Altered brain activity mediates the correlation between childhood trauma and aggression in youths with internet gaming disorder

Childhood trauma is a recognized risk factor for affective dysregulation and aggressive behavior in adolescents with Internet Gaming Disorder (IGD). However, the neurobiological pathways linking trauma to aggression in IGD remain poorly understood. This study aims to investigate how childhood trauma affects aggressive behavior in adolescents with IGD through specific neurobiological mechanisms. We recruited 111 adolescents categorized into IGD with childhood trauma (IGD-CT, n = 43), IGD without trauma (IGD N, n = 31), and healthy controls (HC, n = 37). Using resting-state fMRI, we computed amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF) to compare spontaneous brain activity. Then we correlated the regional ALFF/fALFF with levels of childhood trauma (CTQ-SF score) and aggression. Finally, we conducted a mediation analysis to examine whether brain activity modulates the relationship between childhood trauma and aggression in youths with IGD. The IGD-N group showed significantly lower fALFF compared with the IGD-CT group，they also had significant differences compared to the HC group. Furthermore, the mean fALFF in the left precuneus was positively correlated with CTQ-SF ( r = 0.321, p = 0.008) and reactive aggression (RA; r = 0.396, p = 0.001) scores. Importantly, the mean fALFF in the left precuneus partially mediated the correlation between CTQ-SF and RA scores (effect proportion of 28.18 %). Our study identifies the left precuneus as a critical neural region where childhood trauma uniquely impacts aggression in adolescents with IGD. The findings highlight the necessity for targeted interventions in IGD with trauma histories, providing potential avenues to reduce aggression in at-risk adolescents affected by both trauma and gaming addiction. • This study is the first to use fMRI to explore how childhood trauma affects aggression within the context of Internet Gaming Disorder (IGD) in adolescents. • Identifies the left precuneus as a neural hub where childhood trauma uniquely impacts emotional reactivity. • Provides mechanistic evidence supporting the "trauma-emotion dysregulation-aggression" model, relevant to affective disorder comorbidity. • Significant correlations were found between neural activity, reactive aggression, and childhood trauma, indicating that early adverse experiences may impact emotional regulation and increase vulnerability to aggressive behavior. • Findings suggest the need for targeted therapeutic interventions to improve emotional regulation skills in adolescents with a history of childhood trauma, particularly in those with IGD.