Medical Psychology & Medical Sociology, University Medical Center of the Johannes Gutenberg - University Mainz, University Medicine Mainz, Duesbergweg 6, 55128, Mainz, Germany.
Department of Psychotherapy and Psychosomatic Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
Appl Psychophysiol Biofeedback. 2023 Sep;48(3):311-321. doi: 10.1007/s10484-023-09581-7. Epub 2023 Mar 27.
Light-induced effects on the autonomic nervous system (ANS) are assumed to be mediated by retinal projections to the hypothalamic suprachiasmatic nucleus (SCN) via different routes. Light information for the circadian system is detected by a subset of intrinsically photosensitive retinal ganglion cells (ipRGCs), however, inconsistency exists in research concerning the effects of light exposure on heart rate variability (HRV). Two within-subject experiments were conducted in a standardized sleep laboratory to investigate effects of light intensity (study I, n = 29: 2 days dim vs. bright light) and spectral composition (study II, n = 24: 3 days using red vs. blue vs. green light) on HRV parameters (RMSSD, LF, HF-HRV, LF/HF ratio). Light exposure was conducted for one-hour in the post-awakening phase at 5:00 AM. Results revealed no significant light intensity effect comparing dim light versus bright white light on HRV parameters. Light color of different wavelengths significantly influenced all HRV parameters except the low frequency, with moderate to large effect sizes. RMSSD values were elevated for all three colors compared to norm values, indicating stronger parasympathetic activation. LED light of different spectral compositions demonstrated bidirectional effects on spectral components of the HRV. Red light decreased the LF/HF ratio within 30 min, whereas with blue light, LF/HF ratio consistently increased across 40 min of light exposure.
光对自主神经系统（ANS）的诱导效应被认为是通过不同途径由视网膜投射到下丘脑视交叉上核（SCN）介导的。光信息为生物钟系统所感知，这是由一部分内在感光视网膜神经节细胞（ipRGCs）完成的，然而，关于光暴露对心率变异性（HRV）的影响的研究结果并不一致。在一个标准化的睡眠实验室中进行了两项个体内实验，旨在研究光强度（研究 I，n=29：2 天暗 vs. 亮）和光谱组成（研究 II，n=24：3 天使用红 vs. 蓝 vs. 绿光）对 HRV 参数（RMSSD、LF、HF-HRV、LF/HF 比）的影响。光暴露在早晨 5 点的觉醒后阶段进行了一个小时。结果表明，与暗白光相比，光强度对 HRV 参数没有显著影响。不同波长的光颜色显著影响所有 HRV 参数，除了低频，具有中等到大的效应大小。与正常值相比，所有三种颜色的 RMSSD 值均升高，表明副交感神经激活增强。不同光谱组成的 LED 光对 HRV 的光谱成分表现出双向影响。红光在 30 分钟内降低 LF/HF 比值，而蓝光则在 40 分钟的光暴露过程中持续增加 LF/HF 比值。
