Small groups influence large networks

Abstract

Epilepsy How small groups of neurons can interact with large networks in the brain is a crucial question in epilepsy research. Eissa et al. analyzed multielectrode array recordings from epileptic patients and found that during seizures, local action-potential activity organized into tiny wave fronts that correlated with network activity on scales that were orders of magnitude larger. These correlations did not exist between seizures or in neuronal activity outside the wave front. Computational modeling revealed an antagonistic role for feedforward inhibition. At the local level, inhibition failed, which permitted the wave front to propagate. In contrast, at a much larger scale, feedforward inhibition created the conditions for the seizure to cease after the wave front had vanished. Proc. Natl. Acad. Sci. U.S.A. 10.1073/pnas.1702490114 (2017).