Neural trajectories of gaming disorder accounting for psychopathology: Insights from the longitudinal ABCD study.

Gaming disorder (GD) affects approximately 8% of adolescents and is associated with altered reward processing. However, the nature of associations between GD and neural reward systems, and how psychopathology (PP) moderates these associations during development, remains unclear. Using longitudinal data from the Adolescent Brain Cognitive Development (ABCD) Study, we examined 2,046 adolescents (58% female; ages 11-14) at two time points, two years apart. Hierarchical linear mixed-effects models examined bidirectional associations between GD symptoms and neural activation during the Monetary Incentive Delay task, as well as interactions with PP (anxiety, depression, ADHD) across eight reward-circuit regions of interest. After FDR correction and controlling for PP, robust bidirectional associations emerged between GD and reward/loss activation across bilateral amygdala, insula, vmPFC, caudate, putamen, and ACC. A consistent developmental pattern revealed early reward hypoactivation (ages 11-12) transitioning to reward hyperactivation (ages 13-14), suggesting progressive neuroadaptation from reward deficiency to sensitization. Specific types of PP selectively moderated GD × Reward Activation relationships: anxiety and ADHD enhanced the associations between right insula activation and GD symptoms across time. These findings provide further evidence that PP functions as a contributing risk factor of GD, with the right insula emerging as the most robust neural indicator of GD both with and without the effects of PP. Clinically, early treatment of anxiety and ADHD may help minimize GD symptom development during adolescence.