抄録
The aim of the present study was to determine the measurement dependence of the effects of color light and
to clarify the correlation between physiological responses and subjective impression. Seventeen male university
students without color vision deficiency were exposed to blue light and red light (200 lx at eye level) at night for
three hours. The effects of blue light on pupil constriction and melatonin suppression were significantly greater than
the effects of red light. On the other hand, heart rate tended to be higher under the red light condition. There was
no significant difference between the effects of blue light and red light on rectal temperature or alertness. Individual
variations in the subjective impression of light were correlated with heart rate and rectal temperature but not with
melatonin concentration or pupil constriction. The results suggest that the physiological effects of light depend on
measurements and that these variations may be influenced by subjective impression.
