Effects of progressive aerobic training on neural synchrony and functional connectivity in internet gaming disorder: A randomized controlled fMRI study

Background Internet gaming disorder (IGD) has gained increasing attention due to its rising global prevalence, with significant negative impacts on mental health, academic performance, and social functioning. Aerobic exercise, due to its low cost and high adherence, has emerged as a potential intervention. This study aimed to examine the behavioral and neural effects of a moderate-intensity, progressive aerobic exercise program in individuals with IGD. Methods Eighty college students with IGD were randomly assigned to a progressive aerobic training group (PAT) or a free training group (FT), with 68 completing the study. The PAT group engaged in 20 supervised treadmill sessions over four weeks, with intensity progressively increasing from 46–55% VO₂max. The FT group exercised freely without restrictions. Behavioral assessments (IAT, DSM-5 IGD scale, QGU) and fMRI scans were conducted before and after the intervention. Neural synchrony was assessed using inter-subject correlation (ISC) analysis, and seed-based connectivity (SBC) analysis was performed to examine changes in functional connectivity of addiction-related brain regions. Results The PAT group showed significant reductions in IAT and DSM-5 scores, with a notable group × time interaction for IAT. fMRI results revealed increased ISC in the left postcentral gyrus and decreased ISC in the left caudate and right precentral gyrus. Caudate ISC changes correlated with IAT improvements. SBC analysis showed reduced connectivity between the left caudate and right prefrontal cortex in the PAT group. Conclusions Progressive moderate aerobic exercise reduced IGD symptoms and craving, alongside altered neural synchrony and connectivity in reward and control networks. Caudate-related markers may serve as potential targets for intervention. Future studies should adopt larger, longitudinal designs.