2010 年 8 巻 2 号 p. 43-49
We investigated the effects on visual evoked potential (VEP) of stimulus configuration, interval and duration of visual stimulation using a shutter-goggle. Subjects were 13 healthy young adults. We used a vertical stripe image as the visual stimulus, which was induced by opening the shutter. The stimulus conditions were set as follows: the stripe width at 1-degree increments from 1- to 8-degree, the stimulation duration at 10-ms increments from 20- to 60-ms, and the stimulation interval at 200-ms increments from 400- to 2000-ms. In the VEP, a positive peak component (P100) was detected at 70-130 ms after shutter opening onset. P100 amplitude was significantly larger for 1- and 2-degree widths than for the other widths. The amplitude showed no significant difference between 1- and 2-degree widths, and gradually decreased from 3- to 8-degree. The amplitude was significantly smaller for 20-ms duration than for the other durations, and showed no significant difference among durations from 30- to 60-ms. The amplitude was significantly smaller for the 600-ms interval than for larger intervals, and showed no significant difference among intervals from 1000- to 2000-ms.
