On the Stability of BOLD fMRI Correlations

Timothy O. Laumann, Abraham Z. Snyder, Anish Mitra, Evan M. Gordon, Caterina Gratton, Babatunde Adeyemo, Adrian W. Gilmore, Steven M. Nelson, Jeff J. Berg, Deanna J. Greene, John E. McCarthy, Enzo Tagliazucchi, Helmut Laufs, Bradley L. Schlaggar, Nico U. F. Dosenbach, Steven E. Petersen: Cerebral Cortex, Volume 27, Issue 10, 1 October 2017, Pages 4719-4732 Read More

Abstract

Measurement of correlations between brain regions (functional connectivity) using blood oxygen level dependent (BOLD) fMRI has proven to be a powerful tool for studying the functional organization of the brain. Recently, dynamic functional connectivity has emerged as a major topic in the resting-state BOLD fMRI literature. Here, using simulations and multiple sets of empirical observations, we confirm that imposed task states can alter the correlation structure of BOLD activity. However, we find that observations of “dynamic” BOLD correlations during the resting state are largely explained by sampling variability. Beyond sampling variability, the largest part of observed “dynamics” during rest is attributable to head motion. An additional component of dynamic variability during rest is attributable to fluctuating sleep state. Thus, aside from the preceding explanatory factors, a single correlation structure – as opposed to a sequence of distinct correlation structures – may adequately describe the resting state as measured by BOLD fMRI. These results suggest that resting-state BOLD correlations do not primarily reflect moment-to-moment changes in cognitive content. Rather, resting-state BOLD correlations may predominantly reflect processes concerned with the maintenance of the long-term stability of the brain’s functional organization. © The Author 2016. Published by Oxford University Press. All rights reserved.
Full Text

.

Posted on November 14, 2017
Posted in: HPAN, Neurodegeneration, Neurogenetics & Transcriptomics, Neurovascular Injury & Repair, Publications Authors: , ,