Experimental Effects of Light And Content From Evening Screen Media Use On Children's Sleep, Executive Functioning, And Emotion Regulation

What this Trial Is About

Researchers are investigating how evening exposure to light from tablet devices and the type of media content shown affect children's sleep, internal body clocks, emotion control, and thinking skills. The study focuses on children aged 8 to 11 years at early stages of puberty (Tanner stage 1 or 2). This randomized controlled trial aims to separate the effects of screen brightness and exciting versus calming content on these outcomes. The study includes 200 children randomly assigned to one of four groups combining bright or dim tablet screen light with either exciting or calming content. Each child will participate in two weekend protocols at home, one with screen use for one hour before bed under their assigned condition, and one with quiet, non-screen activities serving as a control. The order of these weekends is randomized to reduce order effects. Researchers will control bedroom lighting and measure melatonin levels to assess shifts in circadian timing. Sleep will be monitored using wrist activity trackers, heart rate sensors, and subjective sleepiness ratings. During the study, children will maintain a consistent sleep schedule set by their parents. Research staff will visit homes to collect saliva samples for melatonin measurement and conduct tests on emotion regulation and executive function the afternoon after each weekend. The study will track sleep duration, quality, heart rate, arousal, and cognitive performance to understand how evening screen exposure impacts children's sleep and next-day functioning. The total study participation lasts about two weeks with assessments on specific nights and days.

SCREENS: Sleep, Circadian Rhythms, and Electronics in the EveNing Study