Adapting efficiency of salt-sucrose mixtures

Previous studies had observed that NaCI-sucrose mixtures cross-adapted solutions of their unmixed components just as effectively as adaptation to the components themselves, while quinine-sucrose mixtures were not as effective in cross-adapting their components. The present study investigated whether these effects were due to the different tastants involved or to different conditions of stimulation and adaptation employed. Adaptation to NaCI-sucrose mixtures using the conditions of the quinine-sucrose study resulted in perfect cross-adaptation of NaCI saltiness by the mixture, but only partial adaptation of sucrose sweetness by the mixture. A second study attempted to reconcile this remaining difference by examining the stimulation parameters of flow rate, temperature, and area stimulated. As flow rate and area were decreased, the difference between mixture adaptation and self-adaptation of sucrose was attenuated. Mixture suppression may depend upon the tastants mixed and the parameters of stimulation, and may be the result of several physiological mechanisms.