discussions

5/16/2019

1

Learning

Chapter 7

EXPLORING PSYCHOLOGY DAVID G. MYERS | C. NATHAN DEWALL

Chapter Overview

• Basic Learning Concepts and Classical Conditioning

• Operant Conditioning

• Biology, Cognition, and Learning

How Do We Learn? (part 1)

• Learning: Process of acquiring through experience new and relatively enduring information or behaviors

• Associative learning: Learning that certain events occur together. The events may be two stimuli (as in classical conditioning) or a response and its consequences (as in operant conditioning).

How Do We Learn? (part 2)

• Stimulus: An event or situation that evokes a response. • Conditioning: The process of learning associations,

which takes two main forms: • Classical conditioning: We associate stimuli that we do not

control, and we automatically respond (exhibiting respondent behaviors).

• Operant conditioning: We associate a response (our behavior) and its consequence (producing operant behaviors).

• Cognitive learning: The acquisition of mental information, whether by observing events, by watching others, or through language. • Observational learning: A form of cognitive learning that lets

us learn from others’ experiences.

Classical Conditioning (part 1)

• Ivan Pavlov’s early twentieth-century experiments are psychology’s most famous research. • Classical conditioning: Type of learning in which

one learns to link two or more stimuli and anticipate events.

• Behaviorism: • Psychology (1) should be an objective science that (2)

studies behavior without reference to mental processes.

• Most research psychologists today agree with (1) but not with (2).

Classical Conditioning (part 2)

5/16/2019

2

Classical Conditioning (part 3)

• Neutral stimulus (NS): In classical conditioning, a stimulus that elicits no response before conditioning.

• Unconditioned response (UR): In classical conditioning, an unlearned, naturally occurring response (such as salivation) to an unconditioned stimulus (such as food in the mouth).

• Unconditioned stimulus (US): In classical conditioning, a stimulus that unconditionally— naturally and automatically—triggers an unconditioned response.

Classical Conditioning (part 4)

• Conditioned response (CR): In classical conditioning, a learned response to a previously neutral (but now conditioned) stimulus.

• Conditioned stimulus (CS): In classical conditioning, an originally irrelevant stimulus, that, after association with an unconditioned stimulus, comes to trigger a conditioned response.

• For three decades, Pavlov’s research demonstrated associative learning, exploring five major conditioning processes: acquisition, extinction, spontaneous recovery, generalization, and discrimination.

Classical Conditioning (part 5)

• Acquisition • Initial stage • When one links a neutral stimulus and an unconditioned

stimulus so that the neutral stimulus begins triggering the conditioned response

• Extinction • Diminishing of a conditioned response • Occurs in classical conditioning when an unconditioned

stimulus does not follow a conditioned stimulus

• Spontaneous recovery • Reappearance, after a pause, of an extinguished

conditioned response

Idealized Curve of Acquisition, Extinction, and Spontaneous Recovery

Classical Conditioning (part 6)

• Generalization • Tendency, once a response

has been conditioned, for stimuli similar to the conditioned stimulus to elicit similar responses

• Discrimination • Learned ability to distinguish

between a conditioned stimulus (which predicts the unconditioned stimulus) and other irrelevant stimuli

Generalization

• Pavlov demonstrated generalization by attaching miniature vibrators to various parts of a dog’s body.

5/16/2019

3

Pavlov’s Legacy

• The consensus among psychologists is that classical conditioning is a basic form of learning.

• Why should we care that dogs can be conditioned to the sound of a tone? Many other responses to many other stimuli can be classically conditioned in many other organisms.

• Pavlov demonstrated how a learning process can be studied objectively.

• Classical conditioning is a basic form of learning that applies to all species.

Applications of Classical Conditioning (part 1)

• Pavlov’s principles are used to influence human health and well-being: • Areas of consciousness • Motivation • Emotion • Health • Psychological disorders • Therapy

• Addicts are counseled to avoid stimuli (for example, people and settings) that may trigger cravings.

• Pairing a particular taste with a drug that influences immune responses may eventually lead to immune response from the taste alone.

Applications of Classical Conditioning (part 2)

• Pavlov’s work provided a basis for Watson’s ideas that human emotions and behaviors, though biologically influenced, are mainly a bundle of conditioned responses.

• Watson applied classical conditioning principles in his studies of “Little Albert” to demonstrate how specific fears might be conditioned.

• Watson boasted that he could take any healthy infant and train the child for any career specialization, regardless of any inborn traits, but later admitted to “going beyond his facts.”

Operant Conditioning (part 1)

• Operant conditioning: A type of learning in which behavior is strengthened if followed by a reinforcer or diminished if followed by a punisher.

• Operant behavior: Behavior that operates on the environment to produce rewarding or punishing stimuli.

• In contrast, classical conditioning involves respondent behavior—automatic responses to a stimulus.

Operant Conditioning (part 2)

• Behavior operates on the environment to produce rewarding or punishing stimuli.

• Organisms associate their own actions with consequences.

• Actions followed by reinforcement increase; those followed by punishments often decrease.

Skinner’s Experiments (part 1)

• B. F. Skinner (1904–1990): Modern behaviorism’s most influential and controversial figure • Expanded on Edward L. Thorndike’s law of effect,

which states that rewarded behavior tends to recur • Developed behavioral technology that revealed

principles of behavior control • Designed and used an operant chamber (Skinner

box) for experiments that included a bar (a lever) that an animal presses (or a key or disc that the animal pecks) to release a reward of food or water, as well as a device that records these responses.

5/16/2019

4

Skinner’s Experiments (part 2) Skinner’s Experiments (part 3)

• By shaping animals’ natural behaviors, Skinner was able to teach these animals unnatural behaviors (such as teaching pigeons to walk in a figure 8, play Ping- Pong, and keep a missile on course by pecking at a screen target).

• Reinforcement: Any event that strengthens the behavior it follows.

Shaping Behavior

• Everyday behaviors are continually reinforced and shaped.

• Shaping: Gradually guiding behavior toward closer and closer approximations of the desired behavior.

• With the method of successive approximations, responses that are increasingly closer to the final desired behavior are rewarded; all other responses are ignored.

Operant Conditioning: Types of Reinforcers

• Positive reinforcement: Increases behaviors by presenting positive reinforcers. • A positive reinforcer is any stimulus that, when

presented after a response, strengthens the response.

• Negative reinforcement: Increases behaviors by stopping or reducing negative stimuli. • A negative reinforce is any stimulus that, when

removed after a response, strengthens the response. (Note that it is not punishment.)

Ways to Increase Behavior

Operant Conditioning Term Description Examples

Positive reinforcement Add a desirable stimulus Pet a dog that comes when you call it; pay someone for work done.

Negative reinforcement Remove an aversive stimulus

Take painkillers to end pain; fasten seatbelt to end loud beeping.

Operant Conditioning: Types of Reinforcers

• Primary and conditioned reinforcers • Primary reinforcer: An unlearned, innately reinforcing

stimulus, such as one that satisfies biological needs

• Conditioned (secondary): A stimulus that gains power through association with primary reinforcer

• Immediate and delayed reinforcers • Immediate: Occurs immediately after a behavior

• Delayed: Involves a time delay between the desired response and delivery of the reward

5/16/2019

5

Reinforcement Schedules (part 1)

• Reinforcement schedule: A pattern that defines how often a desired response will be reinforced

• Continuous reinforcement schedule: Reinforcing the desired response every time it occurs

• Partial (intermittent) reinforcement schedule: Reinforcing a response only part of the time; results in slower acquisition of a response but much greater resistance to extinction than does continuous reinforcement

Reinforcement Schedules (part 2)

• Fixed-ratio schedule: Reinforcing a response only after a specified number of responses

• Variable-ratio schedule: Reinforcing a response after an unpredictable number of responses

• Fixed-interval schedule: Reinforcing a response only after a specified time has elapsed

• Variable-interval schedule: Reinforcing a response at unpredictable time intervals

Intermittent Reinforcement Schedules Reinforcement Schedules (part 3)

Fixed Variable

Ratio Every so many: reinforcement after every nth behavior, such as buy 10 coffees, get 1 free, or pay workers per product unit produced

After an unpredictable number: reinforcement after a random number of behaviors, as when playing slot machines or fly fishing

Interval Every so often: reinforcement for behavior after a fixed time, such as Tuesday discount prices

Unpredictably often: reinforcement for behavior after a random amount of time, as when checking our phone for a message

Punishment (part 1)

• Punishment administers an undesirable consequence or withdraws something desirable in an attempt to decrease the frequency of a behavior (e.g., a child’s disobedience).

• Positive punishment: Presenting a negative consequence after an undesired behavior is exhibited, making that behavior less likely to happen in the future.

• Negative punishment: Removing a desired stimulus after a particular undesired behavior is exhibited, resulting in reducing that behavior in the future.

Punishment (part 2)

Fixed Variable

Ratio Every so many: reinforcement after every nth behavior, such as buy 10 coffees, get 1 free, or pay workers per product unit produced

After an unpredictable number: reinforcement after a random number of behaviors, as when playing slot machines or fly fishing

Interval Every so often: reinforcement for behavior after a fixed time, such as Tuesday discount prices

Unpredictably often: reinforcement for behavior after a random amount of time, as when checking our phone for a message

5/16/2019

6

Four Major Drawbacks of Physical Punishment

• The punished behavior is suppressed, but not forgotten. This temporary state may (negatively) reinforce parents’ punishing behavior.

• Punishment teaches discrimination among situations—perhaps only selectively decreasing the undesired behavior.

• Punishment can teach fear. • Physical punishment may increase aggression

by modeling violence as a way to cope with problems.

Applications of Operant Conditioning

• At school: Electronic technologies and adaptive learning software used in teaching and learning have helped realize Skinner’s goal of individually paced, customized instruction with immediate feedback.

• In sports: Behavioral methods are used to shape behavior in athletic performance.

• At work: Rewards have been successfully used to increase productivity and skill development.

• At home: Basic rules of shaping are used in parenting, and to reinforce our own desired behaviors.

Reinforcing Desired Behaviors and Extinguishing Undesired Behaviors

• State a realistic goal in measurable terms.

• Decide how, when, and where you will work toward your goal.

• Monitor how often you engage in your desired behavior.

• Reinforce the desired behavior.

• Reduce the rewards gradually.

Contrasting Classical and Operant Conditioning

Classical Conditioning Operant Conditioning

Basic idea Learning associations between events we do not control.

Learning associations between our behavior and its consequences.

Response Involuntary, automatic. Voluntary, operates on environment.

Acquisition Associating events; NS is paired with US and becomes CS.

Associating a response with a consequence (reinforcer or punisher).

Extinction CR decreases when CS is repeatedly presented alone.

Responding decreases when reinforcement stops.

Spontaneous recovery

The reappearance, after a rest period, of an extinguished CR.

The reappearance, after a rest period, of an extinguished response.

Generalization The tendency to respond to stimuli similar to the CS.

Responses learned in one situation occurring in other, similar situations.

Discrimination Learning to distinguish between a CS and other stimuli that do not signal a US.

Learning that some responses, but not others, will be reinforced.

Biology, Cognition, and Learning Biological Limits on Classical Conditioning (part 1)

• Biological constraints: Evolved biological tendencies that predispose animals’ behavior and learning, making certain behaviors easier to learn than others. • Example: Garcia and Koelling’s taste-aversion research

• Animals, including humans, seem biologically prepared to learn some associations rather than others.

• Conditioning is stronger when the CS is ecologically relevant.

• The genetic predisposition to associate a CS with an US that follows predictably and immediately is adaptive.

5/16/2019

7

Biological Limits on Classical Conditioning (part 2)

• Nature limits species’ capacity for operant conditioning.

• Biological constraints predispose organisms to learn associations that are naturally adaptive.

• Instinctive drift occurs as animals revert to biologically predisposed patterns.

Cognition and Classical Conditioning (part 1)

• Mental information that guides behavior is acquired through cognitive learning.

• Animals learn the predictability of an event (Rescorla & Wagner, 1972).

• The more predictable the association between a neutral stimulus and an unconditioned stimulus, the stronger the conditioned response.

• It’s as if the animal learns an expectancy—an awareness of how likely it is that the US will occur.

Cognition and Classical Conditioning (part 2)

• Skinner acknowledged the biological underpinnings of behavior but has been criticized for discounting the importance of cognition.

• Evidence of cognitive processes • Animal response on a fixed-interval reinforcement

schedule • Development of cognitive maps in rats (latent learning

that becomes evident only when there is an incentive to demonstrate it)

• Intrinsic motivation: A desire to perform a behavior effectively for its own sake

• Extrinsic motivation: A desire to perform a behavior to receive promised rewards or avoid threatened punishment

Cognition and Classical Conditioning (part 3)

Classical Conditioning Operant Conditioning

Biological influences Natural predispositions constrain what stimuli and responses can easily be associated.

Organisms most easily learn behaviors similar to their natural behaviors; unnatural behaviors instinctively drift back toward natural ones.

Cognitive influences Organisms develop an expectation that a CS signals the arrival of a US.

Organisms develop an expectation that a response will be reinforced or punished; they also exhibit latent learning, without reinforcement.

Learning by Observation

• Observational learning: Higher animals, especially humans, learn without direct experience by watching and imitating others.

• Albert Bandura is the pioneering researcher of observational learning • His Bobo doll experiment showed direct imitation by

children of adult behavior.

• Modeling: The process of observing and imitating a specific behavior. • Vicarious reinforcement and vicarious punishment

are experienced by watching models.

The Bobo Doll Experiment

5/16/2019

8

Mirrors and Imitation in the Brain

• Mirror neurons: Frontal lobe neurons that some scientists believe fire when a person performs certain actions or observes another doing so; provide a neural basis for everyday imitation and observational learning.

• The brain’s mirroring of another’s action may enable imitation and empathy.

• In humans, imitation is pervasive: So strong is the human predisposition to learn from watching adults that children will overimitate, copying even irrelevant adult actions.

• The brain response to observing others makes emotions contagious.

Experienced and Imagined Pain in the Brain

Applications of Observational Learning (part 1)

• Prosocial effects • Prosocial modeling of behavior can have prosocial

effects. • Behavior modeling enhances learning of communication,

sales, and customer service skills in new employees. • Modeling nonviolent, helpful behavior prompts similar

behavior in others. • Research across seven countries showed that viewing

prosocial media increased later helping behavior. • Socially responsive toddlers tend to have a strong

internalized conscience as preschoolers. • Models are most effective when they include consistent

actions and words.

Applications of Observational Learning (part 2)

• Antisocial effects • Abusive parents may have aggressive children.

• Watching TV and videos may teach children: • Bullying is an effective tool for controlling others.

• Free and easy sex doesn’t have later consequences.

• Men should be tough; women should be gentle.

• The violence-viewing effect is demonstrated when viewing media violence triggers violent behavior.

• Watching cruelty may foster indifference.