A difference between morning-type and evening-type on electro-dermal activity, and improvement of sleep phase in evening-type by bright light exposure

我们研究了强光照射对日本大学生相延迟睡眠的改善。首先对369名学生（平均年龄20.6±1.69岁）进行睡眠问卷分析，其中早睡型19人，中间型261人，晚睡型89人。与其他类型相比，夜猫子的开始睡眠时间和起床时间更不规律。夜猫子类型的学生在三种类型中摄入的咖啡因量最大。夜猫子比早猫子有更多的疲劳感和更少的健康感。其次，选取7名身心健康的学生分别在强光照射和不强光照射下进行实验。分别进行多次睡眠潜伏期测试、主观嗜睡量表（Stanford嗜睡量表、Kalolinska嗜睡量表等）。我们通过心率变异性的时间序列数据分析了自主神经系统的指标。主观嗜睡（卡洛林斯卡嗜睡量表）在明亮光线条件下比在室内光线条件下在18点钟时有所下降。在两种光照条件下，自主神经系统指标无显著差异。白天暴露在强光下一天被认为对困倦的影响有限。

We investigated the improvement of phase-delayed sleep inJapanese university students by bright light exposure. First, 369 students (average age20.6±1.69）who were 19 morning type, 261 intermediate type and 89 evening type were analyzed in the sleep questionnaire. Initiating sleep time and wake time was more irregular in evening type than in other types. Evening-type students took the most volume of caffeine in three types. Evening-type students had more fatigue and less feeling of good health compared to morning-type students. Second, seven physical and mental healthy students were participated in the experiments with and without bright light exposure. They were tested Multiple Sleep Latency Test, subjective sleepiness scales (Stanford sleepiness scale, Kalolinska sleepiness scale and so on). We analyzed the indicator of an autonomic nervous system by time series data of heart rate variability. Subjective sleepiness on Kalolinska sleepiness scale was decreased on bright light codition compared to that on room-light condition at 18 o'clock. There were no significant differences on the indicator of an autonomic nervous system in the two light conditions. Bright light exposure during daytime for one day was thought to have the limited effects on sleepiness.