Lectures 12 & 13: Pavlovian Conditioning (Learning-Performance) Learning, Psychology 5310 Spring, 2015 Professor Delamater

Pavlovian Learning Three Key Questions 1. What are the major determinants of learning? 2. What is the content of learning? 3. How does learning get translated into performance?

Pavlovian Learning: Factors Affecting the Conditioned Response 1.Nature of the US 2.Nature of the CS 3.CS-US Interval 4.Decision Processes: Timing & I/T, Comparator Theory The discussion of how learning gets translated into performance in Pavlovian conditioning has led to a variety of interesting studies showing that a number of factors affect the form of the CR as well as whether or not the CR will occur in different situations. Now we’ll consider some of this work.

Nature of the US & CR Form Pigeon autoshaping task, and the form of the CR was monitored Jenkins & Moore (1973) study Red Keylight – Grain Green Keylight – Water

Nature of the US & CR Form Pigeon autoshaping task, and the form of the CR was monitored Pigeons pecked the keylight as though it was food with the Grain US, but “sip” the keylight with a Water US. This shows that the nature of the US determines CR form. Jenkins & Moore (1973) study Red Keylight – Grain Green Keylight – Water

Nature of the US & CR Form Bidirectional UR studies Context – Morphine conditioning (Siegel) results in Drug tolerance (see right) But why? CS evokes a conditioned response that is opposite the primary response produced by the drug. Why? Because the drug evokes a bidirectional UR, and the CS gets conditioned to the second phase of the UR.

Nature of the US & CR Form Bidirectional UR studies Context – Morphine conditioning (Siegel) results in Drug tolerance (see right) But why? CS evokes a conditioned response that is opposite the primary response produced by the drug. Why? Because the drug evokes a bidirectional UR, and the CS gets conditioned to the second phase of the UR.

Nature of the CS & CR Form Learning rat shows more biting responses to the wood block CS than in the control group. However, the learning rat shows more social grooming responses displayed to the live rat CS than in the control group. This result is against the stimulus substitution theory prediction, and shows that the nature of the CS determines the form of the observed CR. Timberlake & Grant Experiment (1975) Expt Gp 1:Wood Block CS – Food pellets paired Ctrl Gp 1:Wood Block CS | Food pellets unpaired Expt Gp 2:Live Rat CS – Food pellets paired Ctrl Gp 2:Live Rat CS | Food pellets unpaired Stimulus Substitution Theory - CS substitutes for the US Prediction: Learning rat should respond to the wood block and rat CSs in the paired groups in the same way, namely, by biting them.

CS-US Interval and CR Form Sexual conditioning in Japanese Quail Cue light is paired with access to female quail CS-US interval is 1 min or 20 min, in different groups Control groups are exposed to cue light CS and female US unpaired With short CS-US interval, the male quail displays a conditioned approach CR, but with a long CS-US interval he displays a conditioned general locomotor activity CR. Akins, et al Experiment (2000)

Behavior Systems Theory Behavior systems (for different motivational states) have a hierarchical organization. General, Focal, and Consummatory Modes each consist of different sets of behaviors and stimulus-response sensitivities. Pavlovian conditioning is thought to interface with these underlying behavior systems, such that the nature of the CS, the US, and the CS-US interval should all help determine the form of the CR. For example, with a relatively short CS-US interval Focal mode CRs will be conditioned, but with a long CS-US interval General Search mode CRs will be conditioned. Timberlake (2001), Domjan (1997), Rau & Fanselow (2007)

Decision Processes The development of CRs to a CS is related to the I/T Ratio: higher ratios promote faster acquisition of conditioned responding. This is thought to reflect differences in the decision whether or not to respond to the CS. In other words, does the CS convey better temporal information as to the arrival of the US compared to the overall rate of US occurrence? If so, then the animal will “decide” to respond to the CS. US Timing and the I/T Ratio, (Gibbon & Balsam, Gallistel & Gibbon, Balsam & Gallistel) CS US Etc … CS – US Interval = T (“Trial” time to the US) Inter-US Interval = I (time between USs) T I

Decision Processes Conditioned excitatory responding will be seen if the associative strength conditioned to the CS is greater than that conditioned to the relevant comparator stimulus. The CS will produce inhibitory responding if the reverse is true. Once again, the CR is thought of as the product of a decision process that involves a comparison between different sources of information about US occurrence. Comparator Theory, (Miller & Matzel, 1988; Stout & Miller, 2007) Associative strength to the CS is compared to Associative strength to “comparator” stimuli (e.g., the experimental context)