Theoretical Analysis of Classical
Conditioning
Thomas G. Bowers, Ph.D.
Penn State Harrisburg
Adaptive Function of CR
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What adaptive contributions have been
made by an organisms ability to
demonstrate classical conditioning?
Organisms not only learn CS-UCS
relationships, they appear to be adaptive for
the organism
The relationships are often of biological
significance
CR That Oppose UCR
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Well trained animals demonstrate an
antagonistic CR to some aversive
stimulation
Examples include the conditioned
development of tolerance
Tolerance is a biological adaptation, the
adjustment of the body to maintain
homeostatic tone
CR That Oppose UCS
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For example, biological adjustment to
regular doses of most drugs or medications
Adaptation to the use of alcohol or
morphine, or any other psychoactive
substance
More recently, we have now considered the
role of classical conditioning in the
development of tolerance
CR That Oppose UCS
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Opponent process theory developed to
explain patterns of conditioning
Solomon & Corbit, 1974
Hedonic or emotional stimulus also
produces a later effect opposite of the initial
process
Referred to as process “a” or process “b”
CR That Oppose UCS
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Opponent process theory developed to
explain patterns of conditioning
“A” process develops early, but “B”
processes begin to occur earlier over time
These processes summate to attenuate the
overall response
Opponent Process Theory
a
Early trials
b
a
b
Later
trials
Opponent Process Theory
Early trials
Later
trials
Habituation
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Reduction of responding after many
stimulation trials
Can be understood by opponent process
models
What Is Learned in
Conditioning?
CS
UCS
S-R Learning
UCR
CR
UCS
S-S Learning
UCR
Some Processes
CS2 Buzzer
CS1 Light
Sensory Preconditioning Phase One
CS1 Light
Sensory Preconditioning Phase Two
UCS
Food
Some Processes
CS2 Buzzer
Test to CS 2 Yields CR
These results indicate CR occurs to
CS2, implying S-S learning
Some Processes
CS1
Light
UCS
Food
CS1
CS2
Buzzer
Second Order Conditioning
Some Processes
CS2
Conditioning occurs here, and may
seem to be due to S-R learning, but
S-S explanations are also possible
Test to CS 2 Buzzer
Explanations of Classical
Conditioning
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Mere CS-UCS pairing is not enough
There is also required to be a contingency
Example of the informative nature of
weather reports
Significance of Contingency
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Fear and anxiety results from aversive
circumstances
Anxiety is more reflective on noncontingent or difficult to predict
circumstances
Fear may be more stimulus bound
Conditioning Can Be Selective
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Kamin demonstrated blocking effects of one
of a set of compound stimuli
One stimulus provides redundant
information
Conditioned inhibition can develop if the
second stimulus signals safety
Rescorla Wagner Theory
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Describes negatively accelerated learning
curve
Vn = K( - V n-1)
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Where V is associative strength,  is the
change in response strength,  is the
asymptote of conditioning. K reflects
salience of the CS-UCS
Rescorla - Wagner Theory
V3
V2
V1
Rescorla - Wagner Theory
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Theory predicts redundant stimuli become
inhibitory, which is also demonstrated
experimentally
On the other hand, the theory does not
explain latent inhibition well
This develops to pre-exposure to the CS
Now thought of as learned irrelevance
Rescorla - Wagner Theory
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Accounted for by K in theory
Psychological significance has been the
source of debate