title: Correlation between structural and functional connectivity impairment in amyotrophic lateral sclerosis.
abstract: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease, characterized by progressive loss of motor function. While the pathogenesis of ALS remains largely unknown, imaging studies of the brain should lead to more insight into structural and functional disease effects on the brain network, which may provide valuable information on the underlying disease process. This study investigates the correlation between changes in structural connectivity (SC) and functional connectivity (FC) of the brain network in ALS. Structural reconstructions of the brain network, derived from diffusion weighted imaging (DWI), were obtained from 64 patients and 27 healthy controls. Functional interactions between brain regions were derived from resting-state fMRI. Our results show that (i) the most structurally affected connections considerably overlap with the most functionally impaired connections, (ii) direct connections of the motor cortex are both structurally and functionally more affected than connections at greater topological distance from the motor cortex, and (iii) there is a strong positive correlation between changes in SC and FC averaged per brain region (r = 0.44, P < 0.0001). Our findings indicate that structural and functional network degeneration in ALS is coupled, suggesting the pathogenic process affects both SC and FC of the brain, with the most prominent effects in SC.
authors.affiliation: Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, Netherlands.
authors.forename: Ruben
authors.initials: R
authors.lastname: Schmidt
authors.forename: Esther
authors.initials: E
authors.lastname: Verstraete
authors.forename: Marcel A
authors.initials: MA
authors.lastname: de Reus
authors.forename: Jan H
authors.initials: JH
authors.lastname: Veldink
authors.forename: Leonard H
authors.initials: LH
authors.lastname: van den Berg
authors.forename: Martijn P
authors.initials: MP
authors.lastname: van den Heuvel
mesh_terms: D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000473:pathology* / Q000503:physiopathology*; D001921:Brain / Q000473:pathology* / Q000503:physiopathology*; D001931:Brain Mapping; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology / Q000503:physiopathology; D009434:Neural Pathways / Q000473:pathology / Q000503:physiopathology; D055815:Young Adult
keywords: amyotrophic lateral sclerosis; connectivity; diffusion weighted imaging; magnetic resonance imaging; resting-state