Panarese Alessandro, Vissani Matteo, Meneghetti Nicolò, Vannini Eleonora, Cracchiolo Marina, Micera Silvestro, Caleo Matteo, Mazzoni Alberto, Restani Laura
The Biorobotics Institute, Scuola Superiore Sant'Anna, viale Rinaldo Piaggio 34, 56025 Pontedera, Italy.
Department of Excellence in Robotics and Artificial Intelligence, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà, 56127 Pisa, Italy.
Cereb Cortex. 2023 Mar 21;33(7):4173-4187. doi: 10.1093/cercor/bhac335.
The epileptic brain is the result of a sequence of events transforming normal neuronal populations into hyperexcitable networks supporting recurrent seizure generation. These modifications are known to induce fundamental alterations of circuit function and, ultimately, of behavior. However, how hyperexcitability affects information processing in cortical sensory circuits is not yet fully understood. Here, we investigated interlaminar alterations in sensory processing of the visual cortex in a mouse model of focal epilepsy. We found three main circuit dynamics alterations in epileptic mice: (i) a spreading of visual contrast-driven gamma modulation across layers, (ii) an increase in firing rate that is layer-unspecific for excitatory units and localized in infragranular layers for inhibitory neurons, and (iii) a strong and contrast-dependent locking of firing units to network activity. Altogether, our data show that epileptic circuits display a functional disruption of layer-specific organization of visual sensory processing, which could account for visual dysfunction observed in epileptic subjects. Understanding these mechanisms paves the way to circuital therapeutic interventions for epilepsy.
