Default mode network hub disruption links problematic use of the Internet to brain network disorganization.
Comprehensive Psychiatry July 1, 2026 Nagara Takao, Naoya Oishi, Qi Dai et al.
Problematic use of the internet (PUI) is linked to altered brain network organization through its effect on the default mode network (DMN). In 190 healthy adults aged 20–69, higher PUI severity correlated with reduced functional connectivity among DMN regions. This reduced DMN connectivity strongly predicted changes in whole-brain network properties, including decreased clustering and local efficiency, and increased global efficiency and shorter path lengths—indicating a shift away from optimal small-world network organization. Mediation analyses showed that DMN connectivity substantially mediated the relationship between PUI severity and these network metrics, suggesting that DMN hub disruption is a key pathway by which PUI affects global brain network topology.