Brain mechanisms of conditioned taste aversion learning: A review of the literature

Overall, the evidence indicates that taste aversion learning, as contrasted with traditional passive avoidance, is unusually resistant to disruption.

Abstract

Animals appear to be innately predisposed to associate such food-related stimuli as taste with internal consequences, such as illness. The neural mechanisms of this taste aversion learning are poorly understood, but have recently been the object of increased experimental scrutiny. This article reviews several dozen published reports concerning the effects of central nervous system manipulations on acquisition and retention of taste aversions. Overall, the evidence indicates that taste aversion learning, as contrasted with traditional passive avoidance, is unusually resistant to disruption. The lateral and ventromedial hypothalamus and the amygdala are consistently implicated as participants in taste aversion learning, although their precise role is unclear. Results of studies dealing with other structures are contradictory and inconclusive. Methodological problems contributing to this confusion are discussed, and potentially profitable directions for further research are indicated.