chapter 6 learning © 2014 w. w. norton & company, inc. sarah grison todd heatherton michael...

Chapter 6Learning

© 2014 W. W. Norton & Company, Inc.

Sarah Grison • Todd Heatherton • Michael Gazzaniga

Psychology in Your Life

Psychology in Your Life

FIRST EDITION

Section 6.1

How Do the Parts of Our Brains Function?

6.1 What Are the Three Ways We Learn?

• Learning: A change in behavior, resulting from experience– Central to almost all areas of human

existence

We Learn From Experience

• Behaviorism: a formal learning theory from the early twentieth century– John Watson: focused on environment and

associated effects as key determinants of learning

– B. F. Skinner: designed animal experiments to discover basic rules of learning

We Learn From Experience

• Critical for survival

• Adapt behaviors for a particular environment– Which sounds indicate potential danger?– What foods are dangerous?– When is it safe to sleep?

We Learn in Three Ways

1. Non-associative learning

2. Associative learning

3. By watching others

We Learn in Three Ways

• Non-associative learning– Information about one external stimulus (e.g.,

a sight, smell, sound)– Habituation: A decrease in behavioral

response after lengthy or repeated exposure to a stimulus

– Especially if the stimulus is neither harmful nor rewarding

• See Figure 6.2a next slide

We Learn in Three Ways

• Non-associative learning: information about one external stimulus (e.g., a sight, smell, sound)

We Learn in Three Ways

We Learn in Three Ways

• Non-associative learning– Sensitization: An increase in behavioral

response after lengthy or repeated exposure to a stimulus

– Heightened preparation in a situation with potential harm or reward

• See Figure 6.2b next slide

We Learn in Three Ways

We Learn in Three Ways

• Associative learning– Understanding how two or more pieces of

information are related

We Learn in Three Ways

• Associative learning

• Classical conditioning: learn that two stimuli go together– Example: music from scary movies elicits

anxiousness when heard

• Operant conditioning: learn that a behavior leads to a particular outcome– Example: studying leads to better grades

We Learn in Three Ways

• Learning by watching others– Observational learning – Modeling– Vicarious conditioning

The Brain Changes During Learning

• Long-term potentiation (LTP)– The strengthening of synaptic connections

between neurons– Recall that “cells that fire together, wire

together”– Exposure to environmental events causes

changes in the brain to allow learning

Section 6.2

How Do We Learn by Classical Conditioning?

6.2 How Do We Learn by Classical Conditioning?

• Familiar example: association between scary music in movies and bad things happening to characters

Through Classical Conditioning, We Learn That Stimuli Are Related• Pavlov: Nobel Prize in 1904 for research

on the digestive system

• Observed dogs began to salivate as soon as they saw bowls of food– Salivating at the sight of a bowl is not

automatic– Behavior acquired through learning by

association

• See Figure 6.3b next slide

Through Classical Conditioning, We Learn Stimuli Are Related

Through Classical Conditioning, We Learn That Stimuli Are Related

• Classical conditioning– A type of learned response in which a neutral

object comes to elicit a response when it is associated with a stimulus that already produces a response

Through Classical Conditioning, We Learn That Stimuli Are Related• Pavlov’s Experiments Reveal the

Four Steps in Classical Conditioning :1. Present unconditioned stimulus: evokes

unlearned response

2. Present neutral stimulus: no response

3. Pair stimuli from Steps 1 and 2: learned response (conditioning trials)

4. Neutral stimulus alone will trigger learned response (critical trials)

Through Classical Conditioning, We Learn That Stimuli Are Related• Pavlov’s Experiments Reveal the

Four Steps in Classical Conditioning– Step 1: presenting food causes salivary reflex– Unconditioned stimulus (US): A stimulus

that elicits a response that is innate and does not require any prior learning (Food)

– Unconditioned response (UR): A response that does not have to be learned, such as a reflex (Salivation)

Through Classical Conditioning, We Learn That Stimuli Are Related• Step 2: clicking metronome is neutral

stimulus– Neutral stimulus: anything seen or heard;

must not associate with the unconditioned response

Through Classical Conditioning, We Learn That Stimuli Are Related• Step 3 (conditioning trials): start of

learning– Dog begins to associate US (food) and

neutral stimulus (metronome)

Through Classical Conditioning, We Learn That Stimuli Are Related• Step 4 (critical trials): Association learned

– Metronome alone, without food, makes dog salivate

• See Figure 6.3 next slide

Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning

Through Classical Conditioning, We Learn That Stimuli Are Related• Conditioned stimulus (CS): A stimulus

that elicits a response only after learning has taken place

• Conditioned response (CR): A response to a conditioned stimulus; a response that has been learned

• See Scientific Thinking: Pavlov’s Experiments Reveal Learning by Classical Conditioning next slide

Learning Varies in Classical Conditioning

• Animals adapt via conditioning– Learning to predict outcomes leads to new

adaptive behaviors

Learning Varies in Classical Conditioning

• Acquisition– Acquisition: The gradual formation of an

association between conditioned and unconditioned stimuli.

– Strongest conditioning occurs when CS is presented slightly before US

• See Figure 6.5a next slide

Acquisition, Extinction, and Spontaneous Recovery

Learning Varies in Classical Conditioning

• Extinction – Extinction: A process in which the

conditioned response is weakened when the conditioned stimulus is repeated without the unconditioned stimulus

• See Figure 6.5b next slide

Acquisition, Extinction, and Spontaneous Recovery

Learning Varies in Classical Conditioning

• Spontaneous recovery– Spontaneous recovery: A process in which a

previously extinguished response reemerges after the conditioned stimulus is presented again

– Can occur after only one pairing following extinction

– Response will weaken if CS-US pairings do not continue

• See Figures 6.5c, 6.5d next slide

Acquisition, Extinction, and Spontaneous Recovery

Learning Varies in Classical Conditioning

• Generalization, discrimination, and second-order conditioning– Stimulus generalization: Learning that

occurs when stimuli that are similar but not identical to the conditioned stimulus produce the conditioned response

– Animals respond to variations in CS

Learning Varies in Classical Conditioning

• Generalization, discrimination, and second-order conditioning– Stimulus discrimination: A differentiation

between two similar stimuli when only one of them is consistently associated with the unconditioned stimulus

• See Figure 6.6 next slide

Generalization, Discrimination, and Second-Order Conditioning

Learning Varies in Classical Conditioning

• Generalization, Discrimination, and Second-Order Conditioning– Second-order conditioning: second CS

becomes associated with first CS; elicits CR when presented alone

– Neither US nor original CS present– Example: pairing black square (second CS)

with metronome (first CS) so black square produces salivation (CR) on its own

We Learn Fear Responses Through Classical Conditioning

• Phobia– Acquired fear that is very strong in

comparison to threat

We Learn Fear Responses Through Classical Conditioning

• The Case of Little Albert

• Classical conditioning demonstrated in phobias:– Watson showed “Little Albert” various neutral

objects (e.g., white rat, rabbit, dog, monkey, white wool)

– Paired rat (CS) and loud clanging (US) until rat alone produced fear (CR)

– Fear generalized to all similar stimuli

• See Figure 6.7 next slide

The Case of Little Albert

We Learn Fear Responses Through Classical Conditioning

• Counterconditioning– Counterconditioning: exposing subject to

phobia during an enjoyable task– Systematic desensitization: exposure to

feared stimulus while relaxing

– CS -> CR1 (fear) connection replaced with CS -> CR2 (relaxation) connection

Adaptation and Cognition Influence Classical Conditioning

• Pavlov’s belief: Any two events presented together would produce learned association

• By 1960s, data suggested that some conditioned stimuli more likely to produce learning

Adaptation and Cognition Influence Classical Conditioning

• Evolutionary Influences– Certain pairings more likely to be associated– Conditioned taste aversions: easy to produce

with smell or taste cues– Auditory and visual stimuli: value for signaling

danger

• See figure 6.8 next slide

Adaptation and Cognition InfluenceClassical Conditioning

Adaptation and Cognition Influence Classical Conditioning

• Cognitive Influences– Through classical conditioning, animals

predict events– Easier when CS before US rather than after

US– Easier when CS is more unexpected or

surprising

• See figure 6.9 next slide

Section 6.3

How Do We Learn by Operant Conditioning?

6.3 How Do We Learn by Operant Conditioning?

• Operant conditioning– A learning process in which the

consequences of an action determine the likelihood that the action will be performed in the future

Animals Learn through the Outcomes

of Their Actions• Thorndike’s Experiments Reveal the

Effects of Action– Thorndike’s puzzle box: challenged food-

deprived animals to find escape– Trap door would open if animal performed

specific action– Animal quickly learned to repeat behavior to

free itself and reach the food

• See Figure 6.10 next slide

Thorndike’s Experiments Reveal the Effects of Action

Animals Learn through the Outcomes

of Their Actions• Thorndike’s general theory of learning

– Law of effect: any behavior leading to a “satisfying state of affairs” likely to be repeated

– Any behavior leading to an “annoying state of affairs” less likely to reoccur

Learning Varies in Operant Conditioning

• B. F. Skinner’s learning theory based on the law of effect– Animals operate on environments to produce

effects– Reinforcer: stimulus occurs after response and

increases likelihood of response reoccurring– Consequences determine likelihood of

behavior in future

• See figure 6.11 next slide

Learning Varies in Operant Conditioning

• Shaping– Shaping: operant-conditioning technique;

reinforce behaviors increasingly similar to desired behavior

• See Figure 6.12 next slide

Shaping

Learning Varies in Operant Conditioning

• Reinforcers can be conditioned– Reinforcers that are necessary for survival,

such as food or water, are called primary reinforcers

– Events or objects that serve as reinforcers but do not satisfy biological needs are called secondary reinforcers

Learning Varies in Operant Conditioning

• Reinforcer potency – Premack principle: more valued activity can

reinforce performance of less valued activity– Example: “Eat your spinach and then you’ll

get dessert”

Reinforcement and Punishment Influence Operant Conditioning

• Reinforcement and punishment have opposite effects on behavior– Reinforcement: behavior more likely to be

repeated– Punishment: behavior less likely to occur

again

Reinforcement and Punishment Influence Operant Conditioning

• Positive and negative reinforcement– Both positive and negative reinforcement

increase likelihood of a given behavior

Reinforcement and Punishment Influence Operant Conditioning

• Positive and negative reinforcement– Positive reinforcement: The addition of a

stimulus to increase the probability that a behavior will be repeated

– Example: feeding a rat after it has pressed a lever

– Negative reinforcement: The removal of a stimulus to increase the probability that a behavior will be repeated

– Example: taking a pill to get rid of a headache

Reinforcement and Punishment Influence Operant Conditioning

• Positive and negative punishment– Both positive and negative punishment

reduce likelihood that behavior will be repeated

Reinforcement and Punishment Influence Operant Conditioning

• Positive and Negative Reinforcement– Positive punishment: The addition of a

stimulus to decrease the probability that a behavior will recur

– Example: electrical shock, speeding ticket– Negative punishment: The removal of a

stimulus to decrease the probability that a behavior will recur

– Example: loss of food, loss of privileges

• See figure 6.14 next slide

Reinforcement and Punishment Influence Operant Conditioning

• Schedules of partial reinforcement– Continuous reinforcement: behavior

reinforced each time it occurs– Fast learning, uncommon in real world– Partial reinforcement: behavior is occasionally

reinforced – More common in real world

Reinforcement and Punishment Influence Operant Conditioning

• Schedules of partial reinforcement– How reinforcement given by how

consistently given = four common schedules

1. Fixed schedule: predictable basis

2. Variable schedule: unpredictable basis

3. Interval schedule: based on passage of time

4. Ratio schedule: based on number of responses

Reinforcement and Punishment Influence Operant Conditioning

• Schedules of partial reinforcement– Fixed interval schedule (FI): Reinforcing the

occurrence of a particular behavior after a predetermined amount of time since the last reward

– Example: paycheck

Reinforcement and Punishment Influence Operant Conditioning

• Schedules of partial reinforcement– Variable interval schedule (VI): Reinforcing

the occurrence of a particular behavior after an unpredictable and varying amount of time since the last reward

– Example: pop quiz– More consistent response rates than fixed

interval

Reinforcement and Punishment Influence Operant Conditioning

• Schedules of partial reinforcement– Fixed ratio schedule (FR): Reinforcing a

particular behavior after that behavior has occurred a predetermined number of times

– Example: paid by the completed task– Often yields better response rates than fixed

interval

Reinforcement and Punishment Influence Operant Conditioning

• Schedules of partial reinforcement– Variable ratio schedule (VR): Reinforcing a

particular behavior after the behavior has occurred an unpredictable and varying number of times

– Example: slot machine

• See Figure 6.15 next slide

Schedules of Partial Reinforcement

Reinforcement and Punishment Influence Operant Conditioning

• Schedules of partial reinforcement– Partial-reinforcement extinction effect:

behavior lasts longer under partial reinforcement than under continuous reinforcement

• To condition behavior to persist:– Use continuous reinforcement initially– Slowly change to partial reinforcement

Operant Conditioning Affects Our Lives

• Parental Punishment Is Ineffective

• To be effective, punishment must be– Reasonable– Unpleasant– Applied immediately– Clearly connected to the unwanted behavior

Operant Conditioning Affects Our Lives

• Parental Punishment Is Ineffective

• Punishment can cause confusion– Wrongly applied after desirable behavior– Leads to negative emotions (e.g., fear, anxiety)– Fails to offset reinforcing aspects of the

undesired behavior

• Reinforcement teaches desirable behavior

• See Figure 6.16 next slide

Parental Punishment Is Ineffective

Operant Conditioning Affects Our Lives

• Behavior modification– Behavior modification: operant conditioning

replaces unwanted behaviors with desirable behaviors

– Token economies: opportunity to earn tokens (secondary reinforcers) for completing tasks and lose tokens for behaving badly

– Tokens later traded for objects or privileges– Gives participants sense of control

Biology and Cognition Influence Operant Conditioning

• Behaviorists believed conditioning principles explained all behavior. In reality, reinforcement explains only a certain amount of human behavior

Biology and Cognition Influence Operant Conditioning

• Dopamine activity affects reinforcement– Dopamine has a biological influence on

reinforcing value– Drugs that block dopamine’s effects disrupt

operant conditioning– Drugs that enhance dopamine activation

increase reinforcing value of stimuli

Biology and Cognition Influence Operant Conditioning

• Biology constrains reinforcement– Some animal behaviors hardwired– Difficult to learn behaviors counter to

evolutionary adaptation– Conditioning most effective when matched to

animal’s biological predispositions

Biology and Cognition Influence Operant Conditioning

• Learning without reinforcement– Tolman argued that reinforcement impacts

performance more than knowledge acquisition– Ran rats through complex mazes to obtain

food– Cognitive map: A visuospatial mental

representation of an environment

Biology and Cognition Influence Operant Conditioning

• Learning without reinforcement

• In Tolman’s study three groups of rats traveled maze

– Group 1: No reinforcement

– Group 2: Reinforcement every trial

– Group 3: Reinforcement only after first 10 trials

• See Figure 6.19 next slide

Learning Without Reinforcement

Biology and Cognition Influence Operant Conditioning

• Learning without reinforcement– Latent learning: Learning that takes place in

the absence of reinforcement– Group 1: Slow, many wrong turns– Group 2: Faster, fewer errors each trial– Group 3: Before reinforcement, similar to

Group 1. After reinforcement, better than Group 2

Biology and Cognition Influence Operant Conditioning

• Learning without reinforcement– Insight learning: A sudden understanding of

how to solve a problem after a period of either inaction or thinking about the problem

Section 6.4

How Do We Learn by Watching Others?

6.4 How Do We Learn by Watching Others?

• Behaviors we learn by watching others– Mechanical skills, social etiquette, situational

anxiety, attitudes about politics and religion

• Three ways we learn by watching1. Observational learning

2. Modeling

3. Vicarious conditioning

Three Ways We Learn through Watching

1. Observational learning: The acquisition or modification of a behavior after exposure to at least one performance of that behavior– Examples: foods safe to eat, objects and

situations to fear– Powerful adaptive tool

• See Figure 6.20 next slide

Three Ways We Learn through Watching

Three Ways We Learn through Watching

• Bandura’s research reveals learning through observation– Observation of aggression: Bandura’s Bobo

doll study– Group 1: watched film of adult playing quietly

with Bobo, an inflatable doll– Group 2: watched film of adult attacking Bobo– Viewers of aggression were more than twice

as likely to play aggressively

Three Ways We Learn through Watching

• Learning through modeling

• Modeling: The imitation of behavior through observational learning– More likely to imitate actions of attractive,

high-status models similar to ourselves

• See Figure 6.22 next slide

Learning Through Modeling

Three Ways We Learn through Watching

• Learning through vicarious conditioning

• 3. Vicarious conditioning: Learning the consequences of an action by watching others being rewarded or punished for performing the action– Rewarded behavior more imitated– Punished behavior less imitated

• See Figure 6.23 next slide

Learning Through Vicarious Conditioning

Watching Others Results in Cultural Transmission

• Meme: shared piece of cultural knowledge– Similar to genes, selectively passed across

generations, can spread much faster– Animals also show this kind of knowledge

sharing

• See Figure 6.24 next slide

Watching Others Results in Cultural Transmission

Biology Influences Observational Learning

• Mirror neurons– Fire in your brain and other person’s brain

every time you watch them engaging in an action

– Does not always lead to imitation– Scientists are still debating mirror neurons’

function