Hahn BS-12

At the Center for Complex Systems and Brain Sciences we are exploring state of the art imaging techniques to help understand structural changes in brain's diagnosed with (AD) Alzheimer's disease. Diffusion Tensor imaging (DTI) is a type of MRI that allows for identification of the long-range connections, namely the fiber tracts of the white matter in the human brain. 

Screen Shot 2013-03-03 at 12.45.35 PM

In essence, DTI is a noninvasive technique that images the brain in multiple directions to determine a diffusion tensor (a symmetric 3x3 matrix) at each volume element in space.  These tensors represent the probability of water diffusing in a given direction and allow for the differentiation between regions in the in the brain where the water diffusion is isotropic and the more interesting areas of high anisotropy that represent the long-range fibers. 

Screen Shot 2012-10-31 at 2.58.17 PM

Directions of high anisotropy are traced from voxel to voxel creating a map of tract bundles in space. The resulting tractography is filtered by region of interest to reveal major white matter pathways that correspond to known anatomy. Counting the traces that connect each region of interest along the anisotropy skeleton provides a quantitative representation of differences in structural connectivity that occur with AD. We use DTI to detect differences in the white matter skeleton of elderly humans with Alzheimer's disease (AD), an age-matched control group, and a group of adults aged 40-50 years. 

Continue to: 

Machine Perception and Cognitive Robotics Laboratory



MPCR Slides

MPCR Github

MPCR Facebook

MPCR Subreddit

WH 2013