Gustatory adaptation to saliva and sodium chloride.

Abstract

Human NaCl thresholds were measured under 2 conditions: salivary influence excluded by rinse with distilled water or 1 of 3 weak concentrations of NaCl between stimulations, and salivary influence maximized by using no rinse. Adaptation to distilled water yielded a median threshold for 4 Ss of .00014[image] vs. .0043 [image] for adaptation to saliva. The latter value approximated the resting concentration of sodium in the saliva of these Ss. Adaptation to saline solutions raised the thresholds to values slightly above each of the adapting concentrations. It is concluded that salt thresholds normally reflect the state of adaptation to salivary sodium. Changes in general physiological state of the organism which affect salivary composition might be expected to shift the taste threshold by a process of sensory adaptation.