CHEMOSENSORY FUNCTION AND DYSFUNCTION

Taste and smell are fundamental sensory systems essential in nutrition and food selection, for the hedonic and sensory experience of food, f or efficient metabolism, and, in general, for the maintenance of a goo d quality of life. The gustatory and olfactory systems demonstrate a d iversity of transduction mechanisms, and during the last decade, consi derable progress has been made toward our understanding of the basic m echanisms of taste and smell. Understanding normal chemosensory functi on helps clarify the molecular events that underlie taste and smell di sorders. At least 2,000,000 Americans suffer from chemosensory disorde rs-a number that is likely to grow as the aging segment of the populat ion increases. Smell disorders are more frequent than taste disturbanc es, due to the vulnerability and anatomical distinctiveness of the olf actory system, and because a decline in olfactory function is part of the normal aging process. Common gustatory and olfactory complaints ar e due to a number of medications, to upper respiratory infections, to nasal and paranasal sinus diseases, and to damage to peripheral nerves supplying taste and smell. Most chemosensory complaints have an ident ifiable cause. Although diagnosis of taste and smell disorders has imp roved considerably over the last two decades, treatment of these disor ders is still limited to conditions with discernible and reversible ca uses. Future research is needed for a better understanding of chemosen sory mechanisms, establishing improved diagnostic procedures, and diss eminating knowledge on chemosensory disorders among practitioners and the general public.