Impact of Daily Screen and Social Media Time on REM Sleep in Adolescents

Adolescents average more than seven hours of daily screen time, yet most do not get the recommended amount of nightly sleep, with consequences for mental health and performance. The specific association of screen and social media use with REM sleep, which is important for memory consolidation and emotional processing, remains underexplored. This quantitative, longitudinal, correlational pilot study passively collected consecutive-day data from 5 adolescent cross-country athletes (ages 15 to 18; N=90 participant-nights) using Garmin smartwatches (wrist-based sleep and REM estimation) and Apple Screen Time (total and social media usage). Composite data showed a mean daily screen time of 6.0 hours (2.6 hours social media), mean sleep of 7.0 hours, and mean REM of 1.6 hours (22% of sleep). Pearson correlations between screen time and sleep outcomes were small and not statistically significant: total sleep (r=0.07, p=0.54), REM minutes (r=0.11, p=0.29), and %REM (r=0.14, p=0.20); social media correlations were similarly small (r=0.01 to 0.07, all p>0.05). Neither the primary hypothesis, a statistically significant negative correlation between screen time and REM sleep, nor the secondary hypothesis, a statistically significant negative correlation between social media usage and sleep, was supported. However, 95.2% of REM deficits required at least three nights to recover, with a mean of 5 to 7 nights, consistent with the tertiary hypothesis that recovery from a REM deficit takes three or more nights. These null findings may reflect limited statistical power (N=90 was powered only for large effects, r≥0.29), the non-independence of repeated nights from the same participants, and numerous unmeasured confounders. Future research with larger samples (approaching N=1000) and polysomnography is warranted to clarify the relationship between digital media use and adolescent sleep architecture.