Generalization of conditioned aversion and limbic lesions in rats

The effect of lesions in the amygdala or dorsal hippocampus on the acquisition and generalization of a taste aversion was investigated. Rats were conditioned to avoid a 16% sucrose solution using a two-bottle technique. Once conditioning was established, a bottle containing the 16% solution was paired with either a 32, 24, 8, or 4% sucrose solution or water for 30 min/day for 5 days. No differences were observed in either the number of days to acquisition or in generalization gradients for any of the conditioned-aversion groups. In the generalization test, these subjects demonstrated a preference for sucrose concentrations below 16%. Control animals that received injections of saline rather than poison demonstrated a significantly lower preference relative to the poisoned animals for the lower sucrose concentrations.