Sarah Grison • Todd Heatherton • Michael Gazzaniga...

Chapter 6

Learning

© 2014 W. W. Norton & Company, Inc.

Sarah Grison • Todd Heatherton • Michael Gazzaniga

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


• 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


• Non-associative learning: information

about one external stimulus (e.g., a sight,

smell, sound)


• 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


• Associative learning

– Understanding how two or more pieces of

information are related


• 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


• 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


Through Classical Conditioning, We Learn 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



• 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)



• 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)



• Step 2: clicking metronome is neutral

stimulus

– Neutral stimulus: anything seen or heard;

must not associate with the unconditioned

response



• Step 3 (conditioning trials): start of

learning

– Dog begins to associate US (food) and

neutral stimulus (metronome)



• 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



• 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


• 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


• Extinction

– Extinction: A process in which the

conditioned response is weakened when the

conditioned stimulus is repeated without the

unconditioned stimulus


Learning Varies in


• 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

Learning Varies in


• 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


• 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


Generalization, Discrimination, and Second-Order Conditioning

Learning Varies in


• 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


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


The Case of Little Albert


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


• 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

Section 6.3

How Do We Learn by Operant

Conditioning?


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


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


Learning Varies in


• Shaping

– Shaping: operant-conditioning technique;

reinforce behaviors increasingly similar to

desired behavior


Shaping

Learning Varies in


• 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


• 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



• Positive and negative reinforcement

– Both positive and negative reinforcement

increase likelihood of a given behavior


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



• Positive and negative punishment

– Both positive and negative punishment

reduce likelihood that behavior will be

repeated



• 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




• 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




– 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




– Fixed interval schedule (FI): Reinforcing the

occurrence of a particular behavior after a

predetermined amount of time since the last

reward

– Example: paycheck




– 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




– 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




– Variable ratio schedule (VR): Reinforcing a

particular behavior after the behavior has

occurred an unpredictable and varying

number of times

– Example: slot machine


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


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


Parental Punishment Is Ineffective


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


• Behaviorists believed conditioning

principles explained all behavior. In reality,

reinforcement explains only a certain

amount of human behavior



• 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 constrains reinforcement

– Some animal behaviors hardwired

– Difficult to learn behaviors counter to

evolutionary adaptation

– Conditioning most effective when matched to

animal’s biological predispositions


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?


Watching Others?

• Behaviors we learn by watching others

– Mechanical skills, social etiquette, situational

anxiety, attitudes about politics and religion

• Three ways we learn by watching

1. 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


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


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


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


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

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