Learning

1. Learning • Learning • relatively permanent change in behavior due to experience • Associative Learning • learning that two events occur together • two stimuli (classical conditioning) • a response and its consequences (operant conditioning)

2. Two related events: Stimulus 1 Lightning Stimulus 2 Thunder Result after repetition Stimulus We see lightning Response We wince anticipating thunder Classical /Pavlovian Conditioning • We learn to associate two stimuli

3. Response: Pushing vending machine button Consequence:Receiving a candy bar Operant Conditioning • We learn to associate a response and its consequence

4. Learning • Behaviorism • John B. Watson • Psychology… • should be an objective science • should study behavior without reference to mental processes

5. Classical/Pavlovian Conditioning • Ivan Pavlov • 1849-1936 • Russian physician/ neurophysiologist • Nobel Prize (1904) • studied digestive secretions

6. Classical/Pavlovian Conditioning • Classical Conditioning • organism comes to associate two stimuli • lightning and thunder • tone and food • begins with a reflex • a neutral stimulus is paired with a stimulus that evokes the reflex • neutral stimulus eventually comes to evoke the reflex

7. Classical/Pavlovian Conditioning • Pavlov’s device for recording salivation

8. Classical/Pavlovian Conditioning • Unconditioned Stimulus (UCS) • stimulus that unconditionally triggers a response • natural & automatic • food • Unconditioned Response(UCR) • unlearned, naturally occurring response to the unconditioned stimulus • salivation when food is in the mouth • Unconditioned = Unlearned

9. Classical/Pavlovian Conditioning • Conditioned Stimulus (CS) • originally neutral stimulus that, after association with an unconditioned stimulus, comes to trigger a conditioned response • Conditioned Response (CR) • learned response to a previously neutral conditioned stimulus • Conditioned = learned

10. Before Conditioning UCS (food in mouth) Neutral stimulus (tone) UCR (salivation) No salivation During Conditioning After Conditioning UCS (food in mouth) CS (tone) Neutral stimulus (tone) UCR (salivation) CR (salivation) Pavlov’s Classic Experiment

11. Classical/Pavlovian Conditioning • Acquisition • the initial stage of classical conditioning • a response is established and gradually strengthened • associating a neutral stimulus with an unconditioned stimulus so that the neutral stimulus starts to evoke a conditioned response

12. Classical/Pavlovian Conditioning • Extinction • diminishing of a conditioned response • when an unconditioned stimulus does not follow a conditioned stimulus • example: if tone is repeatedly sounded without food, dogs will salivate less and less

13. Acquisition (CS+UCS) Strong Spontaneous recovery of CR Extinction (CS alone) Strength of CR Extinction (CS alone) Weak Pause Time Classical/Pavlovian Conditioning

14. Classical/Pavlovian Conditioning • Spontaneous recovery • reappearance, after a rest period, of an extinguished conditioned response • Generalization • tendency to respond to stimuli that are similar to the conditioned stimulus

15. 60 Drops of saliva in 30 seconds 50 40 30 20 10 Hind paw Pelvis Shoulder Front paw 0 Thigh Trunk Foreleg Part of body stimulated Generalization

16. Classical/Pavlovian Conditioning • Discrimination • learned ability to distinguish between a conditioned stimulus and other irrelevant stimuli • dogs learned to respond to a specific tone and not to other tones

17. UCS (drug) UCR (nausea) CS (waiting room) UCS (drug) UCR (nausea) CS (waiting room) CR (nausea) Nausea Conditioning among Cancer Patients

18. UCS (loud noise) UCR (fear) CS (rat) UCS (loud noise) UCR (fear) CS (rat) CR (fear) Stimulus similar to rat (such as rabbit) Conditioned fear (generalization) Little Albert’s Fear Conditioning

19. Operant Conditioning • Operant Conditioning • type of learning in which organisms associate their own actions with consequences • behavior is strengthened if followed by reinforcement • diminished if followed by punishment • Law of Effect • Thorndike’s principle that rewarded behavior is likely to recur

20. Classical vs. Operant Conditioning • Operant Behavior • complex or voluntary behaviors • push button, perform complex task • operates (acts) on environment • produces consequences • Respondent Behavior (Classical Conditioning) • occurs as an automatic response to some stimulus (salivating in response to meat and a tone)

21. Operant Conditioning • B.F. Skinner (1904-1990) • elaborated Thorndike’s Law of Effect • developed behavioral technology

22. Operant Conditioning • Operant Chamber (“Skinner Box”) • bar pressed by animal to obtain food/water reinforcement • device attached to record rate of pressing

23. Operant Conditioning • Shaping • Reinforcers (e.g., food) gradually guide actions toward a desired behavior • http://www.youtube.com/watch?v=mm5FGrQEyBY

24. Operant Conditioning • Reinforcer • any event that strengthens the behavior it follows • Positive reinforcement • strengthens a response by presenting a pleasurable stimulus • Negative reinforcement • strengthens a response by removing something unpleasant

25. Principles of Reinforcement • Primary Reinforcer • innate • satisfies a biological need (e.g., food) • Secondary Reinforcer • conditioned (learned) • money; good grades • Immediate and Delayed Reinforcers • Delayed gratification (think back to the kids & marshmallows video!)

26. Schedules of Reinforcement • Continuous Reinforcement • reinforcing the desired response each time it occurs • extinction occurs rapidly • Partial (Intermittent) Reinforcement • reinforcing a response only part of the time • results in slower acquisition • greater resistance to extinction • gambling; occasionally giving in to tantrums

27. Schedules of Reinforcement • Fixed Ratio (FR) • schedule that reinforces a response only after a specified number of responses • the faster you respond, the more rewards you get • different ratios • very high rate of responding • like piecework pay • example: free sub after buying 10

28. Schedules of Reinforcement • Variable Ratio (VR) • reinforces a response after an unpredictable number of responses • slot machines; fly fishing • very hard to extinguish because of unpredictability

29. Schedules of Reinforcement • Fixed Interval (FI) • reinforces a response only after a specified time has elapsed • response occurs more frequently as the anticipated time for reward draws near • checking cookies in oven

30. Schedules of Reinforcement • Variable Interval (VI) • schedule that reinforces a response at unpredictable time intervals • produces slow, steady responding • like pop quiz

31. Number of responses Fixed Ratio 1000 Variable Ratio Fixed Interval 750 Rapid responding near time for reinforcement 500 Variable Interval 250 Steady responding 0 10 20 30 40 50 60 70 80 Time (minutes) Schedules of Reinforcement

32. Punishment • aversive event that decreases the behavior that it follows

33. Problems with Punishment • Punished behavior is not forgotten, it's suppressed • May just learn discrimination (behavior not okay in one setting, but still does it elsewhere) • Causes increased aggression • shows that aggression is a way to cope with problems

34. Problems with Punishment • Creates fear • Does not necessarily guide toward desired behavior • Punishment often just teaches how to avoid the punishment • Most psychologists favor emphasis on reinforcement • Notice what the individual is doing right and affirm them for it

35. Comparison of Classical and Operant Conditioning Classical Conditioning Operant Conditioning The response Involuntary, automatic “Voluntary,” operates on environment Acquisition Associating events; CS announces Associating response with a conse- UCS. quence (reinforcer or punisher). Extinction CR decreases when CS is repeatedly Responding decreases when reinforce- presented alone. ment stops. Cognitive Subjects develop expectation that Subjects develop expectation that a processes CS signals the arrival of UCS response will be reinforced or punished; they also exhibit latent learning, without reinforcement. Biological Natural predispositions constrain Organisms best learn behavior similar to predispositions stimuli and responses can easily be their natural behaviors; unnatural be- associated. haviors instinctively drift back toward natural ones. Operant vs Classical Conditioning

36. Observational Learning • Observational Learning • learning by observing and imitating the behavior of others • Modeling • process of observing and imitating behavior • Prosocial Behavior • positive, constructive, helpful behavior • opposite of antisocial behavior

37. Observational Learning • Albert Bandura • pioneer researcher of observational learning • Bobo Doll Study • http://www.youtube.com/watch?v=vdh7MngntnI

38. Negative Observational Learning antisocial effects TV – powerful source of observational learning Link between viewing violence and aggressive behavior Desensitization – become increasingly indifferent to violence after prolonged exposure