the emotion is not always obvious. Is this woman terrified, in pain, or ecstatic as she grabs her cotton candy?
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CHAPTER 6Section 6.5 Emotions
if he cut nerves linking the brain to those parts of the body most obviously involved in emotional reactions, the cats still behaved as though they “felt” emotion. So Cannon and Bard proposed the Cannon-Bard theory.
The Cannon-Bard theory suggests that when an individual perceives an emotion-related situation or object, the hypothalamus sends messages both to the cortex, where the emotion is felt, and to the body, where physiological reactions take place. As a result, awareness of emotion and awareness of physiological changes are independent, although they result from the same source of stimulation. It is the organism’s awareness of the emotional sig- nificance of an experience that gives rise to an emotion.
Schachter’s Two-Factor Theory It turns out that both the James-Lange and the Cannon-Bard theory are probably at least partly right. In an early study, Maranon (1924) injected human participants with epineph- rine, a compound very similar to noradrenaline, and found that while they experienced physiological reactions similar to those that accompany intense emotion, they did not feel any specific emotion.
Schachter later replicated the Maranon studies to try to clarify the relationship between physiological changes and cognitions in producing emotional states (Schachter & Singer, 1962). Participants in an experiment were told they would receive injections of a new drug that would improve their performance on a test of visual perception. Some subjects received injections of epinephrine; the others received a placebo. After the injections, they were given one of three types of information about the effects of the drug. The informed group was told what the actual effects of the drug might be and how long these effects nor- mally last; the ignorant group was told that the drug would have absolutely no side effects; and the misinformed group was told that a slight numbness and itchiness might result.
Members of each group were then assigned to one of two experimental conditions, or to a control group. The control group waited quietly for a period of time, and members were then questioned about their emotional reactions. Not surprisingly, they reported no par- ticular emotion, as had been the case in the earlier Maranon studies.
In one experimental group, the euphoria group, subjects were left to wait in a room with another individual who was introduced to them as a fellow subject. In fact this person was a confederate of the experimenters who had been instructed to perform a standardized “euphoric-manic” routine—dancing, playing basketball with crumpled pieces of paper, making little projectiles and launching them with rubber bands, playing with a hula hoop, and otherwise trying to convey the impression that this was really a lot of fun.
In the second experimental group, the anger group, subjects were left with a confederate and were asked to fill out a long and intensely personal questionnaire while waiting. It asked about the personal hygiene of every member of the subject’s family—how often they took a bath and brushed their teeth, and who had the most disagreeable body odor; subjects weren’t allowed to answer “no” or “none.” One question read: “With how many men (other than your father) has your mother had extramarital relationships? 4 and under—: 5–9—: 10 and over—.” The confederate, acting according to precise directions, became progressively angrier while completing the questionnaire, finally crumpling it up and leaving the room.
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CHAPTER 6Section 6.5 Emotions
Following this, all subjects were individually interviewed to uncover their emotional reac- tions. Results were as follows: Subjects who were uninformed or misinformed and who had received epinephrine exhibited and felt anger or euphoria, depending on the experimental condition; informed subjects and those who had received placebos typically did not.
Schachter’s explanation for these findings is the basis of his two-factor theory of emo- tion: One factor is an undifferentiated state of physiological arousal that underlies all emotions—as James had argued. The second factor is the individual’s interpretation of arousal in light of what caused it. Thus, subjects who had a logical explanation for their physiological states (the informed group) experienced no emotion. They simply labeled their physiological states according to the explanations given by the experimenter. Those who had been misinformed or not informed attributed their physiological states to emo- tions they thought they should be feeling and labeled these emotions according to the confederate’s behavior. In short, although physiological changes are clearly involved in emotional reaction, the individual’s cognitive label for the change determines the nature of the emotion (Figure 6.12).
Recent Theories Both the Cannon-Bard theory and Schachter’s two-factor theory hold that the nature and intensity of an emotion depend largely on the individual’s conscious understanding of the emotional significance of an event. These are, in a sense, attribution theories of moti- vation. Both emphasize that it is the individual’s conscious understanding of the meaning of a situation (or of the reasons for physiological arousal) that determine the emotion (Moors, 2009).
Some theorists point out, however, that not all emotional reactions require a conscious understanding of a situation. Scherer (2005), for example, argues that emotional responses can also result from unconscious cognitive activity. Someone experiencing a classically con- ditioned fear response, for example, might not always have a clear, conscious explanation for the accompanying emotion.
Other theorists have proposed that emotional responses are represented in the brain in complex, linked networks that can be activated by a wide range of related stimuli (Lewis, 2005). These emotional responses may well have been classically conditioned in the first place. The behaviorist John Watson (1930) suggested many decades ago that infants are born with three basic emotional reactions: fear, rage, and love. Each of these is elicited by specific stimuli as an unlearned reflex. For example, stroking the infant evokes emotions related to love; confining the infant might elicit rage; and fear can be brought about by loud noises. Over time, these emotions become classically conditioned to a wide range of other stimuli (see Chapter 2). What happens is that whenever an indi- vidual has an emotional experience, information about the situation, the individual’s behavior, and a variety of other related details is stored in memory and linked with other related emotions. As a result, previously neutral stimuli can come to have emo- tional significance for an individual.
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CHAPTER 6Section 6.5 Emotions
Attitude change
(“Foxes are carnivorous—I don’t really like grapes anyway”)
Behavior that conflicts with beliefs, ideals, desires
James-Lange Theory: Physiological changes are interpreted as a specific emotion. George is scared because he is trembling, his palms are sweating, and his heart it pounding.
Cannon-Bard Theory: George’s fear results from his understanding, mediated through the hypothalamus which has sent messages to his cortex as well as his autonomic nervous system, that this is a dangerous bear.
Schacter Two-Factor Theory: George is scared because he is aroused and he interprets his arousal as being caused by the danger in this situation.
Figure 6.12
Three historical explanations of emotion.
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CHAPTER 6Section 6.5 Emotions
The Dual-Pathway Model for Fear The notion that there are unconscious as well as conscious processes involved in emo- tional reactions has led to an important model of emotional processing of fear-related stimuli: the dual-pathway model. What this model says, in effect, is that there are two systems involved in fear reactions. One is unconscious and rapid; the other is slower and conscious (LeDoux, 2010).
When you see an avalanche come barreling down on you, visual and auditory stimuli race to your thalamus. From there, the information forks out into the two paths of this dual-pathway system. One path streaks to the amygdala—that part of the brain directly involved with fear and danger—and leads you to react almost instantly. Meanwhile, the other path carries information to the cortex, allowing you to interpret the situation more thoroughly (Figure 6.13). A fraction of a second later, you might decide that your initial reaction was unwarranted, that this looked like an avalanche but was just a few snowflakes on the periphery of your vision and you can relax.
Emotional Control
In a sense, our emotions control us: They make us do things. When we speak of experi- ences that have moved us, we speak of things that have evoked profound emotion. We
Increased heart rate and blood
pressure
Increased muscular tension
and reaction
Visual cortex thalamus
amygdala
Figure 6.13
The dual-pathway fear system. Signals associated with fear are first processed in the thalamus. From there, signals streak toward the amygdala, giving rise to immediate physiological and mus- cular reactions. Signals also go to the visual cortex, where they are interpreted more carefully. Now the individual, who has already started to run, might decide it is only a trained wolf.
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CHAPTER 6Section 6.5 Emotions
can as easily speak of the emotions themselves as being moving, for novelists have not yet counted all the things we do in the name of passion. Love is a motive as surely as is hun- ger; so too are hate and fear, and the vast array of more subtle, less passionate emotions.
But we are not necessarily prisoners of our emotions. Even very young infants can do things to control their emotions. When 8-month-old Jessica is frightened, she might suck her thumb, bury her face in her mother’s lap, or close her eyes and make the bad thing go away.
But we adults are wiser. We know that closing our eyes seldom makes bad thing disap- pear. We have our own ways of controlling emotions. In the first place, our successful intel- ligence encourages us to seek out situations likely to lead to pleasant emotions and avoid those with unpleasant possibilities.
The Brain and Emotions There are more extreme forms of control as well. As we saw in Chapter 2, the sometimes dramatic mood-altering effects of drugs is one; electrical or surgical brain intervention is another. For example, early studies showed that something similar to rage could be evoked in cats, dogs, primates, and other animals by stimulating appropriate areas of their brains (Flynn, 1967). These studies also showed that violent emotional reactions could be completely inhibited in these animals.
Demonstrating his confidence in such procedures, Delgado (1969) entered a bull ring armed only with a radio transmitter. The bull facing him, menacingly angry, had radio- activated electrodes implanted in his brain. He charged! But with a flourish and a flick of the switch, Delgado stopped him dead in his tracks. The bull had been turned into an apparently docile and friendly beast. What was being controlled, however, is not clear. Whether Delgado’s bull had actually become docile, whether it was just confused, or whether its motor system was paralyzed remains uncertain.
Research with humans also indicates that certain parts of the brain, especially of the limbic system, are closely involved in emotional reactions. For example, Koelsch (2010) showed that music, which can evoke very strong emotions, reliably leads to activation of virtually all limbic structures.
Odors, which often evoke strong emotions, also lead to activation of the limbic system. Schredl and associates (2009) stimulated 15 sleeping subjects during rapid-eye-movement sleep with one of two smells: hydrogen sulphide (a rotten egg smell) or phenyl ethyl alcohol (the smell of roses). Not only did these smells lead to activation of the limbic system, but they also affected the content of the subjects’ dreams. The authors suggest it might be valuable to study the effect that olfactory stimuli conditioned to pleasant reactions might have on nightmares.
Among limbic system structures that are involved in interpreting emotions and in guid- ing behavior in appropriate directions, the amygdala is especially important in processing fear reactions (Bush, Schafe, & LeDoux, 2009). There is some suggestion that impairment of amygdala functioning in individuals may be linked to psychopathology and, conse- quently, to criminal behavior. Such individuals may be unemotional, callous, and fear- less, and more prone to committing acts of violence without fear of consequences (DeLisi, Umphress, & Vaughn, 2009).
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CHAPTER 6Section 6.5 Emotions
The amygdala and other structures of the limbic system, such as the hypothalamus, are involved not only in fear reactions but also in the recogni- tion of emotional expression (Batista & Freitas- Magalhaes, 2009). Individuals with impaired limbic system functioning—as sometimes happens as a result of diseases such as Parkinsonism or alcohol- ism—may have difficulty interpreting the meaning of facial expressions (Marinkovic et al., 2009).
Not surprisingly, brain surgery can also be used to control emotional reactions. It has sometimes been used with mentally disturbed people for whom all other forms of therapy have been unsuc- cessful. The practice of removing parts of the cor- tex (for example, prefrontal lobotomy or leukotomy), once relatively common, has largely been aban- doned since the discovery that very small lesions have many of the same positive effects without the same side effects. Rosemary Kennedy, sister of President John F. Kennedy, was left permanently incapacitated after a leukotomy (Feldman, 2001).
Cognitive Control of Emotions It is possible that, at least to some degree, we are masters of our emotions and not their prisoners. In an experiment conducted by Lazarus and his associates, subjects were exposed to films of woodshop accidents (Koriat, Melkman, Averill, & Lazarus, 1972). In the films, one man lacerates the tips of his fingers, another cuts off a finger, and a third is skewered through the midsection by a plank propelled from a circular saw. He dies.
Some subjects were asked to detach themselves from events in the film; others were asked to involve themselves. In neither case were they told how to do this. Heart rate changes were recorded for every individual during presentation of the film, and reports were obtained of subjective emotional states. Significantly, subjects who were asked to detach themselves from the film had much lower emotional reaction in terms of both their heart rate and self-report. Those who were told to involve themselves experienced profound emotional reactions.
When questioned about their strategies, a majority of the involvement group said they imagined they were the person to whom the accidents were happening, or they attempted to relate the accidents to other accidents they might have witnessed or in which friends or relatives had been involved. Members of the detachment group pretended that the events had been “staged” for the filming, or paid particular attention to the technical details of the film.
In this human anatomy class, it’s likely that at least some students are using cognitive disengagement strategies to lessen the potential emotional impact of the situation.
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CHAPTER 6Section 6.6 Hunger and Sex Drive
The cognitive control of emotions is an important coping mechanism, explains Lazarus (1974, 1999). For example, a study of patients before and after surgery revealed that those who adopted detachment strategies, not wanting to know details of their surgery or symptoms of recovery or complications, experienced more rapid and smoother recoveries than patients who were more involved. Lazarus speculates that paying undue attention to possible signs of complications, or even to signs of recovery, is probably associated with more anxiety (stress) and is negatively associated with recovery. In Lazarus’s view, cogni- tive activity does a great deal to control emotional states.
Emotion is seldom a single, identifiable response to a given situation; more often it is a complex of responses. Moreover, this complex shifts continually. Anger turns into despair; grief into elation; rage into apathy; joy into sorrow; anxiety into relief. Emotions ebb and flow as we appraise our situations, our relationships with people and things, our prob- abilities of attaining or not attaining goals. The fundamental point is that we are the ones doing the appraising; the emotion resides not in the situation but in our appraisal of it. Furthermore, we exercise control over our appraisals, sometimes deliberately reducing emotional reaction, as may be the case with anger or fear, sometimes purposely enhancing it, as with love or joy.
6.6 Hunger and Sex Drive
Some of the more obvious emotions and motives have been extensively investigated—especially negative emotions such as anxiety, fear and stress and the more basic motives, including hunger and sex. In the remainder of this chapter, we look at hunger and sex; Chapter 9 looks at anxiety and fear in relation to mental health; and in Chapter 10, we look at a powerful sex-related social emotion: love.
Hunger Stimuli
Subjectively, hunger may be described as the bodily sensations that result from not eating for a period of time. Such sensations range from mild discomfort (the gentle growling of a hollow belly) to severe pain (the tortured pangs of intense hunger). Normally, death by starvation is preceded by cessation of hunger pains.
Stomach Contractions For many years most psychologists and physiologists believed that hunger results directly from the actions of an empty or nearly empty stomach. So, do we eat because the stomach is empty and it begins to contract? Early theorists thought this might be the case. Can- non and Washburn (1912) developed an ingenious test to look at this question. Washburn swallowed a balloon that was then inflated inside his stomach. The balloon was connected to a recorder so that stomach contractions could be measured. Whenever he felt a hunger pang, Washburn depressed a key to record the event.
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CHAPTER 6Section 6.6 Hunger and Sex Drive
After a while, Washburn’s stomach contracted, although he sometimes had to wait a long time for this to happen. At about the same time, he thought he felt hunger. But that piece of the puzzle did not really fit. It turns out that even people with no stomachs get hungry and that hunger persists even when neural pathways from the stomach to the brain are cut. There have now been many experiments with “gastric” balloons (Schachter, 1971). Contractions may sometimes be involved in sensations of hunger, but sometimes not, and it is likely that the duodenum (upper part of the small intestine) is even more involved.
The Role of the Brain The brain, too, plays a key role in hunger moti- vation. Satisfying hunger is highly rewarding. It leads to a pleasant state that can easily become conditioned to various situations—for example, to the taste and smell of food, to its appearance,
and to other situational factors. In fact, argues Panksepp (2010), the positive emotional states that accompany eating, in the same way as those that accompany drug use, may be very important in explaining addictions.
Using MRI recordings, Martin and associates (2010) found significantly increased brain activity in the limbic systems (medial prefrontal cortex) of subjects when they simply looked at images of food. Interestingly, obese participants displayed more brain activity than nor- mal participants both before and after a meal. This activity, the authors suggest, is closely related to food motivation.
It has been known for some time that certain parts of the hypothalamus are involved in eating behavior. Patients with tumors or other injury on the hypothalamus sometimes overeat and consequently become obese (Rowell & Faruqui, 2010). And MRI studies now indicate that the cerebellum, too, is closely involved in controlling hunger, perhaps via its connections with the hypothalamus (Zhu & Wang, 2008).
Taste and Smell Taste and smell, too, clearly contribute to food motivation, as is dramatically illustrated in studies using the black blowfly. When this fly is given a choice between a totally non- nutritive sugar substitute and a more nutritious alternative, it insists on eating the sweeter substance. And it will continue to do so until it starves to death (Dethier, 1976).
Like the blowfly, we often prefer tasty over less tasty food, regardless of nutritional value, although when we are really hungry, taste becomes less important than the imme- diate availability of food (Hoefling & Strack, 2010). The evidence suggests that as we become hungrier, we pay more attention to food cues. When participants are asked to
Hunger is a function of certain physi- ological mechanisms related to sur- vival. It’s also a function of taste, smell, appearance, and learning, and it doesn’t always relate to nutrition.
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CHAPTER 6Section 6.6 Hunger and Sex Drive
detect specific rapidly presented visual targets that are randomly inserted among other images, hungry subjects are easily distracted by food-related images (Piech, Pastorino, & Zald, 2010).
Metabolic Factors Hunger is a complex motive, tied not only to the body’s need for food and to brain activity, but also to various metabolic factors. For example, as levels of glucose (a form of sugar) in the blood drop, hunger increases; as blood glucose levels rise, there is a decline in hunger. But the relationship between blood sugar level and hunger is not quite so simple because subjects who are given sugar substitutes such as aspartame don’t subsequently eat more than subjects given sucrose, although their measured blood-glucose levels are significantly lower (Anton et al., 2010).
Many hormones and chemicals alter hunger. For example, fat cells produce leptin, a hor- mone that signals the hypothalamus to reduce appetite. Mice that lack the gene for leptin typically become obese. When they examined children’s metabolic profiles, Eriksson and associates (2010) found that leptin was the best predictor of being overweight among 8-year-old children.
Another chemical related to hunger control is cannabinoid (THC or tetrahydrocannabi- noid), the active ingredient in marijuana. There is considerable nonanecdotal evidence, both with rats and humans, that THC increases hunger and leads to overeating, even in satiated organisms. There is also evidence of differences in cannabinoid sensitiv- ity between some obese people and others of normal weight. Drugs that counter the effects of cannabinoids are occasionally successful in combating obesity, although many of these also have negative side effects (Bermudez-Silva, Viveros, McPartland, & de Fonseca, 2010).
Obesity
Unfortunately, our hunger control systems don’t always work perfectly. Overeating, termed hyperphagia, is one possibility; it sometimes results in obesity. Obesity is a global problem. Estimates are that about 15 percent of the world’s population—slightly more than 1 billion people—and more than one third of the adult U.S. population are obese (Figure 6.14). Americans now spend about $60 billion a year in efforts to lose weight, mostly on drugs, physicians, weight-reducing programs, patent weight-reducing medica- tions, and weight-reducing literature (Worldometers, 2010). An impressive 30 percent of all those who seriously attempt to lose weight will be substantially successful. Sadly, only 6 percent of these—hence fewer than 2 percent of all who try to lose weight—will maintain their reduced weights for any length of time.
A variety of factors may be at play in obesity. Metabolic factors, such as a malfunctioning pituitary gland or hypothalamus, account for a small number of cases. Genetic tenden- cies are also involved, and a handful of gene defects have now been identified as causing severe obesity (Farooqi, 2010). But the fact that incidence of obesity among children in the United States has nearly doubled since 1980 suggests that environmental factors may be
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CHAPTER 6Section 6.6 Hunger and Sex Drive
more important (Obesity Rates Continue to Climb, 2007). It is unlikely that our genes have changed significantly in just a few decades.
The most important factors that underlie obesity include the overwhelming popularity and availability of calorie-dense, high-sugar, and high-fat foods, coupled with an increas- ingly sedentary lifestyle among children. And, as Must and Anderson (2010) point out, by the time children have reached adolescence, detrimental eating and exercise habits have been repeated and reinforced so often that they are very difficult to change.
Anorexia, Bulimia, and Binge Eating Disorder
Malfunctions of our hunger control systems may be evident in overeating (hyperphagia); they may also be manifested in undereating (termed aphagia). Clinically, they may lead to one of three eating disorders: anorexia nervosa, commonly shortened to anorexia; buli- mia; and binge eating disorder.
Anorexia is classified as a mental disorder. Its symptoms include unwillingness or inabil- ity to eat and eventual emaciation. It is often characterized by a significantly distorted body image and is sometimes fatal. Its possible causes include cultural standards that glamorize thinness, family and peer pressure, and occasionally genetic factors and psy- chological issues such as low self-esteem or depression. It is most common among adoles- cent girls (Keel, Eddy, Thomas, & Schwartz, 2010).
Percentage of adult population considered obese
0 10 20 25 305 15 35 40
World
Canada
Australia
Greece
New Zealand
Mexico
United States
Figure 6.14
Percentage of adult population with a body mass index over 30, based on health estimates rather than self-reported data. Based on U.S. Bureau of the Census, 2010, Table 1306. Retrieved August 20, 2010, from http://www.census.gov/compendia/statab/2010/tables/10s1306.pdf
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CHAPTER 6Section 6.6 Hunger and Sex Drive
Literally, bulimia means “ox hunger.” It is not clear whether it is intended to mean as hungry as a bull or hungry enough to eat the entire bull. Its main char- acteristics are recurrent episodes of often secretive and guilt-ridden binge eating at least twice a week over a period of months. Binges are typically fol- lowed by compensating behaviors, including self- induced vomiting (purging) and sometimes the use of laxatives or diuretics to combat weight gain. Buli- mia is most common among adolescent girls.
Binge eating disorder is also marked by episodes of excessive compulsive eating but, unlike buli- mia, does not involve purging or other attempts to get rid of excess calories. As a result, whereas bulimics are often very thin or of normal weight, those with binge eating disorder are often obese.
There are a variety of possible therapies for anorexia, bulimia, and binge eating disor- der, including cognitive therapies (Murphy, Straebler, Cooper, & Fairburn, 2010), behavior therapies (Kroger et al., 2010), drug therapies, and sometimes even hospitalization.
Causes Interestingly, these three eating disorders often manifest at different ages. Anorexia appears earliest, peaking at around age 14, and then again around age 18. Bulimia peaks somewhat later, at around age 19, and often occurs among girls who were previously ano- rectic. Binge eating disorder appears even later, at around age 25 (Keel et al., 2010).
As we saw, various factors are related to greater risk of eating disorders, including genetic background, emotional disorders, brain injury and disease, and metabolic malfunction. But perhaps more important than any of these factors are cultural pressures stemming from what Saguy and Gruys (2010) describe as the American media’s glorification of excessive thinness. In a sense, we equate being thin with high social status; we make a moral virtue of it—an observation that is reflected in the fact that the average waist sizes of Miss America pageant winners decreased from around 26 inches in 1921 to below 24 inches by 1986 (Freese & Meland, 2002). By the same token, we associate fatness with lower status; we make of it the sins of gluttony and sloth.
These are some of the many pieces of the obesity puzzle. But we don’t yet know for sure if we have all the pieces or just how they go together.
Sexual Motivation
Nor do we completely understand sexual motivation, another powerful biological motive. Unlike hunger and thirst, sex is not necessary for the individual’s survival; but it is clearly
Obesity is a complex problem. After gastric bypass surgery for severe obe- sity, Beverley Keating, pictured here with her husband Doug and son Eldon Burke, regained half the weight she had lost. She claims she was not psy- chologically ready to be thin.
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CHAPTER 6Main Points
essential for the survival of the species. Nor is it a simple motive, easily explained by a lack or deficiency. If you do not eat, you eventually become very hungry. In contrast, the relationship between the sex drive and lack of sex is not quite so clear.
Hormonal Factors What does seem clear is that hormonal factors are closely linked to sexual urges. At puberty, when the body begins to produce the sex hormones—mainly estrogen among females and androgens (mainly testosterone) among males—sexual drive increases dra- matically. And injections of sex hormones are known to increase sexual drive (Meletis & Wood, 2009).
Cultural and Other Factors But hormones are only part of the story. In fact, when the organs that produce sex hor- mones, the ovaries in women and the testes in men, are removed, sex drive does not nec- essarily disappear. Even nonhuman primates display sexual motivation that seems to be independent of hormones. Giles (2008) summarizes a number of studies that have shown that nonhuman primates that have been castrated continue to display both sexual interest and activity. Similarly, women who have had their ovaries removed typically experience little change in sex drive.
Sexual motivation has a number of cultural and learned components as well, as is clear from looking at the sometimes dramatically different sexual behaviors of different cul- tures. Hence, aspects of sexual motivation are clearly learned. Cultural standards play an important role in determining what we find sexually arousing, even as they define sexual behaviors that are acceptable.
And for humans, perhaps one of the greatest sexual motives of all is love—a topic that science has sometimes found awkward. It is a piece of the puzzle that we examine in Chapter 10.
Main Points 1. What Is Motivation? Motivation deals with the conscious and unconscious
forces that instigate, direct, and control our behavior. 2. Behavioristic and Physiological Approaches: Instincts provide little explanation
for human behavior, but the hedonistic principle (we seek pleasure and try to avoid pain) and need-drive theory support the behavioristic notion that satisfy- ing needs is reinforcing. Most important is the incentive value of goals, linked with our ability to imagine and anticipate the consequences of our actions.
3. Maslow’s Hierarchy: Maslow suggests that we are driven by low-level basic (deficiency) needs and higher-level (growth) needs, hierarchically arranged so that higher-level needs are not attended to until lower-level needs have been satisfied. The highest human need is the need for self-actualization.
4. Cognitive Views: Cognitive dissonance theory says that conflict between cogni- tions (between values and behavior, for example) leads to behavior designed to
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CHAPTER 6Main Points
reduce the conflict. Achievement motivation theory explains how need to achieve and fear of failure interact. Attribution theory looks at how internal or external orientations color our explanations for success and failure. Attributions are also driven by our self-efficacy judgments. Expectancy-value theory accounts for choices on the basis of a mental calculus that factors in the value of the goals for which we strive and the costs associated with obtaining them.
5. Emotions: Emotions are motives; we are driven toward positive emotions and away from negative emotions. Intensity of emotions is reflected in physiological arousal. Our need for stimulation and our efforts to combat boredom reflect the principle (Yerkes-Dodson law) that there is an optimal level of arousal for most tasks. Intensity of emotions is reflected in arousal level; the nature of the emotion has to do with cognitive interpretation. The James-Lange theory of emotion says you feel an emotion because of your physiological reactions; the Cannon-Bard theory says, No, emotion and physiological reaction are separate; you feel an emotion because of your cognitive interpretation; Schachter’s two-factor theory says the physiological reaction is basic to the emotion, but its nature is deter- mined by the cognitive attribution the individual makes. The limbic system is closely involved in emotions.
6. Hunger and Sex Drive: Hunger control has to do with stomach sensations, changes in blood sugar level, hormonal and chemical signals (many of which affect the limbic system and especially the thalamus), and a host of learned fac- tors associated with the taste, smell, and appearance of food and with cultural values associated with food and with body appearance. Malfunctions of hunger control systems can result in obesity or in eating disorders such as anorexia, bulimia, or binge eating disorder. Sex drive is related to hormonal, cultural, and other factors, sometimes including love.
Study Terms
androgens
anorexia nervosa
aphagia
arousal
arousal theory
attribution theory
binge eating disorder
bulimia
cognitive dissonance
drive
drive reduction
electrodermal response
emotions
entity theory
estrogen
expectancy-value theory
hyperphagia
incentive motivation
incremental theory
instincts
locus of control
metaneeds
motivation
need for achievement (nAch)
nominal fallacy
obesity
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CHAPTER 6Main Points
physiological needs
psychological hedonism
psychological needs
self-actualization
self-efficacy
Yerkes-Dodson law
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7
Human Development
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • What are some of the details of human biological beginnings? • How do chromosomes and genes determine characteristics such as sex and eye color? • How are common sex-linked defects transmitted? • What is the nature-nurture controversy? • What are the principal developmental characteristics of infancy? • How does Piaget describe development during childhood? • What are Marcia’s four possibilities with regard to identity formation in adolescence? • How does Erikson’s psychosocial theory describe the adult years?
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CHAPTER 7Human Development
Breast feeding should not be
attempted by fathers with hairy chests,
since they can make the baby sneeze and
give it wind. —Mike Harding, The Armchair
Anarchist’s Almanac
Chapter Outline
7.1 The Beginning: Genetics and Prenatal Development
Chromosomes and Genes Genetic Defects Heredity and Environment Prenatal Development
7.2 Infants Physical and Motor Development in Infancy Perception in the Newborn Cognitive Development in Infancy Social-Emotional Development in Infancy
7.3 Children Cognitive Development in Childhood:
Piaget’s Theory Children’s Social-Emotional Development
7.4 Adolescents Physical and Sexual Changes Adolescent Egocentrism Identity Formation
7.5 Adults Erikson’s Stages of Adulthood
Where I come from, even men with hairless chests seldom attempt this feat; it is left to women. Which does not guarantee that the infant will not have wind.
In any case, fathers were never overly involved in my neck of the woods. They usually had some other place to be or something else to do. For sure, they were almost never present at a birth unless it surprised everyone.
In some quarters, things haven’t changed all that much. As George H. Davies put it, “What’s all this fuss about fathers being present at the birth of their children? The way events are shaping, they’ll be lucky to be present at the conception.”
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
7.1 The Beginning: Genetics and Prenatal Development
Things have changed drastically in North America in recent decades: Now fathers are often present at the births of their children. But George H. Davies may still be at least partly right because with today’s medical technology, the dad does not necessarily have to be there at the beginning. His role can be taken over by artificial insemination, in which a physician introduces sperm into the uterus, or by in vitro fertilization, where a previ- ously fertilized egg is used.
But no matter the procedure, in the very beginning, we are a zygote—a fertilized egg. Most mature human females produce a single ovum (egg cell) once every 28 days. Some women occasionally produce more than one egg at a time, making multiple births pos- sible. Multiple births also occur if a single egg separates after fertilization. Where two eggs are involved, the resulting twins will be fraternal, or dizygotic, since they come from two zygotes. Where a single egg is involved, the twins will be identical or monozygotic.
A mature human male normally produces several billion sperm cells every month. These are among the smallest cells in the human body, but they have an extraordinarily long tail. In contrast, the ovum is the largest cell in the human body at about 0.15 millimeter in diameter, which is about half the diameter of the period that ends this sentence. Under the right circumstances, an egg cell can be seen with the naked eye.
The egg and sperm cell are the immediate origins of life. After activities beyond the scope of this book, the sperm, competing against 300 or 400 million other sperm, undertakes an immense journey across the colossal expanse of the uterus and up a gigantic fallopian tube. It uses its whiplike tail to swim against horrendous currents, determined to be the first to reach the ovum. And if it gets that far, it will be one of only 300 or 400 that have done so. (Figure the odds! About one in a million of ever reaching the ovum; and about half the surviving sperm have gone up the wrong tube! See Figure 7.1.)
But the game is not yet won, even if there happens to be an egg here, roughly halfway up one of the fallopian tubes (remember that only one is released about every 28 days). The battered and exhausted sperm must now butt its head against the egg’s tough outer shell to penetrate it. And if it succeeds, it will be the only one to do so because the egg will immediately release an enzyme that hardens the shell and makes it virtually impen- etrable. All the other sperm that have survived the journey are now doomed.
In the next stage of this incredible drama, the very matter of which the sperm is composed fuses with matter inside the egg and we have conception (the formation of a zygote, a fertilized egg). Now slow-moving currents carry the zygote back down the fallopian tube into the uterus, where it attaches itself to the uterine wall. All of this takes place within 7 days. During the next short while, the placenta and umbilical cord form, the placenta being a flat membrane that links mother and embryo. The umbilical cord is a tubular affair perhaps 18 inches in length, containing two veins and an artery and linked to the placenta at one end and to what will eventually be the child’s navel at the other. There are no nerves in the umbilical cord, and the child’s developing nervous system is never linked with the mother’s (Figure 7.2).
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
Some 266 days after conception (280 days following the onset of the last menstrual period, which is roughly 9 calendar or 10 lunar months, each lunar month consisting of 28 days), barring accident or design to the contrary, a child will be born. And this child will be dif- ferent from any other that might have been born instead. Why?
Chromosomes and Genes
The piece of the puzzle that answers this question involves a strange game of chance. You see, every cell in both the father’s and the mother’s body contains 23 identical pairs of chromosomes. These contain genes, which are the units of heredity (Figure 7.3). But as sex cells mature, the 23 pairs of chromosomes split up so that offspring receive half their genetic material from each parent. And in this game of chance, the division of genes is random: Genetic material crosses from one chromosome to another to yield an absolutely mind-boggling number of possible combinations. In the end, the genetic hand that fate has dealt you is only one of some 60 or more trillion different possibilities.
Figure 7.1
The odds of these sperm cells making it this far are about one in a million. And in the end, only one, if any at all, will succeed in penetrating the ovum’s tough outer shell and fertilizing it.
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
Male or Female That you are male or female depends on one particular card in your hand, the sex chromo- some card. You inherit 23 chromosomes from your mother, and 23 from your father; and among each of these 23 chromosomes is a sex chromosome, imaginatively labeled X or Y. The mother produces only the X variety; the father produces either one. Thus the resulting pair of sex chromosomes can be of two varieties: XX or XY. If, at the time of conception, the sperm bears a Y chromosome (is XY), the offspring will be male; if it contains an X chromosome (is XX), the offspring will be female (Figure 7.4).
The Genetic Code That you are male or female is a chance biological occurrence determined by that one tiny pair of chromosomes. It, along with the other 22 pairs of chromosomes you have
fallopian tubes
ovaries
mature ovum
developing follicles
mature follicle
sperm
uterus
A
B
C
Figure 7.2
The beginning. At (A), several hundred million sperm cells have entered the vagina. Some will succeed in swimming across the uterus. Perhaps one in a million will reach the egg, and one may fertilize it (B). The fertilized egg drifts down the fallopian tube, dividing and forming new cells as it goes. About 7 or 8 days after fertilization, it implants itself in the uterine wall (C).
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
inherited, determines your very own, absolutely unique genetic code. This code takes the form of arrangements of deoxyribonucleic acid (DNA) that make up these chromo- somes (Figure 7.5). Genes can be viewed as segments of chromosomes, arranged in rows (somewhat like beads on a string). They are also arranged in pairs in terms of their rela-
Figure 7.3
A photograph of the 23 pairs of chromosomes in a human cell.
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
tive position on the chromosomes. Corresponding genes on corresponding (homologous) chromosomes are termed alleles.
Dominance and Recessiveness Genes are what determine whether you will have dark or light hair, fair or dark skin, blue or brown eyes. In the simplest scenario, each allele—that is, each member of a cor- responding pair of genes—will be either a dominant gene or a recessive gene. For exam- ple, the gene for brown eyes is dominant and the one for blue eyes, recessive. This means that if an individual inherits a gene for blue eyes from one parent and a gene for brown eyes from the other, that individual will have brown eyes. It also means that all individu- als with blue eyes have two recessive genes for eye color. Individuals with brown eyes, however, might have two dominant genes (both for brown eyes) or one dominant gene (for brown eyes) and one recessive gene (for blue eyes). Figure 7.6 illustrates simple dominance and recessiveness with respect to tongue-rolling ability, which is associated with a dominant gene.
X
Y
X-bearing sperm
Y-bearing sperm
X-bearing egg XX (female zygote)
X-bearing egg XY (male zygote)
X XX
X XY
X XX
X XY
Figure 7.4
Only the male sex cell can contain either an X or a Y sex chromosome; the ovum contains only the X—a fact of which Henry VIII was ignorant as he kept beheading his wives for failing to give him sons.
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
Figure 7.5
DNA molecules are arranged in sequences of pairs in a spiraling, double-helix structure. Genes, the units of heredity, can be thought of as locations or addresses on a segment of DNA.
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
Your genetic inheritance defines your genotype; the observable characteristics that your genotype produces are your phenotype. For example, if you have blue eyes, that is your phenotype; and because this manifested characteristic depends on the presence of two recessive genes, we can infer your genotype with respect to eye color. But if your eyes are brown, we can only guess at your genotype without DNA analysis.
If all human characteristics were determined by the dominance or recessiveness of genes, human genetics would be considerably simpler. They are not. Many traits are a function of an indefinite number of genes (polygenetic determination). And to make mat- ters even more complicated, dominance of single genes is not always complete; some- times it is only partial. What this means is that a child can have green eyes, or even one blue eye and one brown eye.
So although it is generally possible to predict the gross characteristics of animals that are deliberately bred for certain qualities, there are often “throwbacks”—offspring possessing unexpected characteristics. Some of these may be due to mutations—rare, random events that can be caused by radiation, drugs, or other unknown factors. Thus, it is possible, though improbable, for brown-eyed parents to produce a blue- eyed child.
none can 2 cannot 2 can
all can
2 can 2 cannot
1 cannot 3 can
all can
all can all can all can
Cannot Can Can C
an n
o t
C an
C an
Mother F
at h
er
Phenotype Genotype
P he
no ty
pe G
en ot
yp e Possible Offspring
recessive (absence of tongue roll)
dominant (tongue rolling ability)
Figure 7.6
Can you roll your tongue as shown? If you can, do you think at least one of your parents also can?
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
Genetic Defects
The importance of determining genotype lies in the possibility of predicting the likely characteristics of offspring. Such knowledge is especially important in the case of genetically determined defects.
Sex-Linked Defects Hemophilia (bleeder’s disease), hereditary bald- ness, night blindness, and color blindness are four common sex-linked defects. The genes that give rise to these defects are found on the X sex chro- mosome. Recall that a male has a single X chro- mosome and a Y chromosome; a female has two X chromosomes. Because the Y chromosome does not have genetic material corresponding to these defects, it cannot counteract them with a normal, dominant gene. So if a male inherits a single reces- sive gene for baldness, that male will eventually be bald (should he live so long). Because the Y chro- mosome can only have been inherited from the father (only males produce Y chromosomes), bald- ness is inherited from the mother, just as hemo- philia, night blindness, and color blindness often are. The reason there are so few bald, hemophiliac, or color-blind women is that there is a very high probability that one of their X chromosomes will contain the dominant gene that will counteract the recessive gene for these defects.
Non-Sex-Linked Defects Genetic abnormalities not linked to genes on the sex chromosomes are said to be non-sex- linked. These abnormalities are seldom associated with dominant genes; and if they are, they don’t result in early death, impotence, or severe early illness. If they were, they would not be passed on to the next generation and would soon be completely eradicated from the human genetic pool. This, of course, is not the case for abnormalities that are linked to recessive genes, since these genes will be carried by many individuals who don’t manifest the abnormality.
Chromosomal Disorders In addition to gene-linked defects and diseases, there are a number of abnormalities caused by defects in chromosomes rather than by specific genes. Some of these involve abnormal chromosomes; others are due to the presence of extra chromosomes or the absence of chromosomes (Table 7.1).
Queen Victoria, Prince Albert, and some of their 9 children. Queen Victo- ria carried the recessive gene for hemo- philia, as did two of her daughters. In the next generation, 3 of 7 male descen- dants suffered from hemophilia and 4 of 6 females carried the gene but were healthy. These 4 females produced only 3 males who were known to be healthy, and 6 who were hemophiliac.
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
Table 7.1 Some Genetic Defects and Chromosomal Disorders
Defects Some Characteristics
Genetic Defects
Huntington’s disease • Linked to a dominant gene but not manifested until age 30 or more • Progressive neurological disorder that is usually fatal
Sickle-cell anemia • Linked to a recessive gene • Can lead to serious illness with lack of oxygen
Phenylketonuria (PKU) • Linked to recessive genes • Associated with early-onset severe retardation • Easily detectable at birth and treatable through dietary means
Tay-Sachs disease • Linked to a recessive gene • An enzyme disorder usually fatal early in life
Muscular dystrophy • Some forms linked with recessive genes • Degenerative muscular disorder
Neural tube defects • Genetically linked spinal tube defects (spina bifida or anencephaly) • Detectable with AFP test*
Diabetes mellitus • Some forms linked with recessive gene • An insulin deficiency disease, often controllable
Chromosomal Disorders
Down syndrome (trisomy 21) • Often associated with nondisjunction of the 21st chromosome, so that offspring has 3 (hence trisomy 21) • Common cause of mental retardation, often linked with parental (especially maternal) age
Fragile X syndrome • Linked with an abnormally compressed or broken X chromosome • Highly common cause of male mental retardation, often not manifested until adolescence
Turner syndrome • Female disorder linked with absence of an X chromosome (XO) • Symptoms sometimes alleviated through injections of estrogen at puberty
Klinefelter syndrome • Male child with an extra X chromosome (XXY) • Treatment often involves injections of testosterone
Supermale syndrome • Male child with extra Y chromosome (XYY) • Tentative but poorly established linked with criminality
The alpha-fetoprotein (AFP) test looks at the presence of AFP in the pregnant woman’s blood. Elevated levels indicate
higher risk of one of several birth defects.
Modifying Genetic Defects Selective breeding is clearly one way of modifying and controlling genetic defects: Ani- mal husbandry and agriculture have long practiced it. Through interbreeding of vari- ous mutants, agriculture has given us the large-breasted turkey, the hairless peach, the
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CHAPTER 7Section 7.1 The Beginning: Genetics and Prenatal Development
seedless orange, the speedy thoroughbred, the pink grapefruit, and the huge tomato with the long shelf life.
We correct our genetic defects in less ethically sensitive ways. We wear glasses for near- sightedness and astigmatism, both of which are sometimes hereditary; we cover baldness with hair transplants, wigs, and shoe polish; we alter the PKU infant’s diet; and we estab- lish educational institutions for those with physical and mental challenges.
Heredity and Environment
Genetics alone does not complete this part of the human puzzle. Take yourself as a case in point. Blue or yellow eyes; straight, kinky, or curly hair; peach, alabaster, copper, or ebony skin; straight, hooked, curved, flat, small, or large nose; tall or short; thin or wide; freck- led, speckled, mottled, striped, or plain: Your physical systems, we assume, correspond relatively closely to your genetic code.
Look at yourself again. Your language: French, English, German, Swahili, Barnbuti, or Texan; your talents: musical, poetic, manual, verbal, athletic, numerical, or hidden; your values; your political beliefs; your self. Clearly, what you have become is inextricably bound with the experiences you have had.
As we saw in Chapter 5, psychology has long debated the relative contributions of hered- ity and environment—the nature-nurture controversy. Is intelligence inherited? Mental disorders? Personality traits?
Extremists have often adopted one point of view or the other. But now, virtually nobody believes exclusively in genetics or the environment. It is clear that both are involved in determining developmental outcomes. Even physical characteristics such as height and weight are susceptible to environment influences such as nutrition and exercise. The important question is no longer whether heredity is the most potent force in develop- ment, or whether the honor should go to the environment; rather, the question is how they interact in the course of human development.
Prenatal Development
That development, as we saw, begins with the zygote, the fertilized egg. And for the next 266 days, the course of prenatal development is more predictable than it is for any other stage of development (Figure 7.7). Thus, the average newborn infant will more closely resemble all other newborn infants than the average 12-year-old will resemble other 12-year-olds.
The actual process of birth presents more of a medical than a psychological phenomenon, although it can sometimes have pronounced effects on the later development of the child. On occasion, brain damage can result from oxygen deprivation during birth, or as a conse- quence of prematurity. Brain damage may be evident in intellectual or motor impairment of varying severity.
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CHAPTER 7Section 7.2 Infants
7.2 Infants
It is sometimes disquieting to learn about all the defects and diseases to which we are potential heirs. The truth is that in spite of all that can go wrong, most often nothing does and in the end another normal, happy infant is born.
Physical and Motor Development in Infancy
This infant, if an average male, will be perhaps one-quarter to one-half inch taller, and about a pound heavier. There are, of course, many individual exceptions.
Human development is typically divided into various stages (Table 7.2): Infancy, which lasts until age 2, is the first of these.
Lunar Month
Weight Length Characteristics
1 Negligible Negligible Cell differentation into those that will be bones, nerves, or other cells
5 11 oz. (308 g)
10 in. (25 cm)
Fetal movement (quickening) appears
6 20 oz. (560 g)
12 in. (30 cm)
Heartbeat clearly discernible; eyelids present
7 2.6 lb. (1.2 kg)
15 in. (37.5 cm)
8 4 lb. (1.8 kg)
16 in. (40 cm)
Development is now largely a matter of increasing weight and length
9 4.7 lb. (2.1 kg)
17.5 in. (44 cm)
10 7.5 lb. (3.4 kg)
20 in. (50 cm)
4 4 oz. (112 g)
6 in. (15 cm)
2 2/3 oz. (19 g)
1½–2 in. (3.75–5 cm)
Leg buds and external genitalia appearing
3 7/8 oz. (24.5 g)
3 in. (7.5 cm)
Bones forming, organs differentiated. If aborted, will make primitive breathing movements.
Figure 7.7
Prenatal development by lunar month (weight and length are approximate).
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CHAPTER 7Section 7.2 Infants
Table 7.2 Major Stages in Human Development
Stages and Substages Time Span
Prenatal Conception to birth
Neonatal Approximately first 2 weeks of life
Infancy Until age 2
Childhood Early Childhood Middle Childhood
2 to 11–12 years 2 to 6–7 years 6–7 to 11–12 years
Adolescence 11–12 to 19–20 years
Adulthood Early Adulthood Middle Adulthood Late Adulthood
20 to the end 20 to 40–45 40–45 to 65–70 65–70 to the end
One of the important developmental outcomes of infancy involves changes in motor abili- ties. Although newborn infants are almost unique among the earth’s animal species in their inability to locomote within a short time of birth, they are among the few that eventually learn to walk on two legs. Other nonhuman primates who are capable of this same feat are usually more at home on all fours than on two; and the kangaroo, which does move on two legs, cannot run or even walk very well on those two legs, but must instead resort to hopping.
But the newborn does not hop, does not even crawl. In fact, the newborn’s first movements are largely uncoordinated and purposeless. But these movements are a way of exercising and developing control over muscle systems. Gradually, they become more purposeful. At first the infant can only stare at an interesting object, waving hands and arms wildly, clearly excited but incapable of coordinating action with intention. Learning to reach and grasp, like learning to walk, is not an easy matter.
In time, infants do learn to walk—and eventually, like the kangaroo, to hop. But first they go through a relatively predictable sequence of motor achievements: learn to lift the head, to turn over on the back, to direct hand movements, to sit, to crawl, to stand, to walk, and finally, to hop.
Perception in the Newborn
For a long time, psychologists believed William James’s (1890/1950) claim that the infant’s world is “one great blooming, buzzing, confusion,” that, in particular, vision and hearing are so poorly developed as to be virtually useless. We now know that is not quite true. Infants are sensitive to light almost immediately after birth and are capable of visually following moving objects within a few days. When shown blurred or clear images of human faces, they show preference for the clear face (Berger, Donnadieu, Meary, Kandel, & Mazens, 2010). With respect to hearing, evidence suggests that, unlike the young of many species that are deaf at birth (dogs and cats, for example), the neonate is sensitive to a wide range of sounds and can also locate the direction of sounds (Volpe, 2008).
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CHAPTER 7Section 7.2 Infants
The smell system, too, is functional in newborns. When presented with unpleasant odors, newborns turn away (Porter & Rieser, 2005). In contrast, the smell of their own mother’s milk, but not that of other mothers, has a calming effect on them (Nishitani et al., 2009).
The taste, system, too, seems to be relatively well developed in newborns. In fact, it seems that they can learn about different tastes even before they’re born. Mennella, Jagnow, and Beauchamp (2001) had a group of pregnant mothers drink carrot juice during pregnancy. Their infants later showed stronger preference for carrot-flavored cereal than did other infants whose mothers had not drunk carrot juice while pregnant.
Cognitive Development in Infancy
So even before birth, newborns begin to learn, as is evident in their recognition of flavors to which their mothers have been exposed. But the fact is, they aren’t born with a great store of knowledge and ideas and opinions. For the first three months of their infants’ lives, Super and Harkness (1998) tell us, Kipsigis mothers in rural Kenya refer to them as monkeys; only later do they call them children.
Why? One plausible answer is that the newborn is much like a little monkey: It can respond to a small range of stimuli, it can cry and vomit, and it is heir to a handful of survival- related reflexes such as sucking and rooting. But it would surely die if its environment did not include adults devoted to its survival. There is much that the infant needs to learn, much with which it must become familiar, before it can stand on its own two feet—not only physically, but also cognitively.
We know that infants are born with an impressive array of cognitive tools—tools that will eventually allow them to know and understand things of which they cannot yet even dream. They can look and see; they can hear; they can smell and taste. And more impressive than anything else, they have an astonishing brain. In fact, they are remark- ably ready to become familiar with all there is out there.
That infants begin to learn before and immedi- ately after birth seems clear. As an example, Lipsitt (1971) conditioned infants’ rooting reflex by strok- ing their cheeks when a tone sounded. (Rooting is the infant’s reflexive head turning when the cheek or corner of the mouth is stimulated—an impor- tant reflex for finding nipples.) If they turned in the appropriate direction, they were reinforced by being allowed to suck briefly on a nipple. Within a half-hour of training, newborns who had ini- tially turned in response to the tone an average of 25 percent of the time now turned 75 percent of the time. Perhaps even more striking, when a different tone was introduced and the newborns were not reinforced for turning in response to the second tone but were still reinforced for the first
Infants are born with an impressive array of cognitive tools. This tyke is learning more than just one thing at a time.
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CHAPTER 7Section 7.2 Infants
tone, they continued to respond to the second tone only 25 percent of the time. Thus, newborns can not only be conditioned, but they can also dis- criminate between different sounds.
Cognition and Language Development Discriminating the sounds of a language is essen- tial for one of the most formidable and important of all cognitive tasks: learning to communicate with language. And, as we saw in Chapter 2, lan- guage is basic to thinking, to creating and partici- pating in cultures, and to communicating.
But communication and language are not quite synonymous. A dog that walks to its empty dish, looks its master in the eye, and begins to growl is communicating but is not using language. Lan-
guage is the use of arbitrary sounds or symbols in a purposeful way to convey meaning; communication is simply the transmission of a message.
The infant’s first communication system is not language but a complex system of sounds and gestures. To master this communication system, the infant needs to learn five things: turn taking, the use of gestures, sound discrimination, sound production, and words. All of these are basic to adult conversation. These accomplishments are part of the prespeech stage of language learning.
At around age 1, though sometimes much earlier or later, the first word appears. In all cultures, the first words tend to be nouns—simple names for common, everyday objects (Salerni, Assanelli, D’Odorico, & Rossi, 2007). Often, the earliest consistent sound made by an infant is not a recognizable word but has a clear meaning. Elizabeth, at a startlingly young age, repeatedly said “buh”—an expression that her parents eventually realized meant “light” or “turn the light on and off and on and off and on and off . . .” These sorts of consistent sounds are labeled protowords.
Holophrases are similar to protowords except that they are real words rather than just sounds. Holophrases are words or expressions that are sentencelike in that they contain a variety of sometimes complex meanings. Holophrases usually appear by the age of 12 months. They often express meanings that an adult could not easily communicate in less than an entire sentence. For example, the holophrase “up,’’ uttered in an unmistakably imperious tone by 1-year-old Nathan, means “Pick me up right now and sing me a song or else I may do something really annoying.”
By the age of 18 months, most infants have begun to join modifiers to nouns and pronouns to make two-word sentences. At this stage, speech is still highly telegraphic; complex meanings are squeezed into simple, and sometimes grammatically incorrect, two-word utterances. For example, the sentence “Mummy gone’’ may mean something as complex as “my dear mother is currently on a business trip in Chicago.’’
The prespeech stage of language learn- ing spans most of the first year. It entails learning to take turns, to use gestures, to discriminate among dif- ferent sounds, to produce sounds, and eventually to produce words. A good set of wireless headphones with clev- erly designed lessons might also help.
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CHAPTER 7Section 7.2 Infants
During this stage, there is ordinarily a tremendous spurt in vocabulary, common to all cul- tures. Whereas learning the first 100 or so words can take several months, the next hundred might be learned in just a few weeks (Yu, 2008). This type of learning is called fast mapping.
Note that in all early stages of language learning, children’s passive vocabulary is much larger than their active vocabulary. That is, they understand far more words than they actually use in their speech.
Multiple-word sentences typically appear by the age of 2 to 2½. Although early preschool speech is still often telegraphic, it includes complex grammatical variations to express dif- ferent meanings. By the late preschool years, it has become adultlike.
Although average ages are assigned to each of these developments, they are simply approximations. Here, as in all areas of human development, it is normal for some to dis- play a behavior earlier or later. An average is not an expression of normality; it is simply a point around which observations are distributed. (See Table 7.3 for a summary of early language development.)
Table 7.3 Sequence of Infant Language Development
Developmental Stage Main Accomplishments Sample Utterances
Prespeech (before age 1) Turn taking Using gestures such as pointing Discriminating and producing
sounds
“Waaaaaa . . .” “Gooogoooogoooogaaahgaah”
First words (around age 1) Protowords (nonwords with consistent meaning)
Holophrases (single words with sentence-like meanings)
“Bulla,” meaning all umbrella-like things, including rhubarb leaves
“Mama,” meaning “Would you please come here mother and bring the milk with you . . .”
Two-word sentences (around age 18 months)
Vocabulary spurt Fast mapping (one-exposure
learning)
“More milk” “Pretty horsie”
Multiple-word sentences (by age 2 to 2½)
Longer sentences; more gram- matical variation; increasingly correct use of word classes
“Read again book” “I no can play” “I runned fast”
Social-Emotional Development in Infancy
Average vocabulary size at different ages is relatively easily calculated; uncovering aver- age social and emotional characteristics is more challenging.
Erikson’s Stages Erik Erikson (1963; 1968) describes eight major stages in human development over the lifespan. Each of these stages is identified by a basic conflict brought about by the need
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CHAPTER 7Section 7.2 Infants
to adapt to the social environment—hence it is a theory of psychosocial development. And at each level, new competencies are required of the indi- vidual. The first two of these stages span infancy (all eight stages are summarized in Figure 7.13).
Trust Versus Mistrust The first task for the infant, Erikson explains, is learning to trust this bewilder- ing and often frightening world—in the face of a strong tendency not to trust because everything is so strange and unfamiliar. The most important per- son in the infant’s life at this stage is the principal caregiver. If that person is warm and loving, the infant soon learns that the world is a safe, warm, and predictable place. But if the caregiver is cold and rejecting, the child may grow up to be wary and anxious.
Autonomy Versus Shame and Doubt At first, infants cannot intend to carry out an action and then do so. They have to learn to coordinate and control activities according to intentions. As they begin to realize that they can intend and accomplish things, they develop a growing sense of auton- omy. But always, there is the tendency to go back to a safer period, back to the comfort and security that marked the end of the previous period. Suc- cessful resolution of this conflict depends largely on caregivers giving the child opportunities to explore and to be autonomous.
Infant States Clearly, however, not all infants develop in the same way and at the same pace. Even very early in life, we are sometimes very different from one
another in our typical behaviors and reactions. These early differences might foreshadow differences among adults.
The most common infant states are described as regular sleep, disturbed sleep, drowsiness, alert activity (alert and actively responding to stimuli), alert inactivity (alert, examining environment, but inactive), and crying (Wolff, 1966).
Infants vary tremendously in the amount of time they spend in each state. For example, in a study of six infants, Brown (1964) found that although the babies spent approximately one third of their time sleeping, one infant slept 56 percent of the time, and another 22 percent of the time. One infant cried 35 percent of the time; another, 17 percent of the time. One was alert 40 percent of the time; another, 10 percent of the time (Figure 7.8).
Sleep is the most common newborn state, occupying about two thirds of the day. Happily, crying is the least common state.
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CHAPTER 7Section 7.2 Infants
Infant-Caregiver Interaction To understand what it is like to be a child, it is essential to know which child, when, and where. We have to be aware of children’s contexts and of how these contexts have changed and continue to change. We also need to know something of the ethnic, cul- tural, social, and political realities in the child’s life. Perhaps most important, to under- stand the lives of infants, we need to ask about interactions in the family, because the family usually defines the most important aspects of the child’s physical and social context.
Traditionally, the emphasis has been on dyadic interactions (interactions involving two individuals)—especially the mother-infant dyad. Father-infant and infant-sibling interac- tions also need to be taken into account. More complex interactions are concerned with how infants affect parents and change the family, and how these changes in turn affect the infant. The contexts in which the family functions—social, political, economic, religious, and philosophical—are all important influences in shaping the child.
Infant Temperament Parental characteristics, such as patience or irritability, influence how parents interact with their children; so, too, do infant characteristics.
The infant’s characteristic ways of behaving define temperament, a term that is some- what different from personality. Personality indicates a degree of learning and experience
Infant
P er
ce n
ta g
e o
f ti
m e
sp en
t sl
ee p
in g
1 2 3 4 5 6
0
10
20
30
40
50
60
Figure 7.8
Brown observed 6 infants for 1 hour about an hour after feeding, during the first week after birth. Shown here are the tremendous variations in the amount of time each spent sleeping. (Based on data from J. L. Brown, 1964.)
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CHAPTER 7Section 7.2 Infants
that infants have not yet had; it is used to describe identifying traits of older children and adults. Temperament, on the other hand, implies an inherited predisposition to act and be a certain way. For example, some infants are habitually active, others quieter; some readily approach strangers, others hide behind their mothers; some are generally happy, others less so.
After looking at the typical behaviors of a large group of infants, Thomas and Chess (1977) found that certain infants seem to have remarkably similar patterns of characteristics. One group, the difficult infants, is characterized by irregularity in such things as eating, sleeping, and toilet functions; withdrawal from unfamiliar situations; slow adaptation to change; and intense and often negative moods.
In contrast, easy infants are characterized by regularity in eating, sleeping, and toileting; high approach tendencies in novel situations; high adaptability to change; and a prepon- derance of positive moods as well as low or moderate intensity of reaction.
Slow-to-warm-up infants are characterized by a low activity level, high initial with- drawal from the unfamiliar, slow adaptation to change, greater negativity in mood, and a moderate or low intensity of reaction.
Of the 141 children in Thomas and Chess’s study, 65 percent could be classified as belong- ing to one of these three temperament types (40 percent easy; 15 percent difficult; 10 percent slow to warm up); the remaining 35 percent displayed varying mixtures of tem- perament (Figure 7.9).
Unclassified 35%
Easy 40%
Difficult 15%
Slow to warm up 10%
Figure 7.9
Infant temperaments. Approximate percentage of children with each temperament. Based on data reported in Thomas, A., & Chess, S. (1977). Temperament and development. New York: Brunner/Mazel.
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CHAPTER 7Section 7.3 Children
Note that these temperaments don’t exhaust all possibilities. Nor do all “easy” or “difficult” chil- dren always react predictably in a given situation. Even easy infants sometimes cry and fuss; and the most difficult of little urchins might occasionally laugh and seem approachable and adaptable.
The long-term implications of infant tempera- ment are intriguing. For one thing, following a study of some 7,695 families, Jokela (2010) reports that the probability of parents having a second child is significantly affected by the temperament of the first. Parents whose first child adapts eas- ily to novelty and is alert, intelligent, and sociable are more likely to have a second child than are parents of more difficult children.
Several longitudinal studies also indicate that infants rated as difficult are at somewhat higher risk of displaying psychiatric symptoms in adoles- cence (Kapornai et al., 2007). And Kagan’s (1997) research with infants classified as highly reactive (fearful of the unfamiliar; easily distressed) or nonreactive (relaxed in the face of the unfamiliar; not easily frightened) shows that these classifica- tions might have implications for later develop- mental outcomes. In his sample, about one third of the highly reactive infants continued to be highly fearful in strange situations at the age of 14 to 21 months. In contrast, the majority of the nonreactives were calm, outgoing, and confident. And these patterns, though less clear, were still evident in some children at the age of 4 ½ years.
Note, however, that infant temperament is not always easy to classify accurately. Further- more, for many infants, temperament may be quite variable, especially during the first 2 years of life; after age 2, it appears to be far more stable.
7.3 Children
By the age of 6 or 7, the uniqueness that will mark the individual throughout life has become increasingly apparent. Four-year-old Robert sits at the Thanksgiving table as his dad explains the meaning of this day and how the pilgrims could not just run to the store to buy their food, how they made do with what they could grow. “If you were a pil- grim,” says his dad, “what would you plant?”
“Corn,” his older brother says. “And peas, and potatoes, and turnips.”
“And what would you plant, Robert?”
The majority of children are classified as “easy” or of mixed temperaments. About 10 percent are “slow to warm up.” Some take comfort behind a par- ent’s leg; others rely on the bear.
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Robert glances cleverly at his plate. “I’d plant turkeys,” he answers.
That’s the way Robert is: clever and entertaining. He has a wonderfully inventive mind, seldom limited by the rules that constrain our thoughts. His thinking is, as Pearce (1977) puts it, magical thinking; it does not always need to be checked against reality. In these early years, thinking is wishful and fantastic. It somehow assumes that reality can be changed by a thought. Thus it is that a magic spell can produce a witch or a princess, a silver thread or a pot of gold; a dream can be real, and perhaps reality too can be a dream; and a wish can make a race car of a stone, a cave of a small corner, a giant sailing ship of a discarded matchbox.
Cognitive Development in Childhood: Piaget’s Theory
But, Pearce tells us, we do not gladly accept—perhaps we don’t even understand—the magical child. Our approach to children and our scientific research ask instead: “How can the child be made to attend to reality?” or “How can we make the child abandon magical thinking?” (p. xv). The Swiss psychologist, Jean Piaget, provides some fascinating insights that have become a lasting part of the child development puzzle.
Mechanisms of Adaptation Piaget was first trained as a biologist, and he brings a biologist’s perspective to the ques- tions of development. Development, he explains, is a process of adaptation. Children are not born knowing how to cope with external reality; they’re born with a handful of reflexes that are crucial for biological survival (sucking, sneezing, and swallowing, for example). These ready-made responses allow the child to assimilate important aspects of the environment. Piaget defines assimilation as the use of previously acquired or innate activities without having to modify these activities.
But from the very beginning, the infant’s reflexes are not always suited to the demands of the environment. For example, differently placed and shaped nipples require changes in the infant’s behaviors. These changes define accommodation. Accommodation implies changes in the child’s thought and behavior in response to environmental demands.
Throughout life, assimilation and accommodation are the two ways we have of interact- ing with the environment. We make use of aspects of our environment for certain activi- ties that we already know (assimilation); and we modify our activities to be able to make use of certain aspects of the environment (accommodation).
Schemas Children are born with a limited repertoire of unlearned abilities (sucking, for example). Mental representations of these abilities are labeled schemas (also called schemata or schemes). As a result of interacting with the environment through assimilation and accom- modation, schemas (mental representations) change. In other words, mental growth takes place through assimilation and accommodation.
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CHAPTER 7Section 7.3 Children
The Stage Theory As children develop, their primitive schemas give way to more advanced representations of the world and to new ways of dealing with the world on a mental level. Piaget describes the progression of cognitive development in terms of four major stages and various sub- stages (Table 7.4).
Table 7.4 Piaget’s Stages of Cognitive Development
Stage Approximate Age Some Major Characteristics
Sensorimotor 0–2 years Motoric intelligence World of the here and now No language, no thought in early stages No notion of objective reality
Preoperational Preconceptual Intuitive
2–7 years 2–4 years 4–7 years
Egocentric thought Reason dominated by perception Intuitive rather than logical solutions Inability to conserve
Concrete Operations 7–11 or 12 years Ability to conserve Logic of classes and relations Understanding of number Thinking bound to concrete
Formal Operations 11 or 12–14 or 15 years Complete generality of thought Ability to deal with the hypothetical Development of strong idealism
Sensorimotor Thought During much of the first 2 years of life, says Piaget, infants understand the world mainly in terms of the activities they perform and the sensations that result; hence the label sensorimotor. It is a world of sensation and movement, a world that is not represented in imagination and that therefore ceases to exist when it is not being perceived. If an attractive object is shown to a very young infant and then hidden, the child will not even look for it: The object does not seem to exist when it cannot be seen or touched.
One of the important cognitive achievements of this period is the realization that objects are permanent and independent. This realization, the object concept, is possible only when the infant can symbolize—that is, can represent internally. Internal representation makes it possible for the child to imagine, to begin to think, to imitate objects and people who are not immediately present, and eventually to develop language.
Preoperational Thought Piaget labels the years from 2 to about 7 preoperational because children don’t develop the ability to deal with operations (logical thought processes) until around 7. Before then, thinking is full of contradictions and errors. As an example, Piaget describes his young son’s reaction to a snail they see while out walking one morn- ing. When they later see another snail, the boy exclaims, “Here it is again, the snail,” absolutely convinced that this is the same snail. He does not yet understand that similar objects can belong to the same class but not be identical. Billy, who sees four different
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CHAPTER 7Section 7.3 Children
Santa Clauses in four places on the same day, still knows there is only one Santa Claus. He is a pre- conceptual thinker.
Preconceptual thinkers also tend to be animistic thinkers. “Does the sun move?” Piaget (1960) asks a young child (p. 215). “Yes,” the child answers, going on to explain how the sun, like the moon, moves when he walks, stops when he stops, turns when he turns, that it must surely be alive. But even among preschoolers, animism has its limits. If the sun and the moon are alive because they move, Bullock (1985) suggests to a 4-year-old, then surely a car, which also moves, must also be alive. No, the child is not so easily fooled. How can this thing of metal and plastic and rubber pos- sibly be alive?
At around age 4, the child’s reasoning becomes somewhat more logical, although it is still heavily influenced by appearances rather than by logic. It is not so much logical as intuitive thinking.
Intuitive thought, explains Piaget, is often marked by the type of egocentrism evident in this sim- ple problem: An experimenter holds one end of a string in each hand so that a male and female doll, side by side on the string, are hidden behind
a screen. He asks the child which doll will come out first if the string is moved toward the right. Whether the child is correct or not, the boy doll is moved out and hidden again. The procedure is repeated a number of times without variation so that the boy doll always comes out first. Eventually the child will predict that the other doll will come out. Why? “Because it’s her turn. It isn’t fair.” The child interprets the problem only from a personal point of view, from an egocentric view.
Egocentricism is also evident in many preschool verbal exchanges:
Bill: I got a red one.
Sarah: My cat is sick.
Bill: Go. Go. RRRRRR.
Sarah: We don’t have a dog.
A conversation? Not really, says Piaget: More a collective monologue. A real conversation requires the nonegocentric ability to adopt another’s point of view.
This 4-year-old’s logic is intuitive, ego- centric, and perception dominated. He is easily fooled by appearances. There are still many head-scratching puzzles out there.
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CHAPTER 7Section 7.3 Children
Concrete Operations That perception tends to dominate the preoperational child’s think- ing is evident in this Piagetian demonstration: Michael, a 4-year-old, is asked to take a bead and place it in one of two containers. As he does so, a researcher places a bead in another container. They keep doing this until one of the containers is about half full. To confuse Michael, the researcher has put her beads in a shallow, flat dish whereas Michael’s container is tall and narrow. The researcher now asks, “Who has more beads? Or do we both have the same number?” “I have more,” says Michael, “because they’re higher.” Or he might just as easily have said, “You have more ’cause they’re bigger around.” In either case, his answers reflect his reliance on the appearance of the containers. This reliance on perception, even when it conflicts with logic, is one of the major differences between child and adult thought.
With the advent of concrete operations, children no longer make this mistake. They now rely on rules of logic rather than on intuition and perception. They know that quantity does not change unless something is added or taken away. In Piaget’s terms, they have achieved conservation.
There are as many types of conservation as there are quantifiable characteristics of objects: There is conservation of number, length, distance, area, volume, liquids, solids, and so on. None of these is acquired before the stage of concrete operations, and even then some (volume, for example) will not be acquired until late in that period. Experimental proce- dures and approximate ages for different conservations are shown in Figure 7.10.
Strikingly, when faced with conservation problems, preoperational children can contra- dict themselves repeatedly without ever changing their minds. After the bead demonstra- tion, for example, the experimenter can pour the beads back into their original containers and repeat the question. Michael now agrees the containers have the same number of beads; but as soon as the beads are again distributed into the tall and shallow containers, he changes his mind.
During the concrete operations period, children also develop new abilities relating to classification, seriation, and numbers. The seriation problem shown in Figure 7.11 would present insurmountable problems for a 3-year-old but would be ridiculously simple for an 8-year-old. Given the ability to classify and to seriate, understanding numbers becomes relatively simple.
By the end of the period of concrete operations, the child has acquired the ability to deal with a wide range of problems systematically and logically and is very much at home in the world of symbols. But there remain a number of limitations to thought during this period, the most obvious of which is the child’s continued inability to deal with the hypo- thetical; hence the label concrete. The logic of concrete operations is tied to real things. Children don’t yet have the freedom made possible by the more advanced logic of formal operations.
Formal Operations According to Piaget, the single most important achievement of for- mal operations is the transition to a more advanced logic that deals with hypothetical states and events. Piaget illustrates this with the following problem: Edith is fairer than Susan; Edith is darker than Lilly. Who is the darkest of the three?
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CHAPTER 7Section 7.3 Children
1. Conservation of substance (6–7 years)
The experimenter presents two identical modeling clay balls. The subject admits that they have equal amounts of clay.
2. Conservation of length (6–7 years)
3. Conservation of number (6–7 years)
4. Conservation of liquids (6–7 years)
5. Conservation of area (9–10 years)
One of the balls is deformed. The subject is asked whether they still contain equal amounts.
Two sticks are aligned in front of the subject. The subject admits their equality.
One of the sticks is moved to the right. The subject is asked whether they are still the same length.
Two rows of counters are placed in one-to-one correspondence. Subject admits their equality.
One of the rows is elongated (or contracted). Subject is asked whether each row still contains the same number.
Two beakers are filled to the same level with water. The subject sees that they are equal.
The liquid of one container is poured into a tall tube (or a flat dish). The subject is asked whether each still contains the same amount.
The subject and the experimenter each have identical sheets of cardboard. Wooden blocks are placed on these in identical positions. The subject agrees that each cardboard has the same amount of space remaining.
The experimenter scatters the blocks on one of the cardboards. The subject is asked whether each cardboard still has the same amount of space remaining.
A
B
C
D
E
A
B
C
D
E
Figure 7.10
Some tests for conservation with approximate ages of attainment.
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CHAPTER 7Section 7.3 Children
This problem of transitive inference is very difficult for the younger concrete operations child, not because it involves seriation, which has already been mastered, but because it is an abstract problem. If Edith, Susan, and Lilly were all standing in front of a 10-year-old, she could easily say, “Oh! Edith is fairer than Susan, and she is darker than Lilly—and Susan is the darkest.” But when the problem is verbal rather than concrete, it requires thinking that is more formal (abstract).
Among the cognitive tools of adolescent thinking is a powerful logic that allows the ado- lescent to deal with the hypothetical rather than only the real. One of the important con- sequences of this newfound ability is an increasing concern with the ideal. Once children are able to reason from the hypothetical to the real or from the actual to the hypothetical, they can conceive of worlds and societies that, hypothetically, have no ills.
It should be noted, however, that the ability to deal logically with the hypothetical is not a characteristic that governs all adolescent and adult thinking. Rather, it is a form of
Figure 7.11
To test children’s understanding of seriation, they are asked to order a pile of dolls by height. The top row was arranged by a 3 1/2-year-old; the bottom, by an 8-year-old.
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CHAPTER 7Section 7.3 Children
thinking that is now possible, whereas it had previously been beyond the child’s abilities. Although formal thought may be clearly evident in individual instances, it is by no means evident in all cases.
Evaluation of Piaget’s Theory Piaget’s critics typically agree on a number of standard complaints. One is that he used very few subjects in his research, which is true but not especially important unless studies with larger groups contradict his findings. In fact, as Fuson (2009) notes, of the thousands of studies that have followed Piaget’s research, the majority support his description of the general sequence of intellectual development.
However, most critics also agree that Piaget underestimated the abilities of young children. That might be because Piaget’s investigations, even with very young children, were largely verbal. When tasks are made simpler, children sometimes respond quite differently. For example, Charles and Rivera (2009) found that 5- and 6-month-old infants will often actively look for an object before they can actually reach for it. Looking for an object is a strong sign of some understanding of object permanence. Similarly, Aubrey (1993) points out that pre- schoolers have a far more advanced understanding of number than Piaget thought.
Critics also agree that whereas Piaget underestimated what younger children can do, he overestimated the capabilities of children at the stage of formal thinking. More recent studies often fail to find much evidence of formal operations thinking among adults, let alone adolescents (for example, Modgil & Modgil, 1982).
A final caution is in order: The stage aspect of theories such as Piaget’s gives the impres- sion that one day a child of a certain age is at stage X; the next day, the child wakes up at stage Y. But that, of course, is not really the case. The boundaries between stages are never entirely clear, and transitions are seldom entirely abrupt and irreversible.
Children’s Social-Emotional Development
As we saw earlier, Erik Erikson describes eight stages of psychosocial development. The theory explains how, in the very beginning, parents are all-important. Not only are they essential for the baby’s comfort and survival, but they provide for all of the newborn’s psy- chological needs. They are the infant’s source of love, and that is not a small four-letter word.
As children grow older, peers become progressively more important. But that does not mean that parents immediately become less important. Even in adolescence, peers and others outside the family don’t ordinarily completely replace parents either as a source of love or as a source of profound influence on interests, values, and decisions. Two of Erik- son’s stages span childhood (see Figure 7.13).
Initiative Versus Guilt By the age of 4 or 5, Erikson explains, children have become relatively autonomous. They have discovered that they are capable and independent. Now they will spend the
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CHAPTER 7Section 7.3 Children
rest of their childhood trying to discover exactly who they are. In early childhood, they do this by trying to be like their parents—that is, by identifying with them. At the same time, their world expands beyond the family, and as they explore this wider environ- ment, they’re called upon to exercise initiative and to overcome the sense of inferiority that threatens.
Industry Versus Inferiority From about ages 6 to 11, children interact extensively with peers. It now becomes increas- ingly important that they be accepted as worthwhile. They need to discover that they are competent, that they can do things—in short, that they are industrious. During this stage, children are anxious to learn what their culture offers them and requires of them. Failing to do so can result in a lasting sense of inferiority.
Play The socialization of the child begins in the family and continues with peers, schools, and other social institutions. Through these, children become aware of the many implicit and explicit rules that govern behavior in their culture. Much of the child’s early socialization occurs through play.
And what is play? Sadly, many of us have forgotten. We abandon ourselves reluctantly and guardedly to the joys of madness and the ecstasies of whimsy. We know too carefully what reality is, and we fear too passionately the possibility of confusing the imaginary with the real.
There is no such fear in the hearts of children. The games they play, unlike the games we play, are played solely for their enjoyment. They are designed neither to impress nor to deceive; neither to persuade nor to annoy.
Children’s games may be classified into three broad categories: sensorimotor play, imagi- native play, and social play. Many games obviously share characteristics of all three.
Sensorimotor Play Sensorimotor play is mainly physical activity such as skipping, hop- ping, jumping, running, and the countless solitary games of young children. It is the only type of play of which young infants are capable.
Imaginative Play Imaginative (or pretend) play begins very early, continues throughout life, and takes a variety of forms. Most obvious are the host of make-believe games and activities prevalent in the preschool years. Even infants as young as 1 can pretend, often by simulating common activities like pretending to eat or pretending to sleep. And by age 2, a wide range of make-believe games becomes possible as children learn to transform objects, people, and activities into whatever they wish. Many of these pretend games are suggested by the immediate environment, notes Jaffke (1996). Thus, a picture, a crooked stick, a broken teacup, a squished worm—each can inspire a new game.
Another type of imaginative play becomes increasingly common in the later preschool years and continues well into adulthood, although we spend little time talking about it.
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CHAPTER 7Section 7.3 Children
Daydreaming is a normal and healthy form of play. Evidence suggests that daydreaming may be very important in the resolution of fears, anxi- eties, and a wealth of related problems (Barber, Bagsby, & Munz, 2010). It very likely contributes significantly to creative output (Singer, 2009) and probably is also centrally involved in the develop- ment of interpersonal skills, providing as it does an opportunity for the imaginary exercising of these skills.
There is, too, the imaginary playmate with whom as many as one third of all preschool children play constantly (Singer, 2009). These imaginary friends are loved, spoken to, taken on trips, dressed, and played with. Psychology has not yet interviewed any of them in depth. Most of them go away in the earlier school years and never come back.
Social Play Social play is any type of play that involves interaction among two or more chil- dren. Thus, both practice and pretend play are social when they involve more than one child. Skipping rope alone in the darkness of one’s basement is a solitary sensorimotor activity; skipping rope out on the playground with oth- ers turning the rope and chanting “salt, mus- tard, vinegar, pepper . . .” is a cooperative or social activity. Similarly, creating daydreams in the solitude of one’s bedroom is private imagi- native play, but playing “let’s pretend—you be the veterinaman [sic] and I’ll be the dog” is social imaginative play.
Note, too, that children play solitary games before they engage in more social games, and that even
Three categories of children’s play: (a) imaginative, (b) social, and (c) sensorimotor. Note that these forms of play are not mutually exclusive. A rope-tug competition can be every bit as sensorimotor as social. And playing cowboy roles may be highly social as well as imaginative.
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CHAPTER 7Section 7.4 Adolescents
when two children are playing side by side, they are often playing independently. Piaget (1951) drew attention to this progression in children’s games, pointing out that, prior to truly social play, there is parallel play where children play together (in the sense of being in physical proximity) but neither share the activities employed in the game nor follow mutually accepted rules.
True social play requires interaction between two or more children, the use of rules, and cooperation. It is hardly surprising that it is considered one of the most important means of fostering language growth as well as cognitive, social, and emotional development in children.
Earlier research had suggested that as children begin to play more socially, they engage in less solitary play. Solitary play among older children has sometimes been seen as evi- dence of social immaturity. Xu’s (2010) research suggests that this is really not the case. She explains that cultural changes have resulted in an increasing amount of solitary play among today’s children. These changes include smaller families, frequent social isolation in larger urban centers, the mushrooming availability of games designed for solitary play on computers and hand-held devices, and the enormous amount of time children spend watching television.
7.4 Adolescents
Social play continues through the transition from childhood to adolescence and beyond.
Physical and Sexual Changes
It is not always an easy transition, complicated as it is by the gap that often exists between newly achieved biological maturity and social maturity. Although biological maturation readies the adolescent for adult roles of mating and procreation, social constraints often delay the adoption of these roles.
Biologically, adolescence is the period from the onset of puberty (sexual maturity) to adulthood. Puberty is defined as the capacity to ejaculate semen for boys and the first menstrual period (menarche) for girls. The changes that result in sexual maturity define pubescence. These changes are initiated by a dramatic increase in hormones produced by the gonads (testes in boys and ovaries in females), culminating in the ability to produce mature ova and sperm. Other signs of pubescence include the appearance of pigmented pubic hair, breast enlargement in the girl, the growth of armpit and facial hair, and a lowering of the voice. There is also a dramatic increase in height and weight just before adolescence (the growth spurt). Puberty (sexual maturity) typically immediately follows the growth spurt.
Because of wide individual variations in the ages at which these changes occur (typically much earlier for girls than for boys), the beginning and end of adolescence are not easily defined. Age 12 is often used as an approximation for the beginning of adolescence and
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CHAPTER 7Section 7.4 Adolescents
age 20 for the beginning of adulthood—although the “legal” age of adulthood varies widely in dif- ferent jurisdictions.
Early and Late Maturation In North America, sexual maturity (puberty) is reached at around age 12.8 for girls and 14 for boys. However, some girls may reach sexual maturity as young as 9; others, not until age 16; some boys, as young as 11 or 12; others, not until age 18. Evidence suggests that sexual matu- rity has been occurring earlier across the United States, especially for girls. Herman-Giddens et al. (1997) looked at the age of menarche among more than 17,000 girls in the United States. They found that average age of sexual maturation has dropped from around 17 in the middle of the 19th century to just below 13 at present.
Research indicates that early maturation is some- times an advantage for boys. Early-maturing boys are often better adjusted, more popular, more confi- dent, more assertive, and more successful in hetero- sexual relationships. They are also likely to begin dating earlier and to have first sexual intercourse earlier (Kim & Smith, 1999). However, they are also more likely to use illegal drugs and to smoke ciga- rettes (Engels, 2009; Jaszyna-Gasior et al., 2009).
Early-maturing girls, too, are more likely to engage in behaviors of which parents don’t approve, including an increased likelihood of drug use (Arim & Shapka, 2008). However, there is good evidence that most of the negative effects of early maturation disappear by young adulthood (Copeland et al., 2010).
Adolescent Egocentrism
And much of the adolescent’s egocentrism will also have disappeared by then—with exceptions.
In Piagetian theory, egocentrism is not a derogatory term; it refers less to a selfishness than to a cognitive and emotional self-centeredness. Egocentrism is apparent in children’s inabil- ity to be completely objective in their understanding of the world. For young infants, objects exist only when they are being looked at, tasted, felt, or smelled. And in the pre- school period there is evidence of egocentrism when children focus on the perceptual features of objects and respond incorrectly to conservation problems. The egocentrism of the adolescent is of a different nature.
The most important changes of adoles- cence are those that lead to sexual matu- rity. These changes occur very early for some and much later for others. Early maturation is sometimes associated with a higher likelihood of engaging in behaviors—and displaying hairstyles— of which parents don’t approve.
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CHAPTER 7Section 7.4 Adolescents
The Imaginary Audience and the Personal Fable When 15-year-old Rosa was getting ready to go to a concert, she agonized over her hair. It seemed that her mop had gone wild overnight, so now she was desperately trying to find some way of making it look decent enough that she would not be an absolute dork.
“Nobody’ll notice, you look fine,” said her mother.
“Everybody’ll see,” she retorted.
Her imaginary audience that night would consist of 30,000 people. Everybody would be watching; everybody would care. And Rosa is not excep- tionally egocentric.
The adolescent’s imaginary audience is an imag- ined collection of all who might be concerned with the adolescent’s self and behavior. It is the “they” in all those expressions “they think . . .” “they say . . .” The imaginary audience is an expression of adolescents’ belief that they are the center of attention.
In some ways, argue Bell and Bromnick (2003), the adolescent’s imaginary audience is not entirely imaginary. In fact, there are important social and personal consequences attached to what people think of the adolescent’s dress and behav- ior. And there may be negative consequences attached to ignoring the audience.
The imaginary audience, says Elkind (1967), is not a highly critical, but an admiring audi- ence. It makes sense that adolescents’ personal fables would include a supportive audi- ence. Personal fables are fantasies adolescents invent in which, not surprisingly, they are the heroes. They’re stories characterized by a feeling of being special and unique, as well as by a sense of power and invulnerability. Unfortunately, this feeling of invulnerability is often sadly inappropriate, as is evident in the fact that adolescents aged 16 to 19 are four times more likely to have vehicle accidents than older drivers (Insurance Institute for Highway Safety, 2009).
Identity Formation
A higher probability of accidents is just one of the risks of adolescence; there are others. As G. S. Hall claimed many decades ago, adolescence can be a time of storm and stress. And when there are storms in adolescence, they sometimes have to do with the problem of developing an identity, a sense of wholeness and purpose.
The adolescent’s personal fable includes feelings of being special and powerful and invulnerable and, as this lad proves, capable of awesome bicycle feats. Not surprisingly, high-risk behaviors—and accidents—are more common in this age group.
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CHAPTER 7Section 7.4 Adolescents
In Erik Erikson’s theory of psychosocial development, the conflict that labels the stage descriptive of adolescence is identity versus identity diffusion (see Figure 7.13). During this stage, the adolescent is faced with the daunting task of developing an identity. This involves decisions and choices not so much about who one is but rather about who one can be among all potential selves. The source of conflict lies in the various possibilities open to adolescents.
While in the transition between childhood and adulthood, the adolescent’s identity status typically changes as crises come and go and as the adolescent explores various options. Building on Erikson’s work, Marcia (1966, 1980) identifies four distinct types of identity status on the basis of whether the adolescent has undergone or is currently undergoing a crisis and on whether a commitment has been made to a specific identity.
Identity Diffusion Adolescents in the state of identity diffusion have made no commitment and experienced no identity crisis. These are adolescents whose political, social, and religious beliefs are ambiguous or nonexistent and who have no vocational aspirations. It is a state that’s very common in early adolescence.
Foreclosure Some adolescents, by virtue of religious, political, or vocational commitments, achieve a strong sense of identity without experiencing a crisis. This is often the case, for exam- ple, in close-knit religious communities where roles and beliefs are predetermined. It may also be the case when adolescents simply allow parents or others to make impor- tant identity-related decisions for them. The most striking characteristic of these ado- lescents, says Marcia (1980), is high adherence to authoritarian values (obedience and respect of authority).
Moratorium Erikson believed that one of the functions of adolescence was to serve as a moratorium—a period during which adolescents could experiment with various identities without hav- ing to make a commitment. Moratorium adolescents have vague, changing commitments; in this sense, they are in crisis. But it is a useful crisis because without it, there is a danger of premature commitment (as in the case of foreclosure) or of continuing lack of commit- ment (as in identity diffusion).
Identity Achieved Those who have gone through the moratorium and made a commitment are described as identity achieved. Marcia (1980) reports that identity achieved adolescents are more inde- pendent, respond better to stress, have more realistic goals, and have higher self-esteem than adolescents in any of the other three categories. However, he also emphasizes that identities are never static and absolutely permanent. Even when the adolescent appears
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CHAPTER 7Section 7.5 Adults
to have achieved an identity, further changes often occur. For example, some college students move in and out of identity crises before finally achieving a permanent commit- ment (Figure 7.12).
7.5 Adults
And even when they are adults, some never achieve any lasting commitment, never develop a strong sense of identity. They’re recognizable later in life as the full-time “fun seekers,” says Marcia (1980), or as disturbed, highly anxious individuals with low self-esteem and low confidence.
Erikson’s Stages of Adulthood
As we saw, Erikson describes human development in terms of progression through a series of adaptations that the culture requires. At every developmental stage, growth and devel- opment require new competencies. And always, there are opposing tendencies. Thus, the infant must develop trust in a world that is initially strange and sometimes terrifying. If the opposing tendency, fear and mistrust, is not overcome, it is difficult for the toddler to go out into the world, to explore and learn and develop. And the main task of adolescence is to overcome the crisis that comes with conflicting choices and the need to make a commitment.
Foreclosure commitment predetermined
by political, social, or religious affiliation
Identity achieved adultlike acceptance of
social, religious, political, or vocational alternatives
Commitment Made
Crisis No Crisis
No Commitment Identity diffusion
ambiguous belief systems; no vocational commitment
Moratorium period of exploration of
alternatives
Marcia’s four stages
of adolescent identity
development based
on crisis and
commitment
Figure 7.12
Marcia’s four states of identity development.
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CHAPTER 7Section 7.5 Adults
Adulthood brings with it a whole new set of challenges, each with powerful conflict- ing tendencies. Three of Erikson’s eight stages of the human lifespan cover adulthood (Figure 7.13).
Intimacy Versus Isolation One of the commitments that many adolescents and young adults are called upon to make requires forming intimate relationships, often, though not always, with someone of the opposite sex. But here, as in all stages of the lifespan, there is a conflict between the need to make a commitment and an unwillingness to do so. Often, says Erikson, there is a reluctance
Trust vs mistrust
0−18 months Develop enough trust in the world to explore it
Autonomy vs shame
18 months− 2 years
Develop feelings of control over behavior. Realize that intentions can be acted out
Initiative vs guilt
2 or 3−6 years Develop a sense of self by identifying with parents; develop a feeling of responsibility for own actions
Industry vs inferiority
6−11 years Develop a sense of self-worth through interaction with peers
Identity vs identity
11 through adolescence
Generativity vs self-absorption
Adulthood Assume responsible adult roles in community; contribute; be worthwhile
Integrity vs despair
Older adulthood
Face death; overcome possible despair; come to terms with the meaning of life
Intimacy vs isolation
Young adulthood
Develop close relationships with others; achieve the intimacy required for long-term commitment
Erikson’s Psychosocial Stages Principal Developmental Tasks and Important Infuences
Develop a strong sense of self (identity); select among various vocational, political, religious, or lifestyle alternatives
Figure 7.13
Erikson’s developmental tasks. Based on Erik H. Erikson (1959).
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CHAPTER 7Main Points
to give up or compromise the hard-won sense of identity that has been achieved. And, of course, in many cases, the search for identity and commitment goes on well into adulthood.
Generativity Versus Self-Absorption At every stage of the lifespan, there are different social demands placed on the individual. These can vary enormously from one person to another. What is common to most adults, says Erikson, is the expectation that they will form the sorts of caring and work relation- ships that will benefit their immediate family and friends, their community, and perhaps the world. The opposing tendency is to be self-absorbed and selfish, not willing to expend the effort required to be generative. Generativity can be evident in many areas: work, fam- ily, and wider social or political commitments.
Integrity Versus Despair The overriding psychosocial conflict in old age is one between despair at the thought that the end is at hand and the need to maintain a sense of integrity—a conviction that life has been useful and worthwhile. What the elderly need to do, says Erikson, is integrate the experiences of a lifetime, make sense of them, and achieve a feeling of acceptance and con- tentment. Failing that, the individual may be overcome with a sense of regret and despair and by the frustration that it is now too late to do anything further. We may never find those pieces of the puzzle not yet in place.
There is not always going to be a tomorrow.
Main Points 1. The Beginning: Genetics and Prenatal Development: The beginning involves
sperm and ovum forming a zygote containing 23 pairs of chromosomes, 1 pair of which determines biological sex. Chromosomes contain the tens of thousands of genes that give each of us our unique genetic code, including the occasional pos- sibility of genetically determined defects.
2. Infants: There is an enormous amount of motor and cognitive learning dur- ing the first 2 years of life, including locomotion and language. This learning is made possible by relatively well-developed perceptual systems coupled with an impressive brain. Infants vary in the amount of time they spend sleeping, cry- ing, being alert, and being active. They also vary in terms of their predominant temperaments (easy, difficult, slow to warm up).
3. Children: A sort of magical thinking characterizes childhood. But as children adapt by assimilating (using previously learned responses) and accommodat- ing (modifying responses), they become more closely attuned to reality and less given to magic. In Piaget’s description, the here-and-now world of the infant gives way to the egocentric, perception-dominated, intuitive world of the preschooler, then to the reality-based, concrete-operations world of the young child, and finally to the more logical and idealistic world of the adolescent. Play has a fun- damental role in the socialization of the child.
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CHAPTER 7Main Points
4. Adolescents: The transition from childhood to adulthood is defined by sex- related changes (pubescence) leading to sexual maturity (puberty). The adoles- cent’s egocentrism is evident in the imaginary audience and the personal fable (which brings with it a sometimes dangerous sense of invulnerability). The prin- cipal task of adolescence is to arrive at a commitment (a decision regarding who one can and should be) and to overcome related crises.
5. Adults: Adulthood brings new challenges having to do with establishing inti- mate relationships, making worthwhile contributions (being generative in vari- ous spheres), and, in the end, reconciling one’s life and developing a notion that it has been worthwhile.
Study Terms
accommodation
active vocabulary
alleles
animistic thinkers
artificial insemination
assimilation
chromosomes
conception
conservation
daydreaming
deoxyribonucleic acid (DNA)
difficult infants
dizygotic
dominant gene
dyadic interactions
easy infants
egocentrism
embryo
fallopian tube
fast mapping
genes
genotype
gonads
holophrases
identity
imaginary audience
imaginary playmate
in vitro fertilization
infancy
intuitive thinking
magical thinking
menarche
monozygotic
nature-nurture controversy
object concept
operations
ovum
passive vocabulary
personal fables
phenotype
placenta
play
protowords
psychosocial development
puberty
pubescence
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CHAPTER 7Main Points
recessive gene
schemas
sensorimotor
sex chromosome
sex-linked defects
slow-to-warm-up infants
socialization
sperm cells
temperament
transitive inference
umbilical cord
uterus
zygote
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8
Personality
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • How is personality defined? • What are trait-type approaches to personality? • What are the Big Five? • What are the main beliefs of biological approaches to personality like Sheldon’s
and Eysenck’s? • How does Freud describe normal and abnormal personality development? • What is self-actualization? • What are some common examples of projective personality measures? • What are the uses of some common nonprojective personality tests?
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CHAPTER 8Personality
Part of me suspects that I’m a loser,
and the other part of me thinks I’m God Almighty.
—John Lennon, The Beatles Anthology
Chapter Outline
8.1 Personality Personality and Self
8.2 The Common-Sense Approach
8.3 The Trait-Type Approach Early Trait-Type Approaches The Big Five Stability of Personality
8.4 Biological Approaches Sheldon’s Body Types Eysenck’s Biological Theory
8.5 A Psychodynamic Approach: Freud Freud’s Basic Ideas Psychosexual Stages Normal and Abnormal Personality Defense Mechanisms Review of Freudian Theory
8.6 Learning-Based Approaches Behaviorism Bandura’s Social Cognitive Theory Rotter’s Cognitive Approach
8.7 Humanistic Approaches Abraham Maslow’s Self-Actualized Person Rogers’s Phenomenology
8.8 Measuring Personality Variables Projective Measures Nonprojective Measures Some Cautions
John Lennon was, in many ways, an extraordinary individual. Even at a very young age, he thought himself not only different, but gifted. “I was different, I was always different. Why didn’t anybody notice me?” he asks.
Later on, people certainly did notice him. But his early childhood was somewhat turbulent. His father was largely absent through his early years, leaving John to be raised by an aunt. And she, according to John, had little appreciation for his talents. “I used to say to me auntie” (Mimi Smith), he is quoted as saying, “You throw my f*ckin’ poetry out, and you’ll regret it when I’m famous, and she threw the bastard stuff out. I never forgave her for not treating me like a f*ckin’ genius or whatever I was, when I was a child. It was obvious to me” (The Rolling Stone Interview, 1971).
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CHAPTER 8Section 8.1 Personality
8.1 Personality
The fact is, we are all different (although we are not all geniuses): We all have a per-sonality—a collection of characteristics that defines our person. In a general sense, personality can be defined as stable characteristics, including abilities, talents, habits, preferences, weaknesses, moral attributes, and predominant moods, that vary from one person to another.
The word personality comes from the Latin word persona, which referred to the masks worn by Roman actors. Using these masks, an actor could play many different roles in a single play. A persona was, in a very literal sense, a way of changing one’s personality, a way of becoming somebody else.
In one sense we all make use of personae (masks or roles): We appear to be different people in different situations. The type of behavior expected of us in formal situations is often quite different from that which we display in less formal circumstances. There is a type of self-revelation made possible in intimate circumstances that is impossible for most people when interacting with strangers. In public, our masks are more impenetrable.
But we do not have an unlimited choice of masks. Our roles are limited by our abili- ties, our inclinations, and our talents. We cannot just decide that we will be unselfish and all wear unselfish personae. For some, tendencies toward jealousy and greed make it impossible to be unselfish at all times. Their prevailing personality is simply incompatible with that persona. So too with each of us: There are some “selves” that you and I will never be, much as we might like. And there are many selves we sometimes see in others that we would never select for ourselves.
Personality and Self
Note that the terms self and personality are very closely related. The self is essentially the person viewed from inside. My self is me as I see myself. Personality is the self, too, but from a different view; it is the self as viewed from the outside. In other words, it includes those aspects of my self that I present to the world. The correspondence between the two may be very high (as in an “open” person) or quite low. Presumably, the more closely our personae resemble our true selves, the more similar will be our selves and our personalities.
We all make use of masks, personality theorists tell us: We’re different in dif- ferent situations. And though our masks might not be as obvious as this guy’s, they are often no easier to see behind.
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CHAPTER 8Section 8.2 The Common-Sense Approach
The Real Person When someone does some horrendous thing to a cat or a car, neighbors are often shocked: “I would never have guessed in a million years. I can’t believe that’s the real him.” But, at least in one sense, it is the real him, because we cannot easily separate people from their actions.
Striking as one person’s violation of his neigh- bors’ expectations might be, we should not over- look the other 40 people on his block whose behavior surprises no one. The woman who is known to be friendly and outgoing can always be counted on to organize block parties; the man who is conscientious continues to be thoughtful and well organized; and it is expected that the person who is somewhat neurotic will some- times be moody and anxious. All these people exhibit behaviors consistent with what psychol- ogists would identify as their dominant person- ality characteristics.
Understanding how to identify and measure the factors that determine consistency in behavior is the piece that personality theorists have struggled to contribute to the human puzzle.
8.2 The Common-Sense Approach
Being effective in a social environment requires a basic understanding of others—of their likely and unlikely behaviors, their probable actions and reactions. Those unlucky individuals who are less skilled at understanding others often seem inept and tactless and maybe a little socially unintelligent.
But even those who pride themselves on their “social intelligence” tend to operate with highly global notions of what other people are like and of what they are like themselves. Stagner (1958) provides a striking demonstration of this fact. An unethi- cal salesman (experimenter) approaches a number of personnel managers with a new personality test. The test is absolutely worthless, but managers are told that it is an excellent personality test. They are invited to take it themselves and to buy it only if they are impressed with reports of their own personalities. After taking the test, each of 68 personnel managers is presented with statements such as these:
You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations.
Although the behavior of those we know well is sometimes unexpected, it doesn’t often violate our expectations. Generally, those who are friendly and outgoing, as is this woman, greet us warmly. Unless we’ve done them wrong.
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CHAPTER 8Section 8.2 The Common-Sense Approach
While you have some personality weaknesses, you are generally able to compensate for them.
You have a tendency to be critical of yourself. (Stagner, 1958, p. 348)
In this study, 91 percent of the managers thought the first statement was “rather good” or “amaz- ingly accurate”; 89 and 92 percent thought the same thing of the second and third statements, respectively. This phenomenon is labeled the Bar- num effect (after the founder of the famous circus, who claimed he had something for everyone). A large number of studies have since reported cor- roborating findings (for example, Claridge, Clark, Powney, & Hassan, 2008; Wyman & Vyse, 2008). Rogers and Soule (2009) also found the Barnum effect among both Western and Chinese par- ticipants who were asked to rate the accuracy of astrological predictions. But they also found that those who were better educated or who had some background in psychology were less likely to fall victims to the Barnum effect.
It is little wonder that graphologists (handwriting analysts), phrenologists (those who interpret per- sonality on the basis of head contours), astrologers (those who look to the alignment of stars, planets, and moons), and palmists (palm read- ers) have sometimes not required a great deal of training in their respective endeavors.
The point of the Barnum effect research is that there are certain things that most people believe about themselves. A common-sense approach to personality might accept these beliefs as descriptive of all people. In fact, however, the vague and general statements typically used in this research are not very revealing at all. They say nothing about what makes people different from one another, or even very much about how people might be alike.
Psychology, for its part, offers a variety of approaches and theories, none of which is exclusively correct or categorically wrong. They simply represent different orientations and different emphases.
Since personality is a function of many different forces, it is not surprising that different theories often concentrate on different things. Much of what you are is a function of your genetic composition; biological factors are therefore important in determining manifested personality. Similarly, private experience, social situations, cognitive factors, and psycho- dynamic forces may all be involved in personality. This suggests at least six approaches to personality theory: common-sense, trait-type, biological, psychodynamic, learning-based, and humanistic (Table 8.1).
The Barnum effect describes our ten- dency to believe vague but plausible generalities such as might be offered by a fortune-teller or a palm reader. “We’ve got something for everybody; come into the big tent!!”
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CHAPTER 8Section 8.3 The Trait-Type Approach
Table 8.1 Approaches to Understanding Personality
Approach Major Concerns Representative Theorists
Common-Sense Why did she do that? Does he like me? What is she really like?
You
Trait-Type Discovering and verifying the existence of related clus- ters of traits that compose personality types
The Greeks Jung Costa and McCrae
Biological Looking at genes (genomics) and at brain structures and functions (neuropsychology) to identify processes and structures underlying personality
Eysenck Sheldon Researchers in genomics and neuropsychology
Psychodynamic Clarifying the interplay of unconscious forces; under- standing the conflict between basic inclinations and social/environmental constraints
Freud Jung
Learning-Based Personality as learned habits, predispositions, atti- tudes; also look at rational contributions to behavior and emotions, decision making, attributions
Watson Skinner Bandura Rotter
Humanistic The self; worth, dignity, individuality Maslow Rogers
Note that some of the theories and principles discussed in relation to each of these approaches include aspects of other approaches. The decision that one position is a trait- type approach rather than social, or biological rather than psychodynamic, is based on the main characteristics of the position, but not on all its characteristics; some approaches represent more than one orientation.
8.3 The Trait-Type Approach
The thousands of adjectives, nouns, and phrases that can be used to describe people are all examples of trait names. A trait is any distinct, consistent quality in which one person can be different from another. There are physical traits (blond, big, buxom), behav- ioral traits (quick, quiet, quarrelsome), moral traits (bad, base, benign)—more than 17,000 possible traits (Allport & Odbert, 1936).
One approach to personality has been to attempt to reduce the total number of possible traits to a few highly representative adjectives. The most useful would be those most often displayed in human behavior, most variable from one person to another, and most dis- tinct. Typically, all synonyms or near-synonyms are excluded from such lists, and an effort is made to pair the words as opposites. Thus, a person can be emotional or stable, humble or assertive, outgoing or withdrawn.
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CHAPTER 8Section 8.3 The Trait-Type Approach
Another way of looking at a trait is to say that it implies a prediction about behavior. To say that an individual is bold is to predict that that person is more likely to act boldly than are other people in similar circumstances. That, however, is some distance from saying that a bold individual will always act boldly. Knowledge of predominant personality traits sim- ply allows predictions that are more probable than those based solely on intuition.
Among the best known of the trait approaches is that proposed by Cattell (1946), who reduced Allport and Odbert’s list of more than 17,000 adjectives by eliminating all syn- onyms, obscure and infrequent words, and apparently irrelevant terms. After extensive analysis of individuals who had been rated by close friends using Cattell’s adjectives, he further reduced the list to 16 traits by combining separate but closely related traits using a process called factor analysis. This is a statistical procedure that analyzes correla- tions among variables and combines those that are closely related. It is commonly used to reduce large numbers of related variables—such as traits—to a smaller number of mean- ingful categories. Some of the 16 personality traits that resulted from Cattell’s work are shown in Figure 8.1.
Cattell is now widely recognized as the founder of current personality and trait measure- ment (Denis, 2009). His approach to identifying and measuring personality traits contin- ues to be widely used.
Type is a more inclusive term than trait. Whereas a trait is inferred from a tendency to behave in a given way in certain situations, a type is a grouping of related traits. For example, Type A personality is defined as individuals who are characterized by traits such
Conservative Experimenting
Emotional Stable
Forthright Shrewd
Expedient Conscientious
Humble Assertive
Placid Apprehensive
Practical Imaginative
Relaxed Tense
Shy Venturesome
Sober Happy-go-lucky
Trusting Suspicious
Figure 8.1
Some of Cattell’s 16 personality traits, based on popular adjectives that can be used to describe people in meaningful ways. The traits are arranged in pairs of opposites.
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CHAPTER 8Section 8.3 The Trait-Type Approach
as aggressiveness, competitiveness, high need for achievement, and perhaps other traits such as low frustration tolerance, impatience, and rudeness.
It is important to note that traits and types are not the causes of behavior, but indicate, instead, certain identifiable consistencies in behavior. Thus, people do not fight because they are hostile; but because they fight, we describe them as hostile. If causes can be iden- tified, they may be as much in the situation as in the person.
Early Trait-Type Approaches
An ancient approach to personality types was suggested by Greek philosophers, who described four distinct types of individuals: the sanguine (optimistic and happy); the melan- cholic (unhappy, depressed); the choleric (of violent temper); and the phlegmatic (apathetic, not easily moved to excesses of emotion). They thought that each of these personality types depended on fluids in the body—then called “humors.” The sanguine individual had a preponderance of blood; the melancholic, of black bile; the choleric, of ordinary bile; and the phlegmatic, of phlegm. Unfortunately, science has revealed us not to be so simple; that piece of the puzzle is now only of historical interest (Figure 8.2).
A widely accepted typology was originated by Carl Jung (1923), whose theory, like that of Sigmund Freud, was a psychodynamic theory. Psychodynamic theories are based on the belief that behavior is motivated by unconscious forces. These theories emphasize the inter- play between unconscious and conscious motives. Freud, as we see shortly, believed that
• melancholic • (unhappy; depressed)
• choleric • (of violent temper)
• sanguine • (optimistic; happy)
• phlegmatic • (apathetic)
ric olent er)
• mela • (unha d epre
• sang • (optim
happ
matic hetic)
ordinary bile
black bile
phlegm blood
Figure 8.2
The ancient Greek classification of personality types and their biological bases. Unfortunately, we are not quite so simple.
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CHAPTER 8Section 8.3 The Trait-Type Approach
the most important of these unconscious motives were sexual; Jung didn’t agree. He, unlike Freud, believed that many of our unconscious motives stem from archetypes. Archetypes are a sort of unconscious shared historical memory—part of what he labeled the collective unconscious.
Among the most common archetypes, explains Jung, are the man/woman dichotomy (his labels are anima/animus). In a sense, these archetypes serve as motives that impel us to accept mascu- line and feminine characteristics. Similarly, there is an archetype relating to God, and this, he sug- gests, accounts for the existence of religions.
In his personality theory, Jung proposed two main types that include great clusters of traits: extraver- sion (also spelled extroversion) and introversion. These represent the two possible attitudes with which all people approach life, Jung explained. On the one hand, there are extroverts—those who run toward life, adventurous, bold, eager to live and to experience, concerned with others, with sports, with all the external world. Extro- verts are fun-loving, outgoing, friendly, and active.
Introverts, on the other hand, are those who turn inward and away from the world (intro meaning inward). They are concerned more with subjective than objective reality. Intro- verts are described as timid and quiet. They avoid social interaction and dislike adventure and physical risk.
The Big Five
Jung’s ancient typology is a puzzle piece that has withstood the test of time: Today’s per- sonality theorists agree overwhelmingly that extraversion and introversion represent a consistent and important dimension of human personality. But they also agree that these two labels represent only one of five personality types—commonly labeled the Big Five factors (or the Five Factor Model).
The five factors were discovered independently by different researchers and have been extensively investigated over the years (Digman, 1990). Much of this research uses factor analysis to look at how different traits tend to co-occur. This has allowed personality theo- rists to reduce a very large number of traits to five big factors, each of which is one extreme of a pair of opposite types. Thus, extraversion is one of the five factors, but introversion is not: It is simply the opposite of extraversion.
The Big Five factors, which are thought to include most of the traits that describe person- ality, are conscientiousness, agreeableness, neuroticism, openness, and extraversion. As a memory aid, note that the first five letters spell the acronyms CANOE or OCEAN.
Jung’s typology describes introverts, who are more timid and quieter, and extroverts, who, like this young girl, are bold, adventurous, outgoing, and not averse to being the center of attention.
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CHAPTER 8Section 8.3 The Trait-Type Approach
Extraversion Those who are extraverted tend to be outgoing, to seek stimulation, to want to be in the company of others. They are engaged in the world, highly sociable and lively. At the other extreme are the introverts—those who shy away from social interaction. Whereas extraverts tend to be gregarious, assertive, and bold, introverts tend to be solitary, with- drawn, and more timid. This does not mean that introverts are necessarily shy and have no friends. But research indicates they are likely to have fewer friends, that they are more socially reserved (Selfhout et al., 2010).
Openness Openness is characterized by a high degree of inventiveness, adventurousness, and curi- osity. Those who are highly open seek out new experiences; they want to know, to dis- cover, to find out things. Openness implies an appreciation for things that are different and unusual, for art and imagination. The opposite dimension is characterized by a more rigid, conventional, traditional approach to life. Those who are closed rather than open prefer that things be straightforward and obvious rather than complex and ambiguous. Highly creative individuals tend to score high on the openness factor (Sung & Choi, 2009).
Neuroticism Neuroticism is marked by fluctuating emotions, high anxiety, and a tendency toward negative moods such as anger and depression. Those who score high on this factor are sometimes described as emotionally unstable. They tend to be more vulnerable to the effects of stress and are more often in a bad mood. In contrast, those who score low on the neu- roticism scale tend to be emotionally stable and calm when faced with stressful events. They are generally characterized by positive rather than negative moods.
Conscientiousness Those who are careful and highly responsible score high on the conscientiousness scale. They are marked by a high degree of organization, self-discipline, thoroughness, and a need to achieve. Such individuals are often described as perfectionists or workaholics. They tend to be highly diligent, well-prepared workers (Woodman, Zourbanos, Hardy, Beattie, & McQuillan, 2010). In contrast, those who score low on conscientiousness display a lower need for achievement. They are more laid back, less disciplined, less compulsive.
Agreeableness Agreeable people are those who are friendly and easygoing. They strive to be pleasant and cooperative. They are polite and compassionate, they value friendships, and they tend to have an optimistic view of people. In contrast, those low on the agreeableness factor are more suspicious of people, have a lower opinion of human nature, and are less likely to try to be accommodating and friendly. Research suggests that anger and hostility may be associated with low agreeableness scores (Sanz, Garcia-Vera, & Magan, 2010). (See Figure 8.3 for a summary of the Big Five approach to personality types.)
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CHAPTER 8Section 8.3 The Trait-Type Approach
Stability of Personality
Some theorists believe that personality changes dramatically depending on the situation. For example, Mischel (2004) showed that scores on personality tests are not very useful in predicting a given individual’s behavior in any specific situation. Behavior often seems to depend on the specific situation, taking into account the person’s immediate emotions and goals.
On the other hand, there is strong evidence that personality traits are relatively stable over much of the lifespan (Bolkan, Meierdiercks, & Hooker, 2009). And there is considerable evidence that measures of the Big Five factors are highly useful in predicting typical pat- terns of behavior (McCrae & Costa, 1997). Although such measures do not lead to highly reliable predictions of what Sam will do tonight, they allow us to make very useful general predictions about how Sam is likely to behave in a wide variety of situations over a long period of time.
Although the Big Five factors are widely researched and widely accepted in personality theory, the approach has its critics. Some suggest that there are other important factors not included in the model—factors such as honesty, sense of humor, masculinity-femininity, and conservativeness (Block, 1995). Others, such as Mischel (2004), argue that the factors
Neuroticism vs stability
(emotional, anxious, prone to negative moods)
Openness vs closedness
(adventurous, curious, imaginative)
Conscientiousness vs carelessness
(organized, disciplined, achievement-oriented)
Agreeableness vs unfriendliness
(pleasant, cooperative, friendly)
Extraversion vs introversion
(outgoing, sociable, lively, assertive)
The Big Five
Figure 8.3
The Big Five factor model. A typology of human personality.
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CHAPTER 8Section 8.4 Biological Approaches
do not predict individual behaviors well. Still others point out that the five factors are based on statistical analyses of personality tests but lack a theoretical basis.
Note that trait-type approaches to personality are primarily descriptive: Their main con- cern is to describe and label the dimensions of personality rather than to explain how personality develops. In contrast, learning-based and biological approaches are more con- cerned with the causes of personality.
8.4 Biological Approaches
Biologically oriented theories, for example, look at genetics as an important cause of human personality characteristics. Genomics is the discipline in genetics that tries to map the human genome and establish its relationship to human characteristics.
Whether genomics will find a demonstrable link between genes and personality has been a hotly debated question. But research with identical and fraternal twins strongly suggests that genetics does play a role. For example, in their study of 250 pairs of twins, Jang and Livesley (2006) found very high correlations for identical twins on each of the Big Five personality factors (Figure 8.4). And this finding has been found to hold in different cul- tures (Yamagata et al., 2006).
Dizygotic
Monozygotic
C o
rr el
at io
n s
b et
w ee
n m
em b
er s
o f
tw in
p ai
rs
Ne ur
ot ici
sm
Ex tra
ve rsi
on
Op en
ne ss
Ag re
ea ble
ne ss
Co ns
cie nt
iou sn
es s
0
0.1
0.2
0.3
0.4
0.5
0.6
Figure 8.4
Correlations between 123 identical and 127 fraternal twin pairs for the Big Five personality fac- tors—strong evidence of a genetic contribution to personality. (Based on Jang and Livesley, 2006.)
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CHAPTER 8Section 8.4 Biological Approaches
Research in neuropsychology also looks for the biological bases of personality character- istics and disorders. For example, some research indicates that high impulsivity may be linked with deficits in frontal and temporal lobe functioning—deficits that might be due to injury, disease, or genetics (Seres, Unoka, Bodi, Aspan, & Keri, 2009). In its extreme forms, impulsivity is a trait that may be characteristic of borderline personality disorder (dis- cussed in Chapter 9).
Although the links between genes, neurological functioning, and personality are still not very clear, the area is an exciting and promising field of current research. There, neuro- psychology and genomics may well uncover some key corner pieces of the human puzzle.
Sheldon’s Body Types
Among the first well-known systematic investigations of the relationship between bio- logically determined characteristics and personality traits was Sheldon’s (1954) monu- mental study of body type. He began by looking at some of the common stereotypes people have about physical appearance and personality. Is the fat person really happy and outgoing? Is the well-built person athletic and adventurous? Is the frail person intel- lectual and artistic?
Sheldon approached this problem by sorting 2,000 photographs of people into three cat- egories based on general body types: endomorph, mesomorph, and ectomorph. Endomorphs are the larger individuals. Mesomorphs are muscular and strong and of medium weight. Ectomorphs are frail and slender.
After classifying body types into categories, Sheldon and his coworkers interviewed large groups of individuals to determine the relationship between body type and personality. They report an extremely high correspondence between the two, with the principal char- acteristics of each being as shown in Figure 8.5. Thus, Sheldon apparently confirmed that endomorphs are complacent, tolerant, concerned with eating, and highly sociable; that ecto- morphs are withdrawn, secretive, and concerned with intellectual matters; and that meso- morphs are adventurous, bold, and loud.
Sheldon cautioned, however, that very few individuals fall solely into one category. Although many people tend to be more one type than another, most are actually a com- bination of all three body types. Thus, it is possible to identify the predominant tempera- ment of an individual by analyzing body type, but personality characteristics pertaining to other body types may also be present.
Research on Somatotypes Many investigations of the relationship between body type and personality have found very low relationships between the two (for example, Hood, 1963). Still, there are a hand- ful of studies that report findings very similar to some of Sheldon’s.
Why should body build be related to personality characteristics? Sheldon’s argument was that temperament is constitutional (hereditary) in the same way as is body build, and
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CHAPTER 8Section 8.4 Biological Approaches
that environmental influences are of minimal importance. It may be, as some genomics research with animals suggests, that personality characteristics are, at least to some extent, determined by genetics (for example, van Oers & Mueller, 2010).
Other explanations suggest that it is the types of activities and interactions facilitated by body build that may be most responsible for any relationship that might be found between personality and physical characteristics. The mesomorph, whose body is better suited to robust physical activity, is more likely to be athletic. Not surprisingly, research provides corroboration: Athletes in many sports are more likely to be mesomorphs (Galaviz & de Leon Fierro, 2007). Similarly, a mesomorphic build may lead more easily to violence and aggression—as Sheldon had predicted. A study by Maddan, Walker, and Miller (2008) provided some evidence for this prediction by comparing body type to the kinds of crimes a sample of prisoners had committed. And that mesomorphic builds are more attractive to the opposite sex than either ectomorphic or endomorphic builds has been confirmed in various studies (for example, Dixson, Dixson, Bishop, & Parish, 2010). This, too, may explain some of the mesomorph’s personality traits.
The frail ectomorph, by contrast, may experience more difficulty with physical activity. One of the consequences of this trait may be subsequent difficulty with social interac- tion, since much of the early learning that is important for effective socialization occurs in the physical activities of childhood. Consequently, the ectomorph turns inward, becomes withdrawn, and is more likely to develop solitary interests such as those exemplified by
Endomorph • Relaxed • Love of comfort and food • Sociable • Tolerant and complacent
Mesomorph • Love of adventure • Need for exercise • Physical courage • Assertive and bold
Ectomorph • Restrained in movement • Love of privacy • Socially inhibited • Hypersensitive to pain
Figure 8.5
Sheldon’s classification of body types and corresponding personality traits; an interesting but controversial approach to personality that has received both support and criticism.
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CHAPTER 8Section 8.4 Biological Approaches
the arts. And the endomorph may be seen as compensating for a tendency toward obe- sity by becoming gregarious and outgoing, by adopting a loving, good-willed, hedonistic approach to life.
There is another possible explanation based on the effects of social expectations. This argument maintains that the frail person is expected to be interested in intellectual mat- ters; the person who looks like an athlete is expected to be aggressive and active; and the larger person is expected to be friendly and relaxed. According to this explanation, the pressures of social expectations influence personality development.
Eysenck’s Biological Theory
But social expectations, explains Hans Eysenck (1947, 1967), are not as important as biol- ogy. One of Eysenck’s basic premises is that we are born with tendencies to behave in cer- tain ways. He initially thought that only two dimensions (types) were needed to describe human personality: extraversion and neuroticism (as opposed to introversion and emo- tional stability). Later, in collaboration with his wife, he added a third dimension: psy- choticism (as opposed to self-control) (Eysenck & Eysenck, 1976).
Eysenck uses the terms extraversion and introversion in much the same way as they are used in the Five Factor model. Neuroticism refers to a personality dimension ranging from emotional instability to stability. And psychoticism denotes high aggression, antisocial ten- dencies, and high egocentrism—contrasted with high self-control and respect for author- ity, rules, and laws.
Analysis of numerous personality tests led Eysenck to the conclusion that these dimen- sions of personality are essentially independent. An individual can be high on one with- out being high on the other, or can be high or low on all three. And although the tendency to be neurotic or extroverted (or their opposites) is largely genetically based, Eysenck does not rule out the influence of the environment. What he says, essentially, is that individu- als who score high on the neurotic factor have less stable (more labile) types of nervous systems and are more likely to acquire conditioned anxieties. This is principally because they react too strongly to situations that would evoke less intense emotional responses from individuals lower on a neuroticism scale (Figure 8.6).
Research Evidence Much of Eysenck’s experimental work has been directed toward establishing the validity of these personality dimensions and their biological bases. A basic assumption underly- ing the theory is that the nervous systems of extroverts and introverts differ, as do those of neurotics or psychotics and normal people. Accordingly, he predicted that extroverts should have lower levels of cortical excitation (low arousal levels) than introverts. Pavlov had already demonstrated that conditioning is closely related to level of cortical activity, with animals whose brains were most active conditioning more rapidly than others whose brains were typically at lower levels of arousal. If extroverts have more inhibited cortexes (lower arousal levels at resting states), they should condition more slowly than introverts. This prediction is supported by research (Eysenck, 1967).
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CHAPTER 8Section 8.4 Biological Approaches
Other indirect tests of Eysenck’s theorizing come from studies of personality disorders and in countless practical applications of the personality test he developed (Revised Eysenck Personality Questionnaire). Using this test, researchers have found strong relationships between high introversion and suicide attempts (Li & Lei, 2010). Others have reported a relationship between happiness and low neuroticism (Robbins, Francis, & Edwards, 2010). The test has been found to be generally useful for identifying individuals at risk of mental disorders in a wide variety of different settings and cultures (Kokkinos, Pan- ayiotou, Charalambous, Antoniadou, & Davazoglou, 2010).
Eysenck’s Organization of Personality Eysenck’s view of the structure of personality may be summarized as follows: Our ner- vous systems differ in important ways from those of people who have fundamentally dif- ferent personality characteristics. Basically, we inherit greater or lesser tendencies toward introversion-extroversion, neuroticism-stability, or psychoticism-self-control. These ten- dencies are evident in the functioning of our nervous systems. In turn, the tendencies give rise to behavioral predispositions, labeled traits. The traits themselves are translated into patterns of responding that we label habits. Specific habits manifest themselves in our actual responses. Thus, personality is hierarchically structured.
As an example of the hierarchical nature of personality, consider Ebenezer Goring, who finds himself telling jokes to a group of strangers on a commuter train out of New York. There is a high probability that he would score near the top on an extroversion scale; hence his type is high extrovert-low introvert; the trait he is manifesting might be labeled sociability; the relevant habit is entertaining strangers; and the specific behavior is telling this story at this time, in this situation.
neurotic
stable
controlled extraverted
introverted psychotic
Figure 8.6
Eysenck’s three dimensions of personality. Each dimension is independent of the others, so that one individual might be high on two different factors and low on the third; another might be high on one and low on the other two.
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CHAPTER 8Section 8.5 A Psychodynamic Approach: Freud
Had we known beforehand the extent of Ebenezer’s extroversion, we might have pre- dicted a behavior not unlike that observed. Theorists who have been more concerned with the identification and measurement of specific traits, however, would point out that, had we been aware of the extent of his trait of sociability, the same prediction could have been made. And if we had known of his habit of telling jokes to strangers, our prediction would have been even more accurate. Consider, however, how much simpler and more economical it is to be able to classify traits or types than to classify habits. In addition, habits change; traits and types are more enduring.
8.5 A Psychodynamic Approach: Freud
And even more enduring than traits and types, claimed Freud, are deep-seated psycho-logical forces, sometimes instinctive, often unconscious, that interact with the envi- ronment to produce personality and guide behavior. Like Jung’s, his is a psychodynamic approach to personality—so called because it emphasizes the interaction of unconscious emotional and mental processes and their influence on personality and behavior.
Freud’s Basic Ideas
Among the most basic of Freudian notions is the belief that powerful instinctual ten- dencies account for human behavior and development (Freud, 2003; Lear, 2005; Roazen, 1975). Most important among these are the urge to survive and to procreate (labeled eros after the Greek word for love). Because survival is not ordinarily threatened by reality, it is of secondary importance. Far more important in Freud’s theory is the urge to procre- ate, which meets with considerable social resistance. Sexual urges are so important in this theory that they warrant a separate label: libido.
A second important instinctual urge in Freud’s system is the death wish (labeled thana- tos after the Greek word for death). Freud thought that this instinct is sometimes mani- fested in high-risk behaviors (such as car-racing, skydiving, and related sports) and, more importantly, in aggressive behaviors. As a result, he gives sexuality and aggression a cen- tral position in his theory. These two forces are the main motivators of our behaviors, Freud explained, but their influence is largely unconscious: We are not ordinarily aware that many of our behaviors have sexual or aggressive significance.
Three Components of Personality There are three broad, sequential stages of personality development, says Freud. These are manifested in the development of id, ego, and superego.
Id The Freudian infant is all primitive instincts, a bundle of unbridled psychic energy seeking almost desperately to satisfy urges that are based on the drive to survive and to procreate. These urges, labeled id, are a lifetime source of energy; they are the basic, underlying motive for all we do.
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CHAPTER 8Section 8.5 A Psychodynamic Approach: Freud
Unlike older children and adults, the infant has no idea of what is possible or impossible, no sense of reality, no sense of right and wrong, no inter- nal moral rules that govern conduct. As a result, says Freud, the infant is driven by an almost over- whelming urge to obtain immediate satisfaction of impulses. An infant who is hungry does not wait; right now is the time for the nipple and the sucking!
Ego But life is harsh, and almost from birth, there is an abrupt clash between these powerful libidinal urges and reality. Even hunger, the most powerful of the survival-linked drives, cannot always be sat- isfied immediately. The reality is that the infant’s satisfaction has to be delayed or denied. Even def- ecation cannot always occur at will; mother says “no!” This constant conflict between id impulses and reality results in the development of the sec- ond aspect of personality, the ego.
This rational component of human personality grows out of a realization of what is possible and what is not. It develops as a result of a child’s experiences that lead to the realization that delay- ing gratification is often a desirable thing, that long-term goals sometimes require the denial of short-term goals. Although the id wants immedi-
ate gratification, the ego channels these desires in the most profitable direction.
Superego The id and the ego work together. Both have the same goals: satisfying the needs and urges of the individual. But the third component of personality—the super- ego—has a different agenda.
The superego (or conscience) begins to develop in early childhood, says Freud, and results mainly from the child’s identifying with parents. Identification involves attempting to become like others—adopting their values and beliefs as well as their behaviors. By iden- tifying with their parents, children learn the religious and cultural rules that govern their parents’ behaviors; these rules become part of the superego. Because many religious, social, and cultural rules oppose the urges of the id, the superego and the id are often in conflict. Freud believed that this conflict underlies many mental disorders and accounts for much deviant behavior (Figure 8.7).
Psychosexual Stages
Parallel to the development of the three aspects of personality is the child’s progression through what Freud labels the psychosexual stages. A psychosexual stage is a developmental
The Freudian infant is all id, says Freud—desperate to satisfying imme- diate urges, with no notion of what is possible or realistic. Feed me now!! Or, of course, I’ll cry.
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CHAPTER 8Section 8.5 A Psychodynamic Approach: Freud
stage characterized by identifiable sources of sexual gratification and by behaviors related to these sources of gratification. Through the course of development, these sources of gratification change; with each major change, a new developmental phase appears.
To make matters simple, the stages are labeled according to the area or activity that pro- vides the greatest source of sexual gratification. In chronological order, they are oral, anal, phallic, latency, and genital. The ages corresponding to each of these stages and their major characteristics are summarized in Table 8.2.
Figure 8.7
Freud’s three components of personality. The part of which we are conscious is like the tip of an iceberg; most is unconscious. Instinctive urges (the id) are present from the beginning. The ego develops as the individual becomes aware of what is possible and what is not. The super- ego builds as a result of contact with social reality, and it is typically in conflict with the id.
Conscience
Id
Conscious portion
Conflict area
Mediator/Buffer
Unconscious portion
Dark, basic urges
EgoSuperego
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CHAPTER 8Section 8.5 A Psychodynamic Approach: Freud
Table 8.2 Freud’s Stages of Psychosexual Development
Stage Approximate Age Characteristics
Oral 0–18 months Sources of pleasure include sucking, biting, swallowing, playing with lips.
Preoccupation with immediate gratification of impulses. Id is dominant.
Anal 18 months–3 years Sources of sexual gratification include expelling feces and urinat- ing, as well as retaining feces.
Id and ego.
Phallic 3–6 years Child becomes concerned with genitals. Source of sexual pleasure involves manipulating genitals. Period of Oedipus complex (where the father becomes the male child’s rival—uncon- sciously) or Electra complex (a female version of the Oedipus complex).
Id, ego, and superego.
Latency 6–11 years Loss of interest in sexual gratification. Identification with like-sexed parent.
Id, ego, superego.
Genital 11– Concern with adult modes of sexual pleasure, barring fixations or regressions.
Id, ego, superego.
Normal and Abnormal Personality
There are three main routes the individual may take in the course of development. One is shown in Table 8.2. It is the route that would presumably result in a normal personality. A second possibility is fixation, the cessation of development at a given stage, sometimes because of trauma (severe emotional shock) and sometimes because of excessive sexual gratification at that stage. The third possibility is regression, which involves reverting to a previous development stage, again sometimes because of trauma, or perhaps because of insufficient sexual gratification at a later stage.
The behavior of adults who are fixated at a certain stage, or who have regressed to that stage, is related to the forms of sexual gratification characteristic of the stage. Thus oral characters (fixated or regressed at the oral stage) are those who chew their nails, bite their lips, smoke, chew gum, and otherwise exercise their mouths. Anal characters are com- pulsive, orderly, stingy, and perhaps aggressive—these characteristics presumably being related to the pleasure (sexual gratification) associated with the retention and expulsion of feces during the anal stage. Phallic characters are concerned with the immediate satisfac- tion of their sexual urges without regard for the object of their satisfaction: they are sadists and rapists (according to Freudian theory).
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CHAPTER 8Section 8.5 A Psychodynamic Approach: Freud
Defense Mechanisms
In both normal and abnormal development, explains Freud, the id constantly strives for grati- fication. Meanwhile, the superego battles against the id, raising moral and cultural objections to unbridled gratification. And through all this, the ego struggles to find some way of finding the gratification that the id craves, but within the con- straints imposed by the superego.
In trying to compensate for not being able to satisfy all of the id’s urges, the ego often resorts to defense mechanisms. Basically, defense mechanisms are ways of channeling urges and of reinterpreting (and often distorting) reality. The ego is success- ful, explains Freud, when it eliminates or reduces the anxiety that accompanies the con- tinual struggle between the id and the superego. In a sense, these mechanisms are the ego’s attempt to establish peace between the id and the superego so that the personality can con- tinue to operate in an apparently healthy manner. Thus, at one level, defense mechanisms are normal, healthy reactions to the world. What sometimes happens, however, is that the individual comes to rely on them too much. The result may be a dramatically distorted view of self, of others, and of reality, and may be evident in various personality disturbances.
Several dozen distinct defense mechanisms have been described by Freud and his follow- ers. The most common of these are summarized and illustrated in Table 8.3.
Table 8.3 Some Freudian Defense Mechanisms
Mechanism Example
Displacement: Undesirable emotions are directed toward a different object.
A man who is angry at his wife yells at his dog or drives his car unusually aggressively.
Reaction formation: Behavior is the opposite of the individual’s actual feelings.
A woman loves an unobtainable man and behaves as though she dislikes him.
Intellectualization: Behavior motivated by anxiety- provoking emotions is stripped of its emotional meaning.
A football player who enjoys hurting opponents convinces himself he is moved by the desire to win and not by his desire to inflict pain.
Projection: Undesirable feelings or inclinations are attributed to others.
A student who is extremely jealous of another who has received a scholarship convinces himself it is the scholarship winner who is jealous of him.
Denial: Unpleasant, anxiety-provoking aspects of reality are distorted.
A heavy smoker, unable to give up the habit, con- cludes that there is no substantial evidence linking nicotine with human diseases.
Repression: Unpleasant experiences are buried deep in the subconscious mind and become inac- cessible to waking memory.
A person who was sexually abused as a child remembers nothing of the experience.
Anal characters, says Freud, are com- pulsive, orderly, and, like this man, stingy. Unfortunately, our personalities have proven more difficult to classify than Freud’s typology would imply.
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CHAPTER 8Section 8.6 Learning-Based Approaches
Review of Freudian Theory
Freud’s theory is one of the most comprehensive and influential of all psychological theo- ries. It continues to have an enormous impact on psychotherapy. For example, the psy- chology database PsycINFO lists well over 1,000 articles, published in the first decade of this century, that refer to defense mechanisms. In the first 6 months of 2010, it listed more than 200 articles that relate to Freudian theory.
Freudian theory has had a tremendous influence on our attitudes toward children and child rearing. More than anyone else, Freud was responsible for making parents realize how important early experiences can be.
Freudian theory has also had an enormous impact on the development of other theories. However, many of Freud’s students and followers have rejected important aspects of the theory. For many, Freud paints too dark and cynical a picture of human nature: In his view, primitive forces over which we have no control drive us relentlessly toward the sat- isfaction of instinctual urges and bring us into repeated conflict with reality. In addition, the theory is clearly weak from a scientific point of view, based as it is on a limited number of observations collected by a single individual (Freud himself) and not subjected to any rigorous analysis.
In spite of these criticisms, Freud’s work still stands as an immensely rich basis for think- ing about and understanding human personality.
8.6 Learning-Based Approaches
Biological approaches to understanding personality focus on the relationship between inherited predispositions and manifested behavior; psychodynamic approaches are concerned with interactions among competing or cooperating psychic (mental) impulses; learning-based approaches are more concerned with the role of the environment, of social interaction, and of cognitive processes. The unifying theme of learning-based approaches is that much of personality is acquired through experiences rather than genetically deter- mined or influenced.
Behaviorism
As we saw in Chapters 1 and 4, behaviorism provides one explanation for how personal- ity traits might be learned. Some early behaviorists such as John Watson were absolutely convinced that the metaphor of the mind as a blank slate (tabula rasa in Latin) was correct. “Give me the child and my world to bring it up in,” he wrote, “and I’ll make it crawl or walk; I’ll make it climb and use its hands in constructing buildings of stone or wood; I’ll make it a thief, a gunman, or a dope fiend. The possibility of shaping in any direction is almost endless” (Watson, 1928, p. 35).
The clear assumption of behavioristic approaches to personality is that we are born with few genetically determined personality characteristics; what we become is a function of the experiences we have. In other words, personality characteristics are learned.
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CHAPTER 8Section 8.6 Learning-Based Approaches
Skinner was another behaviorist who wholeheartedly accepted the tabula rasa doctrine. He believed that the consequences of our actions shape our behaviors and ultimately determine what we are most likely to do. Hence our environments and not our inherited natures shape our traits. It is the experiences we have that make us brave or fearful, outgo- ing or shy, altruistic or selfish.
Few personality theorists now believe that personality is entirely determined by environ- mental experiences. As Robins (2005) notes, about half of the variability in personality traits seems to be related to genetics. But the other half is clearly shaped by environmental influences. And especially important among these are early social experiences.
Bandura’s Social Cognitive Theory
Bandura’s social cognitive theory, the details of which are included in Chapters 4 and 6, is one of the best-known and most useful learning-based theories that looks at the effects of social experiences.
Observational Learning Much of our learning results from observational learning, explains Bandura—that is, from observing and imitating models. Learning to drive a car, for example, is not a question of classical conditioning, of trial and error, or of reinforcement of emitted behaviors. Instead, we instruct the learner in certain fundamentals, we show her the positions and purposes of various controls, we demonstrate their operation, and we allow her to attempt the task with verbal and sometimes physical guidance. In effect, what has happened is that a number of models have been presented and imitated.
A model is not simply a person doing something that can then be imitated by a learner; it includes all the patterns for behavior that complex soci- eties present to their members, including books, verbal directions, film and cartoon characters, and a variety of other real or symbolic objects. Their prevalence is highly evident, as is their effectiveness.
Western societies present a preponderance of achievement-oriented, assertive, outgoing mod- els for men. Not surprisingly, many males in these societies are achievement-oriented, assertive, and outgoing. In contrast, the Zuni culture presents models of cooperation and self-effacement, and these are the primary characteristics of its mem- bers (Roscoe, 1991).
Manifested personality is highly influenced by context. We can’t easily determine how naturally aggressive this soldier is by observing his behav- ior in war.
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CHAPTER 8Section 8.6 Learning-Based Approaches
It seems clear that manifested personality characteristics are highly influenced by social context. This does not mean that theories based on the notion that there are inherited pre- dispositions toward specific personality traits are incorrect. What it does indicate is that biological predispositions will not necessarily be dominant over social influences.
Reciprocal Determinism A central belief of all learning-based approaches is that our behaviors are strongly influ- enced by their outcomes. But, explains Bandura, what is most important is our under- standing of the relationship between our behaviors and their consequences, and our ability to anticipate consequences. And because we can anticipate consequences, we not only direct our behaviors toward the most desirable ends, but we deliberately arrange our environments to maximize positive outcomes. So, in the end, we affect the environment and it affects us in what Bandura labels triadic reciprocal determinism. Our actions and the environment are two aspects of the triad; our personalities (what we know and feel; our wishes and desires; our inclinations) constitute the third.
Personal Agency Unlike Freud, who described human behavior as moved by instinctive and often uncon- scious forces and warring factions, Bandura insists that we are agents of our own actions. Being agents, he explains, requires intentionality (being able to do what we intend), fore- thought (foreseeing the consequences of our actions), and self-efficacy (having a notion of our likelihood of success).
Relevance of Bandura’s Theory The importance of Bandura’s social learning theory of personality is not that it contributes to the identification of personality traits or to their measurement; nor is it particularly use- ful for understanding the structure of personality or the biological and dynamic forces at play. But it does facilitate an understanding of the manifestation of personality.
Most of the personality traits that have been identified are meaningful only in social interaction. Agreeableness, extroversion, sociability, dependency—these are all qualities of human interaction. They describe typical ways of relating to social realities. Further- more, they are not characteristics that individuals manifest regardless of their imme- diate social context. For example, highly aggressive individuals might well display their aggressive tendencies in athletics and other physical activities where aggression is socially approved; few are likely to display aggression in a church choir or university classroom.
In summary, social approaches to personality highlight the tremendous influence of social customs, traditions, expectations, and situations on the manifestation of personality char- acteristics. They argue that acceptable and unacceptable social behaviors are learned.
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CHAPTER 8Section 8.6 Learning-Based Approaches
Rotter’s Cognitive Approach
In the course of learning socially acceptable behaviors, we learn what to expect when we choose this behavior rather than that one. Expectations, Julian Rotter (1982) explains, guide our behaviors.
Externality-Internality In effect, expectations are beliefs about sources of reinforcement. Basically, claims Rotter, we can have one of two different attitudes toward our behaviors and their outcomes. We can be externally oriented or internally oriented—a notion later borrowed and elaborated by Weiner (2008) in his theory of motivation.
As we saw in Chapter 6, those who are internally oriented tend to take responsibility for the consequences of their actions. They see themselves as being in control; they attribute success or failure to internal factors (ability or effort). Those who are externally oriented believe that they have little control over what happens to them. They attribute success or failure to external factors (luck and task difficulty). Expectations of reward, and behav- iors, will be affected accordingly (Figure 8.8).
Various studies have uncovered a large number of situations where expectations based on locus of control affect behavior. Not surprisingly, those who think they are in control of out- comes (the internally oriented) are less likely to be obese (Adolfsson, Andersson, Elofsson, Rossner, & Unden, 2005); they are more likely to participate in and profit from treatments to counter various delinquent behaviors, including alcoholism (Cavaiola & Strohmetz, 2010); they are more likely to be successful at work and integrate more readily into new social environments (Vonthron & Lagabrielle, 2002); they are less likely to behave aggres- sively toward an intimate partner (Gallagher & Parrott, 2010); they are less likely to have
People’s misfortunes are often the result of bad luck
People’s misfortunes are often caused by the mistakes they make
Success requires getting the right breaks People who are not successful have usually not taken advantage of their opportunities
a b
Figure 8.8
Items similar to those used by Rotter to assess a person’s locus of control. An internally ori- ented person is more likely to select the second statement (b) of each pair.
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CHAPTER 8Section 8.7 Humanistic Approaches
eating disorders (Scoffier, Paquet, & d’Arripe-Longueville, 2010); and they tend to have generally more positive attitudes (Gianakos, 2002).
Personality theorists such as Bandura and Rotter look for regularities in individual deci- sions and beliefs, and they search for ways in which people can be identified on the basis of differences in their dominant modes of functioning. Their theories provide strong indi- cations that important personality differences are evident in learned social interactions and that they reflect our expectations.
8.7 Humanistic Approaches
But surely, the humanists protest, there is more to human behavior and personality than inherited predispositions, basic instincts, warring psychic forces, and learned expecta- tions and beliefs. We need to take into consideration what it means to be human. We need to emphasize the worth and dignity of every individual.
Abraham Maslow’s Self-Actualized Person
Like most humanistically oriented psychologists, Maslow’s principal concerns have been with the development of the healthy person. As we saw in Chapter 6, fundamental to his position is the notion that we are moved by a hierarchy of needs, the lowest of which relate to physiological survival and the highest to the fullest and most desirable blossom- ing of the person. The process of growth is one of self-actualization—of becoming in the most abstract sense of the term. This involves a recognition of what one is, of what one can and should be, and a striving for fulfillment.
Maslow (1970) admits that the concept of self-actualization is extremely difficult to define. It is characterized by the absence of “neurosis, psychopathic personality, psychosis, or strong tendencies in these directions” (p. 150). In addition, self-actualized people “may be loosely described as [making] full use and exploitation of talents, capacities, potentialities, etc.” (p. 150).
Using these rather loose criteria, Maslow’s search for self-actualized people among a group of 3,000 college students yielded only one actualized person and one or two dozen “poten- tials.” Maslow concluded that a fully actualized person is much more likely to be found among older people. He then selected a small number of cases (23) from among his contem- poraries and historical figures. He interviewed them where possible (extremely informally), or read accounts of their lives. Maslow subsequently described some of their personality characteristics: autonomous and independent; highly accepting of themselves and others; tolerant; free of inhibitions; spontaneous and able to enjoy themselves; free of guilt.
Science might shudder to consider that individuals were defined as being self-actualized by Maslow and were then interviewed by him to determine what self-actualized people were really like. The process is only slightly different from deciding that authoritarian people are psychopaths, selecting a group of psychopathic-authoritarian people, and interviewing them to determine whether authoritarian people are really psychopathic. The only surprises possible are those that might arise from errors in selection or in interviewer judgment.
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CHAPTER 8Section 8.7 Humanistic Approaches
Rogers’s Phenomenology
Phenomenology is concerned with the world as it appears rather than as it actually might be. Humanistic positions are typically phenomenological in that their main concern is with the individual at the center of realities that are, in essence, self-created. The argu- ment is that no two people see the world in exactly the same way, and that understanding people requires understanding their notions of the world.
Carl Rogers’s theory of person- ality is well summarized by this abbreviated list of his the- oretical beliefs (Rogers, 1951, Chap. 11):
1. Every individual exists in a continu- ally changing world of which that person alone is the center. The person’s world is thus private, unknown and unknowable by any- one else. As the exis- tential philosophers have pointed out, existence is lonely; it is necessarily always alone.
2. My perception of the world is real. So is yours. We have our separate realities. If we are to understand each other, you must try to understand my world, and I yours.
3. We have one basic ten- dency—actualization. In short, we have an inner, directing need to develop ourselves in Maslow’s sense of the word.
4. The structure of self— notions of I or me— develops as a result of interaction with the environment and, par- ticularly, interaction with others.
Albert Einstein Eleanor Roosevelt
Ralph Waldo Emerson Abraham Lincoln
Maslow defined the actualized personality as being free of defects such as neuroses and as having made full use of all capabilities and talents. He searched far and wide for examples of fully actualized individuals but found only a few, including these four. Although self-actualization may be evident among these historical giants, it’s less easy to detect among plumbers and taxi drivers.
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CHAPTER 8Section 8.8 Measuring Personality Variables
5. Values attached to notions of self are obtained either as a result of direct experi- ence or indirectly. Thus, I can learn that I am good as a result of engaging in good behavior; or I can infer that I am good as a result of having people tell me I am.
6. Most of our ways of behaving are consistent with our notions of self. We tend to engage in behaviors that do not violate our internalized conceptions of what we are like—our values and ideals.
Humanistic approaches do not present theories so much as a renewed emphasis on human worth and dignity. They look more to glorify the importance of the individual, the nature of being, and the sanctity of personal experience than to analyze and dissect in the some- times impersonal laboratories of science. Their impact on approaches to mental health and counseling has been considerable. Carl Rogers’s person-centered therapy continues to be widely applied in therapeutic settings (Cain, 2010).
8.8 Measuring Personality Variables
Say I want to hire somebody and I want to make sure he or she is cooperative, agreeable, not highly neurotic, and not afraid of the dark (the work is carried out in an unlit base- ment); how can I uncover somebody’s personality?
I have four choices, Funder (2007) explains: I can look at life outcomes (whether candi- dates are married, have graduated, what work they have done, whether they sleep in the dark); self-reports (I can ask candidates about themselves, maybe give them question- naires, ask them if they leave their lights on at night); observer ratings (I can ask their friends, families, former teachers, or expert judges what they are like and whether they willingly eat in dark places); or objective tests (instruments designed specifically to mea- sure personality). Objective personality tests are typically described as being projective or nonprojective.
Projective Measures
I might also find out whether my candidates are afraid of the dark by asking them to respond to ambiguous descriptions, pictures, or sounds and trying to find evidence of fear or confidence projected into their descriptions. Projective measures of this kind have been used extensively in personality assessment. The assumption underlying the use of projec- tive tests is that unconscious fears, desires, and other personality traits may be projected in descriptions of stimuli apparently unrelated to the underlying personality characteris- tics. Since these traits are unconscious, the argument goes, they would not ordinarily be revealed in conventional measures of personality.
The Rorschach Among the best known of the projective measures is the Rorschach inkblot test, so called because it presents the subject with 10 stimulus cards with printed figures that resemble elaborate inkblots (Figure 8.9). The scoring procedure is complicated, detailed, and not
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CHAPTER 8Section 8.8 Measuring Personality Variables
well validated, and interpretations of different experts vary a great deal. Furthermore, the relationships of scorer interpretations to the actual behavior of testees has been very dif- ficult to establish, although there is evidence that it can be used to discriminate between psychotic and nonpsychotic populations (Wood et al., 2010). It continues to be one of the most widely used personality measures in clinical practice (Sendin, 2010).
The Thematic Apperception Test Another well-known projective test is H. A. Murray’s (1938, 1943) thematic apperception test (TAT). It consists of 30 black-and-white pictures showing people in various situations and asks subjects to tell a story suggested to them by the pictures. Clinicians often use the TAT as a way of gaining insight into the subject’s fantasies. Although the test does not measure specific personality characteristics, it may be highly suggestive of preoccupations, fears, unconscious needs and desires, personal relationships, and related themes. It is widely used in clinical practice as well as in research (Teglasi, 2010). For example, it has been the basis of many investigations of need achievement, with scorers looking for achievement- related themes in subjects’ descriptions of the pictures. It has also been used to look at the concerns and interests of highly creative children (Garces-Bacsal, 2010).
Figure 8.9
The Rorschach inkblot test. Subjects are shown 10 such stimuli and asked what the stimuli look like to them and why.
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CHAPTER 8Section 8.8 Measuring Personality Variables
Nonprojective Measures
There are hundreds of paper-and-pencil or computer-based personality tests, usually referred to as scales or inventories. Scales measure specific dimensions of personality (sociability, neuroticism, and so on); inventories are more inclusive. Typically, inventories consist of a number of different scales and yield a profile of personality characteristics.
The NEO-PI-R The Neuroticism Extraversion Openness Personality Inventory, Revised (NEO-PI-R) (Costa & McCrae, 1992) is an inventory designed specifically to assess the Big Five personality factors (conscientiousness, agreeableness, neuroticism, openness, and extraversion). It is available in a longer 240-item format or in a shorter 60-item inventory. Items are presented on what is called a Likert scale—that is, on a scale where the responder selects an option ranging from strongly disagree to strongly agree.
Research indicates that this personality inventory has relatively high reliability (consis- tency) and validity in terms of its usefulness for predicting outcomes such as adjustment to career requirements. For example, scores on the NEO-PI-R correlate well with job suc- cess (Denis, Morin, & Guindon, 2010). It has been translated into many different languages and is reportedly useful across many cultures (Ortet et al., 2010; Plaisant, Courtois, Reveil- lere, Mendelsohn, & John, 2010).
The MMPI-2 One of the best-known, most rigorously developed, and most widely used personality inven- tories is the Minnesota Multiphasic Personality Inventory-2 (MMPI-2). There are various forms of this test, which is normally computer scored. Ordinarily, it yields measures on a wide number of dimensions. Ten of the original scales are clinical scales. Closely related to these are newer Restructured Clinical (RC) scales. These clinical scales provide scores on dimensions such as depression, hypochondriasis, hysteria, paranoia, schizophrenia, and social intro- version. Some scales are validity scales: They provide indications of the extent to which an individual’s responses may be considered reliable and valid. In addition, there are various supplementary scales that measure things such as proneness to substance abuse and anxiety.
MMPI-2 items were first developed with groups of individuals who had been clearly diagnosed with disorders such as hypochondriasis, depression, or psychopathy. Scores obtained by these groups were then compared to scores obtained by a normal “control” group, and items were selected on the basis of how well they discriminated between groups. If, for example, hypochondriacs always responded in one way to 10 items, and controls always responded differently, these 10 items would then make up the hypochon- driasis scale. It would then be possible to identify people who respond in the same way as hypochondriacs by looking at their scores on that scale.
In many ways, the MMPI-2 is a masterpiece of objective test construction. Evidence sug- gests that it is useful in making discriminations among groups of people and in prelimi- nary diagnosis of abnormal behavior—which is the purpose for which it was designed. It appears to have impressive validity when used for that purpose. However, it is also often
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CHAPTER 8Main Points
used for personnel assessment or as a screening tool with presumably normal individu- als—purposes for which it has questionable validity. Indications are that it remains an extremely powerful tool for identifying emotional and mental disorders (Caldwell, 2006). Few instruments have been used more widely in psychological diagnosis, and few have stimulated more research.
Some Cautions
Although personality inventories and other assessment devices have proven useful in a number of situations, both practical and theoretical, it cannot yet be argued that any spe- cific personality trait can be measured with unquestioned validity and reliability. Results obtained from different inventories for the same individual are sometimes different, and not all predictions made on the basis of diagnostic instruments have been entirely reliable. For these reasons, interpretation of test scores requires both restraint and wisdom. Tests such as these can be dangerous in the hands of those who are not fully aware of their weaknesses. Users must constantly bear in mind that the stability of personality characteristics is still a matter of debate. A test that reveals an individual to be tense does not establish that anxiety is a pervasive and predominant personality characteristic in that person. Personality tests mea- sure mood, fatigue, feelings of happiness or dejection, and a variety of other affective states. And we know from our private experience that none of these is necessarily permanent.
Main Points 1. Personality: Personality is defined as an individual’s stable characteristics,
including habits, preferences, weaknesses, strengths, moral attributes, and cus- tomary ways of thinking, feeling, and behaving. The Barnum effect labels our tendency to believe vague generalities about ourselves.
2. The Types and Traits Approach: A personality trait is a specific quality that dif- ferentiates among different individuals (for example, good-hearted or selfish); types are clusters of related traits. The Big Five personality factors are five inde- pendent personality dimensions, each of which can range from very high to very low: conscientiousness, agreeableness, neuroticism, openness, and extraversion.
3. Biological Approaches: Biological approaches emphasize the genetic underpin- nings of personality. Historical biological approaches include Sheldon’s sugges- tion that body type (ecto-, endo-, and mesomorph) is strongly associated with different temperaments. Eysenck’s biological approach holds that inherited dif- ferences in nervous system activity underlie the two main dimensions of person- ality, extraversion and introversion, as well as a third dimension, psychoticism. Recent approaches use genomics and neuropsychology to look for genetic and neurological structures and functioning underlying personality differences.
4. A Psychodynamic Approach: Freud: Psychodynamic approaches look at the interaction of basic inherited tendencies with physical and social reality to explain personality. In Freud’s system, sexual and survival urges (id) often drive us in directions incompatible with social reality and conscience (superego). This leads to conflict that our conception of reality (ego) mediates and tries to resolve. Objects of sexual gratification progress from oral through anal, phallic, latent,
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CHAPTER 8Main Points
agreeableness
archetypes
Barnum effect
Big Five factors
conscientiousness
defense mechanisms
ectomorphs
ego
Electra complex
endomorphs
eros
extraversion
factor analysis
fixation
genome
genomics
id
identification
introversion
libido
mesomorphs
neuroticism
Oedipus complex
openness
personality
phenomenology
projective approach
psychodynamic theory
regression
superego
thanatos
trait
type
and genital as we develop. Fixation and regression are two unhealthy possibili- ties, as is overreliance on defense mechanisms.
5. Learning-Based Approaches: These approaches look at the role of the social and physical environment in determining personality. Behavioristic approaches describe how personality traits might be shaped and conditioned. Bandura’s social cognitive theory describes personality development in terms of the effects of observation and the reciprocal determinism at play in person-behavior- environment interactions. It emphasizes the extent to which we are agents of our actions, anticipating and intending their outcomes, and estimating our likelihood of success in our endeavors (self-efficacy). Rotter’s expectancy theory explains how locus of control (external and internal orientation) affects our personalities as reflected in our choice of behaviors.
6. Humanistic Approaches: Both Maslow and Rogers describe the development of human potential as the highest goal. They emphasize healthy human functioning and the uniqueness and worth of the individual.
7. Measuring Personality Variables: Personality variables may be evident in life outcomes and observer ratings. They can also be measured with projective tests such as the Rorschach and TAT (where the individual reveals unconscious traits in responding to ambiguous stimuli), or with nonprojective written tests like the NEO-PI-R (which measures the Big Five personality types) and the MMPI-2 (which is designed mainly to measure personality disorders).
Study Terms
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9
Psychological Disorders and Therapies
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • What are examples of ethnic psychoses? • How are the terms insanity and mental disorder differentiated? • What are the identifying characteristics of the principal models used to understand
mental disorders? • What are symptoms of the principal anxiety disorders? • What are the identifying characteristics of impulse-control disorders in childhood? • What are the most common mood disorders? • How are bipolar disorder and schizophrenia different? • What are the main sexual and gender identity disorders? • What are the identifying characteristics of different personality disorders? • What are the main approaches to therapies for mental disorders?
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CHAPTER 9Psychological Disorders and Therapies
“‘But I don’t want to go among mad people,’
Alice remarked.
‘Oh, you can’t help that,’ said the Cat.
‘We’re all mad here. I’m mad. You’re mad.’
‘How do you know I’m mad?’ said Alice.
‘You must be,’ said the Cat, ‘or you wouldn’t
have come here.’” —Lewis Carroll,
Alice’s Adventures in Wonderland
Chapter Outline
9.1 Historical and Current Views of Mental Disorders
Historical Views of the Causes of Mental Disorders
Current Definitions and Models Classifications of Disorders The Most Common Disorders
9.2 Anxiety Disorders Panic Attacks Generalized Anxiety Disorder Phobic Disorders Obsessive-Compulsive Disorders Posttraumatic Stress Disorder
9.3 Impulse-Control Disorders Usually First Diagnosed in Children
Aggression-Based Impulse-Control Disorders Conduct Disorder Attention Deficit Hyperactivity Disorder Other Impulse-Control Disorders
9.4 Mood Disorders Major Depressive Disorder Bipolar Disorder Dysthymic Disorder
9.5 Substance-Related Disorders Substance Use Disorders
9.6 Other Axis I Disorders Dissociative Disorders Psychotic Disorders Sexual and Gender Identity Disorders Somatoform Disorders
9.7 Axis II Personality Disorders
9.8 Therapies Medical Therapy Insight Therapy Learning-Based and Cognitive Therapy The Effectiveness of Therapies
How, indeed, can we recognize madness (which, incidentally, is not a term commonly used in psy- chology; mental disorder or emotional disorder is more common). And is it contagious? Is Alice justified in wanting to avoid mad people?
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
9.1 Historical and Current Views of Mental Disorders
In Tim Burton’s movie of Alice in Wonderland, madness takes weird and unexpected forms. “You used to be much more . . . ‘muchier,’” the Mad Hatter says to Alice. “You’ve lost your muchness.” In Wonderland, perhaps if you have enough “muchness,” you will not be mad?
Wonderland is not the only place that has its own special forms of madness. Many cul- tures and historical periods have had theirs, too (Conrad & Schneider, 1992; Farina, 1976). For example, for reasons that are still unclear, 18th-century Europe was swept by a wave of hysterical disorders. Their common symptoms were paralysis, deafness, blindness, and other physical incapacities. Hysteria is no longer used as a term for mental disorders, hav- ing been replaced by the label conversion disorders.
A disorder specific to the 19th century is pibloktoq, an ethnic psychosis observed by Admiral Peary among Eskimo women (Parker, 1962). Ethnic psychoses are mental disor- ders limited mainly to one or a few ethnic or cultural groups. The primary symptoms dis- played by people with pibloktoq included a short period of intense mania during which victims ran about in extreme excitement, singing, shouting, and tearing off their clothes— which is not entirely sensible in Arctic regions. Subsequently, victims might weep, lose consciousness, or fall asleep and later awaken apparently normal.
Windigo (witigo or wihtigo) is another pre-20th-century ethnic psychosis found among native North American tribes—mainly the Canadian Ojibway and Chippewa—where victims were “bewitched” and turned into cannibals (Brightman, 1988). The condition appeared with warning signals such as nausea, vomiting, and increased anxiety. Many suffering from these initial symptoms were afraid they would kill and eat a friend, and might even ask to be killed themselves before they became completely mad.
A relatively rare, culture-bound disorder is the condition called amok (whence our expres- sion “to run amok”), most prevalent in Malaysia, the Philippines, and Southeast Asia. Victims are suddenly possessed by overpowering aggressive and violent urges, and run about destroying property and trying to kill anyone in sight. The condition sometimes lasts until the victims manage to kill themselves, knock themselves senseless, or drop into a coma. Amnesia covering the period of being “amok” is common.
A disorder that affects Latinos in Mexico, South America, and elsewhere is susto (the word means “fright” in Spanish) (Rubel, 1964). It appears when an intensely frightening (traumatic) episode convinces victims (mainly women) that their soul has left their body. Symptoms may include nervousness, insomnia, despondency, muscle tics, and diarrhea. Traditional healers are often consulted in an effort to reunite the soul with the body.
Of special interest to students is brain fag, which, thankfully for North Americans, is found almost exclusively in West Africa. It is triggered by prolonged periods of intense study resulting in difficulty concentrating, insomnia, anxiety, and depression (Katona & Robertson, 2005).
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
Historical Views of the Causes of Mental Disorders
We too in North America and Western Europe have our own forms of mental disorders, the most obvious of which is anorexia nervosa. As we saw in Chapter 6, it is a disorder linked to our cultural standards in the same way as so many culture- specific disorders are linked to spiritual and reli- gious beliefs.
Not surprisingly, many ancient human cultures attributed madness to the work of gods or to possession by evil spirits. Windigo and susto are two examples. Witches were often thought to be responsible. As a result, in 1484, Pope Inno- cent VIII issued a papal bull (edict) exhorting all clergy to search constantly for witches. Two well-intentioned monks subsequently compiled a manual documenting the existence of witches and explaining how they might be hunted. They described the various signs that could be used to prove that a suspect was a witch. Most impor- tant among these were the red marks sometimes left by the devil’s claw on the witch’s skin, and the fact that witches do not sink when bound and tossed into water. In addition, this “divinely inspired” manual described the many methods of torture that might be used to convince the devil that a confession would be in order. Those found guilty of being witches were generally executed publicly. By around 1700, an estimated 40,000 to 100,000 witches had been executed in Europe and North America (Levack, 2006).
Current Definitions and Models
Insanity is a legal term, defined by law and deter- mined by a court in consultation with mental health experts. Hence it is a legal issue that might determine whether a convicted person is respon- sible for a crime. Individuals found not guilty by reason of insanity are frequently provided with treatment rather than punishment.
The term insanity is seldom used in medicine and psychology, although it has been retained by the courts. The terms abnormality, mental illness,
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Different forms of madness are often culture- and era-specific. This man suffers from what he suspects is brain fag, a West African disorder that fol- lows prolonged periods of intense study and results in insomnia, dif- ficulty concentrating, and depression. The woman is anorectic—an uncom- mon disorder outside North America and Western Europe.
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
personality disorders, psychological disorders, emotional disorders, mental disorders, or other more specific descriptions are preferred.
How we look at and define mental disorders depends greatly on the models we use. In one sense, models are guides or ways of looking at things. Models tell us what to look for when we’re trying to understand, explain, and define what we mean by mental disorders. Among the various models used for this purpose are the statistical, the medical/biological, the behavioral, the cognitive, and the psychodynamic.
The Statistical Model One way of determining whether a behavior is abnormal is in relation to the prevalence of the behavior in the general population. According to this model, those whose behaviors or personality traits violate social norms and are therefore demonstrably different from the majority are abnormal in a statistical sense (Figure 9.1). Significant departure from nor- mality with respect to emotional functioning, social behavior, perception, and so on may be directly related to mental health. Deviance is evident in behaviors and characteristics that have low frequency. To be afraid of red dirt is deviant because most people are not afraid of red dirt. But if you live where everybody knows red dirt is toxic, not being afraid of it might be abnormal.
The statistical model is useful in that it provides an objective method for identifying abnormal behavior. For example, intellectual disabilities (still often called mental retar- dation) are defined as a significant departure from average intellectual and adaptive
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abnormality normality
The Great Average
arbitrary
abnormality
The Great Average
Figure 9.1
The statistical model of abnormality. According to this model, being significantly different from other people is abnormal.
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
functioning. Similarly, disorders such as autism, Asperger’s syndrome, and specific learning disabilities are all defined in terms of behaviors that are not age-appropriate in a statistical sense.
Medical/Biological Models Medicine deals with physical (organic) malfunctions that are due to injury, infection, chemi- cal imbalances, genetics, or other causes and that can often be treated surgically or chemically. The medical view of psychological malfunction is analogous. Accordingly, psychological abnormality is sometimes seen as a disease or illness caused by internal factors (infection, system malfunction, or genetic causes) and amenable to the same sorts of treatment that might be employed for organic malfunctions. The finding of high heritability of disorders such as bipolar disorder and schizophrenia suggests that, at least for these diseases, there may often be an underlying genetic cause (Walsh, McClellan, & McCarthy, 2008). For exam- ple, there is evidence that as much as one third of the risk of acquiring schizophrenia is due to identifiable genetic variations (Massachusetts General Hospital, 2009).
The most obvious advantage of the medical models is that they encourage the search for specific organic causes of various disorders and suggest means of dealing with them. They look not only at genes as a possible cause, but also at neurological functioning and especially at the role that various neurotransmitters play. The development of highly effective drug therapies for disorders such as depression is related directly to informa- tion that neuroscience provides about the role of neurotransmitters in areas of the brain involved in emotion.
Behavioral Models The principal difference between medical models of abnormality and the behavioral mod- els lies in their explanations of causes. Whereas medical models ascribe abnormality to internal causes such as disease, injury, or chemical imbalances, behavioral models claim simply that abnormal behavior is learned just as is any other behavior. Most behavioral models are premised on conditioning theories, or variations thereof, and concentrate principally on manifestations of abnormal behavior without paying much attention to supposed causes. Whereas medical models lead to treatments designed to eliminate the causes of malfunctioning, behavioral models concentrate instead on “unlearning” unac- ceptable behavior and learning (or relearning) more “normal” forms of behavior.
Cognitive Models The cognitive interpretation of psychological disorders revolves around the notion that these disorders involve cognitive problems that are often expressed in distortions of real- ity (Beck, 2008). Patients view themselves as worthless, unhealthy, and unhappy, have unrealistic appraisals of their future, and react inappropriately. Distorted views of reality are, in fact, one of the principal characteristics of the more serious mental disorders.
Contemporary cognitive models also take into account the interaction of genetic and neurological events with cognitive problems. For example, neuropsychological research
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
provides a great deal of evidence that an overactive amygdala may be associated with a higher risk of depression (Gaffrey et al., 2011). And genomics research (research on the contributions of genes) has discovered a variety of links between genome (genetic complement) and a variety of disorders, including bipolar disorder (for example, Choi et al., 2011).
Although the cognitive model considers these genetic and neurological causes, their emphasis is on the cognitive (intellectual) distortions that underlie maladaptive behavior. For example, in this view, overreaction to stress may be genetically based, but it is medi- ated by cognitive distortions. Accordingly, therapies are directed toward altering subjects’ perceptions of the world and of themselves—in other words, toward changing cognitions.
Psychodynamic Models As we saw in Chapter 8, the psychodynamic model describes how our basic libidinal urges (id) are continually being impeded by our immediate circumstances (ego) as well as by the fact that society does not permit unbridled expression of sexuality or aggression (super- ego). The result of this conflict is anxiety, which we try to reduce in various ways including through defense mechanisms.
If the anxiety is sufficiently severe, or if there is an overreliance on defense mechanisms, the result may be mental disorders of various kinds. Also, if the individual stays stuck in a developmental stage or regresses back to an earlier stage, development is said to be abnormal.
Which Model? These various models show how complicated this part of the human puzzle is. It is not possible to say that one of the models is correct and the others not. Nor is it possible to state categorically that one is more useful than any other. Each leads to a different view of mental disorders; and each leads to different forms of intervention or treatment.
The statistical model is useful in providing a relatively objective means of identifying bizarre, unconventional behavior, although its value in increasing our understanding of abnormal behavior or our ability to deal with it is clearly limited.
Medical models are valuable in providing methods for identifying and describing mal- functions, and often in providing specific treatments for them, as is clear in the wide- spread use of medications that are often highly effective treatments for a variety of mental disorders.
The principal contribution of the behavioral and cognitive models has been the devel- opment of systematic learning-based therapies that have been highly effective in many situations.
Psychodynamic approaches, despite their historical influence, tend to be imprecise and speculative. The various models of mental disorders are summarized in Table 9.1.
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
Table 9.1 Models of Mental Disorders
Model Abnormality What the Therapist Looks For Therapeutic Approach
Statistical A rare behavior Uncommon behavior in a statis- tical sense
None
Medical/Biological System malfunction Organic, systemic, or genetic basis
Drug therapy, surgery, electroconvulsive shock therapy
Behavioral Learned behavior Symptoms, not causes Learning therapies (such as behavior modification)
Cognitive Inappropriate cog- nitions (beliefs, thoughts, perceptions)
Irrational or inappropriate beliefs about self or others
Attempts to change cognitions, sometimes through learning therapies
Psychodynamic Psychic conflicts, anxiety
History, relationships Psychoanalysis
A Definition Most of the difficult concepts in psychology cannot easily be defined in a single sentence or paragraph. This text requires many thousands of words to define psychology and lay out the pieces of the human puzzle that have been gathered so far. Still, mental disorder can be defined in one sentence: In general, a mental disorder is a pat- tern of behavior or thought that is not reasonable or easily understood and that is associated with “clinically significant” distress or impairment in coping with the environment.
This definition is implicit in the descriptions and classifications of mental disorders provided by the American Psychiatric Association. There, each of the many different disorders is defined sepa- rately, mainly in terms of the nature, onset, and implications of characteristic symptoms.
Classifications of Disorders
The Diagnostic and Statistical Manual of Mental Disorders IV Text Revision (DSM-IV-TR) of the
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Different models of mental disorders provide different explanations and different treatments. Most agree that mental disorders involve problems in coping with the world and, as in the case of the boy shown here, significant distress and unhappiness.
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
American Psychiatric Association (2000) presents classifications of mental disorders in terms of major and minor categories and is used extensively in psychiatric diagnosis.
DSM-IV-TR presents 16 separate major categories plus 2 others to include conditions that do not readily fall under other classifications. It has been revised regularly, often adding new disorders (for example, anorexia, bulimia, and binge eating disorder) and removing others (for example, homosexuality).
One of the important criteria for most DSM-IV-TR categories of mental disorder is that the condition present “clinically significant distress or impairment” in important areas of functioning. DSM-IV-TR classifications are summarized in Table 9.2.
Table 9.2 Major Categories of Mental Disorders According to DSM-IV-TR of the American Psychiatric Association
Mental Disorder Example
Disorders Usually First Diagnosed in Infancy, Childhood, or Adolescence
Mental retardation; autism
Delirium, Dementia, and Amnestic and Other Cognitive Disorders
Alzheimer’s; persistent memory impairment
Mental Disorders Due to a General Medical Condition
Sexual dysfunction due to a general medical condition
Substance-Related Disorders Substance abuse; alcohol-related disorders
Schizophrenia and Other Psychotic Disorders Paranoid disorder
Mood Disorders Major depressive episode; manic episode
Anxiety Disorders Panic attack; agoraphobia
Somatoform Disorders Hypochondriasis
Factitious Disorders Intentionally produced symptoms of illness
Dissociative Disorders Dissociative identity disorder (multiple personality)
Sexual and Gender Identity Disorders Hypoactive sexual desire; erectile disorder
Eating Disorders Anorexia; bulimia
Sleep Disorders Narcolepsy; insomnia
Impulse-Control Disorders not Elsewhere Classified
Kleptomania; pyromania; pathological gambling
Adjustment Disorders Adjustment disorder with depressed mood
Personality Disorders Antisocial or paranoid personality disorder
Other Conditions that may be a Focus of Clinical Attention
Medication-induced movement disorder
Additional Codes Unspecified mental disorder
DSM-IV-TR presents well-defined criteria for diagnosing disorders. Clinicians do not need to rely on their interpretation of what is meant by a classification; they need only determine whether certain symptoms are present and apply relatively definite rules for making the diagnosis.
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
DSM-IV-TR asks that the patient be diagnosed and evaluated on five separate dimen- sions, or axes, and provides specific rules for assigning codes on all five dimensions. This multiaxial approach allows clinicians to arrive at a more comprehensive evaluation of the patient’s level of functioning in various areas.
The first two axes include all the diagnostic classification provided by DSM-IV-TR. Axis I describes clinical symptoms related to significant impairment in functioning. It includes adjustment disorders, anxiety disorders, and pervasive developmental disorders. Person- ality disorders and mental retardation are coded on Axis II.
Axis III is for coding physical and medical problems that might be important in under- standing and treating relevant mental disorders. For example, brain injuries or HIV/AIDS might significantly impact other classifications. A clinician would certainly find it useful to know that a depressed patient has recently been diagnosed with a heart condition.
Axis IV reflects the presence and severity of stress in the patient’s recent history. DSM-IV- TR provides nine codes and descriptive terms for “psychosocial stressors,” ranging from “none” and “minimal” to “extreme” and “catastrophic.” Catastrophic stressors would include events such as multiple family deaths, concentration-camp experience, or a dev- astating natural disaster (see Table 9.3).
Table 9.3 Psychosocial Stressors That Can Impact Mental Health Coded on Axis IV, DSM-IV-TR
Type of Stressful Problem Example
Related to Primary Support Group Death of family member; divorce; remarriage; sexual or physical abuse; family discord
Related to Social Environment Death of a friend; discrimination; adjustment to major transition such as retirement; adjusting to new culture
Educational Academic problems; discord with teachers; illiteracy
Occupational Unemployment; stressful job schedule; job change
Economic Poverty; insufficient welfare
Housing Homelessness; unsafe neighborhood; discord with neighbors
Health Care Access Inadequate health care; lack of health insurance
Legal System/Crime Arrest; incarceration; civil litigation; victim of crime
Other Psychosocial and Environmental Natural disasters; war; discord with nonfamily caregivers
Axis V describes the patient’s current level of functioning and the highest level of function- ing during the previous year. Patients may be described in terms ranging from superior (“usually effective functioning in a wide range of activities and relationships”) to grossly impaired (“unable to function in almost all areas”). Clinical experience and research have
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CHAPTER 9Section 9.1 Historical and Current Views of Mental Disorders
shown that prognosis for recovery is closely related to how well-adjusted the patient was before diagnosis.
The DSM-IV-TR is widely used. Such a detailed classification system is enormously useful in enabling researchers and clinicians to communicate and to understand what it is they are studying and treating. It provides a common language for describing mental disorders and a common set of criteria for identifying them.
The Most Common Disorders
A survey of mental disorders in the United States reveals that the most commonly diag- nosed DSM-IV-TR mental disorders are anxiety disorders, followed by impulse-control disorders, mood disorders, and substance-abuse disorders (Kessler et al., 2005; Figure 9.2). When nicotine dependence is included among substance-abuse disorders, it becomes the most frequently diagnosed disorder, at 35 percent (National Comorbidity Survey Replica- tion (NCS-R) (2010).
Of these disorders, anxiety and impulse-control disorders appear earliest at a median age of 11; substance-use disorders, at age 20; and mood disorders are the latest to appear, at a
289
P er
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if et
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An y d
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0%
40%
50%
45%
30%
35%
20%
25%
10%
5%
15%
Figure 9.2
The four most commonly diagnosed mental disorders in America, based on a sample of 9,282 English-speaking participants over age 18. Based on data reported by Kessler et al., 2005.
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CHAPTER 9Section 9.2 Anxiety Disorders
median age of 30 (Kessler et al., 2005; Figure 9.3). We look at these most common classes of disorders before looking at related therapies.
9.2 Anxiety Disorders
A wide variety of disorders, initially labeled neuroses by Freud, are characterized by anxiety. Anxiety is among the most devastating and the most baffling of human emo- tions. It can range from mild trepidation to acute terror and can occur in response to a wide variety of situations, or sometimes without any apparent provocation. In many cases it is both natural and normal; but sometimes it is maladaptive and irrational, and is the basis of a number of disorders.
Panic Attacks
A relatively common anxiety disorder involves recurring episodes of very intense fear and anxiety, often accompanied by physical symptoms such as shortness of breath and heart palpitations. These panic attacks occur for no apparent reason. Victims often feel they might be having a heart attack or that they’re in danger of fainting or even dying. In some individuals, attacks occur only once or twice. Those who suffer from recurrent and persistent panic attacks are diagnosed as suffering from panic disorder. It is not uncom- mon for patients suffering from other mental disorders to also suffer from panic attacks (Ulas, Polat, Akdede, & Alptekin, 2010).
290
M ed
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An y d
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0
30
35
20
25
10
5
15
Figure 9.3
Median age of onset for the four most commonly diagnosed mental disorders in the United States. Based on Kessler et al., 2005.
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CHAPTER 9Section 9.2 Anxiety Disorders
Panic attacks are relatively common, affecting an estimated 10 percent of the population (Panic Disorder, 2010). Among well-known people who have reportedly suffered panic attacks are Sig- mund Freud, Kim Basinger, Tom Cruise, Donny Osmond, Princess Diana, Johnny Depp, and many others (Famous People Affected by an Anxiety Disorder, 2011).
Generalized Anxiety Disorder
Generalized anxiety disorder is marked by gen- eral rather than episodic subjective sensations of anxiety in the absence of specific situations or objects that might be associated with anxiety reactions. The hallmark of this disorder is worry. Individuals suffering from generalized anxiety, sometimes termed free-floating anxiety, recognize themselves as being predominantly tense, ner- vous, and fearful and cannot associate their anxi- ety with anything specific. Generalized anxiety is not marked by the same degree of terror and sensation of impending doom that is the hallmark of a panic attack.
Generalized anxiety disorder is often a debilitating disease that is present in 3 to 5 percent of the population (Wittchen, 2002). It appears to be clearly linked to increased susceptibil- ity to a variety of physical diseases, including auto-immune disorders such as rheumatoid arthritis, lupus, celiac disease, and many others (Vieira et al., 2010). It is also highly predic- tive of other anxiety disorders (Katja, Pine, Lieb, & Wittchen, 2010).
Phobic Disorders
Phobias are intense, irrational fears, recognized by the person as unreasonable, and often leading to avoidance of certain situations. These disorders are typically chronic and can be distinguished in terms of the objects or situations that bring them about.
Agoraphobia Literally, agoraphobia means fear of open or public places. It manifests itself as severe anxiety related to places or situations from which departure or return home may be dif- ficult and, often, avoidance of such places. Subjects may experience anxiety at the thought of leaving home or when traveling alone, being apart from friends, or being in strange places. Agoraphobia is often associated with serious personal distress. In extreme cases, subjects may become completely “house-bound” for prolonged periods.
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The most commonly diagnosed mental disorders are anxiety disorders. Drug therapy is currently the treatment of choice.
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CHAPTER 9Section 9.2 Anxiety Disorders
The prevalence of agoraphobia is uncertain, although some estimates suggest that between 3 and 5 percent of the U.S. population may have the disorder (Kessler, Ruscio, Shear, & Wittchen, 2008). Many people who experience panic attacks later develop agoraphobia. The disorder is seen more frequently in women than in men and most often begins in ado- lescence or early adulthood, although it may occur considerably later.
Social Phobias Social phobia involves fear of social situations—that is, fear of situations in which the individual is exposed to judgment of others. Its most common manifestations include avoidance of social situations and of public behaviors such as speaking formally to a group. Fear of using public washrooms, eating in public, appearing at certain social gath- erings, and writing or performing in public are other manifestations of social phobia.
Because social phobias often lead the individual to adopt a lifestyle and occupational role that don’t demand a great deal of social contact, thus permitting adequate adjustment and functioning, relatively few people seek clinical help for this disorder.
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Acrophobia Heights
Specific phobias Feared object or situation
Algophobia Pain
Mysophobia Germs
Hydrophobia Water
Claustrophobia Being enclosed
Agoraphobia Open places
Anthropophobia People
Thanatophobia Death
Ochlophobia Crowds
Ophidiophobia Snakes
Monophobia Being alone
Zoophobia Animals
Nyctohobia Darkness, night
Arachnophobia Spiders
Figure 9.4
Some common and uncommon specific phobias. Most phobias make some sort of evolutionary sense. Snake and spider phobias are relatively common; fear of the moon or of brussel sprouts, not so much.
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CHAPTER 9Section 9.2 Anxiety Disorders
Specific Phobias Specific phobias include the variety of other specific fears that are not agoraphobic or social. Some of the most common phobias are listed in Figure 9.4.
The criterion for a phobia is simply that the fear be irrational, completely out of propor- tion to the potential danger of the feared object or situation, and not shared by a signifi- cant number of other people. It is interesting to note, however, that human phobias tend to be limited to a number of common situations, most of which imply some sort of danger. Thus, although very few people have furniture or vegetable phobias, a much larger num- ber are afraid of open spaces, heights, closed spaces, insects, snakes, and darkness.
Obsessive-Compulsive Disorders
Obsessive-compulsive disorders are defined by the presence of recurring thoughts or impulses that appear irrational to the person having them (obsessions) and/or behaviors that are not perceived as the result of the individual’s wishes but that give rise to intense urges to engage in them and result in anxiety when they are resisted (compulsions). Thus, a compulsion is a behavior and an obsession is a thought. Both obsessions and compulsions are perceived as incompatible with the individual’s nature, but neither can easily be resisted.
The most common obsessions revolve around cleanliness, fear of germs and of dirt, and fear of thinking evil thoughts and feeling guilty. They also sometimes take the form of repetitive thoughts of violence, accompanied by considerable fear of engaging in some highly undesirable behav- ior. Alternatively, obsessions may be marked by perpetual indecision and doubting which can be severe enough to prevent reaching any decision.
Compulsions typically involve a strong impulse to repeat some senseless and meaningless act over and over again (for example, checking drawers and locks or touching certain objects repeatedly). They are also often centered on washing and cleansing rituals. Less commonly, they might take the form of hoarding—as in the case of the man who had more than 100 cats in his home. And one paranoid dog (Gerson, 2010). Evidence sug- gests that about 1 percent of the adult U.S. popu- lation can be classified as obsessive-compulsive (National Institute of Mental Health, 2011).
Posttraumatic Stress Disorder
Mental disorders that appear following exposure to an extremely traumatic event—such as war, rape, or a horrendous accident—sometimes take
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Macbeth, Act V, scene 1, in which Lady Macbeth, after murdering Duncan, says, “Yet, here’s a spot.” And this after implor- ing, “Out, damned spot! Out, I say. All the perfumes in Arabia will not sweeten this little hand.” Compulsions often involve cleaning rituals. Sometimes they take the form of collecting and hoarding.
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CHAPTER 9Section 9.3 Impulse-Control Disorders Usually First Diagnosed in Children
the form of posttraumatic stress disorder (PTSD). Symptoms may include flashbacks or nightmares during which the individual reexperiences the event. PTSD is often marked by sleep disturbances, anger and aggression, numbing/avoidance, hypervigilance, and significant impairment in social functioning. Compared with other military personnel, alcohol-related disorders are twice as likely for veterans who meet the criteria for PTSD (Jakupcak et al., 2010).
Estimates of the prevalence of PTSD vary widely. One study that looked at the results of 19 different investigations that had attempted to determine the prevalence of PTSD among veterans returning from Iraq found estimates ranging from a low of 1.4 to an astounding 31 percent (Sundin, Fear, Iversen, Rona, & Wessely, 2010).
9.3 Impulse-Control Disorders Usually First Diagnosed in Children
Almost one in three people meet the criteria for diagnosis of an anxiety disorder at some point in their lives. Median age of onset is surprisingly young, at age 11—meaning that half of all those diagnosed with an anxiety disorder will be diagnosed before that age.
Impulse-control disorders, which are primarily childhood disorders, are almost as fre- quent as anxiety disorders—approximately one in four people. They manifest at about the same age (Figures 9.2 and 9.3). Impulse-control disorders are marked by failure to resist an impulse to engage in a behavior that is harmful either to the person or to others. They include a range of often aggressive behaviors.
Aggression-Based Impulse-Control Disorders
Intermittent explosive disorder is marked by the repeated failure to resist aggressive impulses. Children diagnosed with this disorder have typically engaged in a number of excessively violent acts against people or property, or both. As adults, they are at higher risk of aggression in their romantic relationships (Murray-Close, Ostrov, Nelson, Crick, & Coccaro, 2010).
Another aggression-based impulse-control disorder is oppositional defiant disorder. It is characterized by a pattern of hostile, disobedient, defiant behavior toward author- ity figures. The disorder is sometimes apparent in children given to violent temper tan- trums and persistent negative moods. Bullying, stealing, and vandalism are other possible symptoms.
Conduct Disorder
Conduct disorder, which is often preceded by oppositional defiant disorder, is a disorder that begins in late childhood and often becomes more severe in adolescence. A related disorder among adults is antisocial personality disorder.
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CHAPTER 9Section 9.3 Impulse-Control Disorders Usually First Diagnosed in Children
Conduct disorder is far more common among boys than girls, affecting between 6 and 16 percent of boys and between 2 and 9 percent of girls (Searight, Rottnek, & Abby, 2001). The disorder is marked by a persistent pattern of behaviors that violate the rights of others or that are socially inappropriate for the child’s age. Children with a conduct disorder are often selfish, relate poorly with others, and typically don’t display a normal sense of guilt. They are frequently the school bullies, given to threatening, fighting, abusing animals, and vandalism.
Attention Deficit Hyperactivity Disorder
The national survey summarized in Figure 9.2 includes attention deficit hyperactivity disorder (ADHD) as an impulse-control disorder. Some research indicates that as many as half of all children diagnosed with ADHD also meet the criteria for oppositional defi- ant disorder or conduct disorder (Connor, Steeber, & McBurnett, 2010). Adolescents who were diagnosed with ADHD as children are more likely to display oppositional defiant disorder as adults. They’re also more likely to fail or drop out of school and to abuse drugs and alcohol (Bussing, Mason, Bell, Porter, & Garvan, 2010).
ADHD is often marked by excessive activity for the child’s age, persistent inattention that is maladaptive, and high impulsivity. Not all children diagnosed with ADHD manifest all symptoms.
ADHD is the most frequently diagnosed childhood mental disorder. In fact, many think it is grossly overdiagnosed as a result of parents and teachers wanting explanations for child misbehaviors and pharmaceutical companies wanting to sell medication (Cohen, 2006). Another reason for overdiagnosis may be as simple as the fact that many young boys are still relatively immature when they start kindergarten. As a result, their behav- iors are marked by higher levels of activity and lower impulse control than is charac- teristic of older children. Following a study of some 12,000 kindergarten children, Elder (2010) reports that the youngest children were 60 percent more likely to be diagnosed as ADHD. By his estimates, as many as 1 million children in the United States may be wrongly diagnosed.
That some of the causes of ADHD are genetic seems clear. One line of evidence is the fact that only about 10 to 20 percent of cases are female. In addition, genomic researchers have now identified genetic markers closely related to ADHD (Ribases et al., 2011).
The most common treatment for ADHD involves stimulant drugs such as dextroamphet- amine (Dexedrine) and methylphenidate (Ritalin). Instead of acting as stimulants, these drugs have a paradoxical effect on children. That is, they appear to sedate rather than stimulate.
Other Impulse-Control Disorders
There are a number of other impulse-control disorders, most of which are relatively uncom- mon. They include:
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CHAPTER 9Section 9.4 Mood Disorders
• Kleptomania: an irresistible urge to steal things even when they’re not needed or particularly valuable
• Pyromania: a compulsion to set fires for personal pleasure and gratification
• Pathological gambling: an overwhelm- ing and persistent urge to gamble where gambling becomes a constant preoccu- pation and need that cannot easily be discontinued
• Trichotillomania: marked by the recur- rent pulling out of one’s hair, resulting in noticeable hair loss and considerable ten- sion if the individual tries to resist
9.4 Mood Disorders
The main feature of mood disorders is that they involve a significant disturbance in mood, typically expressed as depression or inappropriate euphoria (mania). Among serious mood disorders are major depressive disorder, bipolar disorder, and dysthymic disorder.
Major Depressive Disorder
Major depressive disorder is the most common of all mood disorders, affecting an esti- mated 6.7 percent of the adult U.S. population in a given year (National Institute of Men- tal Health, 2011). It is characterized by a conglomerate of symptoms, including apathy, listlessness, despair, loss of appetite, sleep disturbances, unwavering pessimism, and thoughts of suicide (although not all of these symptoms need be present in every case).
DSM-IV-TR criteria for major depressive disorder stipulate that there be at least one major depressive episode. A depressive episode is defined as a period of at least 2 weeks during which the individual suffers from a depressed mood and/or loss of interest and pleasure in normal life activities. The depressed mood typically characterizes most or all of every day.
There appears to be a clear relationship between suicide and depression. In fact, more than 90 percent of people who commit suicide suffer from depression or some other men- tal disorder (Suicide in the U.S., 2010).
Bipolar Disorder
Bipolar disorder, previously labeled manic depression, is approximately half as common as major depressive disorder, affecting an estimated 2.6 percent of the U.S. adult population (National Institute of Mental Health, 2011). It is marked by recurring episodes of mania or depression, although both are not always present. Occasionally the attacks are cyclical. That is, mania is followed by depression, which may then be followed by another period
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Impulse-control disorders include pyromania, kleptomania, trichotilloma- nia, and, as shown here, pathological gambling.
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CHAPTER 9Section 9.5 Substance-Related Disorders
of mania, and so on. More frequently, subjects experience a single episode of mania and one of depression, not necessarily in that order, and may then be free of both for long peri- ods—sometimes even decades. At other times, the condition is characterized principally by mania and is labeled bipolar disorder, Type I. Bipolar disorder Type II refers to a mood disorder where depression rather than mania dominates.
Mania contrasts sharply with periods of depression. It is characterized by periods of extreme and intense activity, irrepressible good humor, grandiose plans and involve- ments, and overwhelming displays of energy and joie-de-vivre.
Family and twin studies provide strong evidence of a genetic basis for bipolar disorder, where the heritability coefficient has been estimated at approximately 59 percent (Karege et al., 2010; Lichtenstein et al., 2009). In this context, heritability coefficient means the extent to which the variability in a characteristic is due to genetics.
Dysthymic Disorder
Whereas a major depressive episode lasts at least 2 weeks, dysthymic disorder (or dys- thymia) describes a chronically depressed mood that lasts at least 2 years and that is char- acteristic of most days during that period. Except for its longer duration, dysthymia is marked by much the same symptoms as a major depressive episode, but of lesser severity. In effect, it is a lower-grade, chronic, long-term depression.
9.5 Substance-Related Disorders
DSM-IV-TR describes two kinds of substance-related disorders: On the one hand are the substance use disorders, defined in terms of the abuse or dependence on drugs such as alcohol or narcotics; on the other are substance-induced disorders such as might be brought about by medication.
Substance Use Disorders
Substance use disorders include substance dependence and substance abuse. Dependence is defined mainly in terms of drug tolerance and withdrawal symptoms. That is, with increasing use many drugs have diminishing effects. This, as we saw in Chapter 2, is due primarily to the fact that most abused drugs are effective precisely because they increase the release of dopamine, the neurotransmitter associated with pleasure and reinforce- ment, or block its reuptake. One consequence is that the brain produces less dopamine naturally as it becomes increasingly dependent on external sources. Hence the apparent increased tolerance and the need to use more of the drug.
Withdrawal, the physiological and psychological effects of stopping drug use, results from a sudden reduction in stimulation of those areas of the brain associated with pleasure and typically leads to feelings of dysphoria—the opposite of euphoria. Withdrawal symptoms vary depending on the drug, its manner of ingestion, and the individual. Withdrawal is
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CHAPTER 9Section 9.5 Substance-Related Disorders
often marked by depression and anxiety, as well as by a strong craving, this being the hallmark of addiction. Sudden and complete withdrawal from alcohol dependence can be fatal.
Substance abuse refers to a maladaptive, recurrent, and persistent pattern of drug use without the tol- erance and withdrawal symptoms that mark drug dependence disorder.
Prevalence and Types of Drug Use As Figure 9.5 indicates, nearly half (46 percent)
of all Americans aged 12 and up have tried one or more drugs, although only 8 percent describe themselves as current users (those who have used the drug in the last 30 days). Nicotine and alcohol continue to be the most widely used drugs.
Drugs are typically classified in terms of their effects rather than their composition. There are narcotics such as morphine and opium, addictive drugs that produce sensations of well-being; sedatives, such as tranquilizers and barbiturates; stimulants, such as the amphetamines and cocaine; and hallucinogens, such as LSD, ecstasy, and Rohypnol. Mar- ijuana is also ordinarily classified as a hallucinogenic drug, although its effects are seldom as dramatic as those of LSD or mescaline (see Table 9.4).
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Successful treatment of substance use disorders is difficult and often uncertain.
Figure 9.5
Drug use in the United States based on interviews of around 68,000 participants aged 12 or more. Current users are defined as those who used the drug at least once during the past 30 days. Based on U.S. Census Bureau (2010b). The 2010 Statistical Abstract: The National Data Book: Table 202. Washington, DC: U.S. Government Printing Office.
ever used
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CHAPTER 9Section 9.5 Substance-Related Disorders
Table 9.4 Symptoms of Drug Use and Their Effects on the Nervous System
Drug Early Symptoms Long-Term Symptoms
Effects on Nervous System
Narcotics (opium, morphine, heroin, codeine, methadone)
Medicinal breath Traces of white powder
around nostrils (heroin is sometimes inhaled)
Red or raw nostrils Needle marks or scars on
arms Long sleeves (or other cloth-
ing) at inappropriate times Physical evidence may
include cough syrup bottles, syringes, cotton swabs, and spoon or cap for heating heroin
Loss of appetite Constipation
Bind to painkilling sites to dull sensation of pain; block reuptake of neu- rotransmitters such as dopamine.
Mimic endorphins (cause sensations of pleasure and well-being). With chronic use, the brain may stop producing endorphins so user develops tolerance and craves more drugs to feel good.
Sedatives (barbiturates, tran- quilizers, alcohol, Rohypnol, and GHB [the “date-rape” drug])
Symptoms of alcohol con- sumption with or without odor:
Poor coordination and speech
Drowsiness Loss of interest in activity
Withdrawal symptoms when discontinued
Possible convulsions
Activate GABA receptors (which are inhibitory and cause drowsiness).
GHB increases dopamine lev- els in the brain (associated with sense of well-being).
Stimulants (cocaine, crack, amphetamines, caf- feine, nicotine)
Excessive activity Irascibility Argumentativeness Nervousness Pupil dilation Dry mouth and nose with
bad breath Chapped, dry lips Scratching or rubbing of nose Long periods without sleep Loss of appetite
Loss of appetite Possible hallucina-
tions and psy- chotic reactions
Caffeine and amphetamines promote release of nor- adrenaline (causes excite- ment and wakefulness).
Cocaine and crack promote release of dopamine and inhibit its reuptake (causes sense of euphoria); leads to tolerance and addiction.
Hallucinogens (marijuana, LSD, PCP, mescaline, psilocybin)
Odor on breath and clothing Animated behavior or its
opposite Bizarre behavior Panic Disorientation
None definite for marijuana
Possible contribu- tion to psychoses and possible recurrence of experiences later
Stimulate serotonin activity. Interfere with noradrena-
line activity (produces hallucinations).
Inhalants (glue, paint thinner, aerosol sprays, solvents, other combustibles)
Odor of glue, solvent, or related substance
Redness and watering of eyes
Appearance of alcoholic intoxication
Physical evidence of plastic bags, rags, aerosol glue or solvent containers
Disorientation Brain damage
Long-term use can break down myelin, leading to muscle spasms, trem- ors, and other physical problems.
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CHAPTER 9Section 9.6 Other Axis I Disorders
9.6 Other Axis I Disorders
The four groupings of mental disorders we’ve considered so far—anxiety, impulse-control, mood, and substance-related disorders—are the four most commonly diagnosed in the United States. DSM-IV-TR lists a large number of additional categories, a few of which are summarized here.
Dissociative Disorders
Four principal dissociative disorders are described in DSM-IV-TR. They are called dis- sociative because they involve the splitting or separating of aspects of personality and functioning. Dissociative symptoms are sometimes seen in patients with posttraumatic stress disorder.
Dissociative Amnesia Dissociative amnesia is defined by a sudden and temporary loss of memory not attribut- able to any organic cause. Typically the memory loss is for some unusually stressful or traumatic event. Some instances of dissociative amnesia involve loss of memory of violent outbursts or suicide attempts.
Dissociative amnesia may take different forms, distinguishable in terms of the type of material that cannot be remembered and the time period covered by the amnesia. In local- ized amnesia, the individual is unable to recall anything for a period of time following some event, such as a car accident. In systematized amnesia, some events may be recalled during the circumscribed period, but many others will have been completely forgotten.
Generalized amnesia, highly unusual in practice although common as a literary and motion picture subject, involves the sudden inability to recall any detail of one’s previous life. Interestingly, ability to speak, intellectual skills, and motor skills are retained.
Continuous amnesia, also very rare, involves loss of memory from a specific time onward (up to and including the present). Continuous amnesia differs from generalized amnesia in that the individual retains memory of events prior to the onset of amnesia but cannot remember events that have just occurred.
Dissociative Fugue Like dissociative amnesia, dissociative fugue involves a loss of memory. In addition, it involves wandering and sometimes assuming a new identity. People suffering from a fugue state undergo an episode during which they have forgotten who they are but are unaware of having been anyone else. During this time, they may leave their homes and even establish very different lives somewhere else. Both onset and recovery are usually rapid, but the individual may then be left with a feeling of disorientation and confusion.
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CHAPTER 9Section 9.6 Other Axis I Disorders
Dissociative Identity Disorder The dissociative aspects of amnesia and fugue states are obvious: In both cases, it is as though parts of the individual’s personality and memory become separated from one another, some parts remaining temporarily inaccessible to the indi- vidual. Dissociative identity disorder, previ- ously called multiple-personality disorder, involves a more complex type of dissociation in which individuals are from time to time dominated by distinctly different, complex, highly integrated personalities. Typically, domination by one per- sonality is complete and does not involve any memory of other personalities, although it some- times does. Shifts from one personality to another may be sudden and dramatic.
The Three Faces of Eve (Thigpen & Cleckley, 1954) presents a classic illustration of dissociative iden- tity disorder. “Eve White,” who had been in psy- chotherapy for a period of time following complaints of severe headaches and blackouts, was a quiet, demure, soft-spoken woman. The therapist had no reason to suspect a mul- tiple personality, until one day:
As if seized by sudden pain, she put both hands to her head. After a tense moment of silence, both hands dropped. There was a quick, reckless smile, and, in a bright voice that sparkled, she said, “Hi, there, Doc!” The demure and constrained pos- ture of Eve White had melted into buoyant repose. (p. 137)
The “new” woman had no doubt that she was “Eve Black.” Later, “Jane” emerged as a third personality.
The repeated shifts of personality that occur in a dissociative identity disorder do not occur in the fugue state. In addition, the two or more personalities that alternately domi- nate the individual diagnosed as having a dissociative identity disorder are complete per- sonalities with well-integrated identities.
There is sometimes confusion between schizophrenia and “dissociative” or “multiple” identities, but the two are quite different. None of the schizophrenias involve dual (or triple) personalities in the sense of well-integrated, apparently normal, but separate mani- festations of identity. In addition, the schizophrenias typically involve serious problems of perceptual or cognitive distortion.
Among well-known people who have spoken about their experiences with dissociative identity disorder are actress and comedian Roseanne Barr and retired football player Her- shel Walker.
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Multiple personality, a popular fiction theme, is a rare condition now labeled dissociative identity disorder. In a few classic cases, it manifests itself almost as clearly as this doctored photo indicates.
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CHAPTER 9Section 9.6 Other Axis I Disorders
Depersonalization Disorder This is a disorder characterized by feelings of unreality. Those with depersonalization disorder often feel that they are in a dreamlike state, and perhaps that their body does not belong to them. Adam Duritz, frontman for the rock group Counting Crows, says of his depersonalization disorder, “[It] makes the world seem like it’s not real, as if things aren’t taking place. It’s hard to explain, but you feel untethered” (Celebrities with Dissociative Disorder, 2010). The disorder is uncommon and often disappears on its own.
Psychotic Disorders
This grouping includes a variety of disorders characterized by psychotic symptoms such as hallucinations (perceptions of experiences without corresponding external stimuli together with a compelling feeling that these are real) and delusions (false beliefs or opin- ions). These disorders are severe, debilitating conditions.
Schizophrenia Among the most severe and the most common of the psychotic disorders, schizophre- nia is characterized by emotional, cognitive, and perceptual confusion and a consequent breakdown of effective contact with others and with reality. Schizophrenia includes a number of distinct disorders, each distinguishable by its specific symptoms.
Catatonic type schizophrenia is so named because of the rigid, immobile (catatonic) pos- tures frequently adopted by patients, sometimes for hours. Typically, immobility is abso- lute during a catatonic stupor. Patients sometimes have no bowel or bladder control and have to be fed intravenously. The rigidity may be so complete that saliva runs unchecked down their chins because patients don’t even swallow.
Catatonic patients often alternate between periods of immobility and periods of intense physical activity accompanied by a great deal of excitement. Changes from one to the other are sometimes violent and dramatic. Periods of intense activity may be accompa- nied by overtly aggressive and dangerous behavior. If precautions are not taken, cata- tonic patients sometimes hurt themselves as a result of prolonged immobilization and hampered blood circulation as well as muscular strain, or as a result of doing themselves violence and injury while in a frenzy of catatonic excitement.
Paranoid type schizophrenia is probably the most common of the schizophrenias. Its symp- toms are not always as obvious as those of catatonia and may remain undetected for a time. Chief among these are delusions of grandeur and feelings of persecution, which go hand in hand. Paranoid type schizophrenics typically suffer from delusions that they are someone of extreme importance, believing, for example, that they are some historical fig- ure such as Napoleon or Jesus Christ. At the same time, they are overwhelmed by the con- viction that someone or something is after them—that they are being persecuted because they are important, because they know something that someone else wants, or simply because the historical figure they know themselves to be was persecuted. Such individu- als may spend a lifetime running from these imaginary persecutors, gathering evidence
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CHAPTER 9Section 9.6 Other Axis I Disorders
that they are being persecuted, sometimes hearing voices belonging to their enemies and hallucinating their presence. In severe cases, subjects may seek retaliation or defense and can become extremely dangerous. Sirhan B. Sirhan, assassin of Robert F. Kennedy, was diagnosed by defense experts as a paranoid schizophrenic who believed himself to be the savior of his people.
This classification of schizophrenias is not nearly so clear in practice as it might appear in theory. Numerous apparently schizophrenic patients cannot easily be classified within a single division, since symptoms often overlap or change over time.
Causes Various psychotic disorders appear to be related to malfunctions in the metabolic pro- cesses involved in the essential transformations that occur among synaptic neurotrans- mitters such as dopamine, serotonin, and epinephrine (Chapter 2). The effectiveness of many psychotherapeutic drugs appears to result from their effects on neurotransmitters, providing added evidence that these are implicated in some mental disorders. In addition, research with animals has shown that stressful environmental events may adversely affect essential metabolic processes in the brain.
Genomic research provides very strong evidence that schizophrenia in particular has a genetic component. Lichtenstein et al. (2009) summarized a large number of studies that looked at incidence of schizophrenia among twins, full and half siblings, and parents and estimated that the contribution of genetics to the disorder was approximately 64 percent. This finding is consistent with the belief that neurotransmitters are implicated in these mental disorders (Gray, Dean, Kronsbein, Robinson, & Scarr, 2010).
Sexual and Gender Identity Disorders
DSM-IV-TR recognizes three major subgroups of sexual disorders: those having to do with gender identity problems; those relating to unusual objects of sexual gratification and unusual modes of sexual expression (the paraphilias); and those relating to sexual dysfunction (psychosexual dysfunctions).
Gender Identity Disorders These disorders are defined in terms of a conflict between anatomical sex (male or female, genetically) and gender identity. Gender identity refers to the subjective feelings individu- als have concerning their sexuality. In the absence of gender identity problems, anatomi- cal males and females feel that they are male or female. A gender identity disorder would be evident in a strong feeling of discomfort with one’s anatomical sex and persistent feel- ings that one is or should be the other sex.
Gender identity disorders are sometimes confused with transvestism, which is a different disorder. Transvestism refers to the act of cross-dressing (dressing in clothing that is cultur- ally recognized as appropriate for the other sex) for sexual gratification.
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CHAPTER 9Section 9.6 Other Axis I Disorders
Gender identity disorders sometimes lead individuals to undergo sex-change procedures, which typically include both surgery and hormone treatment—as did Chastity Bono, daughter (now son, Chaz) of Sonny Bono and Cher (Chaz Bono Granted Name, Gender Change, 2010).
Paraphilias Paraphilias are a variety of sexual deviations (para: deviation; philia: attraction or love). Among these are the fetishes, involving sexual attraction to nonliving objects such as women’s undergarments, shoes, hats, and walnuts. Fetishism occurs primarily in males. Paraphilias eventually replace the person’s desire for intimacy with another person.
Zoophilia denotes sexual attraction to animals and the exclusive or preferred use of ani- mals for sexual arousal or release. It is apparently not as rare as once thought (Earls & Lalumiere, 2009).
Pedophilia describes a condition in which prepubertal children are employed as sexual part- ners or objects. Pedophilia is predominantly heterosexual rather than homosexual. It is the most commonly seen paraphilia in clinical practice (Fedoroff & Marshall, 2010). In particular, the use of children in pornographic books, films, and websites has increased dramatically.
Among the paraphilias are a number of other behaviors undertaken for sexual gratifica- tion. These include exhibitionism (flashing of private parts); fetishism (sexual arousal related to a physical object or situation); frotteurism (rubbing against a nonconsenting person); masochism and sadism (giving or receiving pain, respectively); transvestic fetishism (cross- dressing); and voyeurism (spying on people engaged in intimate behaviors).
There are no reliable statistics available on the prevalence of paraphilias, but they occur much more frequently in men than in women. One study found that 13.4 percent of adult male psychiatric inpatients admitted having one or more paraphilias—most commonly voyeurism and exhibitionism (Marsh et al., 2010).
Sexual Dysfunctions The sexual dysfunctions include impediments to the enjoyment of normal sexual activ- ity. Their principal psychological consequence is one of distress that may vary in severity depending on the individual concerned. Among sexual dysfunctions are inhibited sex- ual desire, inhibited sexual excitement (frigidity or impotence), inhibited female orgasm, inhibited male orgasm, premature ejaculation, dyspareunio (pain during coitus), and vag- inismus (spasms of the vagina making coitus painful).
Somatoform Disorders
Another grouping of disorders included in DSM-IV-TR is the somatoform disorders. These include a variety of conditions in which the patient has symptoms suggestive of some medical problem but no such problem can be found. People with somatoform disorder are often very anxious about their health. But the condition is not a result of
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CHAPTER 9Section 9.7 Axis II Personality Disorders
consciously fabricating or exaggerating symptoms (called malingering) or what are called factitious disorders (where the patient deliberately produces or feigns symptoms). Those with somatoform disorders genuinely believe they are physically ill.
9.7 Axis II Personality Disorders
All the preceding disorders are coded on Axis I of the DSM-IV-TR. Axis II includes mental retardation and personality disorders (sometimes called character disorders). Personality disorders are evident in behaviors that are socially inappropriate, inflexible, and often antisocial. Most of these behaviors typically become apparent during childhood or adolescence and are manifested as relatively stable, although sometimes highly mal- adaptive, personality characteristics.
Unlike those with more serious mental disorders, persons suffering from personality dis- orders usually continue to function in society. Often, too, they experience little anxiety over their behaviors since they are ordinarily unaware of their maladaptive nature. Most are unlikely to seek help on their own. Many individuals diagnosed with other forms of mental disorder have a long-standing history of personality disorders.
The personality disorders identified in DSM-IV-TR are the following:
• Paranoid personality disorder is marked by a profound, long-term, and unjustified conviction that other people are hostile, dangerous, and out to get them. It often leads to social isolation.
• Schizoid personality disorder is characterized by a disinterest in social relationships and a limited range of emotional reaction. It is sometimes evident in emotional coldness and a solitary lifestyle.
• Histrionic personality disorder, primarily a female disorder, is evident in excessive emotionality, attention seeking, and inappropriate flirtatiousness. People with his- trionic personalities typically want to be the center of attention and are often ego- centric and self-indulgent.
• Narcissistic personality disorder, primarily a male disorder, is evident in excessive self- love. Narcissus of the Greek legend loved himself above all else. Extreme arrogance, cavalier disregard for social convention and the rights of others, supreme confidence, and selfish exploitation of others are the principal characteristics of the narcissistic personality. Not surprisingly, such individuals appear only rarely in clinics.
• Antisocial personality disorder displays a pattern of pervasive disregard for, and violation of, the rights of others. Common characteristics might include lack of remorse for actions that hurt others, lack of empathy, cruelty to animals, poor and abusive relationships, and frequent problems with the law.
• Borderline personality disorder is evident in fluctuating and unpredictable moods that are often extreme. Those with borderline personality disorder tend to alter- nate between idealizing and devaluing, and they often have unstable and chaotic interpersonal relationships.
• Schizotypal personality disorder is marked by a need for social isolation, by what are often very different convictions and beliefs, and sometimes by odd or eccentric
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CHAPTER 9Section 9.8 Therapies
dress and behavior. Because the disorder is very similar to some forms of schizo- phrenia, its inclusion as a personality disorder is controversial.
• Avoidant personality disorder is characterized by an extreme and pervasive pat- tern of social inhibition evident in feelings of inadequacy and avoidance of social interaction.
• Dependent personality disorder describes a chronic and long-term condition in which the individual manifests excessive dependence on others for physical and emo- tional needs.
• Obsessive-compulsive personality disorder (OCPD) is different from obsessive-compulsive disorder (OCD) described earlier. Whereas OCD is an anxiety disorder marked by recurring obsessions (thoughts that won’t go away) and compulsions (behaviors that must be carried out repeatedly), OCPD is a personality disorder. It is marked by a chronic and persistent maladaptive pattern of interacting with other people and with the environment. Among its manifestations are excessive preoccupation with orderliness, perfectionism, and details and a need to control all aspects of the environment.
There is a danger, when reading quick descriptions of disorders, to recognize clusters of symptoms among people we know and wonder whether they might have this or that disor- der. For example, we all know people who are neat and orderly; but the fact is that probably none of them would come close to satisfying the criteria for obsessive-compulsive personal- ity disorder. Nor are all people who are shy candidates for a diagnosis of avoidant personality disorder. Note that for all other personality disorders, diagnosis is made only on the basis of specific combinations of persistent, prolonged, and/or chronic beliefs and behaviors.
9.8 Therapies
Basically, there are three broad approaches to treating mental disorders. In many instances, these reflect the therapist’s basic model, as summarized in Table 9.1. Thus, if the therapist views the disorder as being the result of a system malfunction (medical/ biological model), drug therapy, electroconvulsive shock therapy, or, more rarely, surgery will be the therapies of choice. If the therapist thinks the disorder is learned or results from inappropriate cognitions (behavioral and cognitive model), learning-based therapies may be employed. And if the therapist views disorders as resulting from psychic conflicts (psychodynamic model), some form of psychoanalysis may be used.
However clear this might seem in theory, the fact is that this handful of models has yielded hundreds of different therapies. And most therapists use a variety of them in dealing with mental disorder. Only rarely are the nonmedical approaches used without also using some form of drug therapy (antidepressants, sedatives, antipsychotic drugs, and so on).
Medical Therapy
Science has provided practitioners with chemicals and surgical procedures that can some- times arrest a disease or rectify a condition before its more extreme results appear. Syphi- lis, for example, can, if unchecked, lead to neurological impairment and the manifestation of various mental disorders. Simple and highly effective treatment with penicillin or
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CHAPTER 9Section 9.8 Therapies
related drugs in its early stages prevents their appearance. Similarly, thyroid problems, insulin problems, and a variety of metabolic and glandu- lar problems can be controlled chemically.
Drug Therapy Mild tranquilizers (Valium, Librium, Xanax, Ati- van) reduce anxiety and are useful for phobias, panic disorders, posttraumatic stress disorder, and so on. As we saw in Chapter 2, they have a sedating effect on brain activity.
Drugs known as antidepressants (Celexa, Lexa- pro, Prozac) are widely used in the treatment of depression. Most are not effective for several weeks or even months after starting treatment. They work well for about a third of patients with major depression.
Major tranquilizers (Haldol, Navane, Thorazine), called antipsychotic drugs, are used extensively with schizophrenic patients. Lithium and other drugs are widely used for bipolar disorder. Disul- firam (antabuse) is sometimes used with alcohol addiction.
There is some controversy over the effectiveness of these chemical substances. Most can have seri- ous side effects; overdoses can sometimes be fatal. Their use frequently accompanies other forms of therapy, where they might be employed simply to control anxiety or depression sufficiently that the therapist can more effectively employ other treatments.
Psychosurgery Another medical therapy involves surgical intervention. Among the most highly publi- cized of the surgical treatments is that of excising (removing) or making lesions (cuts) in the frontal lobes of the brain (prefrontal lobotomy), a procedure that is sometimes suc- cessful in reducing anxiety and alleviating depression. Among its frequent side effects, however, are a general dulling of emotional reaction, occasional epileptic seizures, listless- ness, and sometimes stupor (Jones, 2009). The procedure is now seldom used and is, in fact, illegal in many states and countries (Mashour, Walker, & Martuza, 2005).
Insight Therapy
The major insight therapy is psychoanalysis, which is based on Freudian theory. Its identi- fying characteristic is the belief that alleviating mental disorders depends upon achieving insight into the causes of present behavior.
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Treatment of mental disorders has changed dramatically with drug therapy. Calming medications can now accom- plish what required a straightjacket only a few decades ago.
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CHAPTER 9Section 9.8 Therapies
Freud believed that mental disturbances result from conflict between basic impulses (id) and conscience (superego) that gives rise to anxiety. The ego’s role is to find ways of reducing this anx- iety. The psychoanalyst’s main task is to uncover basic sources of conflict, many of which will have a sexual basis.
One of the techniques used in psychoanalysis is free association, where the patient is encouraged to say whatever comes to mind without evaluat- ing or discarding material. The hope is that these associated ideas will eventually lead therapist and patient back to a fundamental source of conflict or, failing that, that the therapist will recognize where blocks to association occur. These mental blocks are assumed to be the ego’s defenses against revealing sensitive issues. Through repeated ver- bal probing, the analyst may eventually be able to understand these blocks and perhaps even remove them.
The analysis of dreams is another technique employed in psychoanalysis. Freud believed that ego defenses are at their weakest during sleep, and that sources of intense psychodynamic con- flict are therefore often revealed during dreams. He distinguished between the apparent (mani- fest) meaning of dreams (a baseball bat is a base- ball bat, whether in a dream or in a batter’s hand)
and their symbolic meaning (for all you and I know, a baseball bat might be a symbol of penis envy in a dream).
In the course of repeated psychoanalytic sessions, the therapist pays particular attention to the relationship that develops between analyst and patient. According to Freud, this relationship often illustrates transference: the therapist becomes somebody of importance in the patient’s life, perhaps embodying a source of historical conflict. Thus, patients react to their therapists as they would to a parent or a lover, displaying in their behavior many of the attitudes they might have had toward that important person, perhaps at a time when conflict was being born. In effect, attitudes and feelings that might be the basis of conflict are transferred to the analyst. Recognizing this, the analyst may then interpret this transference, along with information derived from analysis of dreams and of association, thereby arriving at some insight into the source of the patient’s conflict.
Learning-Based and Cognitive Therapy
Therapies based on learning theories stand in sharp contrast to psychoanalysis. The learn- ing therapist is concerned mainly with the manifestations of disorders rather than with
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Sometimes a cigar is just a cigar, said Freud. Still, he insisted that the sym- bols in our dreams can provide impor- tant clues to our disturbances. But the truth is, symbols in dreams don’t have universal meanings. Perhaps, like Freud’s cigar, the rope in this nightmare is just a rope. Then again, maybe not.
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CHAPTER 9Section 9.8 Therapies
their causes, and assumes that these manifestations can be unlearned or that more accept- able forms of behavior can be learned in their stead. Accordingly, these therapies make extensive use of learning principles.
Behavior Modification Although there are a variety of approaches to behavior modification, most are based on the general principle that people are influenced by the consequences of their behavior— that their immediate environmental circumstances are more relevant than early experi- ences or psychic conflicts.
In a procedure called systematic desensitization (or counterconditioning), the therapist tries to replace an undesirable response with another incompatible and more desirable response. The procedure is particularly effective for phobias (Head & Gross, 2009). When treating a severe bird phobia, for example, the therapist begins by training the patient in relaxation. Once she has learned to relax, she is presented with the least frightening item on an ordered list of fear-inducing situations that she has previously described—perhaps just an outdoor scene with no birds and no bird noises. She is asked to imagine this scene while relaxing, relaxation being incompatible with anxiety and fear. In successive ses- sions, the patient is encouraged to imagine other situations until she can imagine a bird without any anxiety. Eventually, she might be able to hold one in her hand.
Closely related to systematic desensitization is exposure therapy, where the patient is simply exposed to fear- or anxiety-producing stimuli. The procedure is much faster than systematic desensitization because it is not based on the notion that the patient should feel no fear. Rather, it is based on the belief that simply exposing the patient repeatedly to the fear-related stimulus will lead to reduction and eventual elimination of fear reactions. Research indicates that exposure therapy, sometimes using computer-based virtual reality simulations, can be highly effective in treating anxiety disorders such as posttraumatic stress disorder (Reger et al., 2011).
A related learning-based approach, aversive conditioning, attempts to attach negative feelings and to bring about avoidance behavior with respect to certain situations. For example, patients might be subjected to a mild electric shock or other aversive stimulus when they engage in, or think about, some inappropriate behavior. Some sexual disorders such as fetishes can be effectively treated with this approach.
Positive Reinforcement Another learning-based approach uses positive reinforcement for desirable behavior, some- times combined with the withdrawal of reinforcement for undesirable behavior. For example, highly withdrawn patients might be given tokens, which can be exchanged for meaningful rewards, for social interaction. Instead of tokens, verbal reinforcement (praise) might be used.
Rational Emotive Behavior Therapy Ellis’s (1974; Ellis & MacLaren, 2005) rational emotive behavior therapy (REBT) is a cognitive therapy. It is premised on the assumption that our cognitive interpretations of
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CHAPTER 9Section 9.8 Therapies
events and situations are the root of emotional turmoil. Accordingly, therapy shouldn’t focus on obscure historical causes but on the individual’s immediate interpretation of the meanings of environmental events.
Ellis lists a number of erroneous assumptions that people make. When these assumptions are violated, the individual is anxious and unhappy. The goal of the therapist is to direct the patient’s attention to these irrational ideas and to change them. The whole point is to replace irrational beliefs with more rational ones through cognitive and verbal means. Ellis lists many irrational beliefs, but he describes the following three as the main ones (Ellis, 2003):
1. I must always perform outstandingly well and win everybody’s complete approval or I am bad, incompetent, and unworthy.
2. Other people must always treat me well and fairly; otherwise they are rotten and bad and don’t deserve a good life.
3. My life must always be favorable, safe, hassle free, and enjoyable; if it isn’t, I won’t be able to bear it and it won’t be worth living.
Ellis describes these irrational ideas as beliefs (B) in his A-B-C theory of disturbance. According to this theory, an emotional reaction or consequence (C) is usually ascribed to some specific experience (A, for activating event). In fact, however, the emotional con- sequence (C) is not a function of the event (A), but of the beliefs (B) the individual has. Since the majority of these beliefs are irrational (if they were rational, the emotional con- sequences would not ordinarily be disturbing), the goal of therapy is to replace irrational with rational beliefs (Figure 9.6).
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(cause attributed by patient)Rejection by women
C (emotional)
A (activating event)
B (belief)
If I am rejected, I am worthless
Fear of social/sexual interaction with women
Figure 9.6
Ellis’s A-B-C theory of disturbance. An event (A) leads to an emotional consequence (C) only because of the individual’s beliefs (B). If you reject me and I am upset, my upset is due not to your rejection, but to my irrational belief that I should never be rejected.
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CHAPTER 9Main Points
The Effectiveness of Therapies
A large number of outcome studies have been conducted to look at the effectiveness of dif- ferent therapies. Some look at improvements in morale—in the individual’s sense of well- being and happiness. Others look at symptom reduction or at the reduction of impairment and at improvements in level of functioning. Many use highly objective measures, such as time spent doing compulsive behaviors, duration of abstinence from alcohol or drugs, incidence of gambling, or number of panic attacks.
Outcome studies indicate clearly that therapies are often remarkably effective for pretty well all mental disorders, including substance abuse (Sledge & Hutchinson, 2010), bor- derline personality disorder (Waldinger, 2010), depression (Richards & Perri, 2010), and many other disorders.
Some therapies are clearly more effective than others for specific purposes. For example, exposure therapy has been shown to be highly effective in treating or preventing posttrau- matic stress disorder (Reger et al., 2011). Similarly, there is evidence that rational emotive behavior therapy is effective for depression—as are drug treatments (Sava, Yates, Lupu, Szentagotai, & David, 2009). And drug therapies are effective for an enormous number of mental disorders, including bipolar disorders, anxiety disorders, personality disorders, and psychotic disorders.
Main Points 1. Historical and Current Views of Mental Disorders: Many mental disorders are
highly culture specific, typically reflecting unexpected and rare behaviors in that culture. Causes may be organic/medical or learned. They are marked by persis- tent patterns of thought or behavior that are distressful and/or lead to significant impairment in ability to cope.
2. Anxiety Disorders: Disorders characterized mainly by anxiety include panic attacks (sudden onset of terror); generalized anxiety disorder (pervasive free-floating anxiety); phobic disorders (a range of fears, including social phobia and agoraphobia as well as fear of specific objects or situations); obsessive-compulsive disorder (recur- ring irrational thoughts and impulses); and posttraumatic stress disorder (resulting from a traumatic event).
3. Impulse-Control Disorders Usually First Diagnosed in Children: Disorders in which the individual fails to resist an impulse to act in a harmful or inappropri- ate way include aggression-based impulse-control disorders (impulses are related to aggressive and violent acts toward people or property, sometimes evident in hostile, defiant, or criminal behaviors); conduct disorders (persistent and often aggressive violation of other people’s rights and property); ADHD (marked by excessive activity for the child’s age, inattention, and impulsivity); and other impulse-related disorders, such as pyromania, kleptomania, and compulsive gambling.
4. Mood Disorders: These disorders of affect include major depressive disorder (a common and serious disorder involving despair and unwavering pessimism);
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CHAPTER 9Main Points
bipolar disorder (formerly manic-depression); and dysthymic disorder (a longer-term but less severe depression than major depressive disorder).
5. Substance-Related Disorders: These include substance use disorders (substance dependence, marked by tolerance and withdrawal symptoms, and substance abuse, where the criteria for dependence have not been met).
6. Other Axis I Disorders: Among the many other disorders included in DSM-IV- TR are dissociative disorders (where aspects of personality and functioning sepa- rate, as in dissociative amnesia, fugue, or identity disorder); psychotic disorders (severe, debilitating disorders, including the various forms of schizophrenia); sexual and gender identity disorders (problems associated with discomfort with one’s anatomi- cal sex; the paraphilias, where objects of sexual interest are bizarre and socially unacceptable; and sexual dysfunctions such as impotence or frigidity); and somato- form disorders (marked by physical complaints that cannot be explained by injury or disease).
7. Axis II Personality Disorders: These are evident in persistent behaviors and thoughts that are socially inappropriate and maladaptive. They include the fol- lowing personality disorders: paranoid (view of others as hostile, dangerous); schizoid (disinterest in social relationships); histrionic (excessive emotionality); narcissistic (self-love); antisocial (violation of rights of others); borderline (extreme, unpredictable, fluctuating moods); schizotypal (social isolation and odd or eccen- tric behavior); avoidant (social inhibition); dependent (excessive reliance on others for all needs); and obsessive-compulsive (maladaptive interactions centering on order, perfectionism, and control).
8. Therapies: The many dozens of different approaches to therapy can be sorted into medical approaches (drug therapy, psychosurgery, electroconvulsive therapy); insight therapy (Freudian psychoanalysis, in which dreams and free association might be used to uncover mental blocks and defenses to provide insight and eventual resolution); and learning-based and cognitive therapies (in which condi- tioning models and reinforcement programs might be used alone or in combina- tion with more cognitive approaches such as Ellis’s REBT).
9. The Effectiveness of Therapies: The results of outcome studies generally sup- port the conclusion that different therapies can be highly effective for most men- tal disorders.
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CHAPTER 9Main Points
agoraphobia
amok
anorexia nervosa
Asperger’s syndrome
attention deficit hyperactivity disorder (ADHD)
autism
aversive conditioning
behavior modification
bipolar disorder
brain fag
conduct disorder
delusions
depersonlization disorder
dissociative disorders
dissociative fugue
dissociative identity disorder
drug tolerance
dysphoria
dysthymic disorder
ethnic psychosis
exposure therapy
free association
generalized anxiety disorder
hallucinations
hallucinogens
heritability coefficient
impulse-control disorders
insanity
intellectual disabilities
intermittent explosive disorder
major depressive disorders
major depressive episode
mental blocks
mental disorder
models
mood disorders
narcotics
neuroses
obsessive-compulsive disorders
oppositional defiant disorder
panic attacks
panic disorder
paradoxical effect
paraphilias
personality disorders
phobias
pibloktog
posttraumatic stress disorder (PTSD)
prefrontal lobotomy
rational emotive behavior therapy (REBT)
schizophrenia
sedatives
social phobia
somatoform disorders
specific learning disabilities
specific phobias
stimulants
substance-related disorders
susto
systematic desensitization
transference
Windigo
withdrawal symptoms
Study Terms
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10
Social Psychology
Focus Questions
By the end of the chapter, you should be able to answer the following questions: • With what is social psychology concerned? • How are compliance and conformity different? • How do attitudes, beliefs, opinions, and stereotypes differ? • What are some key forces that might serve to change attitudes? • How is aggression defined and explained? • What are some causes and manifestations of antisocial and prosocial behavior? • What is love?
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CHAPTER 10Social Psychology
I don’t know if life is greater than death, but love was more
than either. —Tristan’s dying words, Tristan +
Isolde (2006 movie)
Chapter Outline
10.1 Social Psychology What Is Social Psychology?
10.2 Attitudes and Attitude Change Compliance and Conformity Social Pressure and Compliance Obedience Persuasion Cognitive Dissonance Attribution and Attitude Change
10.3 Antisocial Behaviors Aggression and Violence Bystander Apathy
10.4 Prosocial Behaviors Altruism
10.5 Interpersonal Relationships The Rules of Attraction Liking and Loving A Model of Love A Last Word to the Poets
One of the greatest love stories of all time is the ancient legend of Tristan and Isolde. As the story goes, King Mark of Cornwall is to marry Isolde, daughter of the King of Ireland. So he sends his nephew, Tristan, to fetch her. On the journey back, Tristan and Isolde fall madly in love and begin an affair that lasts even after, duty bound, she has married King Mark. When the king discovers the betrayal, he banishes Tristan from the kingdom but forgives Isolde. Later, Tristan marries Iseult because her name reminds him of Isolde—but he never consummates the marriage. When he falls gravely ill, he sends a ship for Isolde thinking he will surely die without her. If she agrees to come, the ship is to return with white sails unfurled; and if she doesn’t, the ship will run black sails.
As soon as she receives the message, Isolde leaves King Mark and sets sail for Tristan, white sails flying. But when Iseult sees that the returning ship carries white sails, she runs to Tristan and says, “The sails are black.” Tristan dies of grief. Very soon after that, Isolde dies of a broken heart.
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CHAPTER 10Section 10.1 Social Psychology
10.1 Social Psychology
The story of Tristan and Isolde illustrates two of the most important concerns of social psychology: human relationships—powerfully illustrated in their tragic tale of doomed love—and how others influence our behaviors—evident in how Isolde bent to the duty imposed by her social circumstances.
What Is Social Psychology?
Social psychology is concerned with relationships among individuals or between indi- viduals and groups. In Allport’s (1968) terms, “social psychologists regard their discipline as an attempt to understand how the thought, feeling, and behavior of individuals are influ- enced by the actual, imagined, or implied presence of others” (p. 3). Thus, social psychology says something about why Isolde married King Mark (the powerful influence of social customs and values)—and why she later returned to Tristan (the strength of their love).
The subject matter of social psychology spans almost all facets of human behavior save those that are clearly individual and not affected by the presence of others. Most of what we learn, think, feel, and do is influenced by others. There are very few people whose lives are totally devoid of human relationships. To be completely isolated socially would require absolute geographic isolation or some form of mental disorder. Social isolation, interesting though it may be, provides no pieces of the puzzle for the social psychologist. Social psychology tries to understand the socially influenced aspects of attitudes, relation- ships, and behaviors.
10.2 Attitudes and Attitude Change
Understanding social influence is basic to understanding the formation and changing of attitudes, opinions, stereotypes, and prejudices. An attitude is a prevailing and consistent tendency to react in a given way based on indi- vidual beliefs. Attitudes have important emotional connotations as well as behavioral and cognitive components. They may be described as positive or negative; neutral reactions don’t qualify as attitudes. Attitudes have strong motivational consequences, a fact that distinguishes them from opinions. Although opinions are also evaluations, they don’t drive people to action as do attitudes (Figure 10.1).
Stereotypes are widely held attitudes and opinions concerning identifiable groups. They usually include value-laden beliefs and are often based on emotional reaction, illogical reasoning, and faulty generalization.
Although stereotypes have often been assumed to be negative, they can also be posi- tive. Negative stereotypes have been shown to have detrimental effects on many kinds of interactions, including, for example, between teachers and students (Marx, 2009). In the same way, positive stereotypes can have a beneficial effect on learning and performance (Kwong See & Nicoladis, 2010).
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
As generalized beliefs about groups, stereotypes are virtually indispensable in daily inter- action. They’re like shortcuts that tell us how to react without having to wait to see how other people are going to behave. For example, we may have a stereotype that tells us that panhandlers become aggressive if we look them in the eye but throw nothing in their hats. So we don’t look them in the eye, or we go ahead and toss heavy coin into their hats.
Not surprisingly, there is considerable research, much of which is summarized by Lee, Jussim, and McCauley (1995), that many stereotypes, including those applied specifically to identifiable ethnic groups, agree remarkably well with more objective evaluations. This doesn’t mean that stereotypes are invariably accurate and useful; many are bigoted, inap- propriate, and shockingly unjust.
Unlike stereotypes, which are widely held beliefs about groups, prejudices are personal rather than shared prejudgments. To be prejudiced implies having arrived at an opinion prior to obtaining relevant facts.
How attitudes, opinions, stereotypes, and prejudice are different is evident in a sample of most people’s behaviors and beliefs. For example, Eddie’s strong feeling that involvement in war is immoral and his attempt to persuade others they should protest illustrate an atti- tude—a personal, emotional, and clearly motivating belief. If he is convinced that military
Abandon job. Try to negotiate double overtime
pay. Talk to union.
Anger
Belief component
Behavior component
Emotional component
Joy Sadness
It is absolutely not right to force people
to work overtime!
Overtime means more money!
I won’t be able to watch baseball on weekends.
Figure 10.1
The three components of attitudes, illustrating how attitudes motivate behavior.
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
personnel are highly immoral even though he has had little exposure to them, that conviction would be a prejudice—a preconceived judgment. His per- sonal belief that seatbelt legislation is unnecessary and uneconomical is an opinion—a personal belief not necessarily shared by others and not directed toward an identifiable group. And his assumption that Americans are sufficiently resourceful and industrious that they will easily cope with global warming and other crises illustrates a stereotype— a belief about a specific group that is shared by a significant number of people.
Compliance and Conformity
Attitudes are powerful motives for behavior. And although they tend to be stable and long lasting,
they can change in response to various factors, including new information we acquire, social pressure, tendencies we have to obey or disobey, and the effects of persuasion. As we change our attitudes, our behavior changes as well; it can be said to conform or comply with the forces that change it. Conformity is defined by long-term changes in behav- ior where attitudes have been affected, opinions modified, or stereotypes and prejudices altered. Short-term changes in behavior that don’t significantly alter any of these types of beliefs are said to lead to compliance rather than to conformity.
The distinction between conformity and compliance is more subtle in practice than in theory. If I hold a carrot a tantalizing distance in front of a mule, thereby inducing that clever animal to swim across a small body of water, I have simply succeeded in getting a mule to comply with my pointless wishes. Assuming that the mule still doesn’t like water and doesn’t develop the habit of taking off its shoes and wading for pleasure of a Sunday morning, it cannot be argued that I have developed a conforming mule simply by bully- ing one into complying. To become a conforming mule, the creature would have to change its attitudes toward water and deliberately wade with the other wading mules because of its attitudes rather than for a measly carrot. If you happened along and saw the mule swimming, however, you would not know whether it was complying or conforming.
To bring the illustration closer to home, you may be said to conform to social norms to the extent that you approve of them and therefore act accordingly. Complying with the same social norms might involve exactly the same behavior but would be based on motives other than your approval of the norms.
Social Pressure and Compliance
The classic studies of compliance, frequently described as studies of conformity, are those conducted by Asch (1955). In a typical experiment, “subjects” are placed in a semicircle fac- ing an easel on which the experimenter places two large cards. One of these cards has a sin- gle vertical line on it (the standard); the other has three vertical lines of different lengths, one
The urge to conform is a powerful social motive. It does much to ensure that societies function smoothly. But do we all have to check our watches at the same time?
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
of which is clearly equal in length to the standard (Figure 10.2). In a “test of perceptual accu- racy,” subjects are required to determine which of the three lines is equal to the standard.
In fact, the test is not of perceptual accuracy but of social pressure and its effects on com- pliance. Only one of the “subjects” is actually a subject; the others are confederates. The confederates have been instructed to answer correctly for the first few trials and then to answer incorrectly but to agree on the incorrect answer. The real subject, who has no rea- son to suspect that the others are not also subjects, is the second last to answer.
In a series of studies carried out in three different institutions, 123 subjects answered incor- rectly 36.8 percent of the time. A control group not exposed to social pressure answered correctly more than 99 percent of the time. Typically, subjects were confronted with the conflicting opinions of as many as eight confederates. However, varying the number of confederates revealed that a majority of three was equally effective in eliciting compliance with the group (Asch, 1955). This observation is strikingly similar to the ancient Chinese proverb, three men make a tiger (which is interpreted to mean that people will believe the most absurd things as long as enough other people seem to believe them) (Figure 10.3).
When subjects in the Asch experiment were questioned later, it turned out that they knew all along that their responses and those of the confederates were in error. But they still
Standard
Comparison
Figure 10.2
Asch (1955) used a simple visual perception test to determine the effects of social pressure. Participants, unwittingly part of a group of the experimenter’s confederates, who often agreed on the wrong answer, were asked which comparison line is the same length as the standard line.
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
complied—later explaining their behavior in a variety of ways, such as by attributing it to “misjudgment” or “poor eyesight.” Interestingly, however, not all were equally suscep- tible to the effects of group pressure. Fully one quarter of subjects continued to answer completely independently, never agreeing with the incorrect majority. In contrast, others nearly always agreed with the majority.
These experiments have often been interpreted as evidence of the gullibility of individu- als and their susceptibility to group pressure. The implication is that these are undesirable qualities. In fact, however, it is precisely because we are susceptible to group pressures that complex social institutions such as governments, schools, and churches work. It is also because we are sensitive to the opinions and attitudes of others that we are able to interact effectively with them.
This should not be taken to mean that compliance and conformity are always good; it does mean, however, that they are not always bad, in the same way as stereotypes aren’t always totally wrong and useless.
Obedience
Let’s say your superior orders you to do something nasty like hurt some innocent person: How likely are you to rear up on you hind legs and say, “Nope, I can’t do that”? Or will you just go ahead and do as you are told?
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Figure 10.3
When paired with a single confederate, subjects in the Asch (1955) study were about as accurate as if they had been alone. But when paired with four, they complied with the majority more than one third of the time. Adding more confederates did not increase compliance significantly. Data from page 34 of Asch, S. E. (1955). Opinions and social pressure. Scientific American, 193(5), 31–35.
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
The Milgram Studies Milgram (1963, 1965), in a remarkable series of controversial experiments, provides an answer. In these studies, subjects were duped into believing that they were confederates of an experimenter studying the effects of punishment on learning. An alleged subject (actually a confederate, termed a stooge in this experiment) was to be presented with a series of learning tasks while attached to electrodes so that he could be shocked whenever he made an error. The real subjects’ task was to depress the switch that would deliver the shock. Subjects were first connected to the electrodes and administered a mild shock so that they would have no reason to think that the shocks would not be real. They were then seated in front of an instrument panel containing a series of switches labeled from 15 to 450 volts, in 15-volt increments. Verbal descriptions above the switches ranged from “Slight shock” to “Danger: severe shock” at 390 volts and “XXX” at 435 volts.
In the first Milgram (1963) experiment, “victims” (stooges who did not actually receive any shocks) were placed in a separate room and were instructed to make a predetermined number of errors. The subjects, who controlled the switches, were instructed to administer a shock for every error the victim made, beginning with the first switch and progressing as high as necessary, in one-step increments. If a subject hesitated or indicated any unwill- ingness to continue, the experimenter would employ a predetermined verbal “prod”; that prod failing, a second would be employed, then a third, and finally a fourth. In all cases, the prods were given in sequence:
Prod 1. Please continue, or please go on.
Prod 2. The experiment requires that you continue.
Prod 3. It is absolutely essential that you continue.
Prod 4. You have no other choice. You must go on. (p. 374)
Amazingly, none of the subjects categorically refused to obey from the outset. In fact, of the 40 original subjects, 26 obeyed the experimenter’s instructions right to the very end (“victims” committed sufficient errors to ensure that subjects would have an opportunity to administer the most severe shock—450 volts). The remaining 14 all obeyed until at least the 300-volt level (Figure 10.4).
In related studies, Milgram (1965) looked at the effect of the distance between subject and victim using four different experimental conditions. In one, the subject could see, hear, and touch the victim, since both were in the same room. In a second, the subject could hear and see the stooge, but could not touch him. In a third condition, the subject could hear the stooge, but not see him, a curtain having been drawn between the two. In a final experimental condition, the subject could neither see nor hear the victim.
Again, subjects complied with the experimenter’s requests. But now, average intensity of shocks increased in direct proportion with the distance between the subject and the victim, with the highest shocks being administered when the subject could not see or hear the victim.
One finding that is sometimes overlooked when reporting the more sensational results of the Milgram obedience studies is that most subjects, whether or not they obeyed, were disturbed by the procedure. Milgram (1963) writes:
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
In a large number of cases the degree of tension reached extremes that are rarely seen in socio-psychological laboratory studies. Subjects were observed to sweat, tremble, stutter, bite their lips, groan, and dig their fingernails into their flesh. These were characteristic rather than exceptional responses to the experiment. . . . On one occasion we observed a seizure so violently convulsive that it was neces- sary to call a halt to the experiment. (p. 375)
Studies such as these are disturbing for a number of reasons. They reveal aggressive aspects of humanity that many would prefer not to admit; they underline the power of authority and compliance in contrast to individual choice and freedom; and they present some serious moral issues with respect to deceiving subjects into engaging in behaviors that potentially are psychologically damaging.
Given the fact that psychological investigations now typically require approval by an eth- ics committee and strict adherence to ethical guidelines, the Milgram studies have not often been replicated. However, Burger (2009) did replicate these studies with one sig- nificant variation: When subjects reached the level of 150 volts (the point at which the “stooge” has been instructed to moan and protest), the experiment was discontinued.
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Severity of shock indicated on switch, in 15-volt increments
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Figure 10.4
All subjects in the Milgram study “obeyed” and administered shocks beginning at 15 volts and going to at least 300 volts. The next switch was labeled “extreme intensity shock.” Five of 40 subjects refused to go any further; 26 went all the way to 450 volts. Based on tabular data in Milgram, 1963.
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
Strikingly, Burger found that obedience rates were only slightly lower 45 years after the original Milgram studies. And he found, as well, that obedience rates for men and women did not differ significantly. Although, as Twenge (2009) notes, there has apparently been an increase in personality traits that reflect nonconformity (higher assertiveness and self- esteem), there continues to be a strong urge to comply with authority and to conform to the majority.
The Prison Experiment Unquestioning compliance with authority has been dramatically demonstrated in concentration- camp atrocities performed under direct orders from powerful, potentially highly punitive or highly reinforcing superiors. More recently, it has been flagrantly evident in the wanton acts of abuse and torture of prisoners at Abu Ghraib in Iraq (Bartone, 2010). But there may be more to these atrocities than simple compliance with authority.
There is a culture among prisoners and guards, Zimbardo (2007) explains, that is the key to understanding how abuse and torture can occur under these circumstances. In a clas- sic experiment carried out at Stanford in 1971, 12 young men, who were among 75 who had answered an ad asking for volunteers for an experiment on prison life, were abruptly arrested by police, handcuffed, and brought into a prison (actually, converted basement space in a Stanford building). There they were stripped, searched, deloused, fingerprinted, and in every way treated like real prisoners. Their guards were 12 other student volun- teers instructed to do whatever was required to maintain order and command respect.
The results are sobering: Almost immediately, guards developed coercive, aggressive tac- tics, humiliating and dehumanizing prisoners. They forced them to do things like clean out toilet bowls with their bare hands, count aloud to reinforce their new numerical identities, and do protracted physical exercise as “punishment” when they made errors. The conse- quences were sufficiently severe that 5 of the 12 prisoners had to be “released” before the
experiment ended—and this in spite of the fact that the prisoners staged a “revolt” on the second day of the experiment. The experiment was slated to run for 14 days, but it was abruptly terminated on the 6th day when one of the more than 50 out- siders who had seen the prison was shocked at what she saw and raised objections about the eth- ics of the experiment (Zimbardo, 2007).
The effects of the Stanford prison experiment were far greater than anticipated. Both the pris- oners and the guards carried their roles to an unforeseen extreme. Fully a third of the guards exhibited what Zimbardo describes as genuinely sadistic tendencies. What the study illustrates, explains Zimbardo, is the power of institutions and of institutionalized roles—dramatically illus- trated once more in Abu Ghraib. In contrast, the Milgram experiments were more about the power of individual authority.
The Stanford prison experiment sug- gests that we quickly and easily adopt roles even when they run counter to our values. And the Milgram obedi- ence studies underscore our willing- ness to obey those in authority. What happened in Abu Ghraib, pictured here, may reflect both obedience and role conformity.
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
The entire Stanford prison study was photographed and filmed and is available online (Stanford Prison Experiment, 2011).
Persuasion
Social influence is a powerful and pervasive force. We know that people are influenced by norms expressed in the behaviors and attitudes of others and that they respond to authority and to the roles they’re called on to play. Research and common sense also suggest that there are many subtle forms of social influence to which we are responsive. Persuasion is a global term for some of these influences. It refers to deliberate, usually verbal, attempts to alter beliefs or behavior. Television commercials, religious and political propaganda, newspaper and magazine advertising, and political campaigning all represent attempts at persuasion.
The most powerful forms of persuasion are those that succeed in changing attitudes rather than simply behavior. Attitudes may change as a result of events within the person, a pro- cess that is typically slow, although it may result from rational decisions and occur very rapidly. Attitudes may also change as a result of external events that are accidental rather than deliberately persuasive. Thus, an individual who is rescued from death by a mem- ber of a minority group toward which he has held highly negative attitudes may quite suddenly develop positive attitudes toward the group. Finally, attitudes may change as a result of persuasion.
Three characteristics of persuasion are important in determining its effectiveness: the nature of the message, its source, and some of the characteristics of the person being persuaded.
Importance of Message Characteristics That the nature of the message is important is evident in the observation that it is much easier to persuade someone of something that fits in with previous beliefs or with the individual’s goals and wishes. By the same token, it is difficult to change attitudes when the message runs counter to strongly entrenched prejudices and stereotypes.
Importance of Message Source Belief in the importance of the source of persuasion is evident in the advertising media’s use of powerful models in their attempts to persuade. Research in social psychology sug- gests that the belief is warranted. Persuasion that comes from a source marked by quali- ties such as expertise, liking, and high trust is most effective (Feng & MacGeorge, 2010). Similarly, people are more easily persuaded by opinions that are apparently shared by many, rather than by few. Horcajo, Petty, and Brinol (2010) presented subjects with strong or weak persuasive arguments, ascribing these either to a “majority” or to a “minority.” Not surprisingly, whether they are strong or weak arguments, those attributed to a major- ity source are more persuasive than those thought to come from a minority.
Motives that might be attributed to the persuader also play an important role (Ranganath, Spellman, & Joy-Gaba, 2010). When persuaders are arguing in their own best interests,
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
the persuasion may not be nearly as effective as when the argument is opposed to the persuader’s self-interest. When petroleum-linked interests suggest that no, water and air contamination are not increasing as a result of oilfield activity, you are unlikely to believe them. The same argument presented by a radical “green” group is much more convincing.
Importance of Audience Characteristics Finally, certain characteristics of the person being persuaded, such as intelligence and indepen- dence, are also important. In one study, Cacioppo, Petty, Kao, and Rodriguez (1986) had participants read either a high-quality or a low-quality essay relating to why a university should institute com- prehensive examinations. The more intelligent
subjects were more convinced by the high-quality essay. In contrast, other subjects seemed less sensitive to the quality of the argument and were as easily convinced by the low- quality as by the high-quality essay.
Note that in spite of these studies, attitudes are, by definition, pervasive predispositions to respond in given ways; as such, they resist change. So, although it may be relatively sim- ple for a skilled social psychologist to persuade individuals to vote for her, she may expe- rience considerably more difficulty in getting them to love members of minority groups against whom they have highly negative prejudices. Persuasion is not likely to be at all effective in such endeavors, but prolonged face-to-face contact in a cooperative situation might be. Then again, it might not. When considering the power of social influence, our tendency to conform, comply, and obey, and our susceptibility to persuasion, it would be dangerous to assume that we are all highly plastic, spineless, malleable, nonopinionated, compliant, and obedient. Some are; others, not so much.
Cognitive Dissonance
Another source of attitude change, as we saw in Chapter 6, is cognitive dissonance. Cog- nitive dissonance describes a situation where there is conflict between behavior, beliefs, or attitudes. The dissonance model predicts that people will change their attitudes to con- form to their behaviors when there is a conflict between the two, but only when there is insufficient justification for the behavior and when the behavior has been engaged in willingly. Thus, in dissonance experiments, subjects who are paid significant amounts for dissonant behavior, or who are forced to comply, show little attitude change later.
In studies where threats are used to force subjects to engage in dissonant behavior, cog- nitive dissonance theory makes an interesting prediction: Those who are exposed to the most severe threats for engaging—or not engaging—in some dissonance-inducing behav- ior will experience the least amount of dissonance. They would be expected to change their attitudes—and their behaviors—less than those exposed to milder threats.
The most powerful forms of persua- sion are those that succeed in changing attitudes. That this will then result in a change in behavior is the hope of all politicians as they, like this man, try to persuade us.
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CHAPTER 10Section 10.2 Attitudes and Attitude Change
To study this prediction, Wan and Chiou (2010) selected 218 college students identified as having a strong inclination toward online gaming addiction. They had these students play a new and highly engaging online game and then asked them, individually, to convince a younger adolescent that the game was not fun. They were instructed to continue until they had succeeded in convincing the “subject.” In the “severe threat” manipulation, sub- jects were told that if they were unsuccessful in convincing the adolescent to agree with them, their parents would be informed of their addiction inclination. In the “mild threat” manipulation, subjects were told that their academic advisors would be notified if they gave up the persuasion task before completing it.
As expected, subjects in the severe threat condition were far less likely to have changed their positive attitudes toward the online game. Because of the severity of the threat, their dissonant behavior was amply justified. In contrast, those exposed to mild threats would be expected to experience more dissonance because their behavior would not be so easily justified. As predicted, they were more likely to change their attitudes.
The implication is that if you resort to severe threats to coerce someone to do or not do something, you are less likely to get them to change their attitudes and subsequent behav- ior than if you can bring about the same behavior with less coercion—whether it be a reward or the threat of punishment.
Attribution and Attitude Change
As we saw in Chapter 6, our attributions for our behaviors and feelings and for those of others (the reasons we ascribe to them) provide one explanation for attitude change in dissonance situations. In a sense, we are like naive scientists observing our own behavior, the behavior of others, and the circumstances surrounding behavior. And as we observe, we make inferences about ourselves and others, attributing causes to the behaviors we observe. In some cases our attributions are dispositional attributions (they involve char- acteristics of the actor); in others they are situational attributions (they involve character- istics of the situation); and perhaps in many cases we arrive at mixed attributions.
An attribution-based explanation of attitude change following dissonant behavior may be worded as follows: If I willingly do A without compulsion or reward and am then asked to express my attitudes about doing A, I will most likely attribute my behavior to the fact that I believe that doing A is right, good, and consistent with my attitudes. If, however, I am compelled to do A against my inclinations, I can attribute my behavior to causes within myself or to the situation. If the situation justifies my behavior (the reward is suf- ficient or the threat is compelling enough), I will likely invoke a situational attribution and I won’t change my attitude. If the situation doesn’t justify my behavior, I need to attribute it to a personal characteristic (a disposition). The result is that I may change my attitude toward the activity.
Overjustification Attribution theories of attitude change in situations of forced compliance (dissonance- creating situations) maintain that when there is low justification for engaging in dissonant behavior, subjects infer that they did so because they wanted to. In contrast, when there is
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CHAPTER 10Section 10.3 Antisocial Behaviors
high justification, they attribute their behavior to external circumstances (compulsion or reward, for example).
Lepper and Greene (1975, 1978) and others have also investigated the effects of justifica- tion on consonant behavior. These authors have proposed an overjustification hypothesis which says, in effect, that large external rewards for behavior that is initially intrinsically motivated may undermine our attitudes toward the behavior. For example, if you sing songs because you like singing (intrinsic motivation: positive attitudes toward singing), and later some misguided individual promises you too high a reward for singing, you might in the end come to like singing much less.
How does this hypothesis follow from attribution theory? Bright and Penrod (2009) describe the process as follows: Given our tendency to attribute our behaviors to intrinsic or extrinsic factors, following a behavior for which external justification is very salient (a behavior that is externally overjustified), we are likely to attribute that behavior more to external causes than to internal causes. Having done so, we modify our attitudes (internal causes of behavior) and become less positively disposed toward the behavior.
This analysis might seem to contradict common sense. We have long assumed that people like to do things that are highly rewarded, and have perhaps naively assumed that if we increase rewards associated with a behavior, positive attitudes toward that behavior should also increase. But research on the overjustification hypothesis indicates that these beliefs are wrong at least some of the time.
10.3 Antisocial Behaviors
And how do we justify our antisocial behaviors—behaviors like aggression and vio-lence and unbridled competitiveness and apathy in the face of human suffering? Do external rewards serve to justify and explain these behaviors? Or is there something in our dispositions that explains them?
Aggression and Violence
A popular stereotype of North American males is that of assertive, intrusive, domineer- ing individuals bent on achieving their goals even at the expense of others. This view is based on the observation that aggression, defined as an action deliberately intended to do harm or undertaken with no consideration for the harm it might cause others, is basic to organized competitive sports such as football and hockey, is a key to success in the busi- ness and academic worlds, is one of the main themes of the entertainment media, and is characteristic of much human interaction.
Theories of Aggression It is important to note at the outset that strong assertiveness and competitiveness are not instances of aggression when they are not intended to inflict harm on others; nor are they undesirable in all circumstances. While aggression may involve violence—actual physical
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CHAPTER 10Section 10.3 Antisocial Behaviors
damage to persons or property—it might also be entirely passive—as when Iseult, in the opening tale of Tristan and Isolde, tells Tristan the fatal lie: The sails are black (Figure 10.5).
Frustration-Aggression A number of beliefs have dominated social psychology’s attempts to understand and explain aggression. Among them is Dollard and Miller’s frustration-aggression hypothesis—the contention that aggression is the result of anger and the most important cause of anger is frustration (Dollard, Miller, Doob, Mowrer, & Sears, 1939) . To be frustrated is to be prevented from reaching a goal. The Dollard and Miller hypothesis argues that, following frustration, anger is experienced; but anger will result in aggression only if a suitable object or person releases the aggression (Figure 10.6).
This explanation of aggression has often been used to explain terrorism. The assumption is that terrorism, an extreme form of aggression, may be linked to the frustration that accompanies poverty, lack of opportunity, and repression (for example, Zinchenko, 2009). In support of the frustration-aggression hypothesis, Fischer, Greitemeyer, and Frey (2008) report that higher unemployment is associated with higher measured aggressiveness.
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Figure 10.5
An aggression continuum. Social psychology defines aggression as actions intended to harm others or to achieve one’s goals without consideration of others. Thus, in a strict sense, asser- tive, competitive, intrusive, domineering, and even violent behaviors (such as might be evi- dent in sports) are not examples of aggression unless they are intended to do harm. Terrorism, a form of violence perpetrated against civilian groups, is an extreme form of aggression. Rolling pins can be too.
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CHAPTER 10Section 10.3 Antisocial Behaviors
Territoriality Another explanation, attributed to ethologists, is based on the assump- tion that we are by nature aggressive. This explanation relies heavily on observations of aggression among nonhuman animals. It assumes that since aggression appears to be common among other animals, it must have a biological basis.
According to this theory, certain stimuli in the environment serve as releasers for aggres- sion. In some cases, the stimuli are highly specific and have clear survival or reproductive significance, as when bighorn sheep fight for the right to mate. In other cases, the stimuli are less specific, as in the case of territoriality. For example, male chimpanzees patrol defined geographic areas, intent on aggressively repelling any encroachment by males from other communities. Those who violate their boundaries risk death (Amsler, 2010). The survival value of many aggressive behaviors in nonhuman animals and their frequent instinct like specificity (that is, the fact that aggression usually occurs only in response to specific conditions) provide strong evidence that aggression in animals is at least partly genetically based.
The situation with humans is not as clear. Although there is a possibility that we have (or had) instinctual tendencies toward aggressiveness, perhaps predicated on territoriality, learning and environment affect so much of our behavior that “instinctual” tendencies are difficult to isolate. Some argue that many wars—such as the Palestinian conflict—reflect
anger
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Figure 10.6
The Dollard and Miller frustration-aggression hypothesis. According to this model, frustration leads to different degrees of anger, ranging from mild irritation to blind fury. Whether it also leads to aggressive behavior depends on the situation as well as on the depth of the emotion.
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CHAPTER 10Section 10.3 Antisocial Behaviors
territoriality (Fields, 2010). Others suggest that gang conflict might also be associated with territoriality (Deuchar & Holligan, 2010).
Still, the fact is that there are human societies where aggressive behavior is at an extreme minimum (the Zuni, the Hutterites, and the Amish, for example); and there are others where it is at the opposite extreme (the Ik of Uganda; the Mundugumor of New Guinea; the Yanomamo of the Amazon). Although the existence of peace-loving societies does not prove that we have no genetic tendencies toward aggression, it does indicate that environ- mental and social factors are important.
Social Learning Social learning theory (see Chapter 4), a widely supported theory, argues that aggressive behavior is often learned as a result of observing aggressive models.
In a classic study that looked at the effects of aggressive models on children, Bandura, Ross, and Ross (1961) exposed 3- to 6-year-old children to one of three experimental conditions. One group saw an adult being physically and verbally aggressive with a large, inflated “Bobo” doll (punching it, striking it with a mallet, kicking it, sitting on it, while making aggressive comments like “sock him in the nose. . . ,” “throw him in the air. . . ,” “knock him down”). A second group watched as the experimenter totally ignored the doll. And a control group saw the Bobo doll only in the testing part of the study, during which the children were observed as they interacted with the doll or played with other toys.
The results of this study clearly illustrate the effect of aggressive models. When left alone with the doll, children exposed to the aggressive model were significantly more aggres- sive than children exposed to nonaggressive models. And often, their aggression was pre- cisely imitative: If the model punched the doll, that is what they did; if the model kicked the doll instead, then that, too, is what they did. And, strikingly, those exposed to nonag- gressive models engaged in far less aggressive behavior than those not exposed to any models at all (Figure 10.7).
This study provides strong support for a social learning theory of aggression. And, in fact, many predictions based on social learning theory have been supported by research. For example, we would expect that children who observe violence and aggression would themselves be more aggressive. In fact, that is often the case: Children who witness parental violence and abuse are more likely to be aggressive as adolescents (Ferguson, Miguel, & Hartley, 2009). And there is evidence, as well, that violence in children’s tele- vision programs tends to increase aggression among viewers (Linder & Gentile, 2009; Strasburger, 2009).
Physiology We know that aggression, like all emotions, also has a physiological basis. For example, it appears that aggression may be associated with hormones (injections of testosterone increase aggressiveness in monkeys); with olfaction (certain strains of mice respond aggressively to other mice who’ve been smeared with urine from mice that would ordinarily be aggressed upon); with brain damage or dysfunction or with stimulation of appropriate areas of the thalamus (rage can be produced in cats as a result of electrical stimulation); and with certain drugs (alcohol disinhibits aggression and is involved in a large number of violent crimes).
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CHAPTER 10Section 10.3 Antisocial Behaviors
Research suggests that at least five neurotransmitters and two hormones, the most impor- tant of which is testosterone, may be implicated in serious violent crimes (Beaver, 2010). But the fact that aggression has a physiological basis is not an adequate explanation for aggres- sive behavior because all aspects of human behavior have physiological bases. Neverthe- less, knowledge of the physiological underpinnings of aggression, and of how these interact
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Figure 10.7
In the Bandura, Ross, and Ross (1961) study, children exposed to violent models consistently behaved more aggressively with the Bobo doll.
frustration- aggression
aggression following
impediments to reaching a goal
territoriality
aggression based on instinctual tendencies
social learning
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Figure 10.8
Four explanations for aggression. These aren’t mutually exclusive. Aggression is often a func- tion of several underlying factors.
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CHAPTER 10Section 10.3 Antisocial Behaviors
with the environment to produce aggression and violence, may prove useful in controlling extremes of violence (using psychosurgery and drugs, for example). (See Figure 10.8.)
Violence in Society The most obvious instances of aggression in society are those involving overt acts of vio- lence: rape, homicide, assault, and destruction of property. Interpersonal violence, which includes the first three of these, is committed primarily by males. The extent to which these acts can be attributed to frustration, deprivation, pain, or sex-related factors, and the extent to which character and personality disorders or other factors are involved, is not clear. There is little doubt, however, that each can play a significant role.
The incidence of violent crimes in Western industrialized societies appears to have declined somewhat during the last decades. Still, the incidence of violence is high, with a total of 467 violent crimes per 100,000 U.S. population in 2007 (U.S. Census Bureau, 2010c; Figure 10.9).
Violence in society is reflected not only in crime, but in international aggression as well. In the last century alone, well over half of all nations have been involved in war. Many still are. And while nations fight, so do individuals within families. Violence in the home is not always obvious. Child abuse presents one inexact index; the fact that 25 percent or more of all homicides and assaults involve members of the same family provides a second index. In fact, violence among intimate partners, surely a prime source of aggressive models for children, is alarmingly high: 260 acts of rape, robbery, assault, and homicide per 100,000 population in 2007, with almost 90 percent of these acts carried out against women (Fig- ure 10.10). That year, 1,185 women and 346 men in the United States were killed by their
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Figure 10.9
Number of violent crimes per 100,000 population in the United States in 2007. U.S. Census Bureau (2010c). Statistical Abstract, Table 295.
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CHAPTER 10Section 10.3 Antisocial Behaviors
partners; over half a million women and nearly as many men were victims of reported physical assault (U.S. Census Bureau, 2010c).
Bystander Apathy
In the Monty Python movie The Life of Brian, Brian unintentionally inspires a group of rabid followers who think he is a messiah and who devotedly follow him around, convinced that every little thing that happens around him is a miracle. Increasingly frantic to be rid of this mob, he yells at them, “Look. You’ve got it all wrong. You don’t need to follow me. You don’t need to follow anybody! You’ve got to think for yourselves. You’re all individuals!”
“Yes, we are all individuals!” they respond in chorus.
“You’re all different,” says Brian.
“Yes, we are all different!” they respond. Except for one small voice from somewhere in the crowd. “I’m not,” it says.
“Shh! Shhhh! Shhh!” Brian’s followers respond.
Just another movie? Or an accurate reflection of mob psychology and the effects of social pressure? How much of what we think and do is determined by the groups of which we are part?
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Figure 10.10
Number of violent crimes committed against intimate partners in the United States in 2007. U.S. Census Bureau (2010). Statistical Abstract, Table 307.
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CHAPTER 10Section 10.3 Antisocial Behaviors
The classic relevant case in social psychology literature is the story of Kitty Genovese, who was brutally attacked as she returned home from work at 3 o’clock one morning (Latané & Darley, 1968). What made her story remarkable was that 38 of her neighbors in Kew Gar- dens in New York supposedly came to their windows when she cried out in terror; none came to her assistance, even though her stalker took over half an hour to murder her, even leaving once and returning later to continue his attack. Initial reports are that no one even so much as called the police. She died.
The Bystander Effect This episode has been widely reported and has served as the basis for the conclusion that being part of a large group witnessing an act that requires intervention often serves to inhibit helping behavior. And although this appears to be true under some circumstances, unfortunately the Kitty Genovese case has often been exaggerated. Later investigation uncovered that there were considerably fewer than 38 eyewitnesses to the murder (some only heard the attack), that Kitty Genovese had been involved in loud altercations on other occasions, and that one witness did, in fact, call the police (Manning, Levine, & Col- lins, 2007).
Still, there are other examples of what social psychologists call the bystander effect. Most of us would prefer to believe that the more people who witness an event where someone desperately needs assistance, the more likely it is that one of them will help. Sadly, it appears that we are a lot like the mob in The Life of Brian: In some circumstances, the more witnesses there are, the less likely it is that someone will intervene.
Latané and Darley (1970) conducted a series of experiments investigating the alleged apa- thy of bystanders. In one series of studies, subjects alone in a room overhear an epilep- tic seizure apparently suffered by another “subject” (in fact, a tape-recorded “seizure”). Experimental conditions are such that subjects either think they’re the only ones listening to the person having a seizure, or they believe that there are other witnesses in different rooms. The dependent variable is whether or not the subject reports the seizure or other- wise tries to assist, and how long it takes before helping behavior occurs.
As Figure 10.11 shows, all subjects who thought they were alone with the victim responded; in contrast, when subjects thought there were four others besides the victim, only 62 per- cent responded.
In another experiment, subjects were left in a room supposedly to wait for an interviewer (Latané & Darley, 1968). They were asked to fill out a questionnaire while waiting. Shortly thereafter, artificial smoke was blown into the room through a wall vent, continuing in irregular gusts, eventually filling the room, irritating the eyes, and making breathing dif- ficult. If subjects had not reported the smoke after 6 minutes, the experiment was discon- tinued and subjects were debriefed. In one experimental condition, subjects waited alone; in another, they waited with two other subjects; and in a third, they were paired with two experimenter’s confederates who had been instructed not to react to the smoke but to continue to fill out their questionnaires.
The results of these experiments are as expected: Subjects alone reported the smoke 75 percent of the time; subjects paired with two other subjects reported it only 38 percent of
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CHAPTER 10Section 10.3 Antisocial Behaviors
the time and took longer before doing so. Most striking, only 1 of 10 subjects paired with passive assistants reported the smoke (Figure 10.12).
An Explanation These studies indicate that individuals who have reason to believe themselves the only witnesses and hence the only immediate sources of intervention are more likely to involve themselves, either by reporting a potentially dangerous situation or by offering direct assistance. But when there are a number of apparent witnesses, people are more reluctant to become involved. However, this doesn’t necessarily mean that witnesses remain apa- thetic. In fact, there is considerable evidence that they do care. Subjects who did not report the “epileptic seizure” were often visibly shaken, their hands trembling, their faces pale and drawn.
A number of factors may be responsible for the greater reluctance of people to become involved when others could also be involved. They may not see themselves as the most competent; perhaps they simply assume that someone else has already intervened;
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Figure 10.11
Effect of group size on the likelihood of responding in an emergency. Based on Latané & Dar- ley (1970).
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CHAPTER 10Section 10.3 Antisocial Behaviors
perhaps, too, there is a fear of making a wrong judgment and of appearing foolish.
Darley and Latané (1968) attribute the bystander effect to one of three sources (or a combination of these): a process of diffusion of responsibil- ity, where the presence of others reduces the cost of nonintervention; a process of social influence, where the nonintervention of others leads the subject to misinterpret the serious- ness of the situation; and a process of audience inhibition, where the presence of others brings about fear of making a wrong decision and act- ing unwisely.
How Common Is the Bystander Effect? It is perhaps reassuring that many recent stud- ies have not found a bystander effect, or have found a considerably less dramatic one than might have been expected. For example, McMa- hon and Farmer (2009) found that a majority of student athletes would be willing to intervene in a case involving sexual violence. Reluctance to do so was often related to lack of skills required to
Bystanders often ignore the plights of those who need help, especially if there are others around and if the cost of intervention is potentially high. Reassuringly, there are those, like this man, who gladly help.
0 20 40 50 6010 30 70 80
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Figure 10.12
Effect of group membership in emergency situations. In the Latané and Darley (1968) study, only 1 out of 10 subjects reported the smoke when paired with two unalarmed confederates. Seventy-five percent reported it when left alone.
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CHAPTER 10Section 10.4 Prosocial Behaviors
intervene. Whether a person becomes a rescuer or remains a bystander may depend on level of moral development, explains DeZalia (2009).
Willingness to help is often related to the seriousness of the situation. Extreme emergen- cies are often less likely to elicit immediate assistance than are more common occurrences where the assistance required is less costly. Emergencies involving violence may present a potential danger to those who would render assistance; in addition, these usually present unfamiliar situations to which a bystander might not know how to respond.
As Latané and Darley (1970) note, before bystanders intervene, they must notice an event, interpret it as an emergency, make a decision as to their personal responsibility, select a form of assistance, and implement that assistance. When Kitty Genovese was murdered, not all of the witnesses interpreted the situation as an emergency. Manning, Levine, and Collins (2007) report that three of the five witnesses who testified at the murder trial of the assailant reported that they didn’t immediately conclude that a murder was taking place. And none of the court witnesses actually saw the stabbing. Nor is it likely that all who saw the situa- tion as an emergency would then decide to take personal responsibility for bringing assis- tance—but one actually shouted and apparently frightened the attacker away, although he returned later. Others might have thought that someone else must have called the police— and apparently someone had! In the end, the incident, shocking though it might be given our implicit beliefs in the goodness of human nature, is not entirely surprising.
Choosing a form of assistance, other than calling on someone else (the police) for assis- tance, also presents a real problem. The man who was killing Kitty Genovese might not have hesitated to attack anyone else who might try to come to her assistance directly.
In summary, the Kitty Genovese case presents an extreme in which the possibility of inter- vening and the desirability of doing so are difficult and costly. It is not surprising that the likelihood of intervention is lessened by the presence of others who might also intervene. In fact, it would be unintelligent to react without taking into account how other people are reacting. That, in a nutshell, is fundamental to understanding the nature of social influence.
10.4 Prosocial Behaviors
The influence of bystanders is not always apparent only in apathy and nonintervention: There is considerable evidence that real or imagined bystanders can have a powerful effect on prosocial behaviors like helping and giving. For example, Potter, Moynihan, Sta- pleton, and Banyard (2009) found that exposing students to models engaging in prosocial behavior—in this case, having to do with intervening in cases of sexual violence—increased the likelihood that the students would later try to help if they witnessed similar episodes.
Altruism
The apathy and nonintervention sometimes characteristic of situations in which a number of bystanders are involved are directly opposite to altruistic behaviors (self-sacrificing, helpful behaviors).
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CHAPTER 10Section 10.5 Interpersonal Relationships
Altruism is not uncommon among animal species. When a honeybee stings an intruder, it sacrifices its life for the hive—as might, also, a bird that noisily signals an approaching hawk. While these behaviors might seem contrary to the basic biological law of survival of the fittest, they really aren’t. That’s because this law applies not to individuals but to species—or, more specifically, to the genetic material that defines a species. This form of self-sacrificing altruism among animals actually increases the likelihood of survival of the species’ genetic material. The death of a single individual is a small price to pay for the survival of a swarm or a flock.
Altruism among animals has led to a sociobiological theory of altruism championed by Richard Dawkins (1976/2006). According to this theory, altruism is nothing more than genetic selfishness. Genes, Dawkins explains, can be thought of as having a selfish desire to become immortal through reproduction and survival. As a result, they push organ- isms toward behaviors designed to ensure the survival of the genetic material of that spe- cies—though not necessarily of the individual that carries the genes. Thus, if an altruistic act increases the probability of reproduction of genes carried by the species, the survival needs of the species have been served. So a man might take a risk in trying to save another if there is a chance that both will survive; but there would be no net genetic advantage to being altruistic if one or the other will surely die.
Biology clearly doesn’t explain all altruism. Nor does it explain the fact that some people willingly help those in distress while others don’t. In addition to this biological altruism, there is what is labeled reciprocal altruism, in which an individual behaves altruistically with the expectation that others will reciprocate. For example, a monkey will willingly pick parasites off another’s back—on the surface, a selfless, altruistic act. But later, the parasite-picking monkey will turn its back and expect the other to reciprocate.
We are sometimes a little like monkeys, social psychologists inform us: We sacrifice and do good things for others in the expectation that we might one day need them to recipro- cate. Some donate blood at least partly for that reason. Also, as Buchanan and Bardi (2010) show, we are sometimes altruistic because it makes us feel good—in which case, our altru- ism is not entirely selfless. They had participants perform altruistic acts (acts of kindness) at random over a 10-day period. Measures taken before and after this period indicated that their life-satisfaction scores had improved significantly during this period.
Studies of altruism indicate that our altruistic behavior often depends on how altruistic we think other people are (Ellers & van der Pool, 2010). We are more likely to be altruis- tic if we think others are, or would be, under the same circumstances—a sort of positive bystander effect. These studies also reveal that altruism is often related to the status of the actor, with higher-status individuals engaging in more altruistic behaviors (Liebe & Tutic, 2010).
10.5 Interpersonal Relationships
Altruism, by definition, goes beyond simple acts of warmth and kindness: It implies behavior where there is significant disadvantage to the doer and clear potential advantage to the receiver.
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CHAPTER 10Section 10.5 Interpersonal Relationships
Many of our positive social behaviors, kind and selfless as they might seem, are not altru- istic: They present us with no significant disadvantage. In fact, much of our behavior is governed by a desire to establish and maintain close relationships with others. Sometimes we are nice just because we want other people to like us: We are attracted to them and we want them to be attracted to us.
The Rules of Attraction
Interpersonal attraction, social psychologists tell us, seems to be strongly influenced by three things: proximity, similarity, and physical attraction.
Propinquity Physical proximity (often referred to as propinquity in social psychology) is closely related to similarity. People in close proximity often attend the same churches, colleges, and clubs and go to the same beaches, bars, and bingos. These people are likely to be similar in a lot of important ways. And ties among individuals who live in close proximity tend to be more common and much stronger than among those more physically distant (Hipp & Perrin, 2009).
Similarity Do opposites attract? Some early research speculated that people are attracted to each other on the basis of their differences. Submissive people might be attracted to dominant people. Each might fulfill certain needs the other has. But it is not as logical to assume that a highly aggressive individual will be attracted to a highly pacific individual; that an extrovert will naturally gravitate toward an introvert; that liberals and conservatives will love each other; that, to carry the argument to its illogical extreme, the more dissimilar two individuals are, the more they will love each other.
Research suggests that the opposite is more often true. Newcomb (1961) provided a house for 17 male university students so that he could study friendship patterns among them. Not surprisingly, roommates, regardless of similarity of interests and beliefs, tended to be attracted at the beginning. But as time passed and students got to know each other better, similarity gradually emerged as the most important factor in determining friendships.
A study of online attraction confirms these findings. Antheunis, Valkenburg, and Peter (2010) looked at interaction patterns and social attraction among 704 members of a social network- ing site very similar to Facebook, MySpace, and Friendster. They found that participants used three different strategies to reduce uncertainty about other members’ attitudes, emo- tions, and behavior: passive strategies such as simply observing how the target person inter- acts with others; active strategies such as asking other people about the target person; and, most effective, interactive strategies where the two people interact directly. Interactive strate- gies often involve self-disclosure, which tends to elicit self-disclosure in the other person.
Results of this study indicate that in an online situation, knowing important things about the other person (reduction of uncertainty) is closely related to social attraction.
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CHAPTER 10Section 10.5 Interpersonal Relationships
Furthermore, degree of attraction is closely related to how similar each person thinks the other is.
Physical Attractiveness Physical attractiveness, too, is often an impor- tant variable. Walster, Aronson, Abrahams, and Rottman (1966) arranged for an elaborate “dat- ing” experiment at the University of Minnesota involving 376 men and 376 women who were to attend a dance. Participants were unaware that the dance had been arranged for experimental purposes. They were simply told that they would be “computer matched” with a partner and were asked to fill out questionnaires for that pur- pose. Meanwhile, experimenters surreptitiously assigned them physical attractiveness ratings so
as to divide them into three groups: ugly, average, and attractive. (In this age’s more polit- ically correct climate, it is unlikely that researchers would use the label ugly for those less physically attractive.)
Participants were then matched randomly except that no woman was matched with a shorter partner. Of the 376 pairs thus formed, all but 40 actually attended the dance. Dur- ing the intermission, some 2 ½ hours after the start of the dance, subjects were asked to fill out an apparently anonymous questionnaire—which, of course, was not at all anony- mous. It dealt with how much they liked their date, how attractive the date was, how comfortable the subject felt, how much the date seemed to like the subject, how similar the subject thought the date was in terms of attitudes and beliefs, how much effort each was putting into making sure that the other had a good time, and whether or not they were likely to date again. Actual frequency of subsequent dating was ascertained some 4 to 6 months later by contacting all subjects directly.
The most important finding from this study was that of all the measures employed (intel- ligence, self-acceptance, extroversion, and a number of other scores in student files based on standardized tests such as the MMPI), physical attractiveness was the only significant variable in determining degree of social attraction. More attractive males and females were much less attracted to those classified as “ugly” or “average.” Although members of the least attractive group would , in general, date anybody, they too said they preferred those more attractive (Figure 10.13).
That physical attractiveness is perceived as exceptionally important in interpersonal attraction is underlined in a study by Toma and Hancock (2010), which found that online daters exaggerate their physical attractiveness in their self-descriptions. And the least attractive tend to exaggerate more than the more attractive.
Wilbur and Campbell (2010) presented female participants with descriptions of four prospective mates who varied in terms of physical attractiveness and ambition. They were asked to rate these men as potential short-term sexual partners, as casual dating
People who are similar in important ways tend to like each other more than those who are less similar. For this pair, the beads, the headband, and the dress are loud signals of similarity.
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CHAPTER 10Section 10.5 Interpersonal Relationships
partners, and as long-term romantic partners. In all cases, physical attraction deter- mined the man’s appeal; only for a long-term romantic relationship did degree of ambi- tion also become a factor.
Liking and Loving
Freud (1914/1955) put it very simply: “[In] the last resort, we must begin to love in order not to fall ill, and we are bound to fall ill if, in consequence of frustration, we are unable to love” (p. 95).
How likely is it that we will fall ill if we cannot love? Science does not answer this question as confidently as have the poets. But then love was the province of the poet long before science claimed it. And even now, poets may know more about love than does science. Of the wonder and joy and all-consuming nature of love, the poets have had little doubt; about its practical value, they remain less certain. “True love,” writes the poet Szymborska (1995), “Is it normal, is it serious, is it practical / What does the world get from two people
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How important is physical attractiveness in dating behavior? Strikingly, the most attractive partners in a “random” dating study were those consistently more likely to be asked out again. (Data from E. Walster, V. Aronson, O. Abrahams, & L. Rottman. (1966). Importance of physical attractiveness in dating behavior. Journal of Personality and Social Psychology, 4, 508–516.)
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CHAPTER 10Section 10.5 Interpersonal Relationships
who exist in a world of their own?” But we have little time for the poetry of love; here we deal only with its science.
Science provides us with ways of measuring, if not of completely understanding, love. For exam- ple, Rubin’s (1970) Loving and Liking Scales pro- vide a way of measuring interpersonal attraction. The scales are based on the assumption that those who like each other sense that they have things in common, evaluate each other positively, and appreciate each other’s company. Items that indi- cate liking (but not loving) are items like I think that is unusually well adjusted, or I would highly recommend for a responsible job.
Loving implies deeper feelings, feelings of intense caring, strong attachment, and intimacy. Love brings with it a degree of emotional interdepen- dence, a quality of exclusiveness and absorption. If you simply like someone, that person doesn’t dominate your thoughts and your dreams; nor are you concerned that someone else might also like the same person. Love, on the other hand, often brings with it a measure of fierce possessiveness and the possibility of jealousy and pain—perhaps the possibility of ecstasy as well. Rubin (1970) measures love with items such as I feel that I can confide in about virtually everything or If I could never be with , I would feel miserable.
A Model of Love
Interpersonal attraction is no simple thing, Stern- berg (1986) informs us. There are at least eight varieties of it: nonlove, romantic love, liking, fatuous love, infatuation, companionship, empty love, and consummate love. What differentiates these states from one another is the combination of intimacy, passion, and commitment involved in each. Accordingly, Sternberg has given us a triangular theory of love. But the triangle in this theory is not the classical male–male–female or female–female–male love triangle: It is the intimacy–passion–commitment triangle (Figure 10.14).
In this model, intimacy refers to emotions that bring people closer together—emotions such as respect, affection, and support. Feelings of intimacy are what lead two people to want to share things, perhaps to disclose personal, private experiences and feelings.
Physical attraction appears to be one of the most important factors at the begin- ning of a romantic relationship.
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CHAPTER 10Section 10.5 Interpersonal Relationships
Passion is a strong, sometimes almost overwhelming, desire to be with another person. Passion is often, although not always, sexual. Sternberg suggests that passion is a feeling that builds rapidly but then gradually subsides.
Commitment implies a decision-making process and may involve either a short-term or a long-term decision. On a short-term basis, commitment requires making the decision that
Consumate love
Companionate love
Romantic loveFatuous love
Intimacy (Disclosure, affection, close friendship)
Commitment (Decision to love and stay together)
Passion (Strong physical desire)
Figure 10.14
Sternberg’s triangle of love. Different combinations of commitment, passion, and intimacy determine the nature of the love relationship.
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CHAPTER 10Section 10.5 Interpersonal Relationships
one is in love. From a long-term point of view, commitment involves deciding to cultivate and maintain the loving relationship. In practice, this often implies a decision to share liv- ing arrangements and sometimes the raising of a family, either in marriage or otherwise.
Sternberg’s (1986) theory of love holds that it is the particular combination of these three components—intimacy, passion, and commitment—that determines the nature of the relationship. As Figure 10.15 shows, for example, empty love involves commitment but is devoid of passion or of intimacy (“Okay, we’ll stay together until the children are gone. Then adios!”). Consummate love, on the other hand, has all three components.
There is a pattern to the development of many relationships, Sternberg suggests. Two individuals might begin with nonlove—no passion, commitment, or intimacy. In time, nonlove might give way to infatuation, which has passion but no commitment or inti- macy—or perhaps to romantic love, which now adds intimacy but is still short of com- mitment. Eventually, consummate love might evolve as commitment is brought into the
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Passion “I want him. I like him. I’m his. Forever.”
“I need him . . . can’t leave. But I need to share stuff with you.”
“We’re real good friends, but we’re over the romantic stuff. We’re in it for the long haul.”
“He’s for me; he’s the one! At least for now.”
“We’ll stick it out. But just because of the kids.”
“She’s nice to talk to.”
“I just want to be with him— physically, you know.”
“Who? I didn’t notice him.” No passion, no intimacy,
no commitment
Consummate love
Figure 10.15
How can you tell whether you really are in love? One way is to analyze your relationship in terms of the Sternberg model, looking at the balance among passion (physical attraction and desire), intimacy (affection, mutual disclosure), and commitment (conscious decision to love, to share, to be together).
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CHAPTER 10Main Points
relationship. And perhaps the end result will be marriage or some other long-term commitment.
But even consummate love is not a static, unchang- ing thing. Sternberg (1986) points out that passion is usually very high early in a consummate rela- tionship. But with the passage of time, it dimin- ishes; at the same time, however, commitment and intimacy might increase. Research suggests that intimacy and commitment may be more important for a lasting love relationship than is passion (Madey and Rodgers, 2009).
A Last Word to the Poets
As we noted at the outset, it is possible that poets and sages know love better than does science. To
fear love, wrote Bertrand Russell, is to fear life, and those who fear life are already three parts dead (Russell, 1929/1970).
So, if we are not to be three parts dead, perhaps we should all heed Kahlil Gibran’s (1923) advice:
When love beckons to you, follow him,
Though his ways are hard and steep.
There is a good chance, if the philosophers and the poets are correct, that love will turn out to be the most important piece of the human puzzle.
Main Points 1. Social Psychology: The subject matter of social psychology deals with how
thinking, feeling, and behavior are influenced by the real or imagined presence of others. It looks at how attitudes form, change, and influence behavior, and it looks at human interactions, including those that are antisocial, prosocial, friendly, and loving.
2. Attitudes and Attitude Change: Attitudes are emotion-laden beliefs with strong motivational components. They may be evident in stereotypes and personal opinions, and they often reflect the human tendency to conform to majority opinions. In spite of personal beliefs and opinions, there is a tendency to obey authority (the Milgram studies) and to assume socially expected roles (the Stan- ford prison experiment). Persuasion, cognitive dissonance, and attributions are powerful forces in attitude change.
3. Antisocial Behaviors: Aggression, defined as actions intended to cause harm, can range from assertive behavior to extreme violence, such as might be evident
The ways of love, says Gibran, are hard and steep. Love carries no guarantees.
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CHAPTER 10Main Points
in terrorism. It may be motivated by frustration, instinctual impulses (as in ter- ritoriality or possessiveness), the effects of observing aggression and violence in society (social learning), and biochemical factors (hormones, drugs, brain injury, or disease). Bystander apathy is another antisocial behavior.
4. Prosocial Behaviors: Altruism implies a behavior that has a definite cost for the giver but a clear advantage for the recipient. Among animals, it is often related to survival, mating, and protection of the young and of the tribe, flock, swarm, herd, or group. In sociobiological terms, it represents a sort of genetic selfishness.
5. Interpersonal Relationships: Interpersonal attraction is influenced by physical attraction, similarity, and proximity (the last two are closely related). Opposites don’t attract; and physical attraction seems to be highly important in the early stages of establishing a relationship. Consummate love implies passion, intimacy, and commitment. Various other kinds of love are possible based on the balance that exists among these three factors.
Study Terms
aggression
altruistic behaviors
attitude
attributions
biological altruism
bystander effect
cognitive dissonance
commitment
compliance
conformity
consummate love
dispositional attributions
ethologists
frustration
frustration-aggression hypothesis
interpersonal attraction
intimacy
love
opinions
overjustification
passion
persuasion
prejudices
propinquity
reciprocal altruism
situational attributions
social psychology
stereotypes
territoriality
triangular theory of love
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Glossary
Accommodation In Piaget’s theory, the modification of an activity or an ability that a child has already learned, to con- form to environmental demands.
Acetylcholine A neurotransmitter pres- ent in the peripheral as well as central nervous system, involved in voluntary activity as well as in physiological func- tions (such as heart and respiration rate).
Action potential A pulselike electrical discharge along a neuron. Sequences of linked action potentials are the basis for the transmission of neural messages.
Active vocabulary Words actually used in speech.
Adaptation In perception, refers to a change in sensitivity resulting from stimu- lus conditions.
Adrenal glands Endocrine glands situ- ated at the top of the kidneys, involved in releasing hormones at times of stress.
Adrenaline Also called epinephrine. A substance produced by the adrenal glands, released in response to stress.
Afterimage A visual image that contin- ues after the stimulus that caused it is no longer present.
Aggression Hostile or forceful action intended to do harm; harming or hurting
another person; achieving one’s goals at another’s expense.
Agonist An agent or drug that enhances the activity of some naturally occurring substance. For example, cocaine is a dopa- mine agonist in that it appears to stimulate the activity of dopamine.
Agoraphobia Intense anxiety about, or avoidance of, unfamiliar places.
Agreeableness A “Big Five” personal- ity factor that includes the traits friendly, compassionate, and cooperative.
Alleles Each of two corresponding forms of a gene, one being inherited from each parent.
Alpha waves Slower, deeper brain waves characteristic of deep relaxation, having a frequency of 8 to 13 cycles per second.
Altruistic behavior Helping behav- ior. Selfless behavior designed to benefit others.
Amnesiacs Those who experience partial or total loss of memory, sometimes result- ing from head trauma.
Amok A primarily male disorder com- mon to Malaysia and other Southeast Asian countries, characterized by violent, homicidal episodes followed by amnesia.
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GLOSSARY
Amplitude With respect to sound waves, defined as the height of wave peaks, related to perceived loudness.
Amygdala A small structure in the lim- bic system (part of the forebrain) that is involved in emotion and aggression and that plays an important role in the process- ing and storage of memories that have to do with emotion.
Androgens Male sex hormones, the most important of which are testosterone and androsterone. Control the development and maintenance of male sexual characteristics and are importantly involved in sexual motivation.
Animistic thinking Attributing lifelike qualities to inanimate objects.
Anorexia nervosa A medical condition, not due to any detectable illness, involving an obsessive fear of gaining weight.
Anosmia Inability to detect odors.
Antagonist A drug that blocks the effec- tiveness of a neurotransmitter. For exam- ple, beta blockers are antagonists that reduce blood pressure by impeding receptivity of adrenaline receptors.
Aphagia The Latin prefixes a and ab sig- nify “against” or “opposed to.” Aphagia indicates insufficient eating.
Archetype Literally, the first or original model. In Jung’s theory, a sort of uni- versal thought, present in all our minds throughout history, but largely uncon- scious. Common archetypes relate to god, birth, marriage, even snakes—all stimuli to which we often respond in similar ways.
Archival research Describes research that relies on preexisting records such as census counts, birth records, and school achievement records.
Arousal As a physiological concept, refers to changes in functions such as heart rate, respiration rate, electrical activity in the cortex, and electrical conductivity of the skin. As a psychological concept, refers to degree of alertness or wakefulness.
Arousal theory A motivational theory that looks at how intensity of motivation is related to physiological changes.
Artificial insemination The process of introducing sperm in a female’s reproduc- tive tract without sexual intercourse.
Asperger’s syndrome A developmental disorder characterized by impaired social interactions and repetitive behavior pat- terns. Now considered one of the autism spectrum disorders.
Assimilation In Piaget’s theory, the act of incorporating objects or aspects of objects into previously learned activi- ties. The exercising of previously learned responses.
Association areas of the brain Parts of the four cerebral lobes involved in higher mental processes like thinking, learning, and remembering.
Assumption A belief that guides rea- soning and research, accepted as fact, but often unprovable.
Attention The process of focusing on some features of the environment while excluding others.
Attention deficit hyperactivity disorder (ADHD) A disorder marked by excessive general activity for a child’s age, attention problems, high impulsivity, and low frus- tration tolerance. Also termed hyperactivity.
Attitude A prevailing and consistent ten- dency to react in a given way, describable as being positive or negative and having important motivational consequences.
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GLOSSARY
Attribution theory A theory that looks for regularities in how people attribute outcomes to causes.
Attributions In social psychology, the explanations we devise for our own behav- ior or for the behavior of others.
Autism A complex developmental dis- ability marked by impairments in social interaction and communication skills. Classified as a pervasive mental disorder.
Autobiographical memory A type of declarative memory consisting of knowl- edge about personal experiences, tied to specific times and places.
Autonomic nervous system That part of the peripheral nervous system that is not ordinarily under conscious control. It regulates physiological functions such as respiration, heart rate, temperature, and digestion and includes the sympathetic and parasympathetic systems.
Average A mathematical indication of central tendency, obtained by summing the numbers that describe a characteristic and dividing by the number of cases involved. Although averages are often good descrip- tions of the characteristics of a group, they frequently do not describe individuals at all well.
Aversive conditioning A behavior modification technique that tries to condi- tion negative feelings toward a situation in order to bring about avoidance behavior.
Axon The elongated part of a nerve cell. Axons ordinarily transmit impulses from the cell body to adjoining dendrites.
Barnum effect The tendency to accept vague personality descriptions of oneself as accurate.
Basic orienting system The perceptual system whose principal function is to
provide the organism with information about position of the body, movement, and relation to the gravitational plane. Some- times called the vestibular sense.
Behavior modification The system- atic application of learning principles in attempts to change behavior.
Behaviorism A general term for approaches to psychology concerned pri- marily with the observable components of behavior (such as stimuli and responses).
Behavioristic theories Theories con- cerned with objective evidence of behavior rather than with consciousness and mind.
Beta waves Typical shallow and rapid brain waves of person who is awake, having a frequency of 13 to 30 cycles per minute.
Big Five factors A widely accepted per- sonality typology that includes extraver- sion, openness, conscientiousness, agree- ableness, and neuroticism.
Binge eating disorder A medical condi- tion characterized by episodes of uncon- trolled compulsive eating, not followed by attempts to get rid of excess food and calories.
Biological altruism Altruism presum- ably motivated by the need for genetic material to survive and reproduce.
Biological constraints Limitations on learning that result from biological factors rather than from experience.
Bipolar disorder Formerly manic depres- sion, a disorder marked by alternating cycles of depressive and manic episodes.
Blocking A phenomenon in classical conditioning in which conditioning to a specific stimulus becomes difficult or impossible because of prior conditioning to another stimulus.
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GLOSSARY
Body senses Sensory systems involved in perceptions of our body. Include the vestibular sense (balance and movement), skin senses (pain, temperature, and touch), and the kinesthetic sense (awareness of limb and body position and movement).
Brain A complex clustering of nerve cells that is centrally involved in coordinating activities and events in various parts of an organism. The human brain is reputedly the most complex structure in the universe.
Brain fag A form of study-induced mental exhaustion found primarily in West Africa, evident in depression, insomnia, anxiety, and learning problems.
Brain stem Part of the brain that con- nects the spinal cord with higher brain centers. Includes the hindbrain (medulla, pons, cerebellum) and the midbrain (retic- ular formation).
Bubba psychology An expression for folk beliefs in psychology; also referred to as naive or implicit theories. Bubba (or sometimes bubbe or bubbie) means grandmother.
Bulimia An eating disorder character- ized by episodes of binge eating followed by severe dieting and sometimes purging or the use of laxatives and diuretics or extreme exercise.
Bystander effect Phenomenon in which individuals who witness emergency situa- tions do not offer assistance or respond in other helpful ways.
Case studies A method of observation that involves the intensive examination of a single subject or unit.
Central executive system In Bad- deley’s model of working memory, the system concerned with regulating the flow of information from sensory storage,
processing it for long-term storage, and retrieving it from long-term storage.
Central nervous system The human ner- vous system, which includes the brain and the spinal cord.
Cerebellum A major brain structure attached to the rear of the brain stem, whose principal functions appear to be coordinating motor activity and maintain- ing balance.
Cerebral cortex The convoluted outer covering of the cerebrum, the main func- tions of which have to do with higher mental processes like thinking and imagin- ing. (See cerebrum.)
Cerebrum The main part of the human brain, consisting of the two cerebral hemi- spheres and covered by the cerebral cortex.
Chemical senses Senses that respond to the chemical properties of substances and gases: namely, taste and olfaction.
Chromosomes In the nucleus of all cells, the microscopic bodies that contain genes, which are the carriers of heredity.
Chunking A memory process whereby related items are grouped together into more easily remembered “chunks” (for example, a prefix and four digits for a phone number, rather than seven unre- lated digits).
Circadian rhythm A biological/behav- ioral cycle that is approximately one day long. It describes our sleep/wake and temperature cycles.
Classical conditioning A process in which the repeated pairing of a neutral stimulus with an effective stimulus even- tually leads to the neutral stimulus by itself producing a response similar to that of the effective stimulus.
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GLOSSARY
Clinical psychologists Trained psycholo- gists specializing in helping people with emotional and behavioral problems. (See counseling psychologists.)
Cocktail party phenomenon The fleeting and unconscious availability for process- ing of stimuli to which the individual is not paying attention.
Cognitive apprenticeship An instruc- tional model wherein parents, siblings, other adults, and especially teachers serve as a combination of model, guide, tutor, mentor, and coach to foster intellectual growth among learners.
Cognitive dissonance A state of conflict between beliefs and behavior or between expectations and behavior.
Cognitive theories Theories that look at intellectual processes such as those involved in thinking, problem solving, imagining, and anticipating.
Cognitivism A general term for approaches to learning concerned with intel- lectual events such as problem solving, infor- mation processing, thinking, and imagining.
Commitment The decision-making aspect of Sternberg’s theory of love; involves deciding that one is in love and resolving what to do about it.
Complexity With respect to sound waves, defined in terms of the mixture of waves emanating from vibratory sources, giving rise to subjective impressions of timbre.
Compliance Acceding to the wishes and desires of others.
Conception The beginning of life, or fertilization.
Concurrent schedule of reinforcement A situation in which two or more different
reinforcement schedules, each typically related to a different behavior, are pre- sented at the same time.
Conditioned response (CR) A response elicited by a conditioned stimulus.
Conditioned stimulus (CS) A stimulus that elicits a response after learning (condi- tioning) has occurred.
Conduct disorder A child and adolescent disorder marked by behaviors that vio- late the rights of others without apparent feelings of guilt, often evident in bullying, fighting, threatening, vandalism, theft, and so on.
Cones Conical light-sensitive cells in the retina that respond mainly to color and are used extensively in daylight vision.
Conformity A change in attitudes or beliefs as a result of social pressure.
Conscientiousness A “Big Five” person- ality factor including the traits efficient, organized, and self-disciplined.
Consciousness Awareness of one’s per- sonal identity. Self-awareness. Awareness of mental processes like thinking, imagin- ing, and feeling.
Conservation A Piagetian term imply- ing that certain quantitative attributes of objects remain unchanged unless some- thing is added to or taken away from them.
Constructivism A general term for student-centered approaches to teaching, such as discovery-oriented approaches, reciprocal learning, or cooperative instruc- tion—so called because of their assump- tion that learners should build (construct) knowledge for themselves.
Consummate love Sternberg’s label for love that is marked by passion, intimacy,
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GLOSSARY
and commitment. A deep and abiding kind of love.
Contiguity Temporal closeness. The state of being simultaneous or nearly simultaneous.
Control group In an experiment, a group comprising individuals as similar to the experimental group as possible except that they are not exposed to an experimental treatment. (See experimental group.)
Cornea The transparent coating that cov- ers the eyeball.
Correlation A statistical relationship between variables. High positive correla- tion means that high scores on one variable are generally accompanied by high scores on the second. A high negative correlation means that high scores on one are typically associated with low scores on the second.
Correlation fallacy The mistaken belief that if two variables are correlated, they must be causally related. Correlation is not proof of causation.
Correlational research Research designed to uncover relationships between variables without determining cause and effect.
Counseling psychologists Psychologists whose main function is to counsel individu- als regarding issues relating to vocational or educational choices, learning problems, rela- tionships, and mild emotional, physical, and mental disorders. (See clinical psychologists.)
Creationism The belief that present life forms were created by a supreme being.
Criterion (plural criteria) A standard, value, or goal by which something is judged; a necessary condition.
Cross-sectional study Method of inves- tigation that involves observing and
comparing different subjects, usually at different age levels.
Daydreaming Engaging in waking dreams or reveries that are mainly under the dreamer’s control.
Decibel A measure of perceived loud- ness of sounds.
Declarative memory Explicit, conscious long-term memory; may be either semantic or episodic.
Defense mechanisms A mental tactic (like repression or denial), usually unconscious, designed to avoid conflict and anxiety.
Delta waves Very slow brain waves (fre- quency of up to 4 per second) characteris- tic of deep sleep.
Delusions False beliefs that are held with absolute conviction and that cannot be changed even in the face of compelling contrary proof.
Dendrites Hairlike extensions emanating from the cell body of the neuron. Dendrites ordinarily receive impulses from adjoining axons.
Deoxyribonucleic acid (DNA) A sub- stance assumed to be the basis of all life, consisting of four chemical bases arranged in a mind-boggling number of combina- tions in the form of a double spiral (helix).
Dependent variable The variable (mea- surement, outcome, behavior) that reflects the assumed effects of manipulations of the independent variable(s) in an experi- ment. The “then” part of the if-then equa- tion implicit in an experimental hypoth- esis. (See independent variable.)
Depersonalization disorder An Axis I DSM-IV-TR disorder marked by feelings
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GLOSSARY
of unreality, as though everything were a dream.
Descriptive research Describes the char- acteristics of an individual or of a group. Designed to answer one or more questions relating to who, what, where, when, and how (for example: What is the average age at which North American children say their first word?).
Deterministic Having to do with the belief that every action has an identifiable cause that can be predicted given suffi- cient knowledge about prior events and their effects. Often contrasted with belief in free will.
Developmental psychologists Study cognitive, physical, and emotional changes that occur between conception and death.
Difficult infants A type of tempera- ment characterized by irregularity with respect to things like eating, sleeping, and toilet functions; withdrawal from unfamiliar situations; slow adaptation to change; and intense as well as negative moods.
Direct reinforcement Reinforcement that a person receives as a direct consequence of an action.
Discovery learning A learner-centered approach to teaching in which the acqui- sition of new knowledge comes about largely through the learner’s own efforts.
Discriminative stimulus (SD) Skinner’s term for the features of a situation that an organism can discriminate to distinguish between occasions that might be reinforced or not reinforced.
Dispositional attribution The inference that some internal characteristic explains a behavior.
Dissociative disorders Disorders that involve separating certain memories or thoughts from normal consciousness.
Dissociative fugue A rare disorder marked by sudden and unexpected depar- ture from one’s home and life with accom- panying amnesia.
Dissociative identity disorder Formerly multiple personality disorder, characterized by the presence of two or more distinct personalities, each of which dominates at different times.
Distortion theory A theory of forgetting that recognizes that what is remembered is often changed or reconstructed.
Dizygotic twins Twins that result from two separate eggs and that are therefore fraternal (nonidentical).
Dominant gene A gene that takes prece- dence over other genes in determining a related trait.
Dopamine A neurotransmitter centrally involved with pleasure and reinforcement and also implicated in some instances of drug addiction as well as in conditions such as Parkinson’s disease.
Double-blind procedure An experi- mental procedure in which neither the subjects nor the examiners know who is in the experimental group and who is in the control group.
Drive The tendency to behave that is brought about by an unsatisfied need; for example, the need for food is associated with a hunger drive.
Drive reduction The satisfaction of a need by eliminating the drive associated with it.
Drug tolerance Habituation to a drug. Evident in the observation that the effects of a drug often lessen with increasing use.
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GLOSSARY
Dyadic interactions Interactions involv- ing two individuals.
Dysphoria The opposite of euphoria; a common feature of drug withdrawal.
Dysthymic disorder Marked by a serious, chronic depression lasting at least 2 years.
Easy infants A temperament type marked by high regularity in behaviors such as eating and sleeping; high interest in novel situations; high adaptability to change; and a preponderance of positive moods, as well as low or moderate intensity of reaction.
Echolocation The use of sound to local- ize objects, based on the amount of time it takes an echo to return to the sound source.
Ectomorph Sheldon’s frail, thin body type, described as withdrawn and con- cerned with intellectual matters.
Educational psychologists Are con- cerned with issues relating to understand- ing and improving teaching and learning in educational settings.
Effector A specialized cell or organ that carries out a response to a nerve impulse.
Ego In Freud’s theory, the rational, reality- oriented level of human personality. It devel- ops as the child becomes aware of what the environment makes possible and impossible.
Egocentrism Based on Latin words for self (ego) and center—hence a self-centered behavior, attitude, or personality charac- teristic. Egocentric thought is character- ized by an inability to assume an objective point of view.
Elaboration A memory strategy that involves forming new associations, linking with other ideas or images.
Electra complex A Freudian stage (around 4 years) when a girl’s awareness
of her genital area leads her to desire her father and to become jealous of her mother.
Electrodermal response A measure of the skin’s conductivity, which typically increases with perspiration and therefore with heightened arousal.
Electroencephalogram (EEG) An instru- ment used to measure electrical activity in the brain.
Eliciting effect Imitative behavior in which the observer does not copy the model’s responses but simply behaves in a related manner.
Embryo The developing fetus, between 2 and 8 weeks after conception.
Emotion A synonym of feeling. A cogni- tive and physiological state describable with words such as anxious, angry, sad, con- fused, cautious, lonely, and a huge number of similar terms.
Encoding As a memory process, chang- ing sensations or other input to make mental representations.
Endocrine system A system of glands that secrete hormones whose functioning affects things such as growth, maturation, behavior, and emotion. Includes the pitu- itary, the adrenal glands, and the gonads.
Endomorph Sheldon’s large somatotype, believed to love comfort, be relaxed and sociable, and love eating.
Entity theory Dweck’s label for the belief that ability is a fixed, unchanging entity.
Eros A term employed by Freud to describe the life instinct, the urge for sur- vival and procreation.
Estrogen One of the main hormones pro- duced by the ovaries. Centrally involved
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GLOSSARY
in sexual maturation of females. Also found in males, but in lesser quantities.
Ethnic psychosis A mental disorder such as Windigo that is specific to an ethnic group.
Ethologist One who studies the behavior of animals in their natural habitats.
Event-related field (ERF) A measure of magnetic fields at the scalp relating to neural activity typically associated with specific stimuli.
Event-related potential (ERP) A measure of electrical activity in identifiable areas of the brain, corresponding to specific stimuli.
Evolution A scientific theory that holds that present life forms have developed from preexisting species through a series of modifications governed by laws of natural selection and diversification of spe- cies. “Survival of the fittest” refers to the genetic fitness of species rather than to the physical fitness of individuals; that is, spe- cies best able to reproduce are most likely to survive.
Evolutionary psychology An approach in psychology defined by its attention to biology and genetics as sources of explana- tion for human learning and behavior.
Ex post facto study A study in which the experimenter does not assign subjects to experimental conditions or exercise control over these conditions; the experi- menter simply studies participants on the basis of differences that already exist among them.
Expectancy-value theory A cognitive approach to motivation that describes decision making as involving a sort of mental calculus in which the most impor- tant factors are expectancy of success (feel- ings of self-efficacy) on the one hand, and
the values and costs associated with the various options on the other.
Experimental group In an experiment, the group of participants who are exposed to a treatment. (See control group.)
Experimental psychologists Psycholo- gists involved in the use of experimental (scientifically controlled) research.
Experimenter bias An unconscious phenomenon whereby experimenters’ expectations influence their observations. Not to be confused with experimenter dishonesty.
Explicit memory Another label for declarative memory.
Exposure therapy A form of therapy in which the patient confronts phobias or anxieties directly in the therapy session.
Extinction A conditioning procedure, typically involving presenting a CS with- out a US or withdrawing reinforcement, thereby eliminating a response.
Extraversion A “Big Five” personality factor that includes the traits outgoing, energetic, and positive.
Extrinsic reinforcement Reinforcement associated with external rewards like food, money, high grades, praise, and so on.
Factor analysis A statistical procedure for reducing correlational data to a smaller number of dimensions by grouping closely related variables.
Fading theory The belief that the inabil- ity to recall long-term memories increases with the passage of time as memory traces fade. Also termed decay theory.
Fallopian tube One of two tubes that link the ovaries and the uterus, where con- ception ordinarily occurs.
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GLOSSARY
False memory syndrome Describes the possibility that a memory—especially of a highly traumatic event—may be a memory of something that has not actu- ally occurred.
Fast mapping The learning of a concept, like a word, in a single trial.
Fetus An immature child in the uterus.
Fixation The stoppage of development at an immature developmental stage, some- times manifested in personality character- istics and emotional disorders relating to the earlier stage.
Flashbulb memories Unusually vivid and persistent recollections of the details surrounding first learning about an event that is highly emotionally significant.
Flynn effect The observation that there are gains in measured IQ over generations.
Forgetting Loss from memory over time; contrasted with extinction, which occurs as a result of cessation of reinforcement.
Free association A psychoanalytic tech- nique whereby the patient says whatever comes to mind.
Frequency With respect to sound waves, the number of waves per second in Hertz units, giving rise to the perception of pitch.
Frontal lobe Frontal part of the cere- bral cortex, centrally involved in higher thought processes.
Frustration The prevention of or interfer- ence with an activity directed toward a goal.
Frustration-aggression hypothesis Dol- lard and Miller’s belief that the most com- mon cause of aggression is the anger that accompanies frustration, which is caused by being prevented from attaining a goal.
Functional magnetic resonance imaging (fMRI) A diagnostic imaging technique that detects extremely subtle changes in magnetic fields in the human body, allow- ing technicians to view real-time, com- puter-enhanced images of soft tissue. Used extensively to diagnose disease as well as to study neural activity in the brain.
Functionalism An early American movement in psychology associated with William James. In contrast with structural- ism, it urged that psychology look at the purpose of mental activity rather than at its structure. (See structuralism.)
Gender identity disorder Persistent, overwhelming cross-gender identifica- tion and discomfort with one’s anatomical gender.
Generalize To engage in a process whereby conclusions derived under one set of circumstances are extended to other similar circumstances. The objective of most scientific investigations is to arrive at conclusions that can be generalized.
Generalized anxiety disorder Persistent free-floating anxiety and worry lasting at least 6 months.
Genes The carriers of heredity.
Genetic makeup The assortment of genes that compose the individual’s genetic code.
Genome The complete set of chromo- somes of an organism. All of an organism’s inheritable traits.
Genomics The discipline that stud- ies genomes in an attempt to estab- lish relationships between genes and characteristics.
Genotype Genetic makeup. The assort- ment of genes that compose the individu- als genetic code.
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GLOSSARY
Glial cells Cells that support neural functioning. Among other functions, they clean out debris and form protective coat- ings around nerves. (See myelin sheath.)
Gonads Hormone-producing sex glands. Testes in the male; ovaries in the female.
Group test A type of test usually used to measure intelligence that may be given to large groups at one time.
Habituation A decrease in response to a stimulus following repeated or prolonged exposure. Also used to describe drug tolerance.
Hallucinations A distortion in a person’s perception of reality. A false perception.
Hallucinogens A class of drugs, like LSD and ecstasy (MDMA), that change thought processes and perceptions and can pro- duce hallucinations.
Hawthorne effect Describes the obser- vation that individuals who are aware that they are members of an experimental group sometimes perform better simply for that reason.
Hering’s opponent process theory A theory that suggests we perceive color in terms of paired opposing groups of colors: red-green, yellow-blue, and black-white.
Heritability coefficient The proportion of the total variation in a trait that is due to heredity. High heritability means that a large proportion of the variation in a char- acteristic is caused by a variation in genes.
Hippocampus A limbic system struc- ture in the forebrain, which is involved in learning and memory.
Holistic education A label for educational approaches that attempt to remedy what is seen as the failure of traditional education
to educate the whole brain—especially the right hemisphere, which is speculatively linked with music, art, and emotion.
Holophrase A word the child uses to convey as much meaning as an adult would convey with a much longer phrase.
Hormones Chemicals that have a pro- nounced effect on growth, maturation, behavior, and emotions and that are pro- duced by endocrine glands and secreted directly into the bloodstream.
Humanism A philosophical and psycho- logical orientation primarily concerned with our worth as individuals and with those processes that are considered to make us more human.
Humanistic psychology A branch of psychology whose primary concern is with the development of the self and with the uniqueness of the individual. Some- times referred to as third force psychology; the other two forces are behaviorism and Freudian theory. (See humanism.)
Hyperphagia Derived from Latin terms meaning excessive (hyper) and eating (phagia).
Hypnosis A state characterized by height- ened suggestibility (willingness to do and to believe what is suggested by the hypnotist).
Hypothalamus A small structure at the base of the brain involved in the function- ing of the autonomic nervous system and in temperature regulation.
Hypothesis An educated guess, often based on theory, which can be tested. A pre- diction based on partial evidence of some effect, process, or phenomenon, which must then be verified experimentally.
Id In Freudian theory, all the instinctual urges that humans inherit, including eros and thanatos.
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Identification Refers to the process of assuming the goals, ambitions, manner- isms, and so on of another person.
Identity In Erikson’s theory, a term closely related to self. To achieve identity is to arrive at a clear notion of who one is.
Imaginary audience An egocentric tendency to assume that we are the focus of other people’s attention, that everyone is aware of and interested in our dress and behavior.
Imaginary playmate My imaginary play- mate is my best friend and goes everywhere with me and likes a lot of the same things I do and gets upset if I don’t say hello and . . .
Imitation Copying behavior. To imitate a person’s behavior is simply to use that person’s behavior as a pattern.
Implicit memory Also called nondeclar- ative memory. Refers to the memories that cannot be verbalized—for example, how to stay upright on a bicycle.
Impulse-control disorder Marked by the repeated inability to refrain from a behav- ior that is harmful or seriously distressful.
In vitro fertilization The fertilization of egg cells outside the womb—literally in glass (in vitro).
Incentive motivation A motivational con- cept relating to the attractiveness or subjec- tive value attached to a behavior or goal.
Incremental theory Dweck’s label for the belief that ability is changeable through work and effort.
Independent variable The variable that is manipulated in an experiment to see if it causes changes in the dependent variable. The “if” part of the if-then equation implicit in an experiment. (See dependent variable.)
Individual test A test, usually used to measure intelligence, that can be given to only one individual at a time.
Industrial/organizational psycholo- gists Psychologists concerned with applying psychological principles to workplace-related issues.
Infancy The first 2 years of life.
Inhibitory/disinhibitory effect The type of imitative behavior that results either in the suppression (inhibition) or appearance (disinhibition) of previously acquired devi- ant behavior.
Insanity A legal term based on a court decision regarding a person’s knowledge of right and wrong.
Insight The sudden perception of rela- tionships among elements of a problem situation.
Instinctive drift Refers to the tendency of organisms to revert to instinctual, unlearned behaviors.
Instincts Complex, species-specific, rela- tively unmodifiable patterns of behaviors, such as migration or nesting in some birds and animals.
Intellectual disability Commonly called mental retardation, a significant general depression in the ability to learn, usu- ally accompanied by deficits in adaptive behavior.
Intelligence quotient (IQ) A math- ematical representation of “intelligence” in which average performance is around 100.
Intermittent explosive disorder An impulse-control disorder marked by recur- ring failure to resist aggressive impulses, leading to excessive violence against people or property.
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Interpersonal attraction A degree of liking that is often preliminary to strong liking or loving.
Intimacy In Sternberg’s theory of love, refers to emotions that lead two people to want to share things.
Intrinsic reinforcement Reinforcement associated with internal sources of rein- forcement like satisfaction and feelings of competence and worth.
Introspection A once popular method of psychological investigation involving careful self-examination followed by an attempt to arrive at laws and principles that explain the introspector’s own behav- ior and can be generalized to others.
Introversion The opposite of extraver- sion: withdrawn, shy, reluctant to engage in social interaction.
Intuitive thinking Thought based on immediate comprehension rather than logical processes.
Iris The colored part of the eye; a muscle in the center of which is an opening that forms the pupil.
Kinesthetic sense One of the body senses, often referred to as the “muscle and joint sense,” consisting of receptors sensitive to movement of muscles, joints, and tendons.
Law of effect Thorndike’s law, basic to operant conditioning, which states that the effect of a response leads to its being learned or not learned.
Learning An actual or latent change in behavior due to experience.
Lens The transparent structure behind the pupil, capable of changing its shape to focus light on the retina.
Libido A Freudian term denoting sexual urges.
Limbic system A grouping of brain structures located beneath the cerebral cortex, associated mainly with emo- tion, memory, and reinforcement and punishment.
Link system A mnemonic system that requires forming linked visual images of what is to be recalled.
Loci system A mnemonic system in which images of items to be recalled are “placed” in familiar locations.
Locus of control The individual’s ten- dency to attribute responsibility for behav- ior and its outcomes to external or internal sources.
Longitudinal study Psychological inves- tigation in which the same subjects are examined over a period of time.
Long-term memory (LTM) A type of memory where material is processed so that it remains available for recall over a long period.
Love The province of poets rather than scientists. A strong, interpersonal attrac- tion, says science: a combination of pas- sion, intimacy, and commitment.
Magical thinking Thinking, often characteristic of preschoolers and young children, that is not entirely logical or scientifically valid, but rather inventive and surprising and sometimes bizarre— hence magical.
Magnetoencephalogram (MEG) A recording of magnetic fields that cor- respond to electrical activity of the brain. MEG recordings are obtained at the scalp by means of a magnetoencephalograph to yield event-related fields (ERFs).
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Major depressive disorder Disorder marked by one or more major depressive episodes.
Major depressive episode At least 2 weeks of significantly depressed mood, loss of interest, and other symptoms of depression.
Medulla The lowest part of the brain, found at the very top of the spinal cord and containing nerve centers involved in regu- lating physiological activity such as breath- ing, digestion, and heart functioning.
Melatonin A natural hormone closely tied to sleep/wake cycles. Also called the sleep hormone.
Memory The ability to retain and retrieve recollections of past events and information.
Menarche A girl’s first menstrual period.
Mental block A Freudian term for the ego’s defenses against revealing sensitive information.
Mental disorder Nonnormal patterns of behavior or thought that are associated with distress and/or significant disadvan- tage in coping with the environment.
Mesomorph Sheldon’s moderate somatotype, believed to love adventure, exercise, and activities that demand bold- ness and courage.
Metaneeds Maslow’s term for higher needs, including the need to grow, to achieve, to know truth, beauty, and justice, and to self-actualize.
Mind A term referring primarily to human consciousness. Often defined as originating from or resulting in processes of the brain associated with activities like thinking, imagining, and perceiving.
Mnemonic aids Systematic aids to remembering, like rhymes, acrostics, or visual imagery systems.
Mnemonist Professional memorizer.
Modal model of memory A widely accepted model of memory that describes three types of storage: sensory, short-term, and long-term.
Model A pattern for behavior that can be copied by someone. Also refers to descrip- tions of objects or phenomena. In science, models often serve as a sort of mental guide.
Modeling effect The type of imitative behavior that involves learning a novel response.
Molecular genetics The branch of genet- ics that deals with hereditary transmission. Concerned with how genes are copied, how mutations come about, and how genes are expressed in species characteristics.
Monozygotic twins Twins resulting from the division of a single fertilized egg— hence identical twins.
Mood disorders Mental disorders involv- ing mood disturbance—for example, bipo- lar disorder and major depressive disorder.
Motivation The conscious or uncon- scious forces that lead to behavior.
Myelin sheath An insulating, protective coating that surrounds nerve fibers and facilitates neural transmission.
Nanometer One billionth of a meter.
Narcotics Class of addictive drugs, like opium and morphine, that reduce pain and result in a sense of well-being.
Naturalistic observation Observation that takes place in naturally occurring
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circumstances or environments rather than in contrived environments, and where the phenomena being observed are not affected by the observer.
Nature-nurture controversy The debate over whether heredity or environment is most influential in determining develop- mental outcomes.
Need for achievement (nAch) The need to meet some inner standard of excellence, a personality variable that varies from one individual to another.
Negative reinforcer A stimulus that, when eliminated or removed, has the effect of increasing the probability of occurrence of the response that immedi- ately precedes it.
Nerve Bundles of fibers consisting of neurons, whose functions is the transmis- sion of neural impulses.
Nervous system All parts of the body composed of nerve cells, the function of which is to transmit messages. The major components of the human nervous system are the brain, the spinal cord, receptor systems associated with the major senses, and other nerve cells implicated in the functioning of muscles and glands.
Neurogenesis The active production of new neurons. Most prevalent during the pre- natal period but also occurs in adulthood.
Neuron A single nerve cell, the smallest unit of the nervous system and its basic structural unit. The function of the neuron is to transmit impulses, which are basically electrical but are made possible through chemical changes.
Neuroscience A biologically based sci- ence that looks at the nervous system— especially the brain—to understand con- sciousness and higher mental processes.
Neuroses A once common label for a variety of milder mental disorders charac- terized by anxiety and fear.
Neuroticism A “Big Five” personality factor that includes the traits nervous, sen- sitive, and moody.
Neurotransmitters Naturally produced chemicals that are released by nerve cells and that initiate or facilitate transmission of messages among nerve cells (for exam- ple, serotonin, dopamine, norepinephrine, and acetylcholine).
Nominal fallacy The assumption that naming something explains it.
Nondeclarative memory Unconscious, nonverbalizable effects of experience such as might be manifested in acquired motor skills or in classical conditioning.
Nonnaturalistic observation Observa- tions that occur in a laboratory or in other circumstances where the investigator deliberately manipulates or otherwise affects the phenomena being observed.
Nonsense syllables Meaningless combi- nations of vowels and consonants, like gar, lev, and kur, often used to study memory.
Norepinephrine A neurotransmitter linked with arousal, memory, and learning. Anomalies in the functioning of the nor- epinephrine system may be linked to some manifestations of depression. Also called noradrenaline.
Normal distribution A probability distri- bution that takes the form of a symmetrical bell-shaped graph and that describes the expected distribution of many events and characteristics.
Obesity Technically, a body mass index of 30 or more (computed by dividing weight in kilograms by the square of height in meters).
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Object concept Piaget’s expression for a child’s understanding that the world is composed of objects that continue to exist when they aren’t being sensed.
Observational learning Learning through imitation.
Obsessive-compulsive disorder Charac- terized by obsessions (recurring, irrational thoughts) and/or compulsions (repetitive, anxiety-causing behaviors).
Occipital lobe Part of the cerebral cortex located at the rear of the brain, involved in vision.
Oedipus complex A Freudian concept denoting the developmental stage (around 4 years) when a boy’s increasing aware- ness of the sexual meaning of his genitals leads him to desire his mother and envy his father.
Olfaction The sense of smell.
Olfactory epithelia Thin mucus mem- branes located in each nostril, containing odor-sensitive cells.
Openness A “Big Five” personality fac- tor that includes the traits inventive, curi- ous, and unconventional.
Operant An apparently voluntary response emitted by an organism.
Operant conditioning Learning that involves an increase in the probability of a response as a function of reinforcement.
Operation Piaget’s term for a thought pro- cess characterized by certain rules of logic.
Opinion A personal evaluation, good or bad, often manifested as a personal belief.
Oppositional defiant disorder A disorder marked by extremely disobedient, hostile, and defiant behavior in the face of authority.
Optic nerve Bundle of nerve fibers beginning with the rods and cones of the retina leading from the back of each eye- ball to the visual cortex via the thalamus.
Organization A memory strategy involv- ing grouping items to be remembered in terms of similarities and differences.
Overjustification Providing large exter- nal rewards for behavior that is initially internally motivated.
Ovum The sex cell produced by a mature female, consisting of 23 chromosomes rather than 23 pairs of chromosomes.
Panic attack An episode of intense fear or terror associated with feelings of impending doom and often leading to physical symptoms like heart palpitations.
Panic disorder Recurrent panic attacks, which cause the individual persistent anxiety.
Paradoxical effect Literally, a surprising or contradictory effect; used to describe the apparently sedating effect that some stimulants (such as Ritalin) have on chil- dren who suffer from excessive activity.
Paradoxical sleep Another label for REM sleep, so called because during this stage of sleep physiological functions such as heart and respiration rate are very similar to those of a waking state.
Paraphilia Intense, recurrent sexual urges that involve unusual objects or activities.
Parasympathetic nervous system Part of the autonomic nervous system that regu- lates physiological reactions that accom- pany emotional reactions.
Parietal lobe Cerebral lobes located just above the temporal lobes, between the frontal and occipital lobes. The parietal lobes are involved in sensation.
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Parkinson’s disease A central nervous sys- tem disease characterized by tremors, slow movement, and other symptoms; associated with low dopamine levels in the brain.
Passion In Sternberg’s love theory, a strong, often sexual, and sometimes over- whelming desire to be with another person.
Passive vocabulary Words that are understood but that may not actually be used in speech.
Perception The process by which sensa- tion is interpreted and becomes meaningful.
Peripheral nervous system The neural networks that fan out from the central ner- vous system to various parts of the body.
Personal fable An expression of adoles- cent egocentrism marked by the elabora- tion of fantasies, the hero of which is the adolescent.
Personality The set of attributes that characterize an individual, including tem- peramental, emotional, mental, and behav- ioral tendencies.
Personality disorders A grouping of 10 disorders marked by maladaptive and unexpected patterns of functioning that lead to distress or impairment.
Persuasion Deliberate attempts, more subtle than coercion, to influence attitudes and behavior.
Phenomenology Concerned with the world of appearance—that is, the world as it appears to the individual.
Phenotype A person’s manifested char- acteristics, resulting from the interaction of genotype with the environment. (See genotype.)
Phi phenomenon The illusion of motion created by presenting a rapid succession of slightly different static images.
Philosophy The pursuit of wisdom; the study of reality in an attempt to arrive at an accurate and unified conception of the universe and its nature. Because people are part of the universe, philosophy originally included attempts to understand humans— which is now the discipline of psychology.
Phobia An intense, irrational fear, trig- gered by any one of a number of objects or situations.
Phonetic system A powerful mnemonic system in which previously learned asso- ciations between numbers and mental images are used to recall large numbers of items forward, backward, or in any order.
Phonological loop In Baddeley’s model of working memory, one of the slave sys- tems responsible for maintaining verbal information, such as words or numbers, in consciousness.
Photons A visible light particle. In quan- tum physics, an elementary particle that is the basic unit of light and other forms of radiation.
Physiological needs Basic biological needs, such as the need for food, sex, water, and temperature regulation.
Pibloktoq Arctic hysteria, a 19th-century form of madness found almost exclu- sively among the Inuit, marked by bouts of screaming and crying and sometimes shedding one’s clothing.
Pinna The Latin word for the outer ear; the skin and cartilage that we identify as ears.
Pituitary gland A small endocrine gland found as a protrusion off the hypothala- mus. The master gland involved in control- ling functioning of other endocrine glands.
Placenta A flat, thick membrane attached to the inside of the uterus during preg-
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nancy, connected to the fetus by means of the umbilical cord.
Play Activities with no goal other than the enjoyment derived from them.
Pons A small brain structure that appears as a bulge at the front of medulla. Part of the brain stem involved in breathing and arousal.
Population In an experiment, the group to which results are to be generalized.
Positive reinforcer A stimulus added to a situation immediately after a response has occurred that increases the probability that the response will recur.
Positron emission tomography (PET) An imaging technique used extensively in medicine and in physiological and neurological research. Records changes in blood flow by detecting the distribu- tion of radioactive particles injected in the bloodstream.
Posttraumatic stress disorder (PTSD) A severe anxiety disorder resulting from exposure to a traumatic event or series of events.
Prefrontal lobotomy A seldom used medical procedure in which fibers con- necting the thalamus to the prefrontal and frontal lobes of the brain are severed.
Prejudice A preconceived attitude or opinion arrived at before a person obtains relevant facts and information.
Primary reinforcer An event that is rein- forcing in the absence of any learning, like food and drink.
Proactive interference When earlier learning interferes with the recall of subse- quent learning.
Projective measures Personality tests in which stimuli are ambiguous and testees’ responses are interpreted as reflecting unconscious aspects of personality.
Propinquity Closeness in place or time (physical proximity).
Proprioceptive sensation Sensation relating to bodily position and movement arising from receptors within the body.
Protowords The infant’s first wordlike sounds used to signify a specific person or object.
Psychiatrists Medical doctors with extensive additional training in the iden- tification and treatment of mental and emotional disorders.
Psychoanalysis An approach to psycho- therapy developed by Freud, based on the notion that emotional disorders result from unconscious conflicts and impulses.
Psychodynamic Relating to conscious and unconscious forces that influence behavior and personality.
Psychodynamic theory The elaborate psychotherapeutic system developed by Freud, based on his notion that behavior (and behavior disorders) are motivated by unconscious urges and motives and repressed memories.
Psychological hedonism The belief that humans act primarily to avoid pain and to obtain pleasure.
Psychological needs Human needs other than those dealing with basic physi- cal requirements: for example, the need to belong, to feel safe, to love and be loved, to maintain a high opinion of oneself, and to develop one’s potential.
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Psychology The science that examines behavior and mental processes.
Psychosocial development Erikson’s phrase to describe human development as a sequence of stages involving the resolu- tion of crises that are mainly social.
Puberty Sexual maturity following pubescence.
Pubescence Changes of adolescence leading to sexual maturity.
Pupil The opening in the iris that allows light to pass through the lens and into the eyeball.
Random sampling A sampling proce- dure in which each member of the popula- tion has an equal chance of being selected for the sample.
Rapid-eye-movement sleep (REM sleep) Sometimes referred to as the stage 5 of sleep, the stage during which most of our dreaming occurs.
Rational emotive behavior therapy (REBT) A cognitive/behavioral approach to mental disorder that helps the individual recognize and replace irrational beliefs.
Receptor A specialized cell or group of cells that responds to sensory stimulation.
Recessive gene A gene whose character- istics are not manifested in offspring when paired with the corresponding dominant gene.
Reciprocal altruism An apparently altru- istic behavior, but the recipient is expected to reciprocate later.
Reciprocal teaching An instructional technique that involves teaching four cognitive strategies for increasing reading
comprehension: generating questions, sum- marizing, clarifying word meanings and confusing text, and predicting what will happen next.
Reflex A simple, unlearned behavior like blinking in response to something coming toward the eye.
Refractory period A brief period after fir- ing during which a neuron is “discharged” and is incapable of firing again.
Regression A Freudian expression for the phenomenon of reverting to some of the activities and preoccupations of earlier developmental stages.
Rehearsal A memory strategy involving simple repetition, the principal means of maintaining items in short-term memory.
Reinforcement The effect of a reinforcer.
Reinforcer A stimulus that increases the probability that a response will reoccur.
Reliability The consistency with which a test measures whatever it measures.
Repression A Freudian term for the process by which intensely negative or frightening experiences are lost from con- scious memory.
Respondent A response elicited by a known, specific stimulus. An uncondi- tioned response.
Response A muscular, glandular, or mental reaction to a stimulus.
Reticular formation (Reticular activating system; RAS) That portion of the brain stem assumed to be responsible for the physi- ological arousal of the cortex as well as for the control of sleeping and waking.
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Retina The light-sensitive structure at the back of the eye, composed of rods and cones.
Retrieval-cue failure Inability to remem- ber due to the unavailability of appropri- ate cues.
Retrieval cues Stimuli like sounds, words, locations, smells, and so on that facilitate recall (that remind the individual of something).
Retroactive interference When subse- quently learned material interferes with the recall of previously learned material.
Reuptake The process by which a nerve cell recaptures some of the neurotransmit- ters it has released. Some medications and drugs function to increase neurotransmit- ter effectiveness by blocking reuptake.
Rods Elongated cells on the retina that respond mainly to brightness and are important for night vision.
Sample A subset of a population. A group with characteristics similar to those of the larger group from which they are selected.
Sapir-Whorf hypothesis The belief that language is essential for and determines thought (strong form); or the belief that language limits but does not determine thought (weak form).
Schema (also scheme or schemata) The label used by Piaget to describe a unit in cognitive structure. A scheme is, in one sense, an activity together with its struc- tural connotations. In another sense, a scheme may be thought of as an idea or a concept. It usually labels a specific activity: the looking scheme, the grasping scheme, the sucking scheme.
Schizophrenia A severe disorder involving significantly distorted percep- tions of reality, including delusions and hallucinations.
School psychologists Psychologists who deal with behavioral and learning problems affecting schoolchildren and issues relating to testing and placement of gifted or chal- lenged children.
Science An approach and an attitude toward the search for knowledge that emphasize objectivity, precision, and replicability.
Scientific method A method of inquiry involving a number of objective, logical steps designed to test the tenability of a scientific hypothesis. (See hypothesis.)
Secondary reinforcer An event that becomes reinforcing as a result of being paired with other reinforcers.
Sedatives A class of drugs, like alcohol and tranquilizers, that slow brain function and have a soothing effect.
Self-actualization The process or act of self-fulfillment—of achieving an aware- ness of one’s identity, of developing one’s potential.
Self-efficacy Judgments we make about how effective we are in given situations.
Semantic memory A type of declarative (conscious, long-term) memory consist- ing of stable knowledge about the world, principles, rules and procedures, and other verbalizable aspects of knowledge, includ- ing language.
Sensation A response to stimulation involving the activity of specialized organs such as eyes, ears, taste cells, and olfactory cells (smell). The responses of these organs are translated into neural impulses, which can then be interpreted by the brain or otherwise reacted to by the body.
Senses Specialized organs by means of which stimulation is received and felt (for
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example, organs related to sight, smell, touch, taste, and hearing.)
Sensorimotor First stage of Piaget’s stages of cognitive development. It describes how infants understand their world. They understand their world mainly in terms of the activities they per- form and the sensations that result.
Sensory memory The simple sensory recognition of stimuli such as sounds or light waves.
Serotonin A neurotransmitter, the bulk of which is found in the gut, where it regulates intestinal activity. Too low levels of sero- tonin may be associated with depression.
Sex chromosome A chromosome in sperm and egg cells responsible for deter- mining the sex of the offspring.
Sex-linked defects Defects due to the action of a gene located on the sex chromo- some, most often on the X chromosome, and most often manifested in males.
Sexual dysfunctions Problems relating to sexual desire or response.
Shaping An operant conditioning tech- nique for training animals to perform com- plex behaviors by systematically reinforc- ing progressively closer approximations to the desired behavior.
Short-term memory (STM) A memory stage in which material is available for recall for a matter of seconds; defines our immediate consciousness.
Significant In research, refers to findings that would not be expected to occur by chance alone more than a small percentage (for example, 5 or 1 percent) of the time.
Single-blind procedure An experimen- tal procedure in which either the investi- gators or the participants are not aware
of who are members of the experimental group and who are members of the con- trol group.
Situational attribution The inference that behavior has an external cause.
Skin senses Also called the cutaneous senses, the body senses consisting of skin receptors sensitive to touch, temperature, and pain.
Skinner box An experimental cham- ber devised by Skinner to study operant conditioning.
Slow-to-warm-up infants An infant temperament type marked by low activ- ity level; high initial withdrawal from the unfamiliar; slow adaptation to change; and a somewhat negative mood, with moder- ate or low intensity of reaction.
Social cognitive theory An explanation of learning and behavior that emphasizes the role of social reinforcement and imita- tion as well as the importance of the cogni- tive processes that allow people to imagine and to anticipate.
Social phobia Excessive fear of embar- rassment in social situations, often leading to avoidance.
Social psychology The branch of psy- chology concerned with relationships between individuals or between individu- als and groups.
Socialization The process of learning behaviors that are appropriate and inap- propriate for a given culture.
Somatic system Part of the peripheral nervous system concerned with bodily sensations and muscular movement.
Somatoform disorders A grouping of mental disorders characterized by physi- cal complaints that appear to be medical
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in nature but cannot be explained by injury, disease, drug abuse, or other mental disorders.
Sound waves Displacements of mol- ecules caused by vibratory events whose subjective effect is the perception of sound.
Specific learning disability A depression in the ability to learn specific things (for example, reading or arithmetic), where the learning difficulties are not related to intel- lectual disability or emotional disturbance.
Specific phobia Excessive and unrea- sonable fear brought about by a specific stimulus.
Sperm cell The sex cell produced by a mature male, consisting of 23 chromosomes rather than 23 pairs of chromosomes.
Spinal cord Main link between the brain and sensory and motor systems, closely involved in reflexes such as the knee-jerk reflex.
Statistical procedure A way of analyz- ing data (observations). Typically used in scientific investigations to determine whether a set of observations might have been expected to occur by chance.
Stereotypes Widely held attitudes and opinions concerning identifiable groups.
Stimulants A class of drugs, like amphet- amines and cocaine, that increase arousal and energy.
Stimulus (pl. stimuli) A physical stimu- lus is any change in the physical environ- ment capable of exciting a sense organ. Stimuli can also be internal events such as glandular secretions or even thoughts.
Stimulus discrimination Making differ- ent responses to related but distinct stimuli.
Stimulus generalization The transfer- ence of a response from one stimulus (situ- ation) to another.
Stratified sampling A sampling proce- dure that takes steps to ensure that sub- groups of the population are represented proportionally in the final sample.
Structuralism The first “school” in psy- chology, associated with Wilhelm Wundt, based on the notion that the mind can best be understood by analyzing its elements (looking at its component structure) using introspection. Studied such “elements” of consciousness as sensations, feelings, and images. (See functionalism.)
Substance-related disorders Disorders related to drug abuse or to the effects of various chemical or gaseous substances, including medications.
Suggestibility A characteristic of a hyp- notic state wherein subjects become exceed- ingly ready to believe whatever is suggested by the hypnotist and willing to perform whatever activities are asked of them.
Superego The personality structure that defines the moral or ethical aspects of personality.
Survey A research method that involves sampling a large group of individuals.
Susto A Latino disorder marked by listlessness, muscle tics, and anxiety and attributed to the loss of one’s soul follow- ing some trauma.
Symbolic model A model other than a real-life person. For example, books, televi- sion, and written instructions are impor- tant symbolic models.
Sympathetic nervous system Part of the autonomic nervous system that insti-
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gates the physiological responses that accompany emotional behavior.
Synapse A microscopic gap between the end of an axon and an adjacent dendrite, axon, or other cell across which neural impulses (neurotransmitters) travel.
Synaptic knob Slight enlargements on the wispy branches at the ends of axons.
Synesthesia A condition in which differ- ent sensations overlap and are processed simultaneously. A person with synesthesia might see a musical note or hear a color.
Systematic desensitization A behavior modification technique that attempts to replace undesirable responses with more desirable responses through conditioning.
Temperament A characteristic way of thinking or behaving.
Temporal lobe Cerebral structure located on either side of the cerebrum, associated primarily with speech, language, and hearing.
Territoriality Characteristic of species whose instinctual tendencies include estab- lishing and defending a geographic area.
Thalamus A small brain structure that serves as a major relay center for incoming sensory signals.
Thanatos A Freudian term denoting the death wish or death instinct.
Theory A body of information pertain- ing to a specific topic; a set of explanations for related phenomena that explains the phenomena and allows the investigator to make predictions (hypotheses).
Theta waves Slow brain waves (4 to 7 per second) characteristic of the early stages of sleep.
Third force psychology Maslow’s term for the humanistic movement in psychol- ogy—so labeled to differentiate it from the first force (behaviorism) and the second force (Freudian psychodynamic theory).
Trait Any distinct, consistent characteristic that can vary from one person to another.
Transference A psychoanalytic pro- cess whereby the patient transfers to the therapist emotions and feelings originally directed elsewhere.
Transitive inference A type of logical thinking in which an inference is made about the relationship of two objects or events by comparing them with a third rather than by comparing them directly.
Triadic reciprocal determinism Bandura’s notion that personal characteristics, behav- ior, and the environment all affect each other reciprocally—that individuals are both prod- ucts and producers of their environments.
Triangular theory of love Sternberg’s theory based on the notion that various kinds of love can be differentiated on the basis of the relative degrees of intimacy, passion, and commitment involved.
Triarchic theory of successful intelligence Sternberg’s view that intelligence involves analytical, creative, and practical abilities, as well as skill in selecting and shaping envi- ronments to maximize adaptation.
Type A related grouping of personality traits.
Umami One of the five distinct tastes humans can distinguish, variously described as savory or meaty.
Umbilical cord A long, thick cord attached to the placenta at one end and to what will be the child’s navel at the other.
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Unconditioned response (UR) A response that is unlearned, that occurs automatically.
Unconditioned stimulus (US) A stimu- lus that elicits a response without requir- ing learning.
Uterus The womb, where the infant develops prenatally.
Validity The extent to which a test mea- sures what it is intended to measure.
Variable A property, measurement, or characteristic that can vary from one situ- ation to another. In psychological investi- gations, qualities such as intelligence, sex, personality, age, and so on can be impor- tant variables.
Vestibular organ The part of the inner ear, consisting of the semicircular canals, involved in balance, body orientation, and movement.
Vestibular sense The sense, highly dependent on the semicircular canals in the inner ear, that provides us with information about balance and movement.
Vicarious reinforcement Reinforcement that results from observing someone else being reinforced. In imitative behavior, observers often act as though they are being reinforced when in fact they aren’t, but they think that the model is.
Visual constancies Properties of visual perception that enable us to perceive color, size, and shape as being constant under a variety of different conditions.
Visual-spatial sketch pad One of the slave systems in Baddeley’s model of working memory, concerned with the processing of material that is primarily visual or spatial.
Wavelength In vision, a property of light waves measured in nanometers (billionths of a meter) and related to the perception of color.
Windigo A primarily male disorder found among some Native American tribes in which the victim becomes convinced that he will become a Windigo—a person- eating creature.
Withdrawal symptoms Symptoms that result from cessation of drug use following addiction.
Working memory The Baddeley model describing how information is processed in short-term memory by means of a control system (central executive system) and systems that maintain verbal material (phonological loop) and visual material (visual-spatial sketch pad).
Yerkes-Dodson law States that the effec- tiveness of performance is an inverted U-shaped function of arousal, such that very low and very high levels of arousal are asso- ciated with the least effective behavior.
Young-Helmholtz trichromatic theory A theory that recognizes the existence of three cone systems whose different responses to light waves determine per- ception of color.
Zygote A fertilized egg cell (ovum), formed from the union of sperm and ovum, consisting of 46 chromosomes.
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- FM & TOC
- Chapter 1
- Chapter 2
- Chapter 3
- Chapter 4
- Chapter 5
- Chapter 6
- Chapter 7
- Chapter 8
- Chapter 9
- Chapter 10
- Glossary
- References
- Photo Credits
