Specificity of cue to consequence in aversion learning in the rat: Control for US-induced differential orientations

Abstract

In four experiments, each using a single conditioning trial, rats avoided a light more than a saccharin solution after these stimuli had been paired with footshock, whereas saccharin was avoided more than the light after these stimuli had been paired with lithium injection. The use of a single conditioning trial precludes possible US-induced differential orientations from influencing which stimuli will be associated on the conditioning trial. This cue-consequence specificity effect was obtained even when subjects conditioned with lithium received a non­ contingent footshock prior to the test session, and when subjects conditioned with footshock received a noncontingent lithium injection before testing (Experiments 2-4l. Weak aversions to the light in rats given a light-lithium pairing and noncontingent footshock and to the sac­ charin in subjects that received a saccharin-footshock pairing and noncontingent lithium ad­ ministration were obtained in Experiment 2. However, these weak aversions were not ob­ tained when subjects were given three nonreinforced exposures to the test chamber before the test session (Experiments 3 and 4l. These results indicate that US-induced differential orientations do not mediate the cue-consequence effect in aversion learning.