Dynamic excitation/inhibition balance preceding seizure onset and its link to functional and structural brain architecture.

ABSTRACT:

Background

Altered excitation/inhibition (E/I) balance is a key mechanism in epilepsy, but its dynamic changes before seizure onset remain unclear. The interictal suppression hypothesis suggests that inhibitory input isolates epileptic regions, yet little is known about E/I dynamics in the pre-ictal phase.

Methods

We analyzed high-density EEG recordings from patients with drug-resistant focal epilepsy, each with at least one recorded seizure. Cortical activity was reconstructed using source modeling, and time-resolved changes in the aperiodic exponent-a non-invasive marker of E/I balance-were computed. Directed functional connectivity was assessed via spectral Granger causality. These metrics were correlated with cortical thickness and neurotransmitter receptor density maps.

SUBMITTER: Duma GM 

PROVIDER: S-EPMC12581463 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature