Transcranial Magnetic Stimulation Combined with EEG Reveals Covert States of Elevated Excitability in the Human Epileptic Brain.

Details

Serval ID
serval:BIB_C96180A6D4F3
Type
Article: article from journal or magazin.
Collection
Publications
Title
Transcranial Magnetic Stimulation Combined with EEG Reveals Covert States of Elevated Excitability in the Human Epileptic Brain.
Journal
International Journal of Neural Systems
Author(s)
Kimiskidis V.K., Koutlis C., Tsimpiris A., Kälviäinen R., Ryvlin P., Kugiumtzis D.
ISSN
0129-0657 (Print)
ISSN-L
0129-0657
Publication state
Published
Issued date
2015
Peer-reviewed
Oui
Volume
25
Number
5
Pages
1550018
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Abstract
BACKGROUND: Transcranial magnetic stimulation combined with electroencephalogram (TMS-EEG) can be used to explore the dynamical state of neuronal networks. In patients with epilepsy, TMS can induce epileptiform discharges (EDs) with a stochastic occurrence despite constant stimulation parameters. This observation raises the possibility that the pre-stimulation period contains multiple covert states of brain excitability some of which are associated with the generation of EDs.
OBJECTIVE: To investigate whether the interictal period contains "high excitability" states that upon brain stimulation produce EDs and can be differentiated from "low excitability" states producing normal appearing TMS-EEG responses.
METHODS: In a cohort of 25 patients with Genetic Generalized Epilepsies (GGE) we identified two subjects characterized by the intermittent development of TMS-induced EDs. The high-excitability in the pre-stimulation period was assessed using multiple measures of univariate time series analysis. Measures providing optimal discrimination were identified by feature selection techniques. The "high excitability" states emerged in multiple loci (indicating diffuse cortical hyperexcitability) and were clearly differentiated on the basis of 14 measures from "low excitability" states (accuracy = 0.7).
CONCLUSION: In GGE, the interictal period contains multiple, quasi-stable covert states of excitability a class of which is associated with the generation of TMS-induced EDs. The relevance of these findings to theoretical models of ictogenesis is discussed.
Keywords
Adolescent, Adult, Area Under Curve, Brain/physiopathology, Cohort Studies, Electroencephalography/methods, Epilepsy, Generalized/physiopathology, Female, Humans, Male, Middle Aged, ROC Curve, Transcranial Magnetic Stimulation/methods, Young Adult
Pubmed
Web of science
Create date
13/07/2015 10:27
Last modification date
20/08/2019 16:44
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