Lecture 6- Learning. PYB100 SAMPLE Revision

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1 PYB100 SAMPLE Revisin Lecture 6- Learning Milestnes t cnsider in histrical cntext 1920s Behaviurism, classic cnditining and perant cnditining 1960s and 70s cgnitive psychlgy and evlutinary psych Adapt t envirnment and stimuli Define learning Central issue in behaviurist perspective Learning is any enduring change in the way an rganism respnds, based n its experiences Change r adaptin in behaviur Endures ver time Necessary fr survival in a changing envirnment Key issue: learning cannt be bserved directly, it is inferred frm behaviur that is bserved Mdify behaviur fr next times situatin happens cntext Apply knwledge frm ne situatin t anther Classical cnditining- Ivan Pavlv ( ) Assciating a neutral stimulus with a stimulus that leads t reflexive respnse In classical cnditining, all respnses are reflexes r autnmic respnses- invluntary Eg. Classical cnditined feelings are nt altered by lgical reasning Eg. With dgs: Salivating, breathing, blinking, stimuli naturally ccurs Neutral stimulus turned int cnditin stimulus Pair stimuli which are assciated- a behaviur fllws Classic cnditining f emtinal respnses Emtinal respnses can be learned eg. Little Albert experiment

2 PYB100 SAMPLE Revisin If a respnse is cnditined t ne stimulus, the rganism may als respnd t a similar stimulus (generalisatin) but nt t a dissimilar stimulus (discriminatin) Generalisatin- specific stimulus applying t anther stimulus Classic cnditining- advertisement Prduct assciated with situatin, image that is attractive: intended emtinal respnse Principles f classical cnditining Acquisitin Extinctin- weakening f cnditined respnse when the cnditined stimulus is presented withut the uncnditined stimulus Nt an unlearning, it is a learned inhibitin f respnding Imprtant implicatins fr treatment f phbias Spntaneus recvery The re-emergence f a previusly extinguished cnditined respnse Bilgical cnstraints n classical cnditining Bilgical preparedness- sme stimuli and respnses are mre likely t be cnditined than thers Operant cnditining Learning f a new assciatin between behaviur and its cnsequences It is learning thrugh reinfrcement and punishment Behaviur (respnse) is vluntary and emitted nt elicited Behaviur is mdified accrding t its cnsequences Behaviur mre likely/less likely t ccur due t psitive/negative reinfrcement Thrndike law f effect Behaviur is cntrlled by its cnsequences Behaviurs that result in pleasant cnsequences- reinfrcement- will be mre likely in the future Behaviurs that result in unpleasant cnsequences- will be less likely in the future Skinner Systematic investigatin f Thrndike s ideas All animal behaviur is learned Design envirnments that shape the behaviur Operant vs classical cnditining Classic: what happens befre a behaviur is mst imprtant fr learning In perant: cnsequences r what happens after a behaviur is mst imprtant fr learning Behaviurs are called perant Operant cnditining = cnditining these perants t ccur mre r less frequently Punishment/reinfrcement psitive/negative Psitive reinfrcement- chclate, gd grades Negative reinfrcement- remving nise, remves unpleasant stimulus Psitive punishment- spraying a cat with water, shuting at a child Negative punishment- lsing licence

3 PYB100 SAMPLE Revisin Limitatins f punishment Demnstrates what behaviur is wrng, but desn t shw what t d instead Physical punishments are wrng Can lead t imitatin f punisher, aggressin Reduces self-esteem, damages interpersnal relatins Increases use f punishment in the future Alternatives t psitive punishment Extinctin- planned ignring Respnse cst- quiet time, time ut, withdrawal f privileges Principles/characteristics f perant cnditining Immediacy Extinctin Shaping and changing- reinfrcing behaviurs that are mre similar t desired behaviur Reinfrcement schedules- intermittent reinfrcement Generalisatin and discriminatin Escape learning and avidance learning Characteristics f the learner Bilgical preparedness Individual differences Cgnitive-scial thery Cgnitive revlutin in psychlgy in 1960s Behaviurism and cgnitive and scial learning Edward Tlman Cgnitive maps- mental representatins and images Latent learning- learning that has ccurred but is nt manifest in behaviur Albert Bandura Observatinal learning- learning by bserving the behaviur f thers (mdels) Imitatin and mdelling Vicarius reinfrcement Cgnitin and learning

4 PYB100 SAMPLE Revisin Cgnitive-scial thery argues that we frm expectancies abut the cnsequence f ur behaviurs Lcus f cntrl- the expectancy f whether r nt fate determines utcmes Internal: believing that their actins determine their fate (utcmes are determined by ne s behaviur, hard wrk, attitudes and decisins) External: believe their lives are gverned by frces ut f cntrl (utcmes are independent f ne s behaviur, determined by external events, frces) Learned helplessness Expectancy that ne cannt escape aversive events Ethical issues f dg experiment Learned helplessness is central t human depressin Chapter 6- summary Learning Any enduring change in the way an rganism respnds based n its experiences Learning theries assume that experience shapes behaviur, that learning is adaptive and that uncvering laws f learning requires systematic experimentatin Classical Cnditining Refers t learning in which an envirnmental stimulus prduces a respnse in an rganism- an innate reflect is called an uncnditined reflex, the stimulus that prduces the respnse in an uncnditined reflex is called an uncnditined stimulus r UCS A cnditined respnse CR is a respnse that has been learned, a cnditined stimulus CS is a stimulus that thrugh learning, has cme t evke a cnditined respnse Once an rganism has learned t prduce a CR, it may respnd t stimuli that resemble the CS with a similar respnse- stimulus generalisatin Stimulus discriminatin is the learned tendency t respnd t a very restricted range f stimuli r nly the ne used in training Extinctin in classical cnditining: CR is weakened by presence f CS withut the USC, respnse is extinguished Factrs that influence Classical Cnditining include the inter-stimulus interval- time between presentatin f CS and UDC, the individuals learning histry and prepared learning Operant cnditining Thrndike s law f effect states that an animal s tendency t prduce a behaviur depends n that behaviurs effect n the envirnment Operant cnditining- learning t perate n the envirnment t prduce a cnsequence, perants are behaviurs that are emitted rather than elicited by the envirnment A cnsequence is said t lea t reinfrcement if it increases the prbability a respnse will recur A reinfrcer is an envirnmental cnsequence that ccurs after an rganism has prduced a respnse, makes that respnse mre likely t ccur

5 PYB100 SAMPLE Revisin Psitive reinfrcement prcess whereby presentatin f a stimulus (reward) after a behaviur makes it mre likely t ccur again Psitive reinfrcer- envirnmental cnsequence that strengthens the prbability a respnse will ccur Negative reinfrcement is the prcess whereby a terminatin f an aversive stimulus makes a behaviur mre likely t ccur Negative reinfrcers- are aversive r unpleasant stimuli that strengthen a behaviur by their remval Presentatin f a psitive reinfrcer rewards a respnse, the remval f a negative reinfrcer rewards a respnse Reinfrcement increases the prbability that a respnse will ccur- punishment decreases the prbability f a respnse Expsure t an aversive event fllwing a behaviur (psitive punishment) Lsing r failing t btain reinfrcement previusly assciated with behaviur (negative punishment) Punishment is cmmnplace in human affairs but is frequently applied in ways that render it ineffective Extinctin in perant cnditining- ccurs if enugh cnditining trials pass in which the perant is nt fllwed by its previusly learned envirnment cnsequence Schedules f reinfrcement Cntinuus: the envirnmental respnse ccurs the same time an animal emits a behaviur Intermittent- des nt ccur every time the rganism emits a respnse Fixed-rati schedule f reinfrcement- rganism receives reinfrcement at a fixed rate accrding t the number f respnses emitted, receives reinfrcement after fixed amunt f time Variable-rati- receives reward fr sme percentage f respnses, number f respnses required is unpredictable, amunt f time befre receiving reinfrcement is unknwn Discriminative stimuli- stimuli that signal t an rganism that particular cntingencies f reinfrcement are in effect Behaviural cntext - ccurs in the cntext f the ther envirnmental cntingences (eg. Impact f btaining ne reinfrcer n the prbability f btaining anther) and brader scial and cultural prcesses Characteristics f learner als influence cnditining, such as prir behaviurs in the animal s repertire, enduring characteristics f learning and species-specific behaviur Operant and classical cnditining share: extinctin, prepared learning, discriminatin, generalisatin and the pssibility f maladaptive assciatins Operant cnditining usually applies t vluntary behaviur It can als be used in techniques such as bifeedback t alter autnmic respnses which are usually the dmain f classical cnditining Cgnitive-scial thery

6 PYB100 SAMPLE Revisin Incrprates cncepts f cnditining frm behaviurism but adds tw additinal features: a fcus n cnditining and scial learning Organisms frm cgnitive maps r mental images f their envirnment and these were respnsible fr latent learning- learning that has ccurred but is nt currently manifest in behaviur Prpses expectatins r expectancies f the cnsequences f behaviur are what render behaviurs mre r less likely t ccur Lcus f cntrl- generalised expectancies peple hld abut whether r nt their behaviur will bring ut the utcmes they prefer Learned helplessness- expectancy that ne cannt escape aversive events Explanatry style- way peple make sense f bad events, peple with depressive r pessimistic explanatry style- see causes f bad events as internal, differ acrss cultures Scial learning- learning that takes place as a result frm direct scial interactinal Observatinal learning- by bserving thers, reprducing behaviur is called mdelling Vicarius cnditining- cnsequences f actin by bserving thers Tutelage- direct instructin