Lavoie Suzie, Paquet Jean, Selmaoui Brahim, Rufiange Marianne, Dumont Marie
Chronobiology Laboratory, Hôpital du Sacré-Coeur de Montréal, Québec, Canada.
Chronobiol Int. 2003 Nov;20(6):1019-38. doi: 10.1081/cbi-120025534.
Fourteen healthy subjects (8 women, 6 men, aged 22-35 yr) were recruited. Each subject was exposed, in a counterbalanced order, to bright white light (BWL: 3000 lux) and to dim red light (DRL: <15 lux) at a 1-week interval. Light treatments were administered from 00:30 to 04:30 h during sleep deprivation. Salivary melatonin and urinary cortisol concentrations were measured as was core body temperature. Vigilance levels were evaluated by subjective estimates, maintenance of wakefulness tests (MWT), waking EEG recordings, and three performance tests. Under BWL melatonin secretion was suppressed and core body temperature was significantly higher than under DRL. The BWL and DRL conditions produced no difference in cortisol secretion. Significant effects of BWL treatment were found for the MWT and theta-alpha and beta-1 frequency bands of the waking EEG. There was no significant effect of BWL on subjective alertness and performance. Vigilance measures were similar under the two conditions for the tests performed 1.5 h after the end of light treatments. Overall, the findings suggest that bright light (BL) exposure in the first half of the night decreases EEG-defined sleep propensity but has only modest effects on other aspects of vigilance.
招募了14名健康受试者（8名女性，6名男性，年龄22 - 35岁）。每位受试者以平衡的顺序，每隔1周分别暴露于强光（BWL：3000勒克斯）和暗光（DRL：<15勒克斯）下。在睡眠剥夺期间，于00:30至04:30进行光照处理。测量唾液褪黑素和尿皮质醇浓度以及核心体温。通过主观评估、清醒维持测试（MWT）、清醒脑电图记录和三项性能测试来评估警觉水平。在强光下，褪黑素分泌受到抑制，核心体温显著高于暗光下。强光和暗光条件下皮质醇分泌无差异。发现强光处理对清醒脑电图的MWT以及θ-α和β-1频段有显著影响。强光对主观警觉性和性能无显著影响。在光照处理结束1.5小时后进行的测试中，两种条件下的警觉测量结果相似。总体而言，研究结果表明，夜间前半段暴露于强光会降低脑电图定义的睡眠倾向，但对警觉性的其他方面影响不大。
