title: On the Stability of BOLD fMRI Correlations.
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.
authors: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Timothy O
authors: TO
authors: Laumann
authors: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Abraham Z
authors: AZ
authors: Snyder
authors: Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Anish
authors: A
authors: Mitra
authors: VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX 76711, USA.|Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX 75235, USA.
authors: Evan M
authors: EM
authors: Gordon
authors: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Caterina
authors: C
authors: Gratton
authors: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Babatunde
authors: B
authors: Adeyemo
authors: Department of Psychological and Brain Sciences, Washington University in St. Louis, St. Louis, MO 63110, USA.
authors: Adrian W
authors: AW
authors: Gilmore
authors: VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX 76711, USA.|Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX 75235, USA.
authors: Steven M
authors: SM
authors: Nelson
authors: Department of Psychological and Brain Sciences, Washington University in St. Louis, St. Louis, MO 63110, USA.
authors: Jeff J
authors: JJ
authors: Berg
authors: Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Deanna J
authors: DJ
authors: Greene
authors: Department of Mathematics, Washington University in St. Louis, St. Louis, MO 63130, USA.
authors: John E
authors: JE
authors: McCarthy
authors: Departmen of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Enzo
authors: E
authors: Tagliazucchi
authors: Institute for Medical Psychology, Christian-Albrechts-Universitat zu Kiel, Kiel, Germany.|Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Helmut
authors: H
authors: Laufs
authors: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Neurology, Brain Imaging Center, Goethe-Universitat Frankfurt am Main, Frankfurt, Germany.|Department of Neurology, Christian-Albrechts-Universitat zu Kiel, Kiel, Germany.
authors: Bradley L
authors: BL
authors: Schlaggar
authors: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Nico U F
authors: NUF
authors: Dosenbach
authors: Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.|Department of Psychological and Brain Sciences, Washington University in St. Louis, St. Louis, MO 63110, USA.|Department of Neurology, Christian-Albrechts-Universitat zu Kiel, Kiel, Germany.
authors: Steven E
authors: SE
authors: Petersen
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology; D001931:Brain Mapping / Q000379:methods; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009434:Neural Pathways / Q000502:physiology*; D010100:Oxygen / Q000378:metabolism; D012146:Rest / Q000502:physiology*; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: BOLD fMRI; dynamics; functional connectivity; nonstationarity; resting state