Clinical Studies of Gustatory Evoked Response

Abstract

In order to determine whether gustatory evoked response is useful or not as an objective gustometry, the character of the response was researched.
The experiments were carried out in eighteen healthy adults between eighteen and twenty-five years old. Evoked responses were recorded from the temporal region (T₃, T₄) by monopolar method. The trial was repeated twenty times to get a summated evoked response. The taste solutions using deminerized water and tartaric acid solutions were applied to the tongue surface. Also a plastic bar was used as tactile stimuli.
The evoked response was characterized by six peaks. From being recognized in all traces regardless of character of the stimulation the author has deduced the early three peaks caused by tactile sensation. These three peak latencies were approximately 150 msec (N₀), 300 msec (P₁) and 500 msec (N₁) .
The late three peaks found only in response to the tartaric acid were considered as taste res-ponse. These latencies were about 730 msec (P₂), 1300 msec (N₂) and 1600 msec (P₃) . The frequency of their emergence was 75 to 100% in P₂ and N₂.
According to N₂, P₃, a relationship between the latency (T) and stimulus intensity (C) was obtained as the following
T=a log C+K (a, K: constants) .
As a result, the investigation of gustatory evoked response was considered an available method as objective examination.