1. Human Learning
Topic 3: Part 3 Respondent Conditioning Mechanisms
and Function
CEDP 324 Ryan Sain, Ph.D. 1 3/30/2012

2. Contingency & Contiguity
 Contingency is a major key!
 the degree of prediction from the CS to the US effects the amount of
conditioning
 Rescorla – p(us/cs) and p(us/no cs)
 Vary these probabilities using a 2 minute tone at random intervals
 .4 that the US would occur during a CS; .2 a US would occur during a no
CS
 Contiguity also plays a role
 The shorter the ISI or TI the stronger the conditioning
CEDP 324 Ryan Sain, Ph.D. 2 3/30/2012

3. Compound Stimuli
 Two or more stimuli occurring
together (sound and sight -
CR) then paired with a US
 Can test the effects of this by
presenting one of the CSs
alone after pairings
 Often you get conditioning to
both
 But not always
CEDP 324 Ryan Sain, Ph.D. 3 3/30/2012

4. Blocking
 Kamin – conditioned suppression procedure
(css = light, tone, light tone; cr = shock)
 Two groups: blocking and control
 One stimulus seems to block conditioning to the
other – no new predictability.
Group Phase 1 Phase 2 Test Result
Phase
Blocking 1 Light Light/tone Tone Tone elicits
no CR
Control ------- Light/tone Tone Tone elicits
CR
CEDP 324 Ryan Sain, Ph.D. 4 3/30/2012

5. Overshadowing
 Intensity of the CS effects conditioning trials
 Loud CS and soft CS  US = CR
 Test with either CS
 +CS = CR
 -CS ≠ CR
 But you can then use the –CS by itself and
get conditioning
 One seems to overshadow the other
CEDP 324 Ryan Sain, Ph.D. 5 3/30/2012

6. Experience with the CS
 Latent inhibition
 Presence of a CS in the
absence of the US
 Delays acquisition in the
future
 Prediction is decreased
CEDP 324 Ryan Sain, Ph.D. 6 3/30/2012

7. Acquisition
• CR is increasing in strength
Strength of CR
•Learn more on early trials than on later
ones
Number of trials
CEDP 324 Ryan Sain, Ph.D. 7 3/30/2012