Node Accessibility in Cortical Networks During Motor Tasks
Recent findings suggest that the preparation and execution of voluntary self-paced movements are accompanied by the coordination of the oscillatory activities of distributed brain regions. Here, we use electroencephalographic source imaging methods to estimate the cortical movement-related oscillatory activity during finger extension movements. Then, we apply network theory to investigate changes (expressed as differences from the baseline) in the connectivity structure of cortical networks related to the preparation and execution of the movement. We compute the topological accessibility of different cortical areas, measuring how well an area can be reached by the rest of the network. Analysis of cortical networks reveals specific agglomerates of cortical sources that become less accessible during the preparation and the execution of the finger movements. The observed changes neither could be explained by other measures based on geodesics or on multiple paths, nor by power changes in the cortical oscillations.
KeywordsComplex networks Brain connectivity Voluntary self-paced movements
This study was supported in part by Cochlear Inc. and by a grant of “Ministero dell’Istruzione, dell’Universita e della Ricerca”, Direzione Generale per l’ Internazionalizzazione della Ricerca, in a bilateral project between Italy and Hungary. M. V. acknowledges financial support from the Spanish Ministry of Science and Innovation; Juan de la Cierva Programme Ref. JCI-2010-07876. F. D. V. F. is founded by the French program “Investissements d’avenir” ANR-10-IAIHU-06. M.V. and M.C. acknowledge financial support from the Gobierno de Navarra, Education Department, Jerónimo de Ayanz Programme M. C. thanks to the CIMA and University of Navarra, for their kind hospitality during the different visits for the preparation of this work.
Conflict of Interest
The authors declare that they have no conflict of interest.
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