Mechanisms of evoked and induced responses in MEG/EEG.

Abstract : Cortical responses, recorded by electroencephalography and magnetoencephalography, can be characterized in the time domain, to study event-related potentials/fields, or in the time-frequency domain, to study oscillatory activity. In the literature, there is a common conception that evoked, induced, and on-going oscillations reflect different neuronal processes and mechanisms. In this work, we consider the relationship between the mechanisms generating neuronal transients and how they are expressed in terms of evoked and induced power. This relationship is addressed using a neuronally realistic model of interacting neuronal subpopulations. Neuronal transients were generated by changing neuronal input (a dynamic mechanism) or by perturbing the systems coupling parameters (a structural mechanism) to produce induced responses. By applying conventional time-frequency analyses, we show that, in contradistinction to common conceptions, induced and evoked oscillations are perhaps more related than previously reported. Specifically, structural mechanisms normally associated with induced responses can be expressed in evoked power. Conversely, dynamic mechanisms posited for evoked responses can induce responses, if there is variation in neuronal input. We conclude, it may be better to consider evoked responses as the results of mixed dynamic and structural effects. We introduce adjusted power to complement induced power. Adjusted power is unaffected by trial-to-trial variations in input and can be attributed to structural perturbations without ambiguity.
Type de document :
Article dans une revue
NeuroImage, Elsevier, 2006, 31 (4), pp.1580-91. 〈10.1016/j.neuroimage.2006.02.034〉
Liste complète des métadonnées

Littérature citée [33 références]  Voir  Masquer  Télécharger

http://www.hal.inserm.fr/inserm-00388968
Contributeur : Olivier David <>
Soumis le : jeudi 23 juillet 2009 - 18:17:40
Dernière modification le : jeudi 11 janvier 2018 - 02:37:01
Document(s) archivé(s) le : samedi 26 novembre 2016 - 09:22:49

Identifiants

Collections

Citation

Olivier David, James Kilner, Karl Friston. Mechanisms of evoked and induced responses in MEG/EEG.. NeuroImage, Elsevier, 2006, 31 (4), pp.1580-91. 〈10.1016/j.neuroimage.2006.02.034〉. 〈inserm-00388968〉

Partager

Métriques

Consultations de la notice

192

Téléchargements de fichiers

512