1. The Rescorla-Wagner Model
Associative model of conditioning
You are not responsible for the math model (4.1)
Concept of surprise in a mathematical model
Surprise increases associative strength
This is the typical learning curve
With repeated experience surprise goes down
With repeated experience growth of associative strength slows down
see Figure 4.17

2. This figure will not be covered on the exam
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.

3. Evaluation of the Rescorla-Wagner Model
Effective in explaining the blocking effect
Able to predict Overexpectation of a US effect
Not adequate to explain negative conditioning

4. The Blocking Effect
Kamin (1968) demonstrates that just temporal contiguity is not sufficient for learning
Procedure see Figure 4.15
Phase 1: Pair CSa (tone) with US (footshock)
Phase 2: Pair CSa (tone) and CSb (light) with US (footshock)
Phase 3: Test CSa (tone) only and CSb (light) only
Conditioning to tone is strong, but conditioning to light is weak
Tone blocked the acquisition of an association between light and the footshock
Kamin – US has to be surprising to be effective – the US was not surprising because it was well predicted by the tone
Interesting example using geometric cues see figure 4.16

5. tone
shock
tone + light
Figure 4.15 – Diagram of the blocking procedure.
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.

6. FIGURE 4.16
Blocking in human learning about geometric cues. Human participants had to move a cursor to the correct geometric location (indicated by + in each triangle) on conditioning trials in Phase 1 (for the blocking group) and Phase 2 (for all groups). Percent correct during the test trials is indicated in the third column (based on Prados, 2011).
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.

7. Evaluation of the Rescorla-Wagner Model
Novel Prediction: Overexpectation of a US
Overexpectation of a US results in the loss of associative value despite pairings with US
Phase 1:    CSa -> US, and CSb -> US
Each independently perfectly predicts the US
Phase 2:    CSa + CSb -> US
Summation of associative strength is greater than the US can support
Both CSa and CSb will loose associative strength until the sum of their associative strengths is equal
See Figure 4.18

8. Figure 4.18 – Diagram of the overexpectation experiment
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.

9. Evaluation of the Rescorla-Wagner Model
Conditioned Inhibition: see figure 4.19
CS US; and CS+/CS no US
Initial overexpectation of the US on CS+/CS- trials
Associative value of CS+/CS- must sum to zero to accurately predict the absence of the US
This can be accomplished by making the associative value of the CS- negative.
Extinction of conditioned inhibition does not occur as predicted
Because extinction is not simply the reverse of acquisition
Can not produce negative associative conditioning

10. The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.

11. Attentional Models of Conditioning
Pearce-Hall (1980)
CS-processing model
Pay attention to a CS that could become predictors of US
Pay attention to the CS when US is surprising
With experience the CS is a good predictor of US
If the US was predicted, then attention to the CS declines
If the US was not predicted, then attention to the CS increases

12. Timing and Information Theory Models
Temporal coding Hypothesis
In addition to forming a CS-US association
Learn the temporal CS – US pattern and US - US pattern
For example timing of conditioned eyeblink see fig 3.9
Sexual condition where CS-US interval influences conditioned see fig 4.9
Can also learn the inter trial interval (ITI) which indicates frequency of US
Relative waiting time hypothesis
Knowledge of both CS-US interval and US-US interval predicts the ratio of the ISI to ITI
ISI also called trial duration or just “T “ how long you wait for US during CS
ITI : is shortened to just “I” how long you wait from US to US
ITI / ISI is the I/T ratio
I/T ratio
Low ratios provide less information about timing of CS-US
High ratios provide good predictions of the CS-US relationship
See figure 4.21

13. FIGURE 4.21 T is CS – US interval I = 120 sec T = 20 sec I = 60 sec
Percentage of time rats spent nosing the food cup during an auditory CS in conditioning with either a 10-second or a 20-second trial duration (T) and various intertrial intervals (I) that created I/T ratios ranging from 1.5 to Data are shown in relation to responding during baseline periods when the CS was absent. (Based on “Trial and Intertribal Durations in Appetitive Conditioning in Rats,” by P. C. Holland, 2000, Animal Learning & Behavior, Vol. 28, Figure 2, p. 125.)
T is CS – US interval
I = 120 sec
T = 20 sec
I = 60 sec
T = 10 sec
I is US – US interval
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.