Hubs of Anticorrelation in High-Resolution Resting-State Functional Connectivity Network Architecture.
A major focus of brain research recently has been to map the resting-state functional connectivity (rsFC) network architecture of the normal brain and pathology through functional magnetic resonance imaging. However, the phenomenon of anticorrelations in resting-state signals between different brain regions has not been adequately examined. The preponderance of studies on resting-state fMRI (rsFMRI) have either ignored anticorrelations in rsFC networks or adopted methods in data analysis, which have rendered anticorrelations in rsFC networks uninterpretable. The few studies that have examined anticorrelations in rsFC networks using conventional methods have found anticorrelations to be weak in strength and not very reproducible across subjects. Anticorrelations in rsFC network architecture could reflect mechanisms that subserve a number of important brain processes. In this preliminary study, we examined the properties of anticorrelated rsFC networks by systematically focusing on negative cross-correlation coefficients (CCs) among rsFMRI voxel time series across the brain with graph theory-based network analysis. A number of methods were implemented to enhance the neuronal specificity of resting-state functional connections that yield negative CCs, although at the cost of decreased sensitivity. Hubs of anticorrelation were seen in a number of cortical and subcortical brain regions. Examination of the anticorrelation maps of these hubs indicated that negative CCs in rsFC network architecture highlight a number of regulatory interactions between brain networks and regions, including reciprocal modulations, suppression, inhibition, and neurofeedback.
1 Department of Radiology and Imaging Sciences, Emory University School of Medicine , Atlanta, Georgia .
Kaundinya
K
Gopinath
1 Department of Radiology and Imaging Sciences, Emory University School of Medicine , Atlanta, Georgia .
Venkatagiri
V
Krishnamurthy
2 Center for Systems Imaging, Emory University School of Medicine , Atlanta, Georgia .
Romeo
R
Cabanban
3 VA RR&D Center of Excellence (151R), Atlanta VA Medical Center , Decatur, Georgia .|4 Department of Neurology, Emory University School of Medicine , Atlanta, Georgia .|5 Department of Psychology, Georgia State University , Atlanta, Georgia .
Bruce A
BA
Crosson
D000328:Adult; D001921:Brain / Q000098:blood supply / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000098:blood supply / Q000502:physiology*; D009434:Neural Pathways / Q000098:blood supply / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D012146:Rest; D013223:Statistics as Topic
D010100:Oxygen
anticorrelated networks; hubs of anticorrelation; resting state fMRI; resting state functional connectivity; rsFC networks