Changes in functional network centrality underlie cognitive dysfunction and physical disability in multiple sclerosis

Abstract

In MS, areas in the ventral stream and sensorimotor cortex appear to become less central in the entire functional network of the brain, which is associated with clinico-cognitive dysfunction. The thalamus, however, displays increased connectivity with these areas. These findings may aid in further elucidating the function of functional reorganization processes in MS.

Effects of disease modifying therapies on brain and grey matter atrophy in relapsing remitting multiple sclerosis

“…Indeed, spinal cord atrophy was described in the early MS stages [69,70,74] but was much more pronounced in PPMS and SPMS [76,77], whereas spinal GM volume inversely correlated with physical disability (measured with EDSS, T25FW, and 9-Hole Peg Test scores) in patients with CIS suggestive of MS, and was more predictive for EDSS or Multiple Sclerosis Functional Composite (MSFC) scores that others MRI parameters [68][69][70][75][76][77][78]. Correlations between cognitive impairment and regional, cortical and total GM volume have also been demonstrated with significant agreement among studies [79][80][81][82][83][84][85][86][87]. Moreover, associations between specific cognitive domains and various quantitative GM measures (such as thalamic volume, cortical thickness and total GM volume) were found to be strong independent predictors of cognitive decline [23,26,34,84,87,88].…”

Gray matter damage in multiple sclerosis: Impact on clinical symptoms

“…Its relative success might also serve as an explanation of symptom variation. fMRI studies found increased functional connectivity in the early disease stages Bonavita et al, 2011;Faivre et al, 2012;Tona et al, 2014), and decreased connectivity in more advanced stages Bonavita et al, 2011;Gallo et al, 2012;Tona et al, 2014;Schoonheim et al, 2014). Nonetheless, in these studies the correlations of connectivity changes with cognitive performance are still often contradictory, and warrant further exploration (Schoonheim et al, 2015).…”

Global brain connectivity alterations in patients with schizophrenia and bipolar spectrum disorders

“…In line with previous studies, 38,39 we used clusters with significant diag nostic effects on ECM as seeds in dual regression (DR) 40,41 in order to investigate the regional contribution. Briefly, the first step in the DR analysis uses the clusters as seeds or spatial regressors to estimate the seed time course for each individual.…”

“…The EC map across participants showed a network of high-centrality regions similar to other ECM studies, supporting the reliability of the method. 35,39,52 However, relying on measures of full correlations when assessing the structure of the brain network, which is the case for the current implementation of ECM, 36 may be less reliable and more vulnerable to noise than estimates of partial correlations. 53 Further studies using alternative definitions of the connectivity matrices are needed.…”