Dynamic functional connectivity of the amygdala-hippocampal complex is associated with cognitive impairment in adolescents with Internet gaming disorder.

Background: The amygdala-hippocampal complex (AHC) plays a central role in the neural mechanisms underlying Internet Gaming Disorder (IGD), particularly in emotional regulation, memory processing, and reward-related functions. However, the dynamic interactions between the AHC and large-scale brain networks, and their relationship with cognitive performance in IGD, remain poorly understood. Methods: A total of 123 adolescents (66 with IGD and 57 healthy controls) underwent resting-state functional magnetic resonance imaging (fMRI). Temporal fluctuations in AHC connectivity were assessed using dynamic functional network connectivity (dFNC) analysis. Correlation and mediation analyses were conducted to investigate the relationship between aberrant AHC-related dFNC and cognitive function. Results: Three distinct connectivity states were identified, each characterized by unique network configurations. In State 2, dFNC strength between the AHC and both the attentional network (ATN) and visual network (VN) was positively correlated with T scores of the MATRICS Consensus Cognitive Battery (MCCB). Further mediation analysis revealed that weakened dFNC between the AHC and VN regions, particularly the calcarine sulcus and cuneus, served as a mediator linking cognitive impairment to the internet addiction severity of IGD. Conclusion: These findings suggest that aberrant dynamic connectivity of the AHC, particularly its disrupted interaction with VN, may underlie the cognitive impairments in adolescents with IGD. This study provides novel insights into the neurobiological basis of behavioral addiction and highlights the importance of dynamic network analysis in elucidating its underlying pathology.