舌電気刺激による誘発電位に関する研究

Abstract

Strong and weak electric stimulations were applied to the tongues and buccal mucosae of twelve normal male adults to measure the cerebral evoked potential (CEP) and to qualitatively analyze the relationship between subjective sensitivity and the late component of CEP. The following conclusions were obtained.1) In the CEP noted 50 to 300 msec after stimulation, four-phase waves (N1, P1, N2, and P2) were observed in all subjects. These were components of the somatosensory evoked potential (SEP).2) In the SEP caused by electrical stimulation of the tongue, increased electric was associated with a significant increase in the amplitude between N2 and P2 (P<0.001). At peak latency, no significant difference was noted, similar to the SEP caused by electric stimulation of the buccal mucosa conducted as control.3) Even with the same electric current, no significant difference was noted at peak latency of the SEP when electric stimulation was applied to the tongue and buccal mucosa, but highly significant differences were recognized for each amplitude (P<0.001). These results suggested that current-related variations in wave components could be examined only for SEP having the same site of stimulation.4) In CEP caused by electric stimulation to the tongue, N100, which was a unique negative component, was recognized about 100 msec after stimulation between N1 and P1 of SEP only at the gustatory evoked potential (GEP) when electric taste was induced in the subjects. N100 reflected the information process of taste acceptance and transmission and was suggested to be a component related to the process of selecting taste quality.5) N100 of GEP was suggested to have the potential for objective quantification of taste.