Effects of stimulus preexposure on the generalization of conditioned taste aversions in infant rats.

Generalization of a conditioned taste aversion in infant rats and how this is affected by stimulus preexposure was investigated in a series of experiments. In Experiment 1 generalization of a conditioned aversion between two tastes (sweet and salty) was found, and the effect of tastes preexposure was a reduction in generalization (Experiment 2). However, when these tastes were combined with a common taste (acid) that was less (Experiment 3) or more intense (Experiment 3b), the effect of stimulus preexposure was a stronger generalization of the conditioned aversion. In this case, a reduction on generalization was again observed by increasing the number of preexposure trials to the taste compounds (Experiment 4). In all cases the generalization levels were directly related to the effect of stimulus preexposure on the acquisition rate of conditioning. It can be concluded that, with the appropriate parameters, a reduction of generalization of a conditioned taste aversion can be obtained after taste exposure in preweanling rats. Copyright 1999 John Wiley & Sons, Inc.