Title
Age-related changes in modular organization of human brain functional networks.
Abstract
Graph theory allows us to quantify any complex system, e.g., in social sciences, biology or technology, that can be abstractly described as a set of nodes and links. Here we derived human brain functional networks from fMRI measurements of endogenous, low frequency, correlated oscillations in 90 cortical and subcortical regions for two groups of healthy (young and older) participants. We investigated the modular structure of these networks and tested the hypothesis that normal brain aging might be associated with changes in modularity of sparse networks. Newman's modularity metric was maximised and topological roles were assigned to brain regions depending on their specific contributions to intra- and inter-modular connectivity. Both young and older brain networks demonstrated significantly non-random modularity. The young brain network was decomposed into 3 major modules: central and posterior modules, which comprised mainly nodes with few inter-modular connections, and a dorsal fronto-cingulo-parietal module, which comprised mainly nodes with extensive inter-modular connections. The mean network in the older group also included posterior, superior central and dorsal fronto-striato-thalamic modules but the number of intermodular connections to frontal modular regions was significantly reduced, whereas the number of connector nodes in posterior and central modules was increased.
Year
DOI
Venue
2009
10.1016/j.neuroimage.2008.09.062
NeuroImage
Keywords
Field
DocType
Aging,Complex networks,Functional MRI,Modularity
Graph theory,Neuroscience,Biology,Nerve net,Human brain,Complex network,Modular design,Neuroplasticity,Modularity
Journal
Volume
Issue
ISSN
44
3
1053-8119
Citations 
PageRank 
References 
112
7.34
4
Authors
4
Search Limit
100112
Name
Order
Citations
PageRank
David Meunier115112.43
Sophie Achard231528.86
Alexa Morcom316316.47
Ed Bullmore41331150.94