Galvanic vestibular stimulation induces virtual acceleration sensation and is expected to be applied in computer games to improve their reality. The acceleration sensation can be enhanced by giving countercurrent which consists of an opposite current part and a forwarding current part. Conventionally, however, the degree of the enhancement is uncontrollable. This study reports that the effect of countercurrent can be modeled by an electrical circuit containing a capacitor and resistors. To model the effect of the countercurrent on the acceleration perception, we investigated the relation between the parameters: the duration and the strength of the opposite current part, of the countercurrent and strength of acceleration perception. The results of our study show that the strength of the acceleration sensation induced by the countercurrent stimulation has a nonlinear correlation with the duration of the opposite current, and the characteristics of the enhancement effect can be estimated using a CR circuit model.

The mechanism by which cathodal current stimulation exerts inhibitory effects on the five basic tastes is revealed herein. The objective of this paper is to successfully achieve inhibition of sweetness by cathodal current electrical stimulation to the tongue, which has not been reported to date, though inhibition of salty and umami perception has been documented. By focusing on the electrophoresis of ions generated by dissolution of taste-inducing substances in water, this paper indicates how human gustation is inhibited by electrical stimulation, which is a key addition to the knowledgebase for achieving control of all five basic tastes.