The Influence of Intensity and Timing of Daily Light Exposure on Subjective and Objective Sleep in Adolescents with an Evening Circadian Preference

Abstract Study Objectives The aim of the present study is to examine the relationship between light and sleep, in adolescents with an evening circadian preference. Methods For a period of seven days, ninety-nine adolescents wore a wrist actigraph to assess light exposure and objective sleep and completed a sleep diary to assess subjective sleep. Results Lower average light intensity across the preceding 24 hours was associated with a later sleep onset (p Conclusion This study highlights the importance of light exposure, particularly the timing of light exposure, for establishing healthy patterns of sleep among adolescents with a propensity for a delayed bedtime and waketime. These findings provide additional evidence for targeting light exposure when designing interventions to improve adolescent sleep.