Anesthesia of the Chorda Tympani Nerve and Taste Phantoms

• Published in: Physiology & behavior Vol. 63; no. 3; pp. 329 - 335
• Main Authors: Yanagisawa, K., Bartoshuk, L.M., Catalanotto, F.A., Karrer, T.A., Kveton, J.F.
• Format: Journal Article
• Language: English
• Published: Cambridge Elsevier Inc 01.02.1998; New York, NY Elsevier
• Subjects: Adult; Anatomical correlates of behavior; Anesthesia; Anesthesia, Local; Behavioral psychophysiology; Biological and medical sciences; Chorda tympani nerve; Chorda Tympani Nerve - physiology; Dysgeusia; Female; Fundamental and applied biological sciences. Psychology; Glossopharyngeal nerve; Glossopharyngeal Nerve - physiology; Humans; Male; Middle Aged; Phantom; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; quinine; Quinine - pharmacology; Sodium Chloride - pharmacology; Taste; Taste - physiology; Tongue - innervation; Tongue - physiology; Glossopharyngeal nerve; Phantom; Anesthesia; Taste; Dysgeusia; Chorda tympani nerve; Human; Tongue; Chorda tympani; Gustatory pathway; Gustation; Perception; Chemical stimulus
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/S0031-9384(97)00423-X

Yanagisawa, K., L. M. Bartoshuk, F. C. Catalanotto, T. A. Karrer, and J. F. Kveton. Anesthesia of the chorda tympani taste nerve and taste phantoms. PHYSIOL BEHAV 63(3) 329–335, 1998.—The chorda tympani nerve innervates the anterior two-thirds and the glossopharyngeal nerve, the posterior one-third, of each side of the tongue. Previous work showed that anesthesia of one chorda tympani increased the perceived intensity of quinine applied to an area innervated by the contralateral glossopharyngeal nerve, but decreased the perceived intensity of NaCl applied to an area innervated by the ipsilateral glossopharyngeal nerve. The data presented here corroborate that earlier finding and show that if both chorda tympani nerves are anesthetized, the taste of quinine is intensified and the taste of NaCl diminished at areas innervated by the glossopharyngeal on both sides of the tongue. In about 40% of the subjects, tastes occurred in the absence of stimulation (we call these tastes phantoms). The phantoms were usually localized to the posterior tongue contralateral to the anesthesia and they were abolished when a topical anesthetic was applied to the area where they were perceived. Phantoms like these may be a source of clinical dysgeusia in patients with localized taste damage. The phantoms may result because the anesthesia releases inhibition normally occurring between the central projection areas of different taste nerves.