The Effects of Lighting on Mental and Cognitive Performance: A Structured Systematic Review

Abstract

Introduction: Lighting affects many non-visual functions such as Circadian rhythm, alertness, core body temperature, hormone secretion and sleep. The aim of this study was to investigate the effects of lighting on human cognitive and mental performance. Methods: In this systematic review, databases including ISI Web of Knowledge, Scopus, PubMed and Science Direct were searched to access the relevant studies. The search was performed using the keywords "Lighting" and "Illumination" and "Cognitive Performance", "Mental Performance", "Memory ", "Attention", and "Concentration" by title, keyword and abstracts of articles published in mentioned databases from 2010 to 2016. Results: Lighting affects human cognitive performance in three areas of psycho-cognitive (visual comfort, visual perception, color recognition, identification of symbols, attention, working memory, learning, reaction time and brain function), biocognitive area (alertness, mood, vitality, subjective feelings, motivation, well-being and quality of sleep) and mental workload (amount of workload, psychological stress, and mental fatigue). The best light to regulate cognitive, biological (circadian rhythm) and mental processes is bright daylight in the morning with a short wavelength (wavelength 420-480 nm) and high intensity (1000lx). Conclusions: Lighting design in addition to providing comfort and visual needs should provide the non-visual and cognitive needs such as attention, alertness, mood, sleep quality and decrease mental fatigue and eventually well-bing.