Stimulus Control and Language

1. Stimulus Control and Language

2. Why is Understanding Stimulus Control so Important in Teaching Children with Autism? • “Because the aim of virtually all instruction is to get specific responses to occur reliably under particular antecedent stimulus conditions, all instructional techniques involve manipulations of antecedent stimuli, along with manipulations of consequent stimuli” (Green, 2001, p. 74)

3. Why is Understanding Stimulus Control so Important in Teaching Children with Autism? • Spradlin and Brady (1999) conceptualized the impairments in language and social skills in children with autism… • as limitations in the development of stimulus control

4. Social Skill Deficiencies • Appear very early in life • as young as several months old • By 1-year old many showed • Less eye contact • Imitate less • Less likely to point out objects to others • Failed to engage in reciprocal games such as pat-a-cake and peek-a-boo • Less symbolic or make beileve play • Less likely to recognize social emotional responses in other people

5. Communication Skill Deficits • Less likely to • demonstrate multiple nonverbal communicative behavior such as joint attention • Response to names & verbal directions • More likely to request than label

6. Spradlin and Brady (1999) • Proper stimulus control may not develop in children with autism because social stimuli do not function as reinforcers • It has been suggested that the patterns of the human face and physical contact serve as primary reinforcers for typically developing infants • Some children with autism avoid such contact • Do faces and hugging not serve as reinforcers from infancy? • What impact would this have on the development of other reinforcers? Social interactions? Language? • Proper stimulus control may not develop because children with autism require more consistentrelationships between antecedents, responses, and consequences…

7. Classical Conditioning Limitations • Infants developed conditioned responses by pairing various social stimuli with stimuli that elicited the rooting response. • E.g., mother’s voice or even footstep • Perhaps children with autism fail to develop such conditioned responses • The natural world is inconsistent in its pairing of social stimulus with unconditioned stimuli • Perhaps children with autism require more consistent pairings than other infants for conditioning to occur or may be more likely to be conditioned to nonsocial aspects of their physical environment.

8. Limitations in Learning Simple Discrimination • Perhaps children with autism require that a higher percentage of responses in the presence of a stimulus be followed by the same consequence, if they are to come under the control of that stimulus. • Might explain why children with autism prefer playing with objects than people • Contingencies of physical world may be more reliable that the contingencies of the social world. • E.g., child gestures to parent may or may not be picked up. Child reaches out for object, always results in obtaining object

9. Limitations in Learning Simple Discrimination • Overselectivity • Lovaas found that children with autism often learn to respond to some of the stimulus but not to all of the stimulus of a complex stimulus • Sunberg & Partington (Cond Disc) • Truck in the presence of a truck and the spoken word truck • Typically developing child may respond “truck “ in the presence of just a truck after a few pairings, a child with autism may learn to only response “truck” in the presence of the spoken word

10. Limitations in Learning Simple Conditional Discrimination • Most conventional stimulus control is conditional • In the presence of discriminative stimulus a specific response will be reinforced only when conditional stimuli are present. • Typically developing children master this easily and their behavior is reinforced for a high percentage of response they make in the presence of such discriminative stimuli • Children with autism fail to make that conditional discrimination and may ultimately extinguish all responses to the discriminative stimuli • Social behavior: saying “come play with me” in the presence of Mom who is not otherwise engaged. Child with autism my try to initiate play all at the wrong times and eventually stop trying. Or initiate greetings all at the wrong times.

11. Social World Social contingencies are often inconsistent SD: Mom Reinforcer:Being held by Mom Response: Reach up But mom may not always hold you when you reach up And the way mom looks, smells, sounds, feels, and holds you may be different

12. Non-social World • Contingencies in the nonsocial physical world may be more consistent and reliable • So may be more easily learned by children with autism • Might explain why children with autism prefer playing with objects over people Reinforcer: Feel object in hand SD: Object Response: Reach out Getting to hold the object is consistent and the object is consistently the same

13. Limitations in Stimulus Class Acquisition Written spoken picture Word  word  of  actual dog DOG DOG a dog • Stimuli are linked by shared function not necessarily physical properties • Children with autism are limited in their development of stimulus classes consisting of members without defining physical properties • Leads to substantial limitations in language development • Can imitate speech but that speech might have no relation to the objects and events that are typically related to that speech • Or read but not understand what he is reading

14. Limitations in the Recombination of Minimal Stimulus-Response Units • Much of our behavior involves responding appropriately to relatively novel situations • Generalized imitation • Little similarity between what a child sees and the specific stimulus produced by the imitator's own behavior • Perhaps the development of generalized imitation occurs as the development of instruction following behavior • Multiple exemplar training results in learning a number of minimal stimulus response units when than may be recombined within the imitator is presented a novel combination of responses for imitation • Children with autism tend to imitate objects easier than people • Leads to substantial social skill deficit

15. Limitations in the Recombination of Minimal Stimulus-Response Units • Much of our behavior involves responding appropriately to relatively novel situations • Following a verbal instruction • By 2, most children can follow 3-word directions • Made on the basis of conditional discriminations • Children who can recombine units will be more effective because they have the appropriate word-object and word-action equivalences. • Recombinations of conditional discriminations and equivalences classes may be limited in children with autism • Child can complete complex chains of behavior if the chains were invariant but would fail to perform a series of responses on the basis of a novel instruction.

16. Use of Operant Teaching Methods • Of course we can teach children with autism by establishing stimulus control by structuring consistent relations between specified stimuli behavior and consequences

17. Procedures to Overcome Basic Reinforcers Problems • Classical conditioning and building motivational systems

18. Basic Discrimination Training Procedures • Establishing attending skills and eye contact through prompting and reinforcement • What type of prompts??

19. Establishing New Forms of Conditional Stimulus Control • Imitation • Direction following

20. Establishing New Forms of Conditional Stimulus Control • Identity matching (single mode) • Visual: visual • Auditory: auditory • Arbitrary matching (multimodal) • Visual: auditory • Auditory: visual

21. Teaching Recombination of Stimulus-Response Units • Teach direction following to promote recombination's • Give me, go get, put on • Plane, paper, coat • Test for generalization of any give me, go get, and put on instruction

22. Concept Formation • Complex stimulus control that results in: • Generalizationwithin a class of stimuli and • Discriminationbetween classes of stimuli

23. Stimulus Class (Cooper et al., 2007) • AKA Concept • Set of stimuli that occasion a common response These would probably be in the same stimulus class for most people

24. Types of Stimulus Classes (Fields & Reeve, 2000) • Perceptual Class • Stimuli in the set share some physical characteristics • Examples: dogs, flowers, children, chairs, cars, etc. • Relational Class • Stimuli in the set characterize some abstract relationship • Example: examples of “bigger than,” “same/different” • Equivalence Class • Stimuli do NOT share any physical characteristics (Stimuli “go together” just because society says so) • Example: numeral 1 = written one = spoken “WUN” Fields, L., & Reeve, K. F. (2000). Synthesizing equivalence classes and natural categories from perceptual and relational classes. In J. C. Leslie, & D. Blackman (Eds.). Experimental and applied analysis of human behavior (pp. 59-84). Reno, NV: Context Press.

25. Equivalence Classes: Definition • a finite group of physically disparate stimuli (no perceptual similarity) • stimuli become related solely as a function of teaching (Fields, Adams, Buffington, Yang, & Verhave, 1996; Fields, Reeve, Adams, Brown, & Verhave, 1991; Sidman & Tailby, 1982; Sidman, 1994) • Emergence of accurate responding to untrained and nonreinforced stimulus-stimulus relations • Following the reinforcement of responses to some stimulus-stimulus relations • An equivalence class must contain at least three stimuli (but often has many more)

26. Example Stimuli in a 3-Member Equivalence Class • Written word • Spoken word • A picture DOG “DOG”

27. Another Example CAT • Written word • Spoken word • A picture “CAT”

28. Stimulus Equivalence • Train: • Emergent Relations: • Symmetry: B A and CB • Transitivity: A  C • Equivalence: C A DOG “dog” B C A

29. Teaching & Testing Summary • We TAUGHT 2 conditional relations: • A  B • B  C • We TESTED for 4 EMERGENT (DERIVED) relations: • B  A symmetry • C  B symmetry • A  C transitivity • C  A equivalence • (Another set of tests for REFLEXIVITY (IDENTITY) is often omitted if the learner already has this skill in her repertoire: A  A; B  B; C  C )

30. Equivalence Class Training & Testing Procedures • Usually taught and tested with arbitrary match-to-sample (MTS) • Symbolic notation is used to outline training/testing procedures: • A, B, C, …N represent each of the disparate stimuli that will make up the class • 1, 2, 3, etc. notate the number of classes to be established • Thus, A1 = first stimulus in class 1; B3 = second stimulus in class 3; etc.

31. Training & Testing Procedures • To establish equivalence classes, at least two potential classes must be trained concurrently • training establishes both substitutability of all stimuli within a particular equivalence class in addition to discrimination between classes

32. Training & Testing Procedures • To establish equivalence classes with three members, at least two stimulus-stimulus relations must be trained for each potential class • Let’s consider our DOG and CAT potential equivalence classes • First train the AB relation (given stimulus A select stimulus B) • the word DOG (A1) is presented as a sample • The positive comparison (Co+) would be the spoken word dog (B1) (Selection would result in positive feedback or reinforcement) • the negative comparison (Co-) would be the spoken word cat (B2) (Selection would result in corrective feedback or no reinforcement)

33. Training AB relation DOG A1 CAT DOG B1 B2

34. Training & Testing Procedures • To train the AB relation • word CAT (A2) is presented as a sample • positive comparison (Co+) would be the spoken word cat (B2) (Selection would result in positive feedback or reinforcement) • negative comparison (Co-) would be the spoken word dog (B2) (Selection would result in corrective feedback or extinction)

35. Training AB relation CAT A2 CAT DOG B1 B2

36. Training & Testing Procedures • Once responding is 100% correct, we can conclude AB conditional relation has been learned • At this point we can either continue training more conditional discriminations or we can do our first test for an EMERGENT (DERIVED) RELATION (a conditional discrimination that emerges with no direct training history) • If the learner “knows” that A goes with B, can they demonstrate the reverse? (B goes with A) • This emergent relation shows SYMMETRY

37. TESTING BA symmetry relation CAT B2 CAT DOG A1 A2

38. TESTING BA symmetry relation DOG B1 CAT DOG A1 A2

39. Training & Testing Procedures • the BA conditional relation is called “symmetry” because the relation is a mirror image or reversal of the one directly trained (i.e., A=B then B=A) • At this point, we can continue training another conditional discrimination • Let’s train the BC conditional relation

40. Training BC relation DOG B1 C2 C1

41. Training BC relation CAT B2 C2 C1

42. Training & Testing Procedures • Once the BC conditional relation is learned, we can do our 2nd test for an EMERGENT (DERIVED) RELATION • If the learner “knows” that B goes with C, can they demonstrate the reverse? (C goes with B) • This emergent relation would show a SECOND SYMMETRY relation

43. TESTING CB symmetry relation C1 DOG CAT B1 B2

44. TESTING CB symmetry relation C2 DOG CAT B1 B2

45. Training & Testing Procedures • If CB symmetry TEST responding is 100% correct, we can continue testing for another EMERGENT (DERIVED) RELATION • If the learner “knows” that A goes with B, and B goes with C, can they demonstrate that A goes with C? • This emergent relation would show a TRANSITIVE relation

46. TESTING AC transitive relation DOG A1 C2 C1

47. TESTING AC transitive relation CAT A2 C2 C1

48. Training & Testing Procedures • If the AC transitive TEST responding is 100% correct, we have one last test for another EMERGENT (DERIVED) RELATION • If the learner “knows” that A goes with B, and B goes with C, can they demonstrate that C goes with A? • This emergent relation would shows a combination of symmetry and transitivity; it is called an EQUIVALENCE relation

49. TESTING CA equivalence relation C1 CAT DOG A2 A1

50. TESTING CA equivalence relation C2 CAT DOG A2 A1