Department of Psychosocial Science, University of Bergen, Bergen, Norway.
Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway.
Chronobiol Int. 2022 Jul;39(7):948-963. doi: 10.1080/07420528.2022.2050922. Epub 2022 Mar 28.
Night work leads to sleepiness and reduced vigilant attention during work hours, and bright light interventions may reduce such effects. It is also known that total sleep deprivation impairs cognitive flexibility as measured by reversal learning tasks. Whether night work impairs reversal learning task performance or if bright light can mitigate reversal learning deficits during night work is unclear. In this counterbalanced crossover study (ClinicaTrials.gov Identifier NCT03203538), young healthy individuals completed a reversal learning task twice during each of three consecutive simulated night shifts (23:00-07:00 h). The night shifts were performed in a laboratory under a full-spectrum (4000 K) bright light (900 lx) and a standard light (90 lx) condition. Reversal learning task performance was reduced towards the end of the night shifts (04:50 h), compared to the first part of the night shifts (00:20 h) in both light conditions. However, with bright light, the reversal learning task performance improved towards the end of the night shifts, compared to standard light. The study shows that bright light may mitigate performance deficits on a reversal learning task during night work and implies that bright light interventions during night work may be beneficial not only for vigilant attention but also for cognitive flexibility.
夜班导致工作时间困倦和警觉注意力降低，而明亮的光线干预可能会减少这些影响。众所周知，完全睡眠剥夺会损害认知灵活性，这可以通过反转学习任务来衡量。夜班是否会损害反转学习任务的表现，或者明亮的光线是否可以减轻夜班期间的反转学习缺陷，目前尚不清楚。在这项平衡交叉研究（ClinicalTrials.gov 标识符 NCT03203538）中，年轻健康的个体在连续三个模拟夜班（23:00-07:00 小时）中的每一次夜班期间都完成了两次反转学习任务。夜班在全光谱（4000 K）明亮光线（900 lx）和标准光线（90 lx）条件下在实验室中进行。与夜班开始时（00:20 小时）相比，在两种光线条件下，反转学习任务的表现都在夜班接近尾声时（04:50 小时）下降。然而，在明亮的光线下，与标准光相比，反转学习任务的表现会在夜班接近尾声时提高。该研究表明，明亮的光线可能会减轻夜班期间反转学习任务的表现缺陷，并暗示夜班期间明亮的光线干预不仅对警觉注意力有益，而且对认知灵活性也有益。
