1 PSYCHOLOGY (8th Edition, in Modules) David Myers PowerPoint Slides Worth Publishers, © 2007

2 Classical Conditioning Module 21

3 Classical Conditioning How Do We Learn? Classical Conditioning  Pavlov’s Experiments  Extending Pavlov’s Understanding  Pavlov’s Legacy

4 Definition Learning is a relatively permanent change in an organism’s behavior due to experience. Learning thus is more flexible, unlike genetically programmed behaviors of say, Chinooks.

5 How Do We Learn? We learn by association. Our minds naturally connect events that occur in sequence. Aristotle, 2000 years ago, suggested this law of association. Then 200 years ago Locke and Hume reiterated this law.

6 Stimulus-Stimulus Learning Learning to associate one stimulus with another.

7 Stimulus-Stimulus Learning Learning to associate one stimulus with another.

8 Response-Consequence Learning Learning to associate a response with a consequence.

9 Response-Consequence Learning Learning to associate a response with a consequence.

10 Ideas a of classical conditioning originate from old philosophical theories, however it was a Russian physiologist Ivan Pavlov who elucidated classical conditioning. His work became seminal for later behaviorists like John Watson and B. F. Skinner. Classical Conditioning Ivan Pavlov ( ) Sovfoto

11 Pavlov’s Experiments Before conditioning food (Unconditioned Stimulus, US) produces salivation (Unconditioned Response, UR). The tone (neutral stimulus) does not.

12 Pavlov’s Experiments During conditioning, neutral stimulus (tone) and US (food) are paired resulting in salivation (UR). After conditioning neutral stimulus (now Conditioned Stimulus, CS) elicits salivation (now Conditioned Response, CR)

13 Acquisition The initial stage in classical conditioning. during which association between a neutral stimulus and a US takes place. 1.Neutral stimulus needs to come before the US for conditioning to occur (most cases). 2.The time between the two stimuli should be about half a second.

14 Acquisition The CS needs to come half a second before the US to cause acquisition.

15 Extinction When a US (food) does not follow a CS (tone) CR (salivation) starts to decrease and at some point goes extinct.

16 Spontaneous Recovery After a rest period an extinguished CR (salivation) spontaneously recovers and if CS (tone) persists alone becomes extinct again.

17 Stimulus Generalization Tendency to respond to stimuli similar to CS is called generalization. Pavlov conditioned the dog’s salivation (CR) by using miniature vibrators (CS) to the thigh. When he subsequently stimulated other parts of the dog’s body, salivation dropped.

18 Stimulus Discrimination Discrimination is the learned ability to distinguish between a CS and other stimuli that do not signal a US.

19 Extending Pavlov’s Understanding Pavlov and Watson considered consciousness or mind not fit for scientific study of psychology. However, they underestimated the importance cognitive processes and biological constraints.

20 Cognitive Processes Early behaviorists believed that learnt behaviors of various animals could be reduced to mindless mechanisms. However, later behaviorists suggested that animals learn predictability of a stimulus, thus learn expectancy or awareness of a stimulus (Rescorla, 1988).

21 Biological Predispositions Pavlov and Watson believed that laws of learning were similar across all animals. Learning in a pigeon and a person was not different. However, later behaviorists suggested that learning was constrained by animal’s biology.

22 Biological Predispositions John Garcia Garcia showed that duration between CS and US can be long (hours) and yet result in conditioning. Biologically adaptive CS (taste) led to conditioning and not others (light or sound). Courtesy of John Garcia

23 Biological Predispositions Even humans develop classically conditioned nausea.

24 Pavlov’s greatest contribution to psychology is isolating elementary behaviors from more complex ones through objective scientific procedures. Pavlov’s Legacy Ivan Pavlov ( )

25 Watson used classical conditioning procedures to develop advertising campaigns for a number of organizations including Maxwell House, making “coffee break” an American custom. Applications of Classical Conditioning John B. Watson Brown Brothers

26 1.Alcoholics can be conditioned (aversively) partly reversing their positive-associations with alcohol. 2.A drug (plus its taste) that affects the immune response, can lead the taste to invoke the immune response through classical conditioning. Applications of Classical Conditioning