Altered functional connectivity related to white matter changes inside the working memory network at the very early stage of MS.

My-Van Au Duong; Bertrand Audoin; Kader Boulanouar; Daniella Ibarrola; Irina Malikova; Sylrane Confort-Gouny; Pierre Celsis; Jean Pelletier; Patrick J Cozzone; Jean-Philippe Ranjeva

doi:10.1038/sj.jcbfm.9600122

PubMed · 15843789

Altered functional connectivity related to white matter changes inside the working memory network at the very early stage of MS.

My-Van Au Duong·Bertrand Audoin·Kader Boulanouar·Daniella Ibarrola·Irina Malikova·Sylrane Confort-Gouny·Pierre Celsis·Jean Pelletier·Patrick J Cozzone·Jean-Philippe Ranjeva

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Abstract

Functional magnetic resonance imaging (fMRI) using paced auditory serial addition test (PASAT) as paradigm was used to study the functional connectivity in 18 patients at the very early stage of multiple sclerosis (MS) compared with 18 controls, to determine the existence of circuitry disturbance inside the working memory network and its relationship with white matter abnormalities assessed by conventional MRI and magnetization transfer ratio (MTR) imaging. The left BA 45/46 was selected as the seed region to compute correlation maps with other brain regions. After obtaining the correlation map for each subject, between-group comparisons were performed using random effect procedure. Compared with controls, patients did not show any greater functional connectivity between left BA 45/46 and other regions during PASAT. In contrast, decrease in functional connectivity was observed in patients between left BA 45/46 and left BA 9, right BA 3, and the anterior cingulate cortex (BA 24). In patients, no correlations were found between altered functional connectivity and clinical data. However, functional connectivity observed between left BA 45/46 and BA 24 in patients was correlated with the MTR of normal appearing white matter, and with brain T(2) lesion load. Altered functional connectivity is present inside the working memory network of patients at the very early stage of MS and is related to the extent of diffuse white matter changes.

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Acoustic Stimulation Adult Brain Brain Mapping Case-Control Studies Humans Magnetic Resonance Imaging Memory Multiple Sclerosis Nerve Fibers, Myelinated Nerve Net Journal Article Research Support, Non-U.S. Gov't

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My-Van Au Duong, Bertrand Audoin, Kader Boulanouar, Daniella Ibarrola, Irina Malikova, Sylrane Confort-Gouny, Pierre Celsis, Jean Pelletier, Patrick J Cozzone, Jean-Philippe Ranjeva. 2005. Altered functional connectivity related to white matter changes inside the working memory network at the very early stage of MS.. https://doi.org/10.1038/sj.jcbfm.9600122

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