Myers’ PSYCHOLOGY

Myers’ PSYCHOLOGY

Chapter 8Learning

Learning Learning

relatively permanent change in an organism’s behavior due to experience

experience (nurture) is the key to learning

AssociationWe learn by association

Our minds naturally connect events that occur in sequence

Aristotle 2000 years ago John Locke and David Hume 200 yrs

agoAssociative Learning

learning that two events occur togethertwo stimulia response and its consequences

Association

Learning to associate two events

Event 1 Event 2

Sea snail associates splash with a tail shock

Seal learns to expect a snack for its showy antics

Classical or Pavlovian Conditioning

We learn to associate two stimuli

Two related events:

Lightning

Stimulus 1

Thunder

Stimulus 2

Result after repetition

We see lightning

Stimulus

We wince anticipatingthunder

Response

Operant Conditioning

We learn to associate a response and its consequence

Response: Pushingvending machine button

Consequence: Receiving a candy bar

BehaviorismJohn B. Watson

viewed psychology as objective sciencegenerally agreed-upon

consensus today recommended study of behavior

without reference to unobservable mental processesnot universally accepted by all

schools of thought today


Ivan Pavlov 1849-1936 Russian physician/

neurophysiologist Nobel Prize in 1904 studied digestive secretions

Pavlov’s Classic Experiment

Before Conditioning

During Conditioning After Conditioning

UCS (foodin mouth)

Neutralstimulus(tone)

Nosalivation

UCR (salivation)

Neutralstimulus(tone)

UCS (foodin mouth)

UCR(salivation)

CS(tone)

CR (salivation)


Pavlov’s device for recording salivation

Classical or Pavlovian ConditioningClassical Conditioning

organism comes to associate two stimulilightning and thundertone and food

begins with a reflex a neutral stimulus is paired with a

stimulus that evokes the reflex neutral stimulus eventually comes to

evoke the reflex


Unconditioned Stimulus (UCS) effective stimulus that unconditionally-

automatically and naturally- triggers a response

Unconditioned Response (UCR) unlearned, naturally occurring

automatic response to the unconditioned stimulussalivation when food is in the mouth


Conditioned Stimulus (CS) previously neutral stimulus that, after

association with an unconditioned stimulus, comes to trigger a conditioned response

Conditioned Response (CR) learned response to a previously neutral

conditioned stimulus

ConditioningAcquisition

the initial stage of learning, during which a response is established and gradually strengthened

in classical conditioning, the phase in which a stimulus comes to evoke a conditioned response

in operant conditioning, the strengthening of a reinforced response

ConditioningExtinction

diminishing of a CR in classical conditioning, when

a UCS does not follow a CS in operant conditioning, when

a response is no longer reinforced


Strengthof CR

Pause

Acquisition(CS+UCS)

Extinction(CS alone)

Extinction(CS alone)

Spontaneousrecovery ofCR


Spontaneous Recovery reappearance, after a rest

period, of an extinguished CRGeneralization

tendency for a stimuli similar to CS to evoke similar responses


Discrimination in classical conditioning, the ability to

distinguish between a CS and other stimuli that do not signal and UCS

in operant conditioning, responding differently to stimuli that signal a behavior will be reinforced or will not be reinforced

GeneralizationDrops of salivain 30 seconds

60

50

40

30

20

10

0Hindpaw

Pelvis Shoulder Frontpaw

Thigh Trunk Foreleg

Part of body stimulated


UCS(passionate kiss) UCR

(sexualarousal)

CS(onionbreath)

CS(onion breath) CR

(sexualarousal)

UCS(passionate Kiss) UCR

(sexualarousal)

Nausea Conditioning in Cancer Patients

UCS(drug)

UCR(nausea)

CS(waiting room)

CS(waitingroom) CR

(nausea)

UCS(drug)

UCR(nausea)

Operant ConditioningOperant Conditioning

type of learning in which behavior is strengthened if followed by reinforcement or diminished if followed by punishment

Law of Effect Thorndike’s principle that behaviors

followed by favorable consequences become more likely and behaviors followed by unfavorable consequences become less likely

Operant ConditioningOperant Behavior

complex or voluntary behaviorspush button, perform complex task

operates (acts) on environment produces consequences

Respondent Behavior occurs as an automatic response to

stimulus behavior learned through classical

conditioning

Operant ConditioningB.F. Skinner (1904-1990)

elaborated Thorndike’s Law of Effect

developed behavioral technology

Operant ChamberSkinner Box

soundproof chamber with a bar or key that an animal presses or pecks to release a food or water reward

contains a device to record responses

Operant ConditioningReinforcer

any event that strengthens the behavior it follows

Shaping conditioning procedure in which

reinforcers guide behavior toward closer approximations of a desired goal

Successive Approximations reward behaviors that increasingly

resemble desired behavior

Principles of Reinforcement

Primary Reinforcer innately reinforcing stimulus satisfies a biological need

Secondary Reinforcer conditioned reinforcer learned through association with

primary reinforcer

Schedules of ReinforcementContinuous Reinforcement

reinforcing the desired response each time it occurs

learning occurs rapidly extinction occurs rapidly

Partial Reinforcement reinforcing a response only part of the

time results in slower acquisition greater resistance to extinction

Schedules of Reinforcement

Fixed Ratio (FR) reinforces a response only after a

specified number of responses faster you respond the more rewards

you get different ratios very high rate of responding like piecework pay


Variable Ratio (VR) reinforces a response after an

unpredictable number of responses

average ratios like gambling, fishing very hard to extinguish because

of unpredictability


Fixed Interval (FI) reinforces a response only after

a specified time has elapsed response occurs more

frequently as the anticipated time for reward draws near


Variable Interval (VI) reinforces a response at

unpredictable time intervals produces slow steady responding like pop quiz


Variable Interval

Number of responses

1000

750

500

250

010 20 30 40 50 60 70

Time (minutes)

Fixed Ratio

Variable Ratio

Fixed Interval

Steady responding

Rapid respondingnear time forreinforcement

80

Punishment

Punishment aversive event that

decreases the behavior that it follows

powerful controller of unwanted behavior

Problems with Punishment

Punished behavior is not forgotten, it's suppressed- behavior returns when punishment is no longer eminent

Causes increased aggression- shows that aggression is a way to cope with problems- Explains why aggressive delinquents and abusive parents come from abusive homes

Problems with PunishmentCreates fear that can generalize to

desirable behaviors, e.g. fear of school, learned helplessness, depression

Does not necessarily guide toward desired behavior- reinforcement tells you what to do--punishment tells you what not to do- Combination of punishment and reward can be more effective than punishment alone

Punishment teaches how to avoid it

Cognition and Operant Conditioning

Cognitive Map mental representation of the layout of

one’s environment example- after exploring a maze, rats

act as if they have learned a cognitive map of it

Latent Learning learning that occurs, but is not

apparent until there is an incentive to demonstrate it

Cognition and Operant Conditioning

Overjustification Effect the effect of promising a reward

for doing what one already likes to do

the person may now see the reward, rather than intrinsic interest, as the motivation for performing the task

Latent Learning

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 2202468

101214161820222426283032Average

errors

Days

Operant vs Classical Conditioning

Extinction CR decreases when CS is Responding decreases whenrepeatedly presented alone. reinforcement stops.

Classical Conditioning

OperantConditioning

The Response Involuntary, automatic “Voluntary,” operates on environment

Acquisition Associating events; Associating response with aCS announces UCS. Consequence (reinforcer or

punisher).

Cognitive Subjects develop expectation Subjects develop expectation that processes that CS signals the arrival of a response will be reinforced or

UCS. Punished; they also exhibit latentlearning, without reinforcement

Biological Natural predispositions Organisms best learn behaviors predispositions contain what stimuli and similar to their natural behaviors;

responses can easily be unnatural behaviors instinctivelyassociated. drift back toward natural ones.

Observational Learning

Observational Learning learning by observing and imitating

othersModeling

process of observing and imitating behavior

Prosocial Behavior positive, constructive, helpful behavior opposite of antisocial behavior

Myers’ PSYCHOLOGY

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