Learning Psychology 1106 12/29/2018
Introduction What is learning? Some event at time 1 influences behaviour at time 2 (Rescorla) Good as any definition, better than many The 2 simples forms of learning are habituation and sensitization Repeated stimulation Shows up in aplysia Shows up in humans 12/29/2018
Classical or Pavlovian Discovered by Pavlov Dog salivated when food was put in its mouth Buzzer paired with food Buzzer elicited salivation! 12/29/2018
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Key terms UCS UCR CS CR The CR Like the UCR Sometimes not as strong Sometimes preperatory 12/29/2018
Spit and twitches CS must overlap in time with the UCS If the CS is extinguished before the UCS we call it trace conditioning Not nearly as effective Backward sonditioning UCS -> CS Rarely works Conditioning takes many CS UCS pairings or trials 12/29/2018
The Phases of Learning Acquisition Asymptote While the animal is learning the association After a long period of acquisition (or not so long) responding levels off Asymptote The leveled off bit If we pair the UCS with nothing, we get Extinction CR disappears 12/29/2018
Phases on stun Say you go back, oh a day later, after extinction You will get responding! Spontaneous recovery Same thing happens in habituation too 12/29/2018
A few more key terms Once we have conditioning we can get generalization Similar stimulus elicits a weaker response, but a response nonetheless The opposite of this is discrimination Animal is trained to respond to one stimulus, but that the other leads to no US Excitatory conditioning Inhibitory conditioning 12/29/2018
Newer ideas It has been updated to deal with cognitive effects, most notably by Rescorla and Wagner They talk about associative strength and predictability Correlation of events blocking 12/29/2018
old control group, animal learns what? CS + CS- CS+ CS- CS+ CS- Rescorla Control CS+ CS+ CS+ CS+ CS+ 12/29/2018
Blocking Group Phase 1 Phase 2 Test Result Control Nothing LT+ T CR No CR 12/29/2018
Other cool stuff Not just a many trial phenomenon Taste aversions John Garcia Rats associate sickness with taste Very long ISI One trial With birds it is colour! 12/29/2018
Just a few more points Has showed up in most every species tested Association of events is pretty darned important Methods have been adopted for application Phobias Aversive counterconditioning 12/29/2018
Operant Conditioning Pavlovian conditioning involves associating a stimulus (CS) with a UCR (or some variation thereof) The response would normally be elicited Eyeblink Salivation BF Skinner called these behaviours respondents Sort of automatic or innate things 12/29/2018
Operant Conditioning Operant conditioning involves associating a behaviour with an outcome Original idea came from EL Thorndike’s Law of Effect Skinner developed the Skinner Box to study learning Animals can b e shaped to do stuff though successive approximations 12/29/2018
Reinforcement A reinforcer is an event that increases responding Negative reinforcers are the removal of an even which, in its removal, causes an increase in responding Primary reinforcers have intrinsic biological value Food water 12/29/2018
Reinforcement Secondary reinforcers are learned Money for example While we can give reinforcement immediately Or they can be given schedules Schedules are much more effective 12/29/2018
Schedules of Reinforcement Fixed Interval First response after a given interval is rewarded FI Scallop Variable Interval Like FI but varies with a given average Scallop disappears 12/29/2018
Schedules of Reinforcement Fixed Ratio Reinforcement is given after a given number of responses A little less smooth Variable Ratio After a varying number of responses 12/29/2018
Operant stuff Skinner figured that these schedules (and many other, more complicated ones) could explain lots of stuff, well, most everything actually Punishment reduces behaviour But…. 12/29/2018
Animal cognition Just like all other parts of psychology, the cognitive revolution affected the study of animal learning Tolman really got it going Latent learning 12/29/2018
Animal Cognition The Brelands Olton and Samuelson and the radial maze Steve Vander Wall’s work on Clark’s nutcrackers Sara Shettleworth’s work Cognition in non humans is a generally accepted idea 12/29/2018
Conclusions about animal cognition Animals can do some amazing things Keep track of time Navigate Remember lots of stuff Do not try to get inside their heads Skinner’s ideas are out of date, but his methods, and the Skinner Box, are still used 12/29/2018
Applications Token economies IO psych Clinical settings 12/29/2018
Observational Learning People and probably orangutans can learn from observing others Modeling Bandura’s work TV violence How long lasting? Hmm, if you censor, what re you modeling? 12/29/2018