Temporal tuning of illuminance and spectrum: Effect of a full-day dynamic lighting pattern on well-being, performance and sleep in simulated office environment

Abstract

Dynamic lighting is a potentially promising solution to meet the individual's chronobiologic and psychological needs at specific times of day or for specific activities. Yet, few studies have investigated the impact of dynamic lighting patterns on daytime functioning and nocturnal sleep, and the optimal dynamic lighting pattern remains largely unknown. The current study assessed the effects of a daylong dynamic lighting (DL) pattern with modulations in intensity and spectrum vs. static office lighting (SL) on markers of well-being, cognitive performance, visual experiences, and sleep in a simulated office environment. Twenty-one subjects participated in the 48-h balanced crossover laboratory study. The findings revealed time-of-day and experimental-day dependent benefits of the DL vs. SL pattern on daytime vitality, sleepiness, state self-control, mood, performance on a sustained attention task and subsequent subjective sleep quality. Complementing earlier research outcomes reported in the literature, the current study suggests that a dynamic lighting approach could be a practical strategy to support office workers' daytime well-being and nocturnal sleep. Yet, the results revealed no consistent pattern across assessments nor across the different types of metrics at a specific assessment, thus additional research regarding the optimization of lighting parameters and pattern is needed.