Increase in EEG functional connectivity and power during wakefulness in self-limited epilepsy with centrotemporal spikes.

OBJECTIVE

Examine power and functional connectivity (FC) in children with Self-limited Epilepsy with Centrotemporal Spikes (SeLECTS) during resting-state.

METHODS

We retrospectively analyzed 37 children with SeLECTS and 34 matched controls. Fifty seconds of awake resting-state source-reconstructed EEG per subject were selected to compare groups using power and weighted phase lag index (wPLI). We compared patients' epochs with and without interictal epileptiform discharges (IEDs) between each other and to controls' epochs. Additionally, we compared epochs without IEDs from recent-onset SeLECTS and longer-duration SeLECTS patients between each other and to controls' epochs.

RESULTS

SeLECTS patients demonstrated widespread and significant power increases compared to controls. FC analyses of epochs without IEDs revealed predominantly left-sided increases in the beta band and decreases in theta band compared to controls. In epochs with IEDs, there were further FC increases in the delta band compared to epochs without IEDs located in bilateral fronto-centrotemporal regions. Patients with recent-onset SeLECTS had significant bilateral temporo-parietal FC increases in beta1 relative to controls. Patients with longer-duration SeLECTS showed significant left centrotemporal FC increases in beta and bilateral centrotemporal decreases in delta compared to controls.

CONCLUSIONS

SeLECTS patients exhibit atypical power and FC patterns during wakefulness, even in epochs without IEDs. These were more pronounced in recent-onset cases and epochs with IEDs, suggesting an association between IEDs frequency and the disease course.

SIGNIFICANCE: Studying power and FC abnormalities in children with SeLECTS provides insight into disease evolution and the influence of IEDs on brain networks.