AUTONOMIC AND BEHAVIORAL-CORRELATES OF APPETITIVE CONDITIONING IN RATS

The cardiac responses accompanying conditioned stimulus-(CS)-generated (orienting) and unconditioned stimulus- (US)-generated appetitively m otivated behaviors (P. C. Holland, 1977) were investigated. On the bas is of contemporary psychophysiological research, CS-generated response s were predicted to produce bradycardia, and US-generated responses to produce tachycardia. Pairing a 10-s visual CS with food delivery prod uced conditioned behavioral orienting (rearing) during the initial por tion of the CS, followed by magazine approach (US-generated) responses as the CS progressed. CS onset produced a decrease in heart rate, med iated by an increase in parasympathetic stimulation of the heart, whic h persisted throughout the 10-s CS; no support for a biphasic cardiac response was observed. These data are discussed with respect to other conditioned autonomic responses and their relevance to foraging and fo od ingestion.