Gustatory neural processing in the hindbrain.

Abstract

Sensory neurophysiology must account for sensation and perception. Given the richness and complexity of our auditory and visual worlds, this remains a daunting charge even after decades of sophist icated visual and auditory neurophysiology. Taste, on th� other hand, should be easy. It contains little of the spatial and tempQral dimensions found in vision, audition, or somesthesis, and humans report only a few taste categories or qualities. In English, the most common are sweet, salty, sour , and bitter . Given this apparently simpler task, how does gustatory neurophysiology acquit itself? Gustatory neurophysiological data, primarily from rodents, match human quality judgments moderately well, but the degree of this success or failure depends upon the theoretical bias of the beholder , as well as on the scope of the gustatory responses included. Taste per se may have only a few sensory categories, but other attributes contribute complexity and richness to the sensory experience that leaves present neurophysiological data far behind. The absence of obvious stimulus dimensions continues to impede neuro­ physiological analysis of gustatory sensibility. The molecules that elicit similar verbal reports of taste from humans and neural activity in gustatory afferent nerves often bear little chemical relation to one another . Sugars,