Gustatory Effects of Miraculin, Monellin and Thaumatin in the Saguinus Midas Tamarin Monkey Studied with Electrophysiological and Behavioural Techniques

Abstract

A comparative electrophysiological and behavioral study was made in 17 closely related monkeys of the new world species, S. m. tamarin. The electrical activity in the chorda tympani proper nerve of 2 of the monkeys was recorded during the application to the tongues of 0.02% monellin and thaumatin, 0.5% miraculin and stimuli representing the 4 taste qualities. Monellin and thaumatin gave no or little response, and miraculin enhanced the response to the sour stimulus, but not that to any other taste quality. Behavioral studies were then made with a 2-bottle preference test in 15 monkeys. The animals did not discriminate or discriminated poorly between water and thaumatin or monellin. After miraculin they changed their strong rejection of 0.02 M citric acid, in a choice between water and acid, into a strong preference for the acid. There was a close relation between the electrophysiological and the behavioral data.