Abstract
1. The response of the chorda tympani nerve of cats to stimulation of the tongue by NaCl, quinine, HCl, water, saccharine and Ringer's solution was recorded.
2. The magnitude of the integrated response, produced by stimulation of the tongue with Ringer's solution, is increased by increasing or decreasing the temperature of solutions from 30°C, indicating that the nerve conveys impulses to the warming and cooling of the tongue.
3. When NaCl, quinine or HCl solutions of varying concentrations and temperatures were applied to the tongue, the increase in the response magnitude with an increase in the concentration became smaller as the temperature was deviated from 30°C, and the response to taste stimuli alone was found to be greatest at 30°C.
4. Afferent impulses in single chorda tympani nerve fibres were recorded and it was found that nearly all of the units, sensitive to taste, also responded to thermal stimuli.
5. In single units the greatest increase in the impulse frequency with an increase in the concentration of taste stimuli was obtained at 30°C and the impulse frequency did not change appreciably with a change in concentration at 5°, 10° or 45°C.
6. The results indicate that the taste sensitivity to NaCl, quinine and HCl is greatest at 30°C, or at the temperature of the tongue.
