Stimulus Control Justin Daigle, BCBA, LBA

Stimulus “An energy change that affects an organism through is receptor cells” (Michael, 2004, p.7) Note: Stimulus is singular. Stimuli is plural.

Stimulus Stimuli is a part of an organism’s environment. Includes both overt and covert events. Overt – Able to be seen by an observer Covert- Private Events

Stimulus An stimulus is considered arbitrary when there is no connection between the stimuli and the behavior.

SDSD Discriminative Stimulus – A stimulus in the presence of which responses of some type have been reinforced and in the absence of which the same type of responses have occurred and not been reinforced

S∆S∆ Stimulus Delta – A stimulus in the presence of which a given behavior has not produced reinforcement in the past.

Natural Example Arbitrary Stimulus No “Ring” “Ring” None “Hello” S∆S∆ SDSD Target Behavior

Stimulus The only stimulus that controlled the behavior was the “ring” We can say that the phone ringing has stimulus control over the behavior of answering the phone.

Stimulus Control A situation in which the frequency, latency, duration, or amplitude of a behavior is altered by the presence or absence of an antecedent stimulus.

In Other Words If an S D can accurately elicit a target behavior, that SD has stimulus control over the target behavior.

Examples I only smoke when I’m at a bar. I only drink when I’m sad. I jam Alanis Morrissette when I’m angry. Just seeing Jim makes me angry.

Punishment A behavior can come under stimulus control both by reinforcement (as our previous definition suggested) or by punishment.

Nat’l Ex - Punishment Stimulus Go Stop Absence of Ticket PostcedentBehavior

Stimulus Control Game Instructions: On a piece of paper, write the numbers 1-5 vertically. In each example a behavior and with two consequences will be given. Write down what you image to be the stimuli that control the behavior.

1) Danielle Stimulus Go Stop Absence of Ticket PostcedentBehavior

2) Jimmy Stimulus Talking Loud Outside Absence of Trouble PostcedentBehavior Got in Trouble Talking Loud

3) Daniel Stimulus “Suck My Dick” Pretty Girl Laughed PostcedentBehavior Slapped in Face “Suck My Dick”

4) Alex Stimulus 15 minutes late Job Interview Positive Social Impact PostcedentBehavior Negative Social Impact 15 minutes late

5) Stephen Stimulus Joke about 9/11 Yesterday around buddies Negative Social Impact PostcedentBehavior Positive Social Impact Joke about 9/11

Stimulus Control The same behavior, elicited by a stimuli, can have different consequences. Often times we have to train or re- train stimuli to elicit specific behaviors.

Real Life Example Student: Eion Age: 7 Target Behavior: Stereotypy In Sessions: A “Red” card was placed on a specified spot on a visual schedule when stereotypy would be blocked (or punished)

Real Life Example Because of the need for school: Eion was taught only to engage in stereotypy in the presence of a green card on his desk.

Real Life Example This was later generalized to be a rubber band or rubber bracelet on his wrist. During P.E. or recess, he was given the green bracelet and stereotypy was not interfered with.

Real Life Example While wearing the red bracelet, Eoin never engaged in the target behavior. He was allowed to wear the green bracelet less and less over the years until it was not needed.

Real Life Example Eoin is now 25 and will occasionally wear a red bracelet when he feels like it going to be a “bad day”.

Concept Formation In Behavior Analysis, words like “concept” is a hypothetical construction; however, during teaching, we observe our clients understanding the concept behind the trial.

Concept Formation In Behavior Analysis, we do accept concept formation. It is a complex example of stimulus control. The stimuli is generalized across a stimulus class.

Stimulus Class A group of stimuli that share specified common elements: - Form (e.g. size, color) - Function (e.g. S D ) “Touch” and “Point to” both elicit the same behavior. Both phrases are in a stimulus class.

Feature Stimulus Class When members of a stimulus class share a common physical form or common relative relations. Ex. Black lab and a blood hound have similar features – both are dogs.

Arbitrary Stimulus Class When members of a stimulus class do not share a common stimulus feature Ex. Seeing 50%, ½, divided evenly, or.5 will elicit the same target behavior – halving.

Stimulus Equivalence Justin Daigle, BCBA, LBA

Stimulus Equivalence The emergence of accurate responding to untrained and non-reinforced stimulus-stimulus relations following the reinforcement of responses to some stimulus-stimulus relations.

Stimulus Equivalence Developed by Murray Sidman in a landmark 1971 study. Based on mathematical statements

Stimulus Equivalence 1) If A=B, 2) And B=C, 3) Then A=C

Stimulus Equivalence A, B, and C are all variables. So for our examples, let’s define them: A = Spoken Word “Bicycle” B = Picture of Bicycle C = Written word Bicycle

Stimulus Equivalence A- Spoken Word, B – Picture, C – Written Word Key Bicycle Teach A=B

Stimulus Equivalence A- Spoken Word, B – Picture, C – Written Word Key Bicycle Teach B=C

Stimulus Equivalence A- Spoken Word, B – Picture, C – Written Word Key Bicycle Equivalence A=C Bicycle

Reflexivity The teaching of A=A (Matching to Sample)

Symmetry The understanding that if A=B, then B=A

Transitivity Understanding the final “jump” without training. A=C and C=A

Conclusion The learner must exhibit Reflexivity, Symmetry, and Transitivity in order to prove Stimulus Equivalence.

Further Reading Sidman, M. (1971). Reading and auditory-visual equivalences. Journal of Speech and Hearing Research, 14, 5-13.