THE EFFECTS OF THE LIGHT WITH DIFFERENT SPECTRAL DISTRIBUTION DURING THE NIGHT-TIME ON MELATONIN SECRETION AND PSYCHOLOGICAL FACTORS IN HUMANS

摘要

This research aimed at confirming the effects of the light with different spectral distribution on melatonin secretion and psychological factors in humans. The participants were exposed to experimental light for two hours (22:00- 24:00).Experimental conditions were, direct 1 control(dim light 50lux) direct 2 6480K in color temperature at 2500lux direct 3 3150K(2500lux) and direct 42740K(2500lux). Saliva was collected before and after the light exposure in order to measure the melatonin concentration. And estimations of psychological factors were done at the same time. Melatonin and psychological factors were statistically analysed, using 1-way ANOVA. Melatonin was significantly different among the four kinds of lighting condition. Melatonin secretion was more suppressed under 6480K and 3150K than 2740K. The scores of Tense Arousal of GACL, Awakening of VAS and Fatigue of VAS were significantly different among the four kinds of lighting condition. Tense Arousal and Awakening were higher after the light exposure under 6480K than control and 2740K. Fatigue was lower after the light exposure under 6480K and 2740K than control.