Accéder directement au contenu Accéder directement à la navigation
Article dans une revue

Pattern changes of EEG oscillations and BOLD signals associated with temporal lobe epilepsy as revealed by a working memory task

Abstract : BACKGROUND: It is known that the abnormal neural activity in epilepsy may be associated to the reorganization of neural circuits and brain plasticity in various ways. On that basis, we hypothesized that changes in neuronal circuitry due to epilepsy could lead to measurable variations in patterns of both EEG and BOLD signals in patients performing some cognitive task as compared to what would be obtained in normal condition. Thus, the aim of this study was to compare the cerebral areas involved in EEG oscillations versus fMRI signal patterns during a working memory (WM) task in normal controls and patients with refractory mesial temporal lobe epilepsy (MTLE) associated with hippocampal sclerosis (HS). The study included six patients with left MTLE-HS (left-HS group) and seven normal controls (control group) matched to the patients by age and educational level, both groups undergoing a blocked design paradigm based on Sternberg test during separated EEG and fMRI sessions. This test consisted of encoding and maintenance of a variable number of consonant letters on WM. RESULTS: EEG analysis for the encoding period revealed the presence of theta and alpha oscillations in the frontal and parietal areas, respectively. Likewise, fMRI showed the co-occurrence of positive and negative BOLD signals in both brain regions. As for the maintenance period, whereas EEG analysis revealed disappearance of theta oscillation, fMRI showed decrease of positive BOLD in frontal area and increase of negative BOLD in the posterior part of the brain. CONCLUSIONS: Generally speaking, these patterns of electrophysiological and hemodynamic signals were observed for both control and left-HS groups. However, the data also revealed remarkable differences between these groups that are consistent with the hypothesis of reorganization of brain circuitry associated with epilepsy.
Type de document :
Article dans une revue
Liste complète des métadonnées

Littérature citée [64 références]  Voir  Masquer  Télécharger

https://hal.umontpellier.fr/hal-01952404
Contributeur : Anthony Herrada <>
Soumis le : mercredi 12 décembre 2018 - 10:50:55
Dernière modification le : vendredi 12 juin 2020 - 16:58:21
Archivage à long terme le : : mercredi 13 mars 2019 - 13:37:03

Fichier

document.pdf
Fichiers éditeurs autorisés sur une archive ouverte

Identifiants

Collections

Citation

Helka Ozelo, Andréa Alessio, Maurício Sercheli, Elizabeth Bilevicius, Tatiane Pedro, et al.. Pattern changes of EEG oscillations and BOLD signals associated with temporal lobe epilepsy as revealed by a working memory task. BMC Neuroscience, BioMed Central, 2014, -, 15, pp.52. ⟨10.1186/1471-2202-15-52⟩. ⟨hal-01952404⟩

Partager

Métriques

Consultations de la notice

68

Téléchargements de fichiers

108