Neocortical and medial temporal seizures have distinct impacts on brain responsiveness

© 2023 The Authors. Epilepsia published by Wiley Periodicals LLC on behalf of International League Against Epilepsy..

Focal epileptic seizures are characterized by abnormal neuronal discharges that can spread to other cortical areas and interfere with brain activity, thereby altering the patient's experience and behavior. The origin of these pathological neuronal discharges encompasses various mechanisms that converge toward similar clinical manifestations. Recent studies have suggested that medial temporal lobe (MTL) and neocortical (NC) seizures are often underpinned by two characteristic onset patterns, which, respectively, affect and spare synaptic transmission in cortical slices. However, these synaptic alterations and their effects have never been confirmed or studied in intact human brains. To fill this gap, we here evaluate whether responsiveness of MTL and NC are differentially affected by focal seizures, using a unique data set of cortico-cortical evoked potentials (CCEPs) collected during seizures triggered by single-pulse electrical stimulation (SPES). We find that responsiveness is abruptly reduced by the onset of MTL seizures, despite increased spontaneous activity, whereas it is preserved in the case of NC seizures. The present results provide an extreme example of dissociation between responsiveness and activity and show that brain networks are diversely affected by the onset of MTL and NC seizures, thus extending at the whole brain level the evidence of synaptic alteration found in vitro.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:64

Enthalten in:

Epilepsia - 64(2023), 6 vom: 20. Juni, Seite e118-e126

Sprache:

Englisch

Beteiligte Personen:

Russo, Simone [VerfasserIn]
Mikulan, Ezequiel [VerfasserIn]
Zauli, Flavia Maria [VerfasserIn]
Sartori, Ivana [VerfasserIn]
Solbiati, Michela [VerfasserIn]
Furregoni, Giulia [VerfasserIn]
Porro, Marta [VerfasserIn]
Revay, Martina [VerfasserIn]
Rosanova, Mario [VerfasserIn]
David, Olivier [VerfasserIn]
Massimini, Marcello [VerfasserIn]
Tassi, Laura [VerfasserIn]
Pigorini, Andrea [VerfasserIn]

Links:

Volltext

Themen:

Cortico-cortical evoked potential
Effective connectivity
Intracranial recording
Journal Article
Medial temporal lobe epilepsy
Research Support, Non-U.S. Gov't
Responsiveness

Anmerkungen:

Date Completed 05.06.2023

Date Revised 05.06.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1111/epi.17580

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM354995820