Home
This Title All WIREs
WIREs RSS Feed
How to cite this WIREs title:
WIREs Cogn Sci
Impact Factor: 2.88

Gustation

Full article on Wiley Online Library:   HTML PDF

Can't access this content? Tell your librarian.

Abstract Much has been discovered over the last few decades about the anatomy and physiology of the human taste system, most notably its receptor mechanisms and intermodal factors that influence its function. While the taste system works in concert with the olfactory, somatosensory, auditory, and visual sensory systems to establish the overall gestalt of flavor, its primary specialization is to ensure that the organism obtains energy, maintains proper electrolyte balance, and avoids ingestion of toxic substances. Despite its focus on inborn functions, taste—like its sister sense of smell—is remarkably malleable, reflecting the need to adapt to changing circumstances and general nutrient availability. It is now widely appreciated that taste dysfunction is common in many diseases and disorders, and is a frequent side effect of a number of medications. This interdisciplinary review examines salient aspects of the human gustatory system, including its anatomy, physiology, and pathophysiology. WIREs Cogn Sci 2012, 3:29–46. doi: 10.1002/wcs.156 This article is categorized under: Psychology > Brain Function and Dysfunction

Schematic representation of the tongue demonstrating the relative distribution of the four main classes of lingual papillae, three of which have taste buds (indentations on insets represent taste buds). Taste buds are particularly plentiful on the sides of the foliate and circumvallate papillae. von Ebner's glands secrete materials into the valleys between the latter papillae. The fungiform papillae can vary considerably in size and are more dense on the tip and anterior lateral regions of the tongue. Copyright © 2011 Richard L. Doty.

[ Normal View | Magnified View ]

Identification of taste qualities is compromised by taking the drug terbinafine. Mean (SEM) number of trials correct for the identification of sweet, sour, bitter and salty tasting substances in six patients complaining of taste deficits following terbinafine usage (T; black bars) and in six matched controls (C; gray bars). The P values reflect the main effects of group in separate analyses of variance performed for each tastant. Copyright © 2005 Richard L. Doty.

[ Normal View | Magnified View ]

Age markedly depresses regional sensitivity to NaCl. Mean (± SEM) sensitivity values obtained from 12 young and 12 elderly subjects for sodium chloride presented to two tongue regions for three stimulation areas (12.5, 25, and 50 mm2) and three NaCl stimulus concentrations (0.01, 0.10, and 1.00 M). Note that the sensitivity of the older subjects was markedly depressed in all tongue regions and for all stimulus areas assessed. Unlike the young subjects, greater sensitivity was not seen on the tongue tip than on a more posterior tongue site. (Reprinted with permission from Ref 90. Copyright 1995 Oxford University Press)

[ Normal View | Magnified View ]

Distribution of cranial nerves to taste regions. CN VII fibers from the geniculate ganglion innervate taste buds on the anterior portion of the tongue and on the soft palate. CN IX fibers from cell bodies within the petrosal ganglion innervate taste buds on the foliate and circumvallate papillae of the tongue, as well as pharyngeal taste buds. CN X fibers from cell bodies in the nodose ganglion innervate taste buds on the epiglottis, larynx, and esophagus. (Modified with permission from Ref 48. Copyright 1962 Ciba Pharmaceutical Company)

[ Normal View | Magnified View ]

Relative sensitivity of the edge of the tongue to the four classic taste qualities. Sensitivity reflects the reciprocal of the threshold value and is plotted as a ratio of maximum sensitivity. Note that all regions of the tongue that were evaluated were responsive to some degree to all stimuli, but that the anterior tongue was most sensitive to sweet, sour and salty, and least sensitive to bitter. The rear (base) of the tongue was relatively more sensitive to bitter. (Reprinted with permission from Ref 39. Copyright 1942 D. Appleton‐Century Co., Inc.)

[ Normal View | Magnified View ]

Idealized drawing of longitudinal section of a mammalian taste bud. Cells of Types I, II, and III are elongated. These cells have different types of microvilli within the taste pit and may reach the taste pore. Type IV are basal cells and Type V are marginal cells. Classically‐defined synapses occur only between Type III cells and nerve fibers. Many of the connecting taste nerves have myelin sheaths. (Reprinted with permission from Ref 31. Copyright 2005 Marcel Dekker, Inc.)

[ Normal View | Magnified View ]

Features of Type I, II, and III taste cells, including gene expression patterns and functional interactions. Type I cells (blue) degrade or absorb neurotransmitters and may clear extracellular K+ following action potentials (shown as purple bursts) in Type II (yellow) and Type III (green) cells. Salty tastes may be transduced by some Type I cells. Sweet, bitter, and umami tastants activate Type II cells, inducing release of ATP through pannexin1 (Panx1) hemichannels. The extracellular ATP excites ATP receptors (P2X, P2Y) on sensory nerve fibers and on taste cells. Type III cells, in turn, release serotonin (5‐HT), which inhibits receptor cells. Sour tasting stimuli (and carbonation) directly activate Type III cells. Only Type III cells form ultrastructurally identifiable synapses with nerves. (Reprinted with permission from Ref 4. Copyright 2010 The Rockefeller University Press)

[ Normal View | Magnified View ]

Schematic of the key morphological characteristics of Type I (dark), Type II , and Type III taste cells. (Reprinted with permission from Ref 32. Copyright 2005 Oxford University Press)

[ Normal View | Magnified View ]

Browse by Topic

Psychology > Brain Function and Dysfunction

Access to this WIREs title is by subscription only.

Recommend to Your
Librarian Now!

The latest WIREs articles in your inbox

Sign Up for Article Alerts