Rapid Estimation of Gustatory Sensitivity Thresholds.

The ability to taste enables detection of nutrients and toxins in the oral cavity and is therefore a crucial determinant for decisions as to whether to consume or reject a food. The assessment of taste function is pertinent to identify selective (for one taste) or generalized (for all tastes) taste impairment, as it may lead to deviant eating behavior and malnutrition. Sensory sensitivity is a good measure of the overall function of a sensory system. It can be most efficiently assessed with adaptive algorithms that have been, however, methods (QUEST, SIAM, quickYes-No) to rapidly estimate taste thresholds for 4 basic taste qualities in a yes-no-task. We compared thresholds obtained with QUEST and SIAM (study 1) and QUEST and quickYes-No (study 2) using within-subject test-retest designs and assessed further QUEST thresholds (studies 3 and 4) resulting in an overall sample of N=163. Tastants were dilutions series of aqueous solutions of sodium chloride, quinine, sucrose, and citric acid presented via spray bottles to anterior taste bud fields. We found that gustatory thresholds can be obtained fastest with QUEST (Mean 6.5 min). All methods yield acceptable (SIAM) to good (quickYes-no, QUEST) test-retest correlations (0.4–0.8). Thresholds were highly correlated between QUEST and quickYes-No (r>0.63) indicating that the procedures measure similar perceptual properties. Notably, quickYes-No can detect fluctuations of the response criterion (at the expense of testing time). Our data indicate, however, that participants were able to maintain a relatively stable criterion even in QUEST through instructions alone. Together, the findings suggest that adaptive methods are suitable for the quick and reliable measurement of gustatory sensitivity