Assignment #2Deadline changed to JUNE 4th

Will mostly focus on Ch 7Talk about that after the midterm on Monday

Topics will be announced on Monday

Operant Punishment

Response Rate:Increases Decreases

Rem

oved

Pre

sen t

ed

Res

pons

e C

ause

s S

tim

ulus

to B

e:

Positive Reinforcement

Negative Reinforcement

Positive Punishment

Negative Punishment

Lever press --> Food

Lever press --> Shock off

Lever press --> Shock

Lever press --> Food removed

ExamplesPositive

Aversive stimulus is ADDEDSpanking, shock

NegativeAppetitive stimulus is REMOVEDTime-outs, grounding, no dessert, food taken

away

Fines??

ContingencyCorrelation between behaviour & outcomeStrong contingency --> better learningRandom contingency --> no learningBoth reinforcement and punishment

ContiguityTime between behaviour & outcome

Shorter = better learningMore important for punishment

Distraction more likely in punishment than reinforcement

Common violations

Punisher CharacteristicsQualitative differences in punishers

Species & individual differencesIntensity of punisherIntroductory level of punishment

Similar (but opposite) to learned helplessness

Reinforcement of punished behaviourHow rewarding is the behaviour itself?Related to deprivation levelsAlternative sources of reinforcement

Real applications

Disruption TheoryIncompatible behaviourPunished behaviour is suppressedProblems

Intensity of punisherContingency

Two-Process Theory (revisited)Same theory we talked about for

escape/avoidanceClassical & OperantSame problems as before

Proximity to punished stimulus

One-Process Theory (revisited)Symmetry with reinforcementPremack principle

Low-probability behaviour punishes high-probability behaviour

BenefitsShort-term effectiveness

ReinforcingPowerful & Fast

Rapid and substantial reduction in behaviourBeneficial?

ProblemsApplication of punishersPunishment generally not used correctlyTolerance

Start with strong punisherGradually reduce

General reluctance to administer

Possible Consequences of PunishmentEscapeAggression

At punisher, self, otherApathy

General suppression of other behavioursAbuse

Permanent damageImitation

Response PreventionMake it impossible to do punishable

behaviourSubject can circumvent thisBest with younger children

ExtinctionIdentify reinforcer of behaviourWithhold reinforcer … extinction of

behaviourOften difficult to identify the reinforcerExtinction bursts problematicNot a rapid solution

Differential ReinforcementFour Types:

DRL: Differential reinforcement of low responses

DRO: Differential reinforcement of zero responses

DRI: Differential reinforcement of incompatible behaviour

DRA: Differential reinforcement of alternative behaviour

DRLDifferential reinforcement of low responsesOnly reinforce behaviour when response

occurs at low frequencyGood for reducing RATE of behavioure.g. pigeon pecking at key light

Reinforce ONLY if at least 2 seconds in between pecks

e.g. too many compliments

DRODifferential reinforcement of zero responsesor DR of Omission of behaviourReinforcement contingent on not performing

behaviour at all (in some time period)Very similar to DRL, but goal is to eliminate

behaviour

DRIDifferential reinforcement of incompatible

behaviourReinforce behaviour incompatible with

undesired responsee.g. riding bike vs playing video game

DRADifferential reinforcement of alternative

behaviourReinforcer gained from undesired behaviour

now only available when some alternative behaviour done

Alternate source of reinforcementUsed more in cases where DRI is not an

option

Noncontingent ReinforcementProvide desired reinforcer on regular basis

regardless of what is being doneNo correlation between response and outcomeMay work because subject gets reinforcer for

“free”Problems if reinforcer comes after some other

undesired behaviour (new acquisition)

Chivalrous Charlie example (p. 87 of workbook)

Negative PunishmentRemoval of pleasant stimulusTime-outPopular in human behaviour modification

Other Techniques for Behavioural DecelerationOvercorrection

Repetitions of alternate, desired behaviour Restitution Positive practice

Technically, punishmentStimulus satiation

Latent LearningMotivationLearning behaviourPerforming behaviour

day 11

Ave

rage

Err

ors

Days

No food

Food reward

No food reward until day 11

Start BoxGoal