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Chapter6:Learning
BasicTerminology
• Learning-changeinanorganism’sbehaviororthoughtasaresultofexperience
• Habitua-on-processbywhichwerespondlessstronglyoverDmetorepeatedsDmuli
• Sensi-za-on-processbywhichwerespondmorestronglyoverDme(especiallyfordangerous,irritaDngsDmuli)
IvanPetrovichPavlov
• Russianphysiologistand1904NobelPrizewinner
• DecidedtobeascienDstaQerreadingtheworksofCharlesDarwin
• MostfamousforhisworkonthedigesDonofthedog,whichincludedthefirstworkonclassicalcondiDoning
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ClassicalCondiDoning• Pavlovdescribedclassicalcondi-oning,involving:– UCSuncondiDonedsDmulus-biologicallysignificantsDmulusthatproducesautomaDcresponse
– UCRuncondiDonedresponse-automaDcresponsetoaUCSthatoccurswithoutlearning
– CScondiDonedsDmulus-iniDallyneutralsDmulus,becomesassociatedwiththeUCSthroughcondiDoning
– CRcondiDonedresponse-learnedresponse
• ByvirtueofCS-UCSpairing,theCScomestoelicittheCR,aresponsecloselyrelated,butnotidenDcal,totheUR
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Pavlov’sClassicalCondiDoningModel
ClassicalCondiDoning
• Aversivecondi-oning-classicalcondiDoningtoanunpleasantUCS– Avoidanceresponse
• ClassicalcondiDoningisadap-veinpreparingtheorganismfortheimpendingUS– PsychopathicpersonaliDes-indifferenttosignalsofthreat
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ClassicalCondiDoning
• Acquisi-on-learningphaseduringwhichaCRisestablished
• Ex-nc-on-gradualdecreaseandeliminaDonoftheCRwhentheCSispresentedrepeatedlywithouttheUCS
AcquisiDonandExDncDon
ClassicalCondiDoning
• Spontaneousrecovery-suddenreemergenceofanexDnguishedCRaQeradelay
• Phobias-intenseandirraDonalfears– SomeacquiredviaclassicalcondiDoning– Subjecttospontaneousrecoveryandrenewal
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ClassicalCondiDoning
• S-mulusgeneraliza-on-elicitaDonofaCRtosDmulithatarehighlysimilarto,butnotidenDcalto,theCS– GeneralizaDongradient-themoresimilartotheoriginalCSthenewCSis,thestrongerwillbetheCR
• S-mulusdiscrimina-on-oppositeofsDmulusgeneralizaDon;occurswhenweexhibitaCRtocertainCSs,butnotothers
GeneralizaDonGradient
ConceptCheck:
Apuffofairisblownintoarabbit’seyejustaQeramusicaltoneisplayed.AQerseveralrepeDDonsofthisprocedure,therabbitclosesitseyewhenthemusicaltoneisplayed.Whatarethe:• US• UR• NeutralSDmulus/CS• CR
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CCinDailyLife
Acquisi-onoffears:LiEleAlbert• Watson&Reyner(1920)soughttodisprovethe
Freudianviewofphobia,reflecDngdeep-seatedunconsciousconflict
• Theyrecruitedaninfant,Albert,andpairedawhiterat(CS)withaloudclangingmetalnoise(UCS)
• Fivedayslater,Albertexhibitedfearoftherat,andsimilarsDmuli,includingarabbit,dog,furrycoat,andSantaClausmask(generalizaDonofphobia)
CCinDailyLife
• LedtothecondiDoningmodelofphobias
• ClassicalcondiDoningalsooffersawaytogetridofphobia– MaryCloverJones(1924)successfullytreatedthree-year-oldPeter,whohadaphobiaofrabbits,byslowlyintroducingarabbitpairedwithcandies
– SimilarexposuretherapyissDllthemainbehavioraltreatmentforirraDonalfears
CCinDailyLife
Disgustreac-ons-inmostcases,aproductofclassicalcondiDoningbecauseCSsassociatedwithdisgusDngUCSscometoelicitdisgustthemselves– Rozin’s(1986)subjectsshowagreatreluctancetoeatapieceoffudgeshapedlikedogfeces
– SubjectsshowagreatreluctancetodrinkasucrosesoluDonlabeledpoison,evenwhentheyputthemeaninglesslabelonthere(“behersafethansorry”heurisDc)
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OperantCondiDoning
• Orinstrumentalcondi/oning-acquiringbehaviorsasaresultoftheoutcomeorconsequenceofthosebehaviors– Theorganismgetssomethingoutoftheresponseor“operates”onitsenvironment(e.g.,usingbiscuitsasatreat,atrainerteachesadogtosit)
OperantvsClassicalCondiDoning
Elicited by UCS or CSOrganism emits
response in a seemingly
voluntary fashionIndependent of what
the animal doesOrganism must make
response
Often involves autonomic nervous
system
Often involves the skeletal muscles
Classical Operant
Response
Reward
BodySystem
LawofEffect• E.L.Thorndike(1898)studiedcatsinpuzzleboxes,which
ledtothelawofeffect:Ifaresponse,inthepresenceofasDmulus,isfollowedbyasaDsfyingstateofaffairs,thebondbetweensDmulusandresponsewillbestrengthened
– AccordingtoThorndikeandothers,learninginvolvesanassociaDonbetweenasDmulusandresponse(S-R),withtherewardstampinginthisconnecDon
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Thorndike’sPuzzleBox
B.F.Skinner
• FolloweduponWatsonandThorndike’sworkonbehavior
• NexttoFreud,probablythemostinfluenDalpsychologist
B.F.SkinnerandReinforcement
• SkinnerdevelopedahighlyefficientcondiDoningchamber(Skinnerbox)thatallowsforcondiDoningandautomatedbehaviormeasurement– Typicallycontainsbarthatdeliversfoodwhenpressed,fooddispenser,andlightthatsignalswhenrewardisforthcoming
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RatinSkinnerBoxandElectronicDeviceforRecordingtheRat’sBehavior
TerminologyinOC• Posi-vereinforcement-pleasantsDmulusisgiventoincreasetheprobabilityofaresponse– E.g.,Getacellphoneforgoodgrades
• Nega-vereinforcement-unpleasantsDmulusisremovedtoincreasetheprobabilityofaresponse– E.g.,Aidan’smother’snaggingstopswhenhepicksuphisroom
• Punishment-unpleasantsDmulusisgiven,orpleasantsDmulusistakenaway,todecreasetheprobabilityofaresponse– E.g.,cellphonetakenawayforbreakingcurfew
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PunishmenttendstobeineffecDve
• Ittellstheorganismwhatnottodo,ratherthanwhattodo
• Createsanxietythatcaninterferewithfuturelearning
• Encouragessubversivebehavior(sneakiness)
• Providesamodelforaggressivebehavior– Physicalpunishmentisassociatedwithaggressioninadulthood
PrinciplesofReinforcement• Par-alreinforcement-behaviorsthatwereinforceonlyoccasionallyareslowertoexDnguishthanthosewereinforceconDnuously
• Schedulesofreinforcement-pahernofreinforcingabehavior– FixedRaDo-aQerregularnumberofresponses– VariableRaDo-aQerspecificnumberofresponses,onaverage
– FixedInterval-aQerspecificamountofDme– VariableInterval-aQeranaverageDmeinterval
FourMajorReinforcementSchedulesandTypicalResponsePaherns
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CondiDoningTerminology
• Discriminants-mulus(Sd)-sDmulusassociatedwiththepresenceofreinforcement– (e.g.,whistlefordog,getstreatwhenapproaches)
• Acquisi-on,ex-nc-on,spontaneousrecovery,s-mulusgeneraliza-on,ands-mulusdiscrimina-onareconceptscommontobothclassicalandoperantcondiDoning
ApplicaDonsofOC
• Shapingbysuccessivereinforcement-reinforcingbehaviorsthataren’tquitethetargetbehaviorbutthatareprogressivelycloserversionsofit
• Chaining-linkinganumberofinterrelatedbehaviorstoformalongerseries
• Premackprinciple-alessfrequentlyperformedbehaviorcanbeincreasedbyreinforcingitwithamorefrequentbehavior– Grandma’srule-vegetablesbeforedessert
ApplicaDonsofOC• Supers--ousbehavior-behaviorlinkedtoreinforcementbysheercoincidence(e.g.,luckycharmeffect)– Pigeons,athletes,etc.
• Tokeneconomies-mentalhospitalstaffcanreinforcepaDentswhobehaveinadesiredfashionusingtokens,chips,points,orothersecondaryreinforcers– Secondaryreinforcers-neutralobjectsthatpaDentscanlatertradeinfor…
– Primaryreinforcers-itemsoroutcomesthatarenaturallypleasurable,suchasafavoritefoodordrink
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RadicalBehaviorism&CogniDvePsychology
• Skinnerwasaradicalbehaviorist:thinking,emoDon,andobservablebehaviorarealldictatedbyoperantandclassicalcondiDoning;viewedcogniDvepsychologyasapseudoscience
• CogniDvelearningtheoristsfocusonhowtheorganisminterpretsthesDmulusbeforegeneraDngaresponse– TheycontendthatbehaviorisnotautomaDcorinflexible,rather,classicalandoperantcondiDonedresponsesusuallydependonthinking
OtherFormsofLearning
• Latentlearning-learningthatisn’tdirectlyobservable;welearnmanythingswithoutshowingthem– Emphasizesthedifferencebetweencompetence(whatweknow)andperformance(showingwhatweknow)– Challengetoradicalbehaviorism,impliesreinforcementisn’tnecessary
Tolman&HonzikMazeTrials:LearningAllAlong…
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SocialCogniDveLearning
• Observa-onallearning-learningbywatchingothers(models),withoutinstrucDonorreinforcement– Brainbasis?Perhapsmirrorneurons– Aggressivebehavior:Bandura(1963)hadchildrenwatchanadultignoringorpunchingaBobodollandshouDngthingslike“Kickhim”
– ChildrenwhowatchedtheaggressiveadultmodelwereaggressivetotheBobodolllater