Vani V, Ojha P, Gadhvi M A, Dixit A
Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India.
Physiol Res. 2025 Jul 25;74(3):519-527.
Light spectra, an imperative zeitgeber, may differ in its chronobiological effects among chronotype ensuing differences in circadian pacesetting. With the increasing usage of colored lights in the environment, the effects of light wavelength on the electrical activity of the brain among chronotypes need to be investigated. Healthy participants (N=24) were recruited to morning, intermediate, and evening chronotype groups using the composite scale for morningness scores. They were exposed to randomized brief sessions of red, green, blue, and white light preceded by 15 min of darkness. EEG was recorded in all sessions. The power spectrum was estimated for alpha, beta, theta, and delta waves from different regions of the scalp and compared among the groups. The morning and evening chronotype had statistically significantly higher mean delta power than intermediate chronotype in colored light. Evening chronotype showed a statistically significantly higher mean beta power than the intermediate chronotype (p=0.013) in green light. Intermediate chronotype had statistically significantly higher mean alpha power than morning (p=0.029) and evening chronotype (p=0.009) in red light. The results show a significant effect of the spectral property of light on brain waves in chronotypes. The green light is more effective in alerting evening chronotypes. The finding of the present study may be applicable in research pertinent to brain imaging in chronotypes especially with red, green, and blue light exposure and chromotherapy-based interventions in affective and psychiatric conditions. Key words Circadian rhythm " Color of light " Light and chronotype " Wavelength of light " EEG in chronotypes.
光谱作为一种至关重要的时间线索，其在昼夜节律调节方面的生物学效应可能因昼夜类型不同而有所差异。随着环境中彩色灯光使用的增加，光波长对不同昼夜类型人群大脑电活动的影响有待研究。我们使用晨型得分综合量表，将24名健康参与者分为晨型、中间型和夜型三组。让他们在黑暗15分钟后，随机接受红、绿、蓝和白光的短暂照射。所有照射过程均记录脑电图。估算头皮不同区域的α、β、θ和δ波的功率谱，并在各组之间进行比较。在彩色光照射下，晨型和夜型的平均δ波功率在统计学上显著高于中间型。在绿光照射下，夜型的平均β波功率在统计学上显著高于中间型（p = 0.013）。在红光照射下，中间型的平均α波功率在统计学上显著高于晨型（p = 0.029）和夜型（p = 0.009）。结果表明，光的光谱特性对不同昼夜类型的脑电波有显著影响。绿光在唤醒夜型人群方面更有效。本研究结果可能适用于与不同昼夜类型脑成像相关的研究，特别是在涉及红、绿、蓝光照射以及基于色光疗法的情感和精神疾病干预方面。关键词：昼夜节律；光的颜色；光与昼夜类型；光的波长；不同昼夜类型的脑电图
