Potential Exam Questions
„
„
„
How is sensory preconditioning different from second
order respondent conditioning that was discussed
earlier?
What needs to be demonstrated before we sayy control
by a stimulus element was blocked rather than
overshadowed?
What is one similarity and one difference between
blocking and sensory preconditioning?
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The Rescorla
Rescorla--Wagner Model
„
„
„
Stresses temporal pairings of the CS and US and properties
of both the CS and the US to predict conditioning outcomes.
Describes the change in strength of the CS (∆V) to elicit the
CR after each pairing with the US.
Iss a complex
co p e model
ode that
t at includes:
c udes:
„
„
„
„
A value for CS stimulus salience & US effectiveness: (S)
A value for maximum possible potential CS strength: (VMAX)
A value for the current conditioned strength of the CS: (V)
A value for the strength of other stimuli or stimulus elements from
compound stimuli that could acquire conditioned strength: (VSUM)
∆V = S (VMAX - V - VSUM)
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Rescorla--Wagner Model
Rescorla
„
An example graph of the simple acquisition of
the CS function across presentations of CSCS-US
pairings.
The learning rate parameter refers to the stimulus
salience of the CS (S).
„ The US strength parameter refers to the level that
the CS strength cannot exceed (VMAX).
Example Graph
„
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1
The Importance of Context
According to RescorlaRescorla-Wagner
„
The critical concept in the Rescorla
Rescorla--Wagner Theory that sets
it apart from the other theories is VSUM
SUM.. (the effect of
multiple stimuli on conditioning)
„
„
This represents the “context” of the CS
CS--US pairings and accounts
for the loss of CS strength in US habituation studies.
Estes (1969) found that the other stimuli in the setting became
more salient than the CS over time when the US was presented
often without the CS and these stimuli overshadowed any control
by the original CS.
37
Operant Responses
„
„
„
„
An “operant” is a response that produces changes in the
environment and is affected by these changes.
The tendency for behavior to be influenced by its consequences
probably evolved slowly over time.
Organisms that could adapt their behaviors to their
environments survived and passed this characteristic on to their
offspring as part of the genetic endowment.
Therefore “operant conditioning” or learning from
consequences, is based on genetic endowment.
38
Operant Relationships Involve a
Contingency
„
„
A contingency refers to a relationship between
stimuli and behavior.
The most basic contingency is between a
behavior and its conseq
consequence.
ence
“When I flip the light switch (B
(Behavior) the light
comes on (C
(Consequence).”
B
C
39
2
The Three Term Contingency
„
„
„
Repeated contact with a behavior/consequence
relationship strengthens that relationship.
Antecedent stimuli become part of that
relationship
p if theyy consistentlyy precede
p
the
Behavior/
ehavior/C
Consequence relationship.
We now have a threethree-term contingency.
A
B
C
40
Discriminative Stimuli
„
„
Antecedent stimuli can become discriminative
stimuli if they consistently precede reinforced or
punished behavior.
A discriminative stimulus
stim l s (SD) can
evoke a response that was followed by
reinforcement in its presence or
„ inhibit a response that was followed by punishment
in its presence.
„
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SD Examples
„
„
„
The ring (stimulus) of your cell phone evokes
__________ (response).
Seeing a police car ahead (stimulus) as you drive
on the freewayy and are late for class evokes
___________ (response).
Seeing the word “signature” (stimulus) at the
bottom of a contract you want to complete
evokes ______________ (response).
42
3
Four Basic Contingencies
„
Two contingencies that INCREASE behavior.
„
„
„
Presenting a stimulus as a consequence is Positive
Reinforcement
Removing a stimulus as a consequence is Negative
Reinforcement
Two contingencies that DECREASE behavior.
„
„
Presenting a stimulus as a consequence is Positive
Punishment
Removing a stimulus as a consequence is Negative
Punishment
43
Interpreting Examples
„
„
Notice that “positive” means the same as
“presenting” and “negative” means the same as
“removing” in this context.
Do not confuse “positive” with “good” and
“negative” with “bad” when labeling consequences
as positive or negative reinforcers and punishers.
44
Response Deprivation
„
Access to behavior can serve as a reinforcer if
normal access to that behavior has been restricted such
that the frequency of the behavior falls below its
usual level.
„
If one usually reads 4 hours per day and access to
reading is restricted such that they are only able to
read 1 hour per day THEN access to reading could
be used as a reinforcer to strengthen another
behavior.
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4
Premack and the Relativity of
Reinforcement
Premack principle: access to a more frequently occurring activity
can be used to reinforce the frequency of an activity that occurs
less often.
If activity A occurs 5 times a day and activity B occurs 2 times a day, we can
increase the frequency of B by allowing access to A only after B occurs.
However……if
However……
if activity C occurs 8 times a day we would not be able to
increase this activity by allowing access to activity A only after C occurs
(this contingency would probably decrease activity C).
So……
So
……the
the success of activity A as a reinforcer is “relative
relative”” to whether we
are trying to increase activity B or C. That is what is meant by the
“relativity of reinforcement”
reinforcement”.
50
Extinction (the contingency of
discontinued reinforcement)
„
„
Withholding reinforcement for a previously reinforced response
is the procedure of extinction.
extinction.
The behavioral effects of extinction (or process of extinction)
extinction) has
immediate and longlong-term effects.
„
„
„
Immediate effects include increases in response frequency, variability,
f
force
andd emotional
i l responses.
Long--term effects include the gradual weakening of responding until if
Long
finally disappears (or returns to the prereinforcement level).
Discriminated extinction means that a stimulus is present when
extinction is in effect (S∆) and absent when extinction is not in
effect. The result is less responding during S∆.
52
Side Effects of Extinction
„
„
„
„
„
„
Extinction bursts of responding.
Increase in response variability
Emotional behavior (agitation and/or frustration)
Aggressive behavior
Resurgence (the appearance of other behaviors that
once produced reinforcement)
Depression
53
5
Resistance to Extinction
„
„
Responding that continues for a long time after
reinforcement is removed is more resistant to
extinction than responding that ends quickly after
reinforcement is removed.
Resistance to extinction is influenced by
„
„
„
„
„
The reinforcement schedule
The history of reinforcement
The magnitude of reinforcement and degree of deprivation
Previous experience with extinction
Discriminative stimuli for extinction
54
Extinction is Different than
Forgetting
„
„
In extinction, the response is evoked during conditions
similar to the training conditions but reinforcement is
omitted. As a result we see less responding over time.
In forgetting,
g
g a response
p
is trained and then time passes
p
with no opportunity to emit the response (the SDs are
absent). As a result we might see less responding when
the SDs are again presented.
55
Natural vs. Contrived
Contingencies
„
A natural contingency involves a
behavior/consequence relationship that currently exists
without additional manipulations.
„
„
Behavior maintained by natural contingencies is often said to
be “intrinsically
intrinsically motivated
motivated”..
A contrived contingency involves following a behavior
with a consequence that would not normally occur for
that behavior.
„
Behavior maintained by contrived contingencies is often said
to be “extrinsically motivated”.
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6
Natural Contingencies
„
„
„
„
Pain (consequence) following a fall (behavior)
Walking toward an object (behavior) and object gets
closer (consequence)
Assembling a toy (behavior) results in a functioning toy
(
(consequence),
)
Turning the wheel (response) and the auto goes in a
new direction (consequence) , etc.
57
Contrived Contingencies
„
„
„
Getting tokens (consequence) for completing tasks
(behaviors)
Getting paid (consequence) for doing a job (behavior)
Getting a grade (consequence) for writing a paper
(b h i ) etc.
(behavior),
58
The Contrived vs Natural
Consequences Debate
„
„
Some argue that providing contrived consequences for
behavior will reduce the naturally reinforcing effects of
the behavior (“extrinsic rewards destroy intrinsic
motivation”).
A meta
meta--analysis of much of the published research
found little or no effect of appropriately applied
extrinsic consequences on intrinsic motivation
(Cameron and Pierce (1994).
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7
A Behavioral Perspective of
Creativity
„
„
Skinner (1974) addressed “creativity” as a form of
“variations in behavior selected by their reinforcing
consequences”.
Being “creative” means
„
„
„
Behaving
B h i in
i novell ways AND/OR
Arranging conditions that produce novel variations in ones
responding.
Research example:
„
Pryor, Haag & O’Reilly (1969) “The creative porpoise:
Training for novel behavior”, Journal of the Experimental
Analysis of Behavior, 12, 653653-661
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Reinforcement Effects: Novelty
or Stereotypy?
„
„
„
Swartz (1982): reinforcement produced stereotyped responding
and discouraged creativity.
Neuringer (1986): novelty as the reinforced operant encouraged
creativity, stereotypy as the reinforced operant discouraged
creativity.
Therefore, the effects of reinforcement depend on the
contingencies::
contingencies
„ If the contingencies of reinforcement support stereotyped
responding, the reinforcement effect will be less creativity.
„ If the contingencies of reinforcement support novel or
creative responding, the reinforcement effect will be more
creativity.
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