The Brain Unveiled

Technology Review ran a series of pictures and animations in The Brain Unveiled -  A new imaging method offers a spectacular view of neural structures based on diffusion spectrum imaging (DSI), a technique developed by Dr. Van Wedeen of the Massachusetts General Hospital. 

Standard magnetic resonance imaging (MRI) can create a three-dimensional picture of the brain, a massive improvement over two-dimension images.  However, the brain contains 'organs' (cortical fields and subcortical nucclii) that are not spatially distinct - in any one volume, multiple brain organs may overlap.  Much as CT scans reveal the the 3D structure obscured by overlapping in 2D X-rays, DSI combines 3D spatial information with additional dimensions about the diffusion of water molecules in the brain, which travel along the length of neural fibers.  Through extensive computational analysis, the intertwined structure of the brain can be 'unravelled'.  Visualization tools allow highlighting of neural pathways that pass through a slice or a specific region of the brain.  

Aside from the stunning images and animation, the research reveals a 'middle ground' between the relatively undifferentiated images previously available and the massive complexity of the 100 billion neurons and near-quadrillion synpases in the human brain.  Wedeen argues that the structure of the brain is made of about 400 organs connected by about a 1000 pathways, a manageable number for research and practical applications.  

For additional information, see the second section in Unraveling the Brain in Trauma and in Health that includes a 40 minute lecture by Van Wedeen.