Monday, 28 July 2014

Neural network disruption

Tewarie P, Steenwijk MD, Tijms BM, Daams M, Balk LJ, Stam CJ, Uitdehaag BM, Polman CH, Geurts JJ, Barkhof F, Pouwels PJ, Vrenken H, Hillebrand A.Disruption of structural and functional networks in long-standing multiple sclerosis. Hum Brain Mapp. 2014 Jul 22. doi: 10.1002/hbm.22596. [Epub ahead of print]

Both gray matter atrophy and disruption of functional networks are important predictors for physical disability and cognitive impairment in multiple sclerosis (MS), yet their relationship is poorly understood. Graph theory provides a modality invariant framework to analyze patterns of gray matter morphology and functional coactivation. We investigated, how gray matter and functional networks were affected within the same MS sample and examined their interrelationship. Magnetic resonance imaging and magnetoencephalography (MEG) were performed in 102 MS patients and 42 healthy controls. Gray matter networks were computed at the group-level based on cortical thickness correlations between 78 regions across subjects. MEG functional networks were computed. In MS patients, we found a more regular network organization for structural covariance networks and for functional networks in the theta band (Delta (0.5-4Hz), Theta (4-8Hz), Alpha1 (8-11Hz), Alpha2 (11-14Hz, Beta1 (14-25Hz) and Beta2 (25-35Hz), whereas we found a more random network organization for functional networks in the alpha2 band. Correlation analysis revealed a positive association between covariation in thickness and functional connectivity in especially the theta band in MS patients, and these results could not be explained by simple regional gray matter thickness measurements. This study is a first multimodal graph analysis in a sample of MS patients, and our results suggest that a disruption of gray matter network topology is important to understand alterations in functional connectivity in MS as regional gray matter fails to take into account the inherent connectivity structure of the brain
Sometimes we simply don't have enough time to do our day job and do posts enough justice. It requires time to explain posts. How about this one?



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