Abstract
The human brain wave induced by flickering lights (Visual Evoked Potential: VEP) was investigated for the possible application to a special GUI system. The flickering frequency of 8-12Hz was found to elicit large VEP amplitudes when the stimulating LED was being gazed at. Shifting the fixation point reduced the VEP amplitude, e. g., about 50% reduction by 2.5 degree shift. The study was extended for the situation of multiple LED sources. When the flickering frequencies were all different in the range of 8-12Hz, the VEP frequency component corresponding to the fixation LED produced the largest amplitude. When the frequencies were the same but there were phase (timing) differences, it was also possible to tell, by the VEP phase comparison, which LED was being gazed at. These results seem to suggest the feasibility of using VEP for the handicapped to select GUI icons displayed on a CRT monitor.
