Journal article
Increased neuronal synchrony prepares mesial temporal networks for seizures of neocortical origin
Epilepsia (Copenhagen), v 59(3), pp 636-649
01 Mar 2018
PMID: 29442363
Featured in Collection : UN Sustainable Development Goals @ Drexel
Abstract
ObjectiveTo gain understanding of the neuronal mechanisms underlying regional seizure spread, the impact of regional synchrony between seizure focus and downstream networks on neuronal activity during the transition to seizure in those downstream networks was assessed.
MethodsSeven patients undergoing diagnostic intracranial electroencephalographic studies for surgical resection of epileptogenic regions were implanted with subdural clinical electrodes into the cortex (site of seizure initiation) and mesial temporal lobe (MTL) structures (downstream) as well as microwires into MTL. Neural activity was recorded (24/7) in parallel with the clinical intracranial electroencephalogram recordings for the duration of the patient's diagnostic stay. Changes in (1) regional synchrony (ie, coherence) between the presumptive neocortical seizure focus and MTL, (2) local synchrony between MTL neurons and their local field potential, and (3) neuronal firing rates within MTL in the time leading up to seizure were examined to study the mechanisms underlying seizure spread.
ResultsIn seizures of neocortical origin, an increase in regional synchrony preceded the spread of seizures into MTL (predominantly hippocampal). Within frequencies similar to those of regional synchrony, MTL networks showed an increase in unit-field coherence and a decrease in neuronal firing rate, specifically for inhibitory interneuron populations but not pyramidal cell populations.
SignificanceThese results suggest a mechanism of spreading seizures whereby the seizure focus first synchronizes local field potentials in downstream networks to the seizure activity. This change in local field coherence modifies the activity of interneuron populations in these downstream networks, which leads to the attenuation of interneuronal firing rate, effectively shutting down local interneuron populations prior to the spread of seizure. Therefore, regional synchrony may influence the failure of downstream interneurons to prevent the spread of the seizures during generalization.
Metrics
Details
- Title
- Increased neuronal synchrony prepares mesial temporal networks for seizures of neocortical origin
- Creators
- Amrit Misra - Drexel UniversityXianda Long - Drexel UniversityMichael R. Sperling - Thomas Jefferson UniversityAshwini D. Sharan - Thomas Jefferson UniversityKaren A. Moxon - University of California, Davis
- Publication Details
- Epilepsia (Copenhagen), v 59(3), pp 636-649
- Publisher
- Wiley
- Number of pages
- 14
- Grant note
- University of Pennsylvania Coulter Foundation MH55687; MH61975 / National Institutes of Health; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- School of Biomedical Engineering, Science, and Health Systems
- Web of Science ID
- WOS:000427008500015
- Scopus ID
- 2-s2.0-85041996402
- Other Identifier
- 991019169814604721
UN Sustainable Development Goals (SDGs)
This publication has contributed to the advancement of the following goals:
InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool:
- Collaboration types
- Domestic collaboration
- Web of Science research areas
- Clinical Neurology