Association of Screen Time with Attention-Deficit/Hyperactivity Disorder Symptoms and Their Development: The Mediating Role of Brain Structure

Objective The effect of screen time on the development of attention-deficit/hyperactivity disorder (ADHD) symptoms, as well as the brain, and neural mechanisms underlying the association between screen time and ADHD symptoms remain unclear. This study aims to examine the association between screen time, ADHD symptoms, and the brain, using large-scale longitudinal samples from the Adolescent Brain Cognitive Development (ABCD) study. Method From the ABCD study, we extracted, data on screen time, ADHD symptoms based on the Child Behavior Checklist, and brain structure measures of 10116 and 7880 children (aged 9–10 years) at baseline and at the 2-year follow-up, respectively. We used the linear mixed-effects model to examine the association between screen time at baseline, and the development of ADHD symptoms and brain structure after two years. We also examined the mediating role of brain structure on the association between screen time and ADHD symptoms. Results Screen time was associated with the development of ADHD symptoms (β = 0.032, p  = 0.001) and thickness of some cortical regions (right temporal pole: β=-0.036, false discovery rate (FDR)-corrected p  = 0.020; left superior frontal gyrus: β=-0.028, FDR-corrected p  = 0.020; and left rostral middle frontal gyrus: β=-0.030, FDR-corrected p  = 0.020). Moreover, the total cortical volume partially mediated the relationship between screen time and ADHD symptoms (β = 0.001, p  = 0.023) at baseline. Conclusion These results suggest that screen time influences ADHD symptom development and brain structure, providing insight into the mechanisms underlying the association between screen time and ADHD symptoms. Furthermore, interventions to reduce screen time may help improve ADHD symptoms.