title: Static and Dynamic Intrinsic Connectivity following Mild Traumatic Brain Injury.
abstract: Mild traumatic brain injury (mTBI) is the most common neurological disorder and is typically characterized by temporally limited cognitive impairment and emotional symptoms. Previous examinations of intrinsic resting state networks in mTBI have primarily focused on abnormalities in static functional connectivity, and deficits in dynamic functional connectivity have yet to be explored in this population. Resting-state data was collected on 48 semi-acute (mean = 14 days post-injury) mTBI patients and 48 matched healthy controls. A high-dimensional independent component analysis (N = 100) was utilized to parcellate intrinsic connectivity networks (ICN), with a priori hypotheses focusing on the default-mode network (DMN) and sub-cortical structures. Dynamic connectivity was characterized using a sliding window approach over 126 temporal epochs, with standard deviation serving as the primary outcome measure. Finally, distribution-corrected z-scores (DisCo-Z) were calculated to investigate changes in connectivity in a spatially invariant manner on a per-subject basis. Following appropriate correction for multiple comparisons, no significant group differences were evident on measures of static or dynamic connectivity within a priori ICN. Reduced (HC > mTBI patients) static connectivity was observed in the DMN at uncorrected (p < 0.005) thresholds. Finally, a trend (p = 0.07) for decreased dynamic connectivity in patients across all ICN was observed during spatially invariant analyses (DisCo-Z). In the semi-acute phase of recovery, mTBI was not reliably associated with abnormalities in static or dynamic functional connectivity within the DMN or sub-cortical structures.
authors.affiliation: 1 The Mind Research Network/Lovelace Biomedical and Environmental Research Institute , Albuquerque, New Mexico.|2 Department of Neurology, University of New Mexico School of Medicine , Albuquerque, New Mexico.|3 Department of Psychology, University of New Mexico , Albuquerque, New Mexico.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Mayer
authors.affiliation: 1 The Mind Research Network/Lovelace Biomedical and Environmental Research Institute , Albuquerque, New Mexico.
authors.forename: Josef M
authors.initials: JM
authors.lastname: Ling
authors.affiliation: 1 The Mind Research Network/Lovelace Biomedical and Environmental Research Institute , Albuquerque, New Mexico.
authors.forename: Elena A
authors.initials: EA
authors.lastname: Allen
authors.affiliation: 1 The Mind Research Network/Lovelace Biomedical and Environmental Research Institute , Albuquerque, New Mexico.
authors.forename: Stefan D
authors.initials: SD
authors.lastname: Klimaj
authors.affiliation: 3 Department of Psychology, University of New Mexico , Albuquerque, New Mexico.
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Yeo
authors.affiliation: 1 The Mind Research Network/Lovelace Biomedical and Environmental Research Institute , Albuquerque, New Mexico.
authors.forename: Faith M
authors.initials: FM
authors.lastname: Hanlon
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000503:physiopathology*; D001924:Brain Concussion / Q000503:physiopathology*; D001930:Brain Injuries / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009415:Nerve Net / Q000503:physiopathology*; D055815:Young Adult
keywords: ICA; RSFC; functional; mild TBI; resting state networks