title: Large-scale functional network overlap is a general property of brain functional organization: Reconciling inconsistent fMRI findings from general-linear-model-based analyses.
abstract: Functional magnetic resonance imaging (fMRI) studies regularly use univariate general-linear-model-based analyses (GLM). Their findings are often inconsistent across different studies, perhaps because of several fundamental brain properties including functional heterogeneity, balanced excitation and inhibition (E/I), and sparseness of neuronal activities. These properties stipulate heterogeneous neuronal activities in the same voxels and likely limit the sensitivity and specificity of GLM. This paper selectively reviews findings of histological and electrophysiological studies and fMRI spatial independent component analysis (sICA) and reports new findings by applying sICA to two existing datasets. The extant and new findings consistently demonstrate several novel features of brain functional organization not revealed by GLM. They include overlap of large-scale functional networks (FNs) and their concurrent opposite modulations, and no significant modulations in activity of most FNs across the whole brain during any task conditions. These novel features of brain functional organization are highly consistent with the brain's properties of functional heterogeneity, balanced E/I, and sparseness of neuronal activity, and may help reconcile inconsistent GLM findings.
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States. Electronic address: Jiansong.xu@yale.edu.
authors: Jiansong
authors: J
authors: Xu
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States; Child Study Center, Yale University School of Medicine, New Haven, CT 06510, United States; Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, United States; CASAColumbia, Yale University School of Medicine, New Haven, CT 06510, United States; The Connecticut Mental Health Center, New Haven, CT 06519, United States.
authors: Marc N
authors: MN
authors: Potenza
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States; The Mind Research Network & LBERI, Albuquerque, NM 87131, United States; Dept of ECE, The University of New Mexico, Albuquerque, NM, 87131, United States.
authors: Vince D
authors: VD
authors: Calhoun
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States.
authors: Rubin
authors: R
authors: Zhang
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States; CASAColumbia, Yale University School of Medicine, New Haven, CT 06510, United States.
authors: Sarah W
authors: SW
authors: Yip
authors: Department of Neurosciences, University of Toledo, Toledo, OH, 43614, United States.
authors: John T
authors: JT
authors: Wall
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States; Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, United States; Olin Neuropsychiatry Research Center, Institute of Living, Hartford, CT 06106, United States.
authors: Godfrey D
authors: GD
authors: Pearlson
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States.
authors: Patrick D
authors: PD
authors: Worhunsky
authors: Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, United States.
authors: Kathleen A
authors: KA
authors: Garrison
authors: The Center for Brain Sciences, Harvard University, Cambridge, MA, United States; U.S. Army Natick Soldier Research, Development and Engineering Center, United States.
authors: Joseph M
authors: JM
authors: Moran
mesh_terms: D001921:Brain; D001931:Brain Mapping; D006801:Humans; D008279:Magnetic Resonance Imaging
keywords: Balanced excitation and inhibition; Default mode network; Functional network overlap; GLM; ICA; Sparseness of neuronal activity; fMRI