Dysgeusia: Experimental Evidence Running head: Dysgeusia: Experimental evidence Dysgeusia: Experimental evidence suggesting Neurological Impairment in Taste Perception among the Elderly and HIV-infected patients

Dysgeusia, characterized as an altered perception of taste to any one of the four major tastant qualities (sweet, salt, sour, and bitter), is frequently experienced after dental anesthesia and neuroma (middle ear) surgery. Many medications, ranging from antiinflammatory drugs and protease inhibitors to antihypertensive drugs such as amiloride, have also been found to disrupt gustatory perception. Possible peripheral sites of damage are confined primarily to the two major gustatory nerves, the chorda tympani and the glossopharyngeal nerve. Studies addressing central nervous system impairment have focused mainly on the NST (nucleus of solitary tract), where taste input from these two cranial nerves converge, and the somatosensory cortex in the frontal lobe. Experiments involving cranial nerve blocks and crushes in laboratory animals have greatly enhanced our knowledge of the complex interactions between the chorda tympani and the glossopharyngeal nerves. This paper reviews literature concerning deficits in the peripheral gustatory system due to medications and injury.