PURPOSE: To enable accurate evaluation of esthesiophysiological influence by a method wherein an object to be measured is placed into an oral cavity of a vertebrate other than a human being for a fixed time and hourly changes in intensity of reaction of neurocytes among the neurocytes of an animal reacting specifically on a single taste are detected.

CONSTITUTION: An anesthetic such as pontobarbital is administered to a rat and a part of tympanic cord is exposed from the side of a face to keep electrodes 1 and 1 in contact with neurocytes thereof. Then, a sweet substance is bought into contact with a tongue of the rat. As a result, a transmission mechanism of taste stimulation to a living body starts to generate an impulse. The impulse is inputted into an arithmetic means 4 through an amplifier 2 ands a level discrimination means 3 and the results integrated are outputted to a display means 5 as intensity of reaction, Likewise, individual neurocytes reacting specifically to acidity and bitterness are specified. Thus, for example, multiple kinds of drinks and sample solutions are dropped on the tongue of the rat to display changes in the intensity of reaction on sweetness, acidity, bitterness and salty taste of the individual drinks.