Sex differences in functional connectivity in individuals with internet gaming disorder: a resting-state fMRI Study

Sex differences may help explain the heterogeneity of internet gaming disorder (IGD), but their neural basis remains unclear. This study examined sex-related alterations in functional connectivity (FC) in IGD.

373 participants (85 males with IGD, 62 females with IGD, 141 male recreational game users [RGUs], and 85 female RGUs) underwent resting-state fMRI. The study used a 2 (group: IGD/RGU) × 2 (sex: male/female) between-subjects design. ReHo and FC were analyzed under this design with age as a covariate. ReHo interaction clusters served as seed ROIs for whole-brain FC analyses, followed by simple effect analyses for significant FC interactions.

ReHo showed significant sex-by-group interactions in the bilateral postcentral gyrus, right middle cingulate cortex, and right fusiform gyrus. Seed-based FC showed significant interactions involving these regions. Simple effects indicated that, relative to same-sex RGUs, males with IGD predominantly showed lower FC, whereas females with IGD more often showed higher FC in connections involving perceptual processing, sensorimotor integration, behavioral regulation, self-related processing, and executive control.

IGD-related brain functional abnormalities may exhibit sex differences across multiple inter-regional FC patterns, providing new evidence for the sex-related heterogeneity in IGD. Given the cross-sectional design, these findings reflect associations rather than causal effects.