Control of taste-aversion extinction by exteroceptive cues

Abstract

In Experiment 1, four groups of rats were given a paired presentation of saccharin and lithium chloride in the presence of either a novel animal compartment (two groups) or a novel noise-producing fluid bottle (two groups). During extinction trials, given in the presence/absence of the compartment or bottle cues, no differences of saccharin-intake emerged. After the extinction period, saccharin-preference tests were given in the presence of the novel exteroceptive cue present at conditioning. It was found that reinstatement of the particular type of bottle present at conditioning resulted in a strong taste aversion, while reinstatement of the animal compartment present at conditioning had no such effect. In Experiment 2, three groups of rats were conditioned in the presence of novel “noisy” bottle cues. During extinction trials, saccharin was presented either in “noisy” bottles or in “silent” bottles in either the presence or absence of the noise from the “noisy” bottles. It was found that the groups receiving “silent” bottles drank more than the group receiving the “noisy” bottles. Subsequent preference tests in the presence of the original “noisy” bottle cues indicated that only the former groups retained a saccharin aversion.