Brain activity at rest: A multiscale hierarchical functional organization
Journal of Neurophysiology. 2011-06-01; 105(6): 2753-2763
Lire sur PubMed
1. J Neurophysiol. 2011 Jun;105(6):2753-63. doi: 10.1152/jn.00895.2010. Epub 2011
Brain activity at rest: a multiscale hierarchical functional organization.
Doucet G(1), Naveau M, Petit L, Delcroix N, Zago L, Crivello F, Jobard G,
Tzourio-Mazoyer N, Mazoyer B, Mellet E, Joliot M.
(1)Univ. de Bordeaux, Bordeaux, France.
Spontaneous brain activity was mapped with functional MRI (fMRI) in a sample of
180 subjects while in a conscious resting-state condition. With the use of
independent component analysis (ICA) of each individual fMRI signal and
classification of the ICA-defined components across subjects, a set of 23
resting-state networks (RNs) was identified. Functional connectivity between each
pair of RNs was assessed using temporal correlation analyses in the 0.01- to
0.1-Hz frequency band, and the corresponding set of correlation coefficients was
used to obtain a hierarchical clustering of the 23 RNs. At the highest
hierarchical level, we found two anticorrelated systems in charge of intrinsic
and extrinsic processing, respectively. At a lower level, the intrinsic system
appears to be partitioned in three modules that subserve generation of
spontaneous thoughts (M1a; default mode), inner maintenance and manipulation of
information (M1b), and cognitive control and switching activity (M1c),
respectively. The extrinsic system was found to be made of two distinct modules:
one including primary somatosensory and auditory areas and the dorsal attentional
network (M2a) and the other encompassing the visual areas (M2b). Functional
connectivity analyses revealed that M1b played a central role in the functioning
of the intrinsic system, whereas M1c seems to mediate exchange of information
between the intrinsic and extrinsic systems.
PMID: 21430278 [Indexed for MEDLINE]