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The Dynamics of Functional Brain Networks: Integrated Network States during Cognitive Task Performance.

ABSTRACT: Higher brain function relies upon the ability to flexibly integrate information across specialized communities of brain regions; however, it is unclear how this mechanism manifests over time. In this study, we used time-resolved network analysis of fMRI data to demonstrate that the human brain traverses between functional states that maximize either segregation into tight-knit communities or integration across otherwise disparate neural regions. Integrated states enable faster and more accurate performance on a cognitive task, and are associated with dilations in pupil diameter, suggesting that ascending neuromodulatory systems may govern the transition between these alternative modes of brain function. Together, our results confirm a direct link between cognitive performance and the dynamic reorganization of the network structure of the brain.

SUBMITTER: Shine JM

PROVIDER: S-EPMC5073034 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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The Dynamics of Functional Brain Networks: Integrated Network States during Cognitive Task Performance.

Shine James M JM Bissett Patrick G PG Bell Peter T PT Koyejo Oluwasanmi O Balsters Joshua H JH Gorgolewski Krzysztof J KJ Moodie Craig A CA Poldrack Russell A RA

Neuron 20160929 2

Higher brain function relies upon the ability to flexibly integrate information across specialized communities of brain regions; however, it is unclear how this mechanism manifests over time. In this study, we used time-resolved network analysis of fMRI data to demonstrate that the human brain traverses between functional states that maximize either segregation into tight-knit communities or integration across otherwise disparate neural regions. Integrated states enable faster and more accurate ...[more]

PMID: 27693256

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