Twenty-eight IGE patients (15 valproate, 13 levetiracetam) and 19 controls were included in this study. The properties of resting-state networks were evaluated by coherence of EEG data in each of drug-naïve status and follow-up periods. Graph theoretical analyses were performed, and global efficiency and local efficiency were compared between IGE patients and controls in both drug-naïve status and follow-up periods.

Global efficiency was increased in delta and gamma bands in patients with drug-naïve IGE relative to controls, and increased in delta, theta, beta, and gamma bands in IGE patients of follow-up periods relative to controls. In all frequency bands except alpha band, local efficiency was increased in drug-naïve IGE patients relative to controls and increased in IGE patients of follow-up periods relative to controls. There was no difference between IGE patients using valproate and using levetiracetam (FDR-corrected p < 0.05).

We observed that the property of cerebral network was changed toward an efficient topology even in drug-naïve IGE patients and no differences between the types of antiepileptic drugs, suggesting the aberrant network topology might be related to pathophysiological mechanisms underlying IGE rather than the effects of antiepileptic drugs. We speculate that the aberrant cerebral network toward efficient topology might be associated with facilitating synchronization and generation of generalized spike and wave discharges in IGE.