Oral Chemesthesis and Taste

Chemesthesis describes the sensation evoked by exogenous chemical stimuli that activate somatic nociceptive fibers. In particular, oral chemesthesis is elicited by irritant compounds found commonly in foods and is conveyed from the oral mucosa by the trigeminal nerve. In recent years, an abundance of information has been generated regarding the transduction and coding mechanisms that initiate chemesthetic sensations. Furthermore, neural underpinnings have been identified that explain many of the psychophysical observations made in the preceding three decades. The initial section of this chapter provides a detailed overview of the anatomy and physiology that governs chemesthesis. Additionally, much of the work done over the last few decades are summarized and discussed in the context of more recent findings. Finally, the last section discusses the impact of oral irritants on taste. Interestingly, despite the profusion of work identifying mechanisms of chemesthesis, little information has been generated regarding irritant-taste interactions. This is especially surprising given that oral irritants are often found in foods that are commonly consumed. Psychophysical studies describing interactions between oral irritation and taste are discussed and the neural mechanisms that may contribute to these phenomena are addressed.