Module 17, 18, 19 Introduction to Learning

1. Module 17, 18, 19Introduction to Learning

2. Learning • …the relatively permanent change in a subject’s behavior to a given situation brought about by his (or her) repeated experiences in that situation, provided that the behavior change cannot be explained on the basis of native response tendencies, maturation, or temporary states of the subject (e.g., fatigue, drugs, etc.).

3. Learning “A relatively permanent change in an organism’s behavior due to experience”

4. Are These Examples of Learning?Why or Why Not? 1. The cessation of thumb sucking by an infant. 2. The acquisition of language in children. 3. A computer program generates random opening moves for its first 100 chess games and tabulates the outcomes of those games. Starting with the 101st game, the computer uses those tabulations to influence its choice of opening moves. 4. A worm is placed in a T maze. The left arm of the maze is brightly lit and dry; the right arm is dim and moist. On the first 10 trials, the worm turns right 7 times. On the next 10 trials, the worm turns right all 10 times.

5. Examples of Learning? 5. Ethel stays up late the night before the October GRE administration and consumes large quantities of licit and illicit pharmacological agents. Her combined (verbal plus quantitative) score is 410. The night before the December GRE administration, she goes to bed early after a wholesome dinner and a glass of milk. Her score increases to 1210. Is the change in scores due to learning? Is the change in pretest regimen due to learning? 6. A previously psychotic patient is given Dr. K’s patented phrenological surgery and no longer exhibits any psychotic behaviors. 7. A lanky zinnia plant is pinched back and begins to grow denser foliage and flowers.

6. Examples of Learning? 8. MYCIN is a computer program that does a rather good job of diagnosing human infections by consulting a large database of rules it has been given. If we add another rule to the database, has MYCIN learned something? 9. After pondering over a difficult puzzle for hours, Jane finally figures it out. From that point on, she can solve all similar puzzles in the time it takes her to read them. 10. After 30 years of smoking two packs a day, Zeb throws away his cigarettes and never smokes again.

7. Watson’s Extreme Environmentalism • “Give me a dozen healthy infants, well-formed, and my own special world to bring them up in, and I’ll guarantee to take any one at random and train him to be any type of specialist I might select - doctor, lawyer, artist, merchant-chief, and yes, beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors.” • John Broadus Watson, 1928

8. Types of Learning • Observational Learning • watch & learn • Associative Learning • link two events • Classical Conditioning • associate two stimuli and anticipate events • Operant Conditioning • associate our behavior and its consequence and act according to our best interest

9. Observational Learning • We can learn from other’s experiences and examples.

10. Associative Learning • Linking two events that occur close together Someone is shot. First you hear the sound of the shot, then see the blood. You associate guns with danger – the linking of events..

11. Associative Learning

12. Associative Learning

13. Associative Learning If you’ve seen the movie, Jaws, you probably had a feeling that danger was just around the corner. This is “associative learning.” http://www.youtube.com/watch?v=wCfWHqrYUqo

14. Conditioning – the process of learning associations • Classical – associating two stimuli and thus anticipating events.

15. Classical Conditioning • We learn to associate two stimuli

16. Classical and Operant Conditioning Classical: • We learn to associate two stimuli and thus anticipate events. Operant: • We learn to associate a response and its consequence and thus repeat acts followed by rewards and avoid acts followed by punishment.

17. Classical Conditioning Ideas of classical conditioning originate from old philosophical theories. However, it was the Russian physiologist Ivan Pavlov who elucidated classical conditioning. His work provided a basis for later behaviorists like John Watson. Sovfoto Ivan Pavlov (1849-1936)

18. Ivan Pavlov Father of Classical Conditioning… …noticed that when he put food (UCS) in a dog’s mouth, the dog would salivate (UCR).

19. So…he added a neutral stimulus, which became the (CS) and produced a (CR)

20. Classical Conditioning Explained http://www.youtube.com/watch?v=cP5lCleK-PM

21. Condition your Friends!!! http://www.youtube.com/watch?v=6D205B7WgJE&NR=1

22. Classical Conditioning Terms UCS – unconditioned stimulus UCR – unconditioned response CS - conditioned stimulus CR – conditioned response Extinction – diminishing a conditioning when a response is no longer reinforced Generalization – once a response has been conditioned, similar stimuli elicit similar responses

23. Pavlov’s Apparatus • Harness and mouth tube help keep dog in a consistent position to gather uncontaminated saliva samples

24. Before Conditioning • Before Stimuli Are Paired • Unconditioned Stimulus (UCS) elicits Unconditioned Response (UCR) • Meat elicits salivation • Neutral stimulus (NS) elicits no particular response • The bell does not lead to a particular response

25. During Conditioning • Conditioning: Neutral Stimulus (NS) is paired with the Unconditioned Stimulus (UCS) • Bell rings, then meat powder is delivered • This pairing happens a number of times (trials)

26. After Conditioning • After several trials, when the bell rings, the dog salivates (NO FOOD NEEDED!) • The Bell is now a Conditioned Stimulus (CS) • Salivation is now a Conditioned Response (CR)

27. Pavlov’s Classic Experiment

28. Classical Conditioning Terms • Acquisition • Formation of a learned response to a stimulus through presentation of an unconditioned stimulus • Extinction • Elimination of a learned response by removal of the unconditioned stimulus • Generalization • When the classically conditioned reaction occurs to other (similar) stimuli

29. Acquisition Acquisition is the initial learning stage in classical conditioning in which an association between a neutral stimulus and an unconditioned stimulus takes place. In most cases, for conditioning to occur, the neutral stimulus needs to come before the unconditioned stimulus. The time in between the two stimuli should be about half a second.

30. Acquisition The CS needs to come half a second before the US for acquisition to occur.

31. Extinction When the US (food) does not follow the CS (tone), CR (salivation) begins to decrease and eventually causes extinction.

32. Spontaneous Recovery After a rest period, an extinguished CR (salivation) spontaneously recovers, but if the CS (tone) persists alone, the CR becomes extinct again.

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

34. Stimulus Discrimination Discriminationis the learned ability to distinguish between a conditioned stimulus and other stimuli that do not signal an unconditioned stimulus.

35. Extending Pavlov’s Understanding Pavlov and Watson considered consciousness, or mind, unfit for the scientific study of psychology. However, they underestimated the importance of cognitive processes and biological constraints.

36. Cognitive Processes Early behaviorists believed that learned behaviors of various animals could be reduced to mindless mechanisms. However, later behaviorists suggested that animals learn the predictability of a stimulus, meaning they learn expectancy or awareness of a stimulus (Rescorla & Wagner, 1972).

37. Biological Predispositions Pavlov and Watson believed that laws of learning were similar for all animals. Therefore, a pigeon and a person do not differ in their learning. However, behaviorists later suggested that learning is constrained by an animal’s biology.

38. Biological Predispositions Garcia showed that the duration between the CS and the US may be long (hours), but yet result in conditioning. A biologically adaptive CS (taste) led to conditioning but other stimuli (sight or sound) did not. Courtesy of John Garcia John Garcia

39. Biological Predispositions Even humans can develop classically to conditioned nausea.

40. Pavlov’s Legacy Pavlov’s greatest contribution to psychology is isolating elementary behaviors from more complex ones through objective scientific procedures. Ivan Pavlov (1849-1936)

41. Applications of Classical Conditioning • Former crack cocaine users should avoid cues (people, places) associated with previous drug use. • Through classical conditioning, a drug (plus its taste) that affects the immune response may cause the taste of the drug to invoke the immune response.

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

43. What Can a Hippo learn? http://www.youtube.com/watch?v=G3NueKXS6dk

44. Classical conditioning links horror movie music to fear Scary Music Fear Gore UCR NS UCS

45. Classical conditioning links horror movie music to fear Scary Music Fear Gore UCR NS UCS Scary Music Fear CR CS

46. Learning Factors • Number of pairings • Reliability of CS in predicting UCS • Occurrence of CS just before UCS

47. UCS (passionate kiss) UCR (sexual arousal) CS (onion breath) UCS (passionate Kiss) UCR (sexual arousal) CS (onion breath) CR (sexual arousal) Classical Conditioning

48. Acquisition (CS+UCS) Strength of CR Spontaneous recovery of CR Extinction (CS alone) Extinction (CS alone) Pause Classical Conditioning

49. Timing of CS before UCS

50. Prepared Classical Conditioning • Organisms seem predisposed to make certain associations e. g., nausea creates taste aversions Exp: drinking Exp: Garcia