Super-latent inhibition with delayed conditioned taste aversion testing

Abstract

In three conditioned taste aversion experiments with rats, latent inhibition (LI) was examined as a function of the time interval (1 or 21 days) between the conditioning and the test phases. In Experiments 1 and 2, the effects of US intensity on LI were examined. LI increased in the 21-day condition, as compared with the 1-day condition, with medium and high US intensity, but not with weak US intensity. Groups not preexposed to the CS flavor had similar aversions when testing was conducted 1 day after conditioning, as compared with 21 days. In Experiment 3A, delay-induced super-LI was obtained when the delay was spent in the home cage and the experimental stages took place in a different context (as in Experiments 1 and 2). In Experiment 3B, when all the stages, including the delay period, were conducted in the home cage, there was no super-LI effect. The modulation of delay-induced super-LI as a function of US intensity and context extinction is discussed in relation to association deficit and retrieval interference theories of LI.