Effects of temporal contexts and contextual habituation on latent inhibition.

BACKGROUND Latent inhibition of conditioned taste aversion (CTA) is sensitive to external and internal cues. Time of day can serve as an internal cue, and latent inhibition may be reduced if the pre-exposure and conditioning stages occur at different times of day. This contextual cue attributed to a change in the time of day may reveal a temporal specificity of latent inhibition. Although the habituation period to spatial contexts is a determinant variable for the spatial specificity of latent inhibition of CTA, the influence of contextual-temporal familiarity (time of day) on latent inhibition of CTA has not been explored through direct comparisons between different periods of habituation to the temporal context. METHOD Two different periods of contextual habituation (short vs. long) previous to taste pre-exposures were compared in Wistar rats to analyze the influence of these periods on the temporal specificity of latent inhibition of CTA. RESULTS A long period of habituation, in relation to a short period, facilitated the effect of a change of the time of day between pre-exposure and conditioning on the magnitude of taste aversion. CONCLUSIONS A long habituation to temporal contexts facilitates the temporal specificity of latent inhibition of CTA.