Title
Competition between functional brain networks mediates behavioral variability
Abstract
Increased intraindividual variability (IIV) is a hallmark of disorders of attention. Recent work has linked these disorders to abnormalities in a “default mode” network, comprising brain regions routinely deactivated during goal-directed cognitive tasks. Findings from a study of the neural basis of attentional lapses suggest that a competitive relationship between the “task-negative” default mode network and regions of a “task-positive” attentional network is a potential locus of dysfunction in individuals with increased IIV. Resting state studies have shown that this competitive relationship is intrinsically represented in the brain, in the form of a negative correlation or antiphase relationship between spontaneous activity occurring in the two networks. We quantified the negative correlation between these two networks in 26 subjects, during active (Eriksen flanker task) and resting state scans. We hypothesized that the strength of the negative correlation is an index of the degree of regulation of activity in the default mode and task-positive networks and would be positively related to consistent behavioral performance. We found that the strength of the correlation between the two networks varies across individuals. These individual differences appear to be behaviorally relevant, as interindividual variation in the strength of the correlation was significantly related to individual differences in response time variability: the stronger the negative correlation (i.e., the closer to 180° antiphase), the less variable the behavioral performance. This relationship was moderately consistent across resting and task conditions, suggesting that the measure indexes moderately stable individual differences in the integrity of functional brain networks. We discuss the implications of these findings for our understanding of the behavioral significance of spontaneous brain activity, in both healthy and clinical populations.
Year
DOI
Venue
2008
10.1016/j.neuroimage.2007.08.008
NeuroImage
Keywords
Field
DocType
Resting state,Default mode,Intraindividual variability,Task-positive,Spontaneous fluctuations,fMRI
Developmental psychology,Default mode network,Task-positive network,Nerve net,Elementary cognitive task,Eriksen flanker task,Resting state fMRI,Psychology,Cognitive psychology,Brain activity and meditation,Correlation
Journal
Volume
Issue
ISSN
39
1
1053-8119
Citations 
PageRank 
References 
123
10.16
11
Authors
5
Search Limit
100123
Name
Order
Citations
PageRank
Clare Kelly161934.17
Lucina Q Uddin235226.92
Biswal Bharat B320420.86
F Xavier Castellanos483444.64
Michael P Milham588448.19