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.
SD
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∆
Stimulus Delta –
A stimulus in the presence
of which a given behavior has
not produced reinforcement in
the past.
Natural Example
Arbitrary Stimulus
S∆
No “Ring”
Target Behavior
None
SD
“Ring”
“Hello”
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 SD 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
Behavior
Postcedent
Go
Stop
Absence of
Ticket
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
Behavior
Postcedent
Go
Stop
Absence of
Ticket
2) Jimmy
Stimulus
Outside
Behavior
Postcedent
Talking
Loud
Got in Trouble
Talking Loud
Absence of
Trouble
3) Daniel
Stimulus
Behavior
Postcedent
Pretty Girl
“Suck My
Dick”
Slapped in
Face
“Suck My
Dick”
Laughed
4) Alex
Stimulus
Job
Interview
Behavior
Postcedent
15 minutes
late
Negative
Social Impact
15 minutes
late
Positive Social
Impact
5) Stephen
Stimulus
Yesterday
around
buddies
Behavior
Postcedent
Joke about
9/11
Positive
Social Impact
Joke about
9/11
Negative
Social
Impact
Stimulus Control
The same behavior, elicited by a
stimuli, can have different
consequences.
Often times we have to train or retrain 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. SD)
“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)
2)
3)
If A=B,
And B=C,
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
Key
A- Spoken Word, B – Picture,
C – Written Word
Bicycle
Teach A=B
Stimulus Equivalence
Key
A- Spoken Word, B – Picture,
C – Written Word
Bicycle
Teach B=C
Stimulus Equivalence
Key
A- Spoken Word, B – Picture,
C – Written Word
Bicycle
Bicycle
Equivalence A=C
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.