Discrimination & Complex Stimulus Control

1. Discrimination & Complex Stimulus Control Chs12 & 13

2. Reinforcement-Based Discrimination SD After Behavior Before SD After

3. Discriminative Stimulus (SD) • A stimulus in the presence of which a particular response will be reinforced or punished

4. S-delta (SD) • A stimulus in the presence of which a particular response will not be reinforced or punished

5. Reinforcement-Based Discrimination SD Brelandlesss target After Chicken has food Behavior Chicken pulls the trigger Before Chicken has no food After Chicken has no food SD Breland

6. Discrimination Training Procedure • Reinforcing or punishing a response in the presence of one stimulus and extinguishing it or allowing it to recover in the presence of another stimulus.

7. Stimulus discrimination(stimulus control) • The occurrence of a response more frequently in the presence of one stimulus than in the presence of another, usually as a result of a discrimination training procedure

8. Differential Reinforcement vs. Stimulus Discrimination

9. Concept training • Intuition? • Control by a concept or set of contingencies the person or organism does not define or describe • Concept of PERSON is complex

10. Herrnstein & Loveland • Concept training procedure with nonverbal animal

12. Concept Training SD Various pictures of people After Pigeon has grain Behavior Pigeon pecks key Before No grain Sdelta Various pictures with no people After Pigeon has no grain

14. Concept Training SD Various Picasso paintings After Pigeon has grain Behavior Pigeon pecks key Before No grain Sdelta Various painting by others After Pigeon has no grain

18. Complex Stimulus Control • Conceptual stimulus control

19. Stimulus class (concept) • A set of stimuli all of which have some common physical property • A stimulus class is the same thing as a concept

20. Stimulus generalization • The behavioral contingencies in the presence of one stimulus affects the frequency of the response in the presence of another stimulus • E.g. – reinforcement for pecking in presence of 1 Picasso painting affects likelihood of pecking in presence of another Picasso painting (more likely)

21. Concept Training • Reinforcing or punishing a response in the the presence of one stimulus class and extinguishing it or allowing it to recover in the presence of another stimulus class

22. Concept trainingVs. Conceptual stimulus control

23. Conceptual stimulus control • Responding occurs more often in the presence of one stimulus class and less often in the presence of another stimulus class because of concept training

24. Testing for stimulus generalization • Test for stimulus generalization using novel stimuli • If respond correctly to novel stimuli, can say the behavior is under the stimulus control of concepts.

25. Stimulus generalization vs. stimulus discrimination • Responds in presence of SD but not in the presence of SD. This is ______________ • Responds at similar rates in presence of SD and SD. This is __________________

26. Stimulus Generalization

27. Stimulus Discrimination

28. Stimulus-Generalization Gradient

29. Generalization vs. Discrimination • Amount of generalization is the opposite of the amount of stimulus discrimination (stimulus control)

30. Fading, Errorless Learning, Imitation Chapter 13 & 14, Part 2

31. Fading • Stimulus dimensions • The physical properties of stimuli

32. Stimulus Dimensions • Stimuli differ from each other • House vs. car • Obvious dimensions • Size, weight, shape, material, etc. vs.

33. Stimulus Dimensions • The more dimensions along which objects differ, the easier to establish a discriminative stimulus control • The fewer dimensions along which objects differ, the harder it is to establish discriminative stimulus control

34. Example • Good golf balls (SD) vs. bad golf balls (SD) • This is a discrimination that is difficult • How can the discrimination be established? • The 2 golf balls are similar in so many dimensions….and differ in only a few • Roundness, resiliency, hardness of cover

35. Make stimulus dimensions more salient, then use fading • Color the bad golf ball green • Leave the good golf ball alone • Reinforce picking out good golf balls • Don’t reinforcer picking bad (green) golf balls

36. Fading • Gradually fade out the difference between good balls and bad balls by reducing the “green”

37. Fading procedure • At first, the SD and the SDdiffer along at least two stimulus dimensions (green & white, new & old). • The difference between the SD and the SDalong all but one dimension is reduced until there is no difference along the reduced dimensions. • The the SD and the SDdiffer along only one dimension

38. Errorless Discrimination Procedure • The use of a fading procedure to establish a discrimination, with no errors during training. Jimmy

39. Jimmy Susan

40. Jimmy Susan

41. Jimmy Susan

42. Jimmy Susan

43. Jimmy Susan

44. Jimmy Susan

45. Reinforcement-Based Discrimination SD Jimmy on a white  black card After Jimmy has a raisin Behavior Jimmy picks card Before Jimmy has no raisin After Jimmy has no raisin SD Susan on a black card

46. Stimulus Dimensions • Lettering • Shading • At first, choice of cards was under the control of the dimension of ________ • Then, after fading, responding was under the control of the dimension of _______

47. Techniques of Gradual Change

48. Reinforcer Reduction • Move from primary to secondary reinforcers • Change from 3 pellets to 1 pellet

49. Imitation • The form of the behavior of the imitator is controlled by similar behavior of the model

50. Imitation Training: Stimulus Discrimination SD Raised arm and “do this” After Marilla has food & praise Behavior Marilla raises arm Before Marilla has no food & praise After Marilla has no food & praise SD No arm raised or no “do this”