Taste neophobia: Neural substrates and palatability

Abstract Animals, including humans, are reluctant to eat a new food because they have no information about the content—whether it is safe to eat or poisonous. In fact, on first encounter with a novel edible, most animals will eat only a small amount of the new food and in the ensuing seconds to hours wait to discover the postingestive consequences. If the edible has no aversive systemic effects, then more of the food will be consumed on subsequent encounters until the food is recognized as safe. Conversely, if aversive postingestive effects are experienced, the animal learns to refrain from eating the food on subsequent encounters. The initial reluctance to eat the new food is termed taste (or more generally food) neophobia and the acquired knowledge that the food is poisonous is called a conditioned taste aversion (CTA). My aim in this chapter is to examine the neural substrates and nature of taste neophobia, which will also include its relationship with CTA learning. In order to provide background and perspective, I will begin by noting some of the characteristics of taste neophobia and CTA. The primary focus of the chapter, however, will be the recent research from my laboratory, which supports a novel conceptual analysis that goes beyond the scope of the traditional view of these phenomena.