On the form of psychometric functions for taste

Psychometric functions were determined for the discrimination of weak solutions of quinine hydrochloride or of hydrochloric acid from distilled water. The slopes of these functions were compared with those of some functions previously determined for sodium chloride and for sucrose. In general, the functions for QHCl were the least steep and those for NaCl were the most steep, but the differences were not great. Thus, it appears that the psychometric functions for these different taste qualities have substantially the same form, even though absolute sensitivity varies over several orders of magnitude.