Disrupted global metastability and static and dynamic brain connectivity across individuals in the Alzheimer’s disease continuum

• Published in: Scientific reports Vol. 7; no. 1; p. 40268
• Main Authors: Córdova-Palomera, Aldo, Kaufmann, Tobias, Persson, Karin, Alnæs, Dag, Doan, Nhat Trung, Moberget, Torgeir, Lund, Martina Jonette, Barca, Maria Lage, Engvig, Andreas, Brækhus, Anne, Engedal, Knut, Andreassen, Ole A., Selbæk, Geir, Westlye, Lars T.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11.01.2017; Nature Publishing Group
• Subjects: 59/57; 631/378/116/1925; 692/308/575; Aged; Alzheimer Disease - physiopathology; Alzheimer's disease; Brain; Brain - physiopathology; Brain Mapping; Cognitive ability; Cognitive Dysfunction - physiopathology; Computational neuroscience; Cross-Sectional Studies; Female; Functional magnetic resonance imaging; Humanities and Social Sciences; Humans; Magnetic Resonance Imaging; Male; Middle Aged; multidisciplinary; Nervous system; Neural networks; Neural Pathways - physiopathology; Neurodegenerative diseases; Nodes; Putamen; Science; Spatial analysis
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep40268

As findings on the neuropathological and behavioral components of Alzheimer’s disease (AD) continue to accrue, converging evidence suggests that macroscale brain functional disruptions may mediate their association. Recent developments on theoretical neuroscience indicate that instantaneous patterns of brain connectivity and metastability may be a key mechanism in neural communication underlying cognitive performance. However, the potential significance of these patterns across the AD spectrum remains virtually unexplored. We assessed the clinical sensitivity of static and dynamic functional brain disruptions across the AD spectrum using resting-state fMRI in a sample consisting of AD patients (n = 80) and subjects with either mild (n = 44) or subjective (n = 26) cognitive impairment (MCI, SCI). Spatial maps constituting the nodes in the functional brain network and their associated time-series were estimated using spatial group independent component analysis and dual regression, and whole-brain oscillatory activity was analyzed both globally (metastability) and locally (static and dynamic connectivity). Instantaneous phase metrics showed functional coupling alterations in AD compared to MCI and SCI, both static (putamen, dorsal and default-mode) and dynamic (temporal, frontal-superior and default-mode), along with decreased global metastability. The results suggest that brains of AD patients display altered oscillatory patterns, in agreement with theoretical premises on cognitive dynamics.