Chemically evoked sensations from single human taste papillae

Abstract

Early psychophysical studies of human taste papillae, using chemical stimuli, indicated that single papillae often have a broad taste quality range. Recent investigations, using both chemical and electrical stimulation, have contested this result; single papillae were observed to mediate only one of the so-called primary taste sensations (salty, sweet, bitter or sour). In each case the techniques used were such as to leave the conclusion open to doubt. The present study, employing an improved technique for chemical stimulation, corroborates the wide sensitivity range shown in the earlier studies. This result is in accord with the available anatomical and electrophysiological data. Moreover, it concurs with similar findings from all sensory modalities in support of the hypothesis that sensory receptors and afferent neurons typically have broad quality ranges, regardless of the characteristics of the phenomenal organizations derived from the information coded in this manner.