When Does Adolescence End?
JayLee23
DevelopmentalCh9.pptx
Adolescence: Body and Mind
chapter nine
Invitation to the Life Span
Kathleen Stassen Berger | Fourth edition
1
Puberty (part 1)
Average ages and changes
Time between the first onrush of hormones and full adult physical development; begins between ages 8 and 14
Characterized by rapid physical growth and sexual maturation
Do They See Beauty?
Both young women—the Mexican 15-year-old preparing for her Quinceanera and the Malaysian teen applying a rice facial mask—look wistful, even worried. They are typical of teenage girls everywhere, who do not realize how lovely they are.
Puberty refers to the years of rapid physical growth and sexual maturation that end childhood, producing a person of adult size, shape, and sexuality.
2
Puberty (part 2)
Sequence
Hypothalamus signals pituitary to send hormones to the adrenals to enlarge the gonads that produce a rush of sex hormones.
Entire body and brain are transformed by puberty.
Puberty (part 3)
Sequence
Observable changes in girls
Nipple growth and a few pubic hairs
Increases in height while fat, especially at the breast and hips, accumulates
First menstrual period ( menarche ) is followed by more growth.
Body growth complete by four years after it began; brain growth complete by the mid-20s
Usual growth sequence for boys is growth of the testes, initial pubic hair growth, growth of the penis, first ejaculation of seminal fluid (spermarche), appearance of facial hair, a peak growth spurt, deepening of the voice, and final pubic hair growth (Biro et al., 2001; Herman-Giddens et al., 2012; Susman et al., 2010). Final height is reached by age 20.
4
Puberty (part 4)
Sequence
Observable changes in boys
Usual growth sequence is growth of the testes, initial pubic hair growth
Growth of the penis, first ejaculation of seminal fluid (spermarche), appearance of facial hair
Peak growth spurt, deepening of the voice, and final pubic hair growth
Final height by age 20
5
Puberty (part 5)
Psychological effects
Hormones instigate attraction and precipitate emotions.
Genes and earlier experiences interact with hormones.
More moodiness and psychopathy at extremes
Boys: Schizophrenia
Girls: Severe depression
Sexual thoughts can cause physiological and neurological processes, not just result from them
Puberty (part 6)
Brain development
Limbic system (fear, emotional impulses) matures before the prefrontal cortex (planning ahead, emotional regulation).
Prefrontal cortex limited in connections and engagement and may be overwhelmed with impulses.
Pubertal hormones directly affect amygdala
Puberty (part 7)
Same people but not the same brain.
These brain scans are part of a longitudinal study that repeatedly compared the proportion of gray matter from childhood through adolescence.
Gray matter is reduced as white matter increases, in part because pruning during the teen years (the last two pairs of images here) allows intellectual connections to build.
8
Puberty (part 8)
Body rhythms
Day-night cycle of biological activity occurs approximately every 24 hours (circadian means “about a day”).
Genetics influence the tendency toward evening or morning alertness.
Biology (circadian rhythms) and culture (parties and technology) work to make teenagers increasingly sleep-deprived with each year of high school.
Blue spectrum light from electronics have strong effect on the circadian system.
Sleep deprivation and irregular sleep schedules increase the risk of insomnia, nightmares, mood disorders (depression, conduct disorder, anxiety), and falling asleep while driving.
9
Puberty (part 9)
Sleepyheads
Three of every four high school seniors are sleep deprived. Even if they go to sleep at midnight, as many do, they must get up before 8 A.M. as almost all do. Then, all day they are tired.
10
Inside the Brain
Impulses, rewards, and reflection
Hormones, especially testosterone, fuel emotional impulses.
Heightened arousal occurs in and influences the brain’s reward center, especially risk-taking.
Social approval is crucial and rejection from peers is especially painful.
Puberty (part 10)
Losing Is Winning
In this game, risk-taking led to more crashes and fewer points. As you see, adolescents were strongly influenced by the presence of peers, so much so that they lost points that they would have kept if they had played alone. In fact, sometimes they laughed when they crashed instead of bemoaning their loss.
Note the contrast with emerging adults, who were more likely to take risks when alone.
12
Puberty (part 11)
Early or late?
Puberty begins between ages 8 and 14.
Influence of genes, gender, weight, hormones, and stress interact.
Onset stress matters less when friends mature at similar rates.
Leptin, a hormone that is naturally produced by the human body, definitely affects puberty onset in girls. Low leptin is a problem, as this hormone is essential for appetite, energy, and puberty. However, too much leptin correlates with obesity, early puberty, and then early termination of growth.
13
Growth, Nutrition, and Sex
Growing bigger and stronger
Each body part increases in size on a schedule.
Growth proceeds from extremities to the core.
Height spurt follows the weight spurt and then a muscle spurt occurs; these spurts precede increases in bone mass (fracture vulnerability).
Skin becomes oiler, sweatier, and more acne prone, and hair grows under arms, on faces, and over sex organs.
Growth, Nutrition, and Sex (part 1)
Remember!
The body, brain, and behavior always interact.
Sexual thoughts themselves can cause physiological and neurological processes, not just result from them.
Rising cortisol levels at puberty increase the likelihood of anger or frustration.
Emotions then increase hormones.
Growth, Nutrition, and Sex (part 2)
Diet deficiencies
Many adolescents have unhealthy diets.
Deficiencies of iron, calcium, zinc, and other minerals
Iron depletion from menstruation, intensive physical labors or sports
Nudge toward poor dietary choices from peers and environment
Growth, Nutrition, and Sex (part 3)
Body image
Eating choices and patterns are often influenced by perceptions of negative body image.
Two-thirds of U.S. high school girls are trying to lose weight; one-third think they are overweight (actual incidence is one-sixth).
Depression peaks around age 14; it decreases for many with prefrontal cortex maturation.
Growth, Nutrition, and Sex (part 4)
Eating disorders
Erratic eating, drug ingestion
Girls: Diet pills
Boys: Steroids
Common types
Anorexia nervosa
Bulimia nervosa
Binge eating disorder
Growth, Nutrition, and Sex (part 5)
Sexual maturation
Sexuality is multidimensional, complicated, and variable.
Primary sex characteristics
Parts of the body that are directly involved in reproduction, including the uterus, ovaries, testicles, and penis
Secondary sex characteristics
Observable physical traits that are not directly involved in reproduction but that indicate sexual maturity
Growth, Nutrition, and Sex (part 6)
Sexual maturation and psychological impact
Biology causes all sex characteristics, but psychology determines their impact.
Sex hormones affect the brain and many culturally influenced thoughts and behaviors reflect an increased understanding of sexuality.
Masturbation is common for both sexes.
Growth, Nutrition, and Sex (part 7)
Sexual maturation and sexual intercourse
Finnish researchers found sexually experienced 13-year-olds were more depressed, rebellious, and drug abusing; trend reversed at age 19
Sexual activity of friends is one of best predictors of sexual activity of adolescent
Every gender, ethnic, and age group has become less active than the previous cohort.
Growth, Nutrition, and Sex (part 8)
Sexual problems in adolescence
Positive trends
Decreased teen births
Increased use of protection
Decreased teen abortion
Problems
Earlier puberty and sex before age 15
Unmarried, single teen mothers
Grandmother support limited or not available
STIs
Growth, Nutrition, and Sex (part 9)
Sexual abuse
Defined as any sexual activity (including fondling and photographing) between a juvenile and an adult
Linked to wide host of subsequent problems
Most frequently affects adolescents
Forced marriage; sex trafficking
Cognitive Development (part 1)
Adolescent egocentrism
Thinking that leads young people (ages 10 to 13) to focus on self to exclusion of others
Rumination
Imaginary audience
Belief that others are watching and taking note of appearance, ideas, and behaviors; creates self-consciousness
Acute self-consciousness
24
Cognitive Development (part 2)
Personal fable
Characterized by an adolescent’s belief that his or her thoughts, feelings, and experiences are more wonderful or awful than others
Invincibility fable
Characterized by conviction that or even harmed by anything that might defeat a normal mortal, such as unprotected sex or high-speed driving
25
Cognitive Development (part 3)
Formal operational thought: Piaget
Characterized by more systematic logic and the ability to think about abstract ideas
Math: Ability to multiply unread numbers
Social studies: Ability to consider global effects and problems
Science: Ability to study invisible particles and distant galaxies
Cognitive Development (part 4)
Piaget’s balance-scale test of formal reasoning, as it is attempted by a (a) 4-year-old, (b) 7-year-old, (c) 10-year-old, and (d) 14-year-old. The key to balancing the scale is to make weight times distance from the center equal on both sides of the center; the realization of that principle requires formal operational thought.
27
Cognitive Development (part 5)
One hallmark of formal operational thought is the capacity to think of possibility, not just reality.
Hypothetical thought
Reasoning that includes propositions and possibilities that may not reflect reality
Deductive reasoning
Reasoning from a general statement, premise, or principle, through logical steps, to figure out (deduce) specifics
Sometimes called top-down reasoning
Inductive reasoning
Reasoning from one or more specific experiences or facts to a general conclusion; may be less cognitively advanced than deduction
Sometimes called bottom-up reasoning
Cognitive Development (part 6)
Dual processing
Two networks exist within the human brain
One for intuitive emotional responses
One for analytical reasoning
Impressive Connections
This robot is about to compete in the Robotics Competition in Atlanta, Georgia, but much more impressive are the brains of the Oregon high school team (including Melissa, shown here) who designed the robot.
29
Cognitive Development (part 7)
Adolescents are more likely to be intuitive thinkers because of uneven brain maturation.
Parents and teachers prefer slower, analytic thinking.
Emotional conclusions and intuition are more comforting.
With age, adolescents become more logical, less overtly optimistic, and less fatalistic.
Cognitive Development (part 8)
Social context, experience, and training in statistics and linguistics that emphasize logic become major influences on adolescent cognition.
Cognitive Development (part 9)
Does adolescent thinking have merit?
Teenage irrationality and impulsivity may be blamed on different priorities rather than a way of thinking.
Hormones and brains are less attuned to long-term consequences.
Different values may be at play.
Lust for excitement, responsiveness to peers, and willingness to explore new ideas may be adaptive in some contexts.
What do you think?
A Case to Study: Biting the Policeman
After reading the case on page 334 of your text, answer the following:
How did the adolescent’s brain development contribute to her action and reaction to the police officer?
In what way is this an example of dual processing?
What role did the adolescent’s previous childhood experiences play in her reaction to the police officer?
Secondary Education (part 1)
Student emotional and academic engagement from fifth grade to eighth grade:
Overall average was a slow and steady decline of engagement
About 18 percent were highly engaged
About 5 percent experienced precipitous disengagement year by year
A study of student emotional and academic engagement from fifth grade to eighth grade found that, as expected, the overall average was a slow and steady decline of engagement, but a distinctive group (about 18 percent) were highly engaged throughout while another distinctive group (about 5 percent) experienced precipitous disengagement year by year (Li & Lerner, 2011).
The 18 percent group are likely to do well in high school; the 5 percent group are likely to drop out, but some of them are late bloomers who could succeed in college if given time and encouragement. Thus, schools and teachers need many strategies to reach every adolescent. Various scientists, nations, schools, and teachers advocate many reforms, based on opposite but logical hypotheses.
34
Secondary Education (part 2)
Secondary education
Period after primary education (elementary or grade school) and before tertiary education (college)
Usually occurs from about age 11 to age 18, although the age range varies somewhat by school and by nation
Compulsory education until at least age 12 almost everywhere, and new high schools and colleges open daily in developing nations
35
Secondary Education (part 3)
Middle school
School for children after elementary school and before high school, usually grades 6 through 8
Academic achievement slows down and behavioral problems increase
Increased bullying
Less protective parenting
Declining achievement, especially young adolescents of ethnic minorities
Complicated friendships
Challenging academic excellence recognition
Academic achievement slows down, and behavioral problems increase.
36
Secondary Education (part 4)
Coping with middle school
Quit trying
Fixed versus growth mindset
Problems related to increased technology
Opposing Perspectives: Digital Natives
Is technology a blessing or a curse?
Technology provides such things as tools for learning and medical monitoring.
It also may facilitate cyberbullying, sexting, online harassment or predation, or Internet addiction.
Internet addiction almost always occurs with other disorders.
A View from Science Computer Use as a Symptom
Psychoanalytic theory: Mental health problems arise from deep conflicts, and thus Internet use is a symptom—not the problem.
Behaviorism: Behavior itself may be the problem.
Evolutionary theory: An enduring need to connect drives behavior.
Secondary Education (part 5)
High school
Many of the patterns and problems of middle school initially continue in high school.
After maturation reduces sudden growth and sexual impulses of puberty, adolescents are better able to cope with school.
By the end of the high school years, most adolescents are increasingly able to think abstractly, analytically, hypothetically, and logically, as well as subjectively, emotionally, intuitively, and experientially.
Secondary Education (part 6)
College bound
In theory and sometimes in practice, high schools promote students’ analytic ability.
In the United States, an increasing number of high school students are enrolled in classes that are designed to be more rigorous and that require them to pass externally scored exams.
AP and IB
In 2016, AP classes were taken by about one-third of all high school graduates, compared to less than one-fifth (19 percent) in 2003.
41
Secondary Education (part 7)
High-stakes test
Evaluation that is critical in determining success or failure
Determines if a student will graduate or be promoted
High school graduation rates increased every year in the past decade.
In 2016, 83.2 percent of U.S. high school students graduated.
Many East Asian nations have begun to phase out high-stakes tests; local autonomy is increasing.
42
Secondary Education (part 8)
Mostly Good News
This depicts improvements in high school graduation rates, especially among Hispanic youth, who drop out only half as often as they did 20 years ago. However, since high school graduation is increasingly necessary for lifetime success, current rates still lag behind the vocational demands. Future health, income, and happiness for anyone who does not complete high school are in jeopardy.
43
Secondary Education (part 9)
Alternatives to college
One-third of U.S. high school graduates do not enter college (wide range).
About three-fourths who enter community colleges do not complete AA degree in three years.
Only 37 percent of U.S. young adults have a B.S. degree.
High school graduates are unprepared for jobs.
44
Measuring Practical Cognition
Measuring practical cognition
PISA (Programme for International Student Assessment)
International test taken by 15-year-olds in 50 nations that is designed to measure problem-solving and cognition in daily life
U.S. students performed lower on the PISA compared to many other nations (in the 2012 assessments).
The PISA and international comparisons of high-school dropout rates suggest that U.S. secondary education can be improved, especially for those who do not go to college.
PIRLS and TIMSS covered earlier
45
