Research Of The Default Mode Network Based On The Fusion Of FMRI And DTI

Functional magnetic resonance imaging (fMRI) could reflecte the blood oxygenfunction of external stimulus or cognitive tasks about cerebral cortex and nucleioflaterleminiscus. Diffusion tensor imaging (DTI) can track out the structure of the fiberbundle connection. The fusion of this two images reveal the relationship of fiber tractsexactly and visually.Resting state of fMRI is a spontaneous activities of human brain. It reveals therelationship between different brain regions, and have a further research in brainmachinery. It is the default mode network (DMN) in the brain which is in the resting stateof metabolic activity to sustain the health of the human brain when several time correlationnetwork of brain regions.In this paper, independent component analysis (ICA) is applied to fMRI to theextraction of brain functional region. Combine canonical correlation analysis (CCA) withICA algorithm, and ICA with reference (ICA-R) algorithm are proposed to extract DMN asseed point to fusion DTI tracer fiber. The details are shown as follows:The CCA+ICA algorithm is proposed to locate DMN of resting state fMRI. Thisalgorithm use CCA firstly to reduce the spatial dimension of fMRI, then extract DMN ofthe resting state fMRIbased on ICA. Simulation and image data processing shown thatCCA+ICA algorithm can reduce the number of iterations effectively.Propose ICA with reference (ICA-R) algorithm to extract DMN of the restingstate fMRI. ICA-R algorithm regard part of priori information of the source signal asreference signal, can efficiently get a independent component closest with the referencesignal as expected source signal estimation under a certain measure. Simulation and imagedata processing shown that the proposed algorithm can improve efficiency effectively, andthe extracted DMN more accord with people’s physiological characteristics.The fusion of resting state fMRI and DTI to track fibers connection about DMN,obtain the fiber connection Internet. First use fMRI to extract the DMN as seed point,space registration with DTI images, then using genetic+simulated annealing algorithm to track the fiber connection between seed areas, get the DMN fiber connect Internet.