Evaluation of the Effect of Visual Stimulation on Humans by Simultaneous Experiment with Multiple Subjects

To evaluate the biological effects of visual stimulation on multiple subjects watching a same image, a more compact and low-cost device measuring both ECG and photo-plethysmogram was developed. On the basis of these physiological parameters, the maximum cross-correlation coefficient, rho
_max
, from pulse wave transmission time to heart rate could be calculated. This index reflects the activity of the autonomic nervous system and is considered as a good index for evaluating the effect of visual stimulation on humans. The result of simultaneous experiment with 6 subjects watching a video image taken by an intentionally swaying handy camera has shown that rho
_max
of almost all subjects decreased in the latter part of the video image and that rho
_max
of the subjects who felt motion sickness strongly decreased after watching the video image at a time