Abstract
Sleep disruption is prevalent in secondary and postsecondary students and is associated with learning, affecting regulation, and safety-relevant functioning. Online gaming is a potential contributor because it is inter active, socially and competitively arousing, and often concentrated in the late evening, when screen light exposure and behavioral displacement can shift sleep timing. This review aimed to synthesize student-relevant evidence on online gaming and sleep and well-being while separating three exposure constructs that are often conflated: gaming duration, gaming timing, and problematic gaming or internet gaming disorder (IGD) symptoms. Narrative review using database searches in PubMed/MEDLINE and Google Scholar, followed by backward and forward citation chaining from high-level syntheses. Across student samples, associations were clearer when exposure captured late timing and dysregulated gaming rather than total gaming hours. Timing focused measures (gaming proximal to intended sleep, bedtime displacement, gaming-linked social jetlag) were associated with delayed sleep timing and greater irregularity, with laboratory evidence on evening light exposure supporting circadian delay as a mechanism and experimental protocols indicating sleep effects that depend on game type, duration, and comparator activity. When exposure was defined as problematic gaming or IGD symptom severity, studies more often report poorer subjective sleep quality, insomnia symptoms, daytime sleepiness, and psychological distress, although causal direction remains unclear given heavy reliance on cross-sectional self-report and incomplete confounder control. Neutral or beneficial findings appear context-dependent and were best read as heterogeneity by context and selection rather than as a reversal of the overall association.

Key words: Online gaming, student sleep, well-being, problematic gaming, internet gaming disorder, narrative review