Anticorrelations in resting state networks without global signal regression

Xiaoqian Chai, Alfonso Nieto Castañán, Dost Öngür, Susan Whitfield-Gabrieli

Research output: Contribution to journalArticle

Abstract

Anticorrelated relationships in spontaneous signal fluctuation have been previously observed in resting-state functional magnetic resonance imaging (fMRI). In particular, it was proposed that there exists two systems in the brain that are intrinsically organized into anticorrelated networks, the default mode network, which usually exhibits task-related deactivations, and the task-positive network, which usually exhibits task-related activations during tasks that demands external attention. However, it is currently under debate whether the anticorrelations observed in resting state fMRI were valid or were instead artificially introduced by global signal regression, a common preprocessing technique to remove physiological and other noise in resting-state fMRI signal. We examined positive and negative correlations in resting-state connectivity using two different preprocessing methods: a component base noise reduction method (CompCor, Behzadi et al., 2007), in which principal components from noise regions-of-interest were removed, and the global signal regression method. Robust anticorrelations between a default mode network seed region in the medial prefrontal cortex and regions of the task-positive network were observed under both methods. Specificity of the anticorrelations was similar between the two methods. Specificity and sensitivity for positive correlations were higher under CompCor compared to the global regression method. Our results suggest that anticorrelations observed in resting-state connectivity are not an artifact introduced by global signal regression and might have biological origins, and that the CompCor method can be used to examine valid anticorrelations during rest.

Original languageEnglish (US)
Pages (from-to)1420-1428
Number of pages9
JournalNeuroImage
Volume59
Issue number2
DOIs
Publication statusPublished - Jan 16 2012
Externally publishedYes

    Fingerprint

Keywords

  • Default mode network
  • FMRI
  • Functional connectivity
  • Negative correlations
  • Physiological noise
  • Task-positive network

ASJC Scopus subject areas

  • Cognitive Neuroscience
  • Neurology

Cite this

Chai, X., Castañán, A. N., Öngür, D., & Whitfield-Gabrieli, S. (2012). Anticorrelations in resting state networks without global signal regression. NeuroImage, 59(2), 1420-1428. https://doi.org/10.1016/j.neuroimage.2011.08.048