Contributions
Abstract: 160
Type: Oral
Cognitive impairment is a common yet frequently overlooked clinical manifestation in multiple sclerosis (MS). Its neural substrate relies substantially on structural damage mainly through grey matter damage and white matter tracts disconnection. However, several recent studies have highlighted that functional connectivity (network-based brain organization) may reflect more accurately the pathophysiology of cognitive dysfunction, and could be a surrogate of cognitive impairment. Main large-scale brain networks involved in MS cognitive impairment are the default mode network (with the precuneus/posterior cingulate cortex as a major hub), the fronto-parietal network, the dorsal attentional network and the salience network.
One challenge to decrypt functional connectivity and its link with cognitive dysfunction is the heterogeneity of methodological techniques (fMRI at rest and during an activation task, magnetoencephalography) and metrics that can be computed from those signals: correlation matrices, information theory metrics or graph theory metrics.
Another challenge is the biological interpretation of functional connectivity changes reported in MS patients relative to controls, and associated with cognitive impairment. Increased functional connectivity could reflect adaptive (or maladaptive) mechanisms while decreased connectivity could be the consequence of structural damage. Longitudinal studies will be crucial to decipher the temporal evolution of functional connectivity during disease course, and the relationship between functional connectivity changes and clinical expression of symptoms like cognitive impairment.
Disclosure: Dr Louapre has received compensation for consulting services or speaker honoraria from Genzyme, Merck, Novartis and Biogen.
Abstract: 160
Type: Oral
Cognitive impairment is a common yet frequently overlooked clinical manifestation in multiple sclerosis (MS). Its neural substrate relies substantially on structural damage mainly through grey matter damage and white matter tracts disconnection. However, several recent studies have highlighted that functional connectivity (network-based brain organization) may reflect more accurately the pathophysiology of cognitive dysfunction, and could be a surrogate of cognitive impairment. Main large-scale brain networks involved in MS cognitive impairment are the default mode network (with the precuneus/posterior cingulate cortex as a major hub), the fronto-parietal network, the dorsal attentional network and the salience network.
One challenge to decrypt functional connectivity and its link with cognitive dysfunction is the heterogeneity of methodological techniques (fMRI at rest and during an activation task, magnetoencephalography) and metrics that can be computed from those signals: correlation matrices, information theory metrics or graph theory metrics.
Another challenge is the biological interpretation of functional connectivity changes reported in MS patients relative to controls, and associated with cognitive impairment. Increased functional connectivity could reflect adaptive (or maladaptive) mechanisms while decreased connectivity could be the consequence of structural damage. Longitudinal studies will be crucial to decipher the temporal evolution of functional connectivity during disease course, and the relationship between functional connectivity changes and clinical expression of symptoms like cognitive impairment.
Disclosure: Dr Louapre has received compensation for consulting services or speaker honoraria from Genzyme, Merck, Novartis and Biogen.