Correlation Between Screen Time, Sleep Duration, and Stroop Effect Among First-Year Osteopathic Medical Students: A...

The Stroop test is a well‑validated measure of selective attention and inhibitory control. Although increased electronic device use has been consistently associated with shorter sleep duration and delayed bedtime, whether everyday variability in screen time and sleep relates to Stroop performance in medical trainees remains uncertain, and existing findings on executive function are mixed.

This study aimed to examine associations between average daily screen time, self‑reported sleep duration (past week and past month), and Stroop performance measured using the EncephalApp (congruent reaction time, incongruent reaction time, and Stroop interference) in first-year osteopathic medical students.

In this cross‑sectional study conducted between March and July 2025, 69 first‑year osteopathic medical students were recruited, of whom 49 (10 male, 39 female) provided complete datasets. Participants completed the EncephalApp Stroop test on their smartphone and an anonymous survey reporting demographic characteristics, average daily screen time over the past week, and sleep duration over the past week and past month. Simple linear regression analyses were used to examine associations between Stroop interference and screen time, Stroop interference and sleep duration, and between screen time and sleep duration.

Participants (n = 49; 10 male, 39 female) had a mean age of 25.61 ± 3.58 years. The mean congruent reaction time (OffTime) was 54.06 ± 10.06 seconds, the incongruent reaction time (OnTime) was 60.94 ± 13.59 seconds, and the mean Stroop interference score was 6.87 ± 7.38 seconds. The average daily screen time over the past week was 6.10 ± 3.12 hours, while the average sleep duration was 6.93 ± 1.26 hours over the past week and 7.04 ± 1.16 hours over the past month. Stroop interference was not significantly associated with screen time (R² = 0.0023; p = 0.746) or sleep duration (past week: R² = 0.0287; p = 0.250; past month: R² = 0.0303; p = 0.237). However, screen time was inversely associated with sleep duration over the past week (R² = 0.14; β = -0.152 hours of sleep per additional hour of screen time; p = 0.0088).

Among first-year osteopathic medical students, typical variation in screen time and sleep duration was not associated with Stroop‑indexed selective attention. Higher screen time was, however, moderately associated with shorter sleep duration. These findings are consistent with prior evidence linking electronic media use to reduced sleep and suggest that modest between‑person differences in sleep and screen exposure may not translate into measurable differences in Stroop performance in this population.