Theoretical Analysis of Classical Conditioning Thomas G. Bowers, Ph.D. Penn State Harrisburg
Dec 27, 2015
Theoretical Analysis of Classical Conditioning
Thomas G. Bowers, Ph.D.
Penn State Harrisburg
Adaptive Function of CR
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
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
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
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
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
b
Early trials
a
b
Later trials
Opponent Process Theory
Early trials
Later trials
Habituation
Reduction of responding after many stimulation trials
Can be understood by opponent process models
What Is Learned in Conditioning?
CS
UCS UCR
S-R Learning
CR
UCS UCR
S-S Learning
Some Processes
Sensory Preconditioning Phase One
CS2 Buzzer
CS1 Light
CS1 Light
UCS Food
Sensory Preconditioning Phase Two
Some Processes
Test to CS 2 Yields CR
CS2 Buzzer
These results indicate CR occurs to CS2, implying S-S learning
Some Processes
Second Order Conditioning
CS1Light
UCSFood
CS1
CS2Buzzer
Some Processes
Test to CS 2 Buzzer
Conditioning occurs here, and may seem to be due to S-R learning, but S-S explanations are also possible
CS2
Explanations of Classical Conditioning 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
Fear and anxiety results from aversive circumstances
Anxiety is more reflective on non-contingent or difficult to predict circumstances
Fear may be more stimulus bound
Conditioning Can Be Selective
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
Describes negatively accelerated learning curve
Vn = K( - V n-1) 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
V1
V2
V3
Rescorla - Wagner Theory
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
Accounted for by K in theory Psychological significance has been the
source of debate