title: Disrupted topological organization of resting-state functional brain network in subcortical vascular mild cognitive impairment.
abstract: OBJECTIVE
  Neuroimaging studies have demonstrated both structural and functional abnormalities in widespread brain regions in patients with subcortical vascular mild cognitive impairment (svMCI). However, whether and how these changes alter functional brain network organization remains largely unknown.
  
  
  METHODS
  We recruited 21 patients with svMCI and 26 healthy control (HC) subjects who underwent resting-state functional magnetic resonance imaging scans. Graph theory-based network analyses were used to investigate alterations in the topological organization of functional brain networks.
  
  
  RESULTS
  Compared with the HC individuals, the patients with svMCI showed disrupted global network topology with significantly increased path length and modularity. Modular structure was also impaired in the svMCI patients with a notable rearrangement of the executive control module, where the parietal regions were split out and grouped as a separate module. The svMCI patients also revealed deficits in the intra- and/or intermodule connectivity of several brain regions. Specifically, the within-module degree was decreased in the middle cingulate gyrus while it was increased in the left anterior insula, medial prefrontal cortex and cuneus. Additionally, increased intermodule connectivity was observed in the inferior and superior parietal gyrus, which was associated with worse cognitive performance in the svMCI patients.
  
  
  CONCLUSIONS
  Together, our results indicate that svMCI patients exhibit dysregulation of the topological organization of functional brain networks, which has important implications for understanding the pathophysiological mechanism of svMCI.
authors.affiliation: Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: Li-Ye
authors.initials: LY
authors.lastname: Yi
authors.affiliation: Neuroimaging Research Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA.
authors.forename: Xia
authors.initials: X
authors.lastname: Liang
authors.affiliation: Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: Da-Ming
authors.initials: DM
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Sun
authors.affiliation: Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: Sun
authors.initials: S
authors.lastname: Ying
authors.affiliation: Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: Dong-Bo
authors.initials: DB
authors.lastname: Yang
authors.affiliation: Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: Qing-Bin
authors.initials: QB
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: Chuan-Lu
authors.initials: CL
authors.lastname: Jiang
authors.affiliation: Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.|Department of Neurology, XuanWu Hospital, Capital Medical University, Beijing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D060825:Cognitive Dysfunction / Q000503:physiopathology*; D015140:Dementia, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D012146:Rest
keywords: Connectomics; Executive-control network; Module; Small-worldness; Subcortical vascular mild cognitive impairment