Functional magnetic resonance imaging and cognition at the very early stage of MS.
Dysfunction of high controlled information processing is present in patients with multiple sclerosis (MS) right at the beginning of the disease. One hypothesis is that disruption of communication inside large-scale cortical networks, occurring as a consequence of white matter damage, may constitute the anatomical substrate of cognitive impairment at the very early stage of MS. Disturbance of interregional synchronization might be the main pathogenic factor in controlled information processing deficiency in early MS. Preliminary functional MRI studies (fMRI) have provided important clues to corroborate the connectivity hypotheses. First, brain connectivity assessed by fMRI has brought new data about the influence of diffuse white matter damage on connectivity efficiency inside large-scale networks. These studies have suggested that connectivity disturbances occur inside the working memory network in patients at the very early stage of MS and appear related to the extent of structural white matter damage. Also, fMRI studies have suggested that patients may partially compensate for connectivity impairment by a greater cognitive control. Such a compensatory mechanism could limit the determinant functional impact of diffuse white matter damage on high controlled information processing.
Audoin
Bertrand
B
Centre de Résonance Magnétique Biologique et Médicale, CRMBM-CNRS 6612, Faculté de Médecine, 27 bvd Jean Moulin, 13005 Marseille, France.
Au Duong
My Van
MV
Malikova
Irina
I
Confort-Gouny
Sylviane
S
Ibarrola
Danielle
D
Cozzone
Patrick J
PJ
Pelletier
Jean
J
Ranjeva
Jean-Philippe
JP
D017668:Age of Onset; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply* / Q000473:pathology; D003071:Cognition / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008570:Memory, Short-Term / Q000502:physiology; D009103:Multiple Sclerosis / Q000097:blood / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood
D010100:Oxygen