Diffusion-weighted MRI in assessment and analysis of structural connectome of the human brain

S.I. Kartashov - Post-graduate Student, Research-Engineer of Laboratory of Cognitive Brain Function Neurovisualisation, Kurchatov-s complex of NBICS-technologies, National Research Centre «Kurchatov institute» (Moscow). E-mail: sikartashov@gmail.com

V.L. Ushakov - Ph.D. (Biol.), Laboratory of Cognitive Brain Function Methods of diffusion MRI are widely used throughout the world. Developers make a large number of software products for the processing and analysis of relevant data.

For visualization of brain regions involved in solving any our action we usualy use Functional magnetic resonance imaging data (fMRI). This method is sensitive to slight changes in blood flow (concentration changes in oxy- and deoxyhemoglobin in blood). To assess the structural connectivity areas of the brain we use diffusion-weighted.

Other method, that use diffusion data in visualisation of active areas of the brain called functional tractography. This method aims to identify paths in the white matter of the brain which become active when the subject perform any action [1]. According to the current hypothesis, the transmission signal along the active tract, in connection with increasing concentration of potassium ions in the extracellular space, glial cells increase in volume, thus making it difficult for the local liquor permeability [2]. This means that the diffusion coefficient varies along the path. Based on the GLM model for the tactile task diffusion coefficients at rest and during the «activation» were compared. This will highlight the motor path along which significantly changed diffusion. Thus the process was actually judged transmission signal from one region of the brain to another by fibers white solid.

This will result in an assessment obtained by the diffusion data. And compare the results of functional MRI tractography and functional to assess the validity of the data.

This work was supported by grant RSF.