title: Resting-State Magnetoencephalography Reveals Different Patterns of Aberrant Functional Connectivity in Combat-Related Mild Traumatic Brain Injury.
abstract: Blast mild traumatic brain injury (mTBI) is a leading cause of sustained impairment in military service members and veterans. However, the mechanism of persistent disability is not fully understood. The present study investigated disturbances in brain functioning in mTBI participants using a source-imaging-based approach to analyze functional connectivity (FC) from resting-state magnetoencephalography (rs-MEG). Study participants included 26 active-duty service members or veterans who had blast mTBI with persistent post-concussive symptoms, and 22 healthy control active-duty service members or veterans. The source time courses from regions of interest (ROIs) were used to compute ROI to whole-brain (ROI-global) FC for different frequency bands using two different measures: 1) time-lagged cross-correlation and 2) phase-lock synchrony. Compared with the controls, blast mTBI participants showed increased ROI-global FC in beta, gamma, and low-frequency bands, but not in the alpha band. Sources of abnormally increased FC included the: 1) prefrontal cortex (right ventromedial prefrontal cortex [vmPFC], right rostral anterior cingulate cortex [rACC]), and left ventrolateral and dorsolateral prefrontal cortex; 2) medial temporal lobe (bilateral parahippocampus, hippocampus, and amygdala); and 3) right putamen and cerebellum. In contrast, the blast mTBI group also showed decreased FC of the right frontal pole. Group differences were highly consistent across the two different FC measures. FC of the left ventrolateral prefrontal cortex correlated with executive functioning and processing speed in mTBI participants. Altogether, our findings of increased and decreased regionalpatterns of FC suggest that disturbances in intrinsic brain connectivity may be the result of multiple mechanisms, and are associated with cognitive sequelae of the injury.
authors.affiliation: 1 Radiology, Research, and Psychiatry Services, VA San Diego Healthcare System , San Diego, California.|2 Department of Radiology, University of California , San Diego, California.
authors.forename: Ming-Xiong
authors.initials: MX
authors.lastname: Huang
authors.affiliation: 1 Radiology, Research, and Psychiatry Services, VA San Diego Healthcare System , San Diego, California.|2 Department of Radiology, University of California , San Diego, California.
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Harrington
authors.affiliation: 1 Radiology, Research, and Psychiatry Services, VA San Diego Healthcare System , San Diego, California.|2 Department of Radiology, University of California , San Diego, California.
authors.forename: Ashley
authors.initials: A
authors.lastname: Robb Swan
authors.affiliation: 1 Radiology, Research, and Psychiatry Services, VA San Diego Healthcare System , San Diego, California.|2 Department of Radiology, University of California , San Diego, California.
authors.forename: Annemarie
authors.initials: A
authors.lastname: Angeles Quinto
authors.affiliation: 3 Department of Neuroscience, University of California , San Diego, California.
authors.forename: Sharon
authors.initials: S
authors.lastname: Nichols
authors.affiliation: 4 Naval Medical Center , San Diego, California.
authors.forename: Angela
authors.initials: A
authors.lastname: Drake
authors.affiliation: 2 Department of Radiology, University of California , San Diego, California.
authors.forename: Tao
authors.initials: T
authors.lastname: Song
authors.affiliation: 2 Department of Radiology, University of California , San Diego, California.
authors.forename: Mithun
authors.initials: M
authors.lastname: Diwakar
authors.affiliation: 5 Department of Bioengineering, University of California , San Diego, California.
authors.forename: Charles W
authors.initials: CW
authors.lastname: Huang
authors.affiliation: 6 Department of Psychiatry, University of California , San Diego, California.|7 VA Center of Excellence for Stress and Mental Health , San Diego, California.
authors.forename: Victoria B
authors.initials: VB
authors.lastname: Risbrough
authors.affiliation: 2 Department of Radiology, University of California , San Diego, California.
authors.forename: Anders
authors.initials: A
authors.lastname: Dale
authors.affiliation: 2 Department of Radiology, University of California , San Diego, California.
authors.forename: Hauke
authors.initials: H
authors.lastname: Bartsch
authors.affiliation: 1 Radiology, Research, and Psychiatry Services, VA San Diego Healthcare System , San Diego, California.|6 Department of Psychiatry, University of California , San Diego, California.|8 Aspire Center , VASDHS Residential Rehabilitation Treatment Program, San Diego, California.
authors.forename: Scott
authors.initials: S
authors.lastname: Matthews
authors.affiliation: 9 Westview High School , San Diego, California.
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Huang
authors.affiliation: 1 Radiology, Research, and Psychiatry Services, VA San Diego Healthcare System , San Diego, California.|2 Department of Radiology, University of California , San Diego, California.
authors.forename: Roland R
authors.initials: RR
authors.lastname: Lee
authors.affiliation: 1 Radiology, Research, and Psychiatry Services, VA San Diego Healthcare System , San Diego, California.|6 Department of Psychiatry, University of California , San Diego, California.|7 VA Center of Excellence for Stress and Mental Health , San Diego, California.
authors.forename: Dewleen G
authors.initials: DG
authors.lastname: Baker
mesh_terms: D000328:Adult; D000679:Amygdala / Q000503:physiopathology; D001753:Blast Injuries / Q000150:complications; D001924:Brain Concussion / Q000209:etiology / Q000503:physiopathology*; D058256:Brain Waves / Q000502:physiology*; D002531:Cerebellum / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000503:physiopathology*; D063132:Connectome / Q000379:methods*; D056344:Executive Function / Q000502:physiology; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods*; D008297:Male; D008889:Military Personnel; D020534:Parahippocampal Gyrus / Q000503:physiopathology; D038223:Post-Concussion Syndrome / Q000209:etiology / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000503:physiopathology; D011597:Psychomotor Performance / Q000502:physiology; D011699:Putamen / Q000503:physiopathology*; D014481:United States; D014728:Veterans; D055815:Young Adult
keywords: FC; MEG; TBI; blast brain injury; excitation; inhibition