부산대학교 도서관

The vestibulo-ocular reflex (VOR), which is a reflexive eye movement generated in the opposite direction of head movement, is affected by volition of the head movement; it indicates the activeness or passiveness of the head movement. Research has yet to reveal the effect of actively operating or passively riding on a vehicle on a human's VOR. Therefore, in this study, we investigate the influence of the presence / absence of the operation of such a mechanical system moving in the pitch direction, as well as the frequency of operation, on VOR gain. Twelve subjects without disease in the vestibular system participated in the experiment. Experimental factors were the volition of operation, which includes active and passive, and the frequency of the operation, which includes 0.5, 1.0, and 1.5 Hz. They were set as the within-subject design. Subjects riding a vehicle are instructed to fixate on a target while the vehicle reciprocates in the pitch direction, as controlled by a joystick. The angular velocity of the eye, as well as the angular velocity and acceleration of the head and of the vehicle are measured. The experimental results show that VOR gain significantly increases in the active condition for operating frequencies of 0.5 Hz and 1.0 Hz. The measured data are analyzed using a computational VOR model previously proposed by the authors; these results suggest that differences in the volition of vehicle operation appear in the model parameters, which represent the accuracy of self-motion perception.