Qian Liu, Ru Taotao, Chen Qingwei, Li Yun, Zhou Ying, Zhou Guofu
Lab of Light and Physio-psychological Health, School of Psychology, South China Normal University, Guangzhou, China.
National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, China.
J Sleep Res. 2021 Aug;30(4):e13242. doi: 10.1111/jsr.13242. Epub 2020 Nov 30.
Previous research revealed inconsistent effects of bright light or a short nap at noon on alertness and performance across different tasks. The current study aimed to explore whether the effects of bright light and a short nap at noon on task performance depended on the cognitive domain. Bright light (1,200 lx, 4,000 K at eye level), nap (near darkness) and control (200 lx, 4,000 K at eye level) conditions were performed from 1:00 to 1:40 PM on three non-consecutive days with a counterbalanced order across participants. After being assigned to one of three conditions, participants underwent two repeated test sessions, each including a psychomotor vigilance task, a go/no-go task, and a paced visual serial addition task, with an interval of more than 1 h, to assess the persistent effects of napping and bright light. Subjective sleepiness, vitality, self-control and mood were also measured. Results showed that accuracy on the go/no-go task and the paced visual serial addition task improved significantly throughout the entire experiment session after napping, whereas reaction speed on the paced visual serial addition task improved time-dependently in the bright light intervention, with a higher reaction speed in only the first test session. Nearly all subjective states benefited from napping but not from bright light. These findings suggested that the effects of bright light and an afternoon nap on task performance would depend on the cognitive domain. An afternoon nap may elicit more effective and persistent benefits on task performance and subjective states.
先前的研究表明，强光或中午小睡对不同任务中的警觉性和表现的影响并不一致。当前的研究旨在探讨中午强光和小睡对任务表现的影响是否取决于认知领域。在三个不连续的日子里，于下午1点至1点40分进行强光（1200勒克斯，眼睛水平处色温4000K）、小睡（接近黑暗环境）和对照（200勒克斯，眼睛水平处色温4000K）条件，参与者采用平衡顺序。被分配到三种条件之一后，参与者进行了两个重复测试环节，每个环节包括一项心理运动警觉任务、一项停止信号任务和一项视觉序列加法任务，间隔超过1小时，以评估小睡和强光的持续影响。还测量了主观嗜睡、活力、自我控制和情绪。结果显示，小睡后，在整个实验环节中，停止信号任务和视觉序列加法任务的准确性显著提高，而在强光干预下，视觉序列加法任务的反应速度随时间改善，仅在第一个测试环节中反应速度更高。几乎所有主观状态都从小睡中受益，而非强光。这些发现表明，强光和午睡对任务表现的影响将取决于认知领域。午睡可能会对任务表现和主观状态产生更有效和持久的益处。
