Disentangling the effects of context change and context familiarity on Latent Inhibition with a Conditioned Taste Aversion procedure

Contextual specificity of Latent Inhibition (LI) has been demonstrated using an ample range of experimental procedures. Context dependence has not been consistently obtained, however, when LI has been induced using a Conditioned Taste Aversion (CTA) procedure. This paper presents two experiments designed to analyze whether the context plays the same role in LI with a CTA paradigm as compared to other Pavlovian techniques. Experiment 1 compared the effect on LI of a context change between the conditioning and test stages as a function of whether the testing context was new or the animals’ home cage. The results of this experiment showed that using the animals’ home cage as context at testing enhanced the expression of LI. Experiment 2 manipulated context novelty and familiarity beforehand to introduce different context changes. The results indicate that, as compared to the no context change condition, the strength of LI increased when the conditioning context was different from that of preexposure and testing (ABA). Conversely, a context change from preexposure to conditioning/test stages (ABB) disrupted LI, but only when the animals had been pre-familiarized with the new context introduced at conditioning. These results are similar to those obtained with other conditioning procedures different from CTA.