title: White matter damage disorganizes brain functional networks in amnestic mild cognitive impairment.
abstract: Although progressive functional brain network disruption has been one of the hallmarks of Alzheimer's Disease, little is known about the origin of this functional impairment that underlies cognitive symptoms. We investigated how the loss of white matter (WM) integrity disrupts the organization of the functional networks at different frequency bands. The analyses were performed in a sample of healthy elders and mild cognitive impairment (MCI) subjects. Spontaneous brain magnetic activity (measured with magnetoencephalography) was characterized with phase synchronization analysis, and graph theory was applied to the functional networks. We identified WM areas (using diffusion weighted magnetic resonance imaging) that showed a statistical dependence between the fractional anisotropy and the graph metrics. These regions are part of an episodic memory network and were also related to cognitive functions. Our data support the hypothesis that disruption of the anatomical networks influences the organization at the functional level resulting in the prodromal dementia syndrome of MCI.
authors.affiliation: 1 Laboratory of Cognitive and Computational Neuroscience, Center of Biomedical Technology, Universidad Politécnica de Madrid (UPM) , Madrid, Spain .
authors.forename: José Angel
authors.initials: JA
authors.lastname: Pineda-Pardo
authors.forename: Pilar
authors.initials: P
authors.lastname: Garcés
authors.forename: María Eugenia
authors.initials: ME
authors.lastname: López
authors.forename: Sara
authors.initials: S
authors.lastname: Aurtenetxe
authors.forename: Pablo
authors.initials: P
authors.lastname: Cuesta
authors.forename: Alberto
authors.initials: A
authors.lastname: Marcos
authors.forename: Pedro
authors.initials: P
authors.lastname: Montejo
authors.forename: Miguel
authors.initials: M
authors.lastname: Yus
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Hernández-Tamames
authors.forename: Francisco
authors.initials: F
authors.lastname: del Pozo
authors.forename: James T
authors.initials: JT
authors.lastname: Becker
authors.forename: Fernando
authors.initials: F
authors.lastname: Maestú
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000647:Amnesia / Q000503:physiopathology*; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D060825:Cognitive Dysfunction / Q000503:physiopathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods; D008297:Male; D009415:Nerve Net / Q000503:physiopathology*; D066127:White Matter / Q000473:pathology
keywords: diffusion tensor image; graph theory; magnetoencephalography; mild cognitive impairment; multimodal integration; phase synchronization