Using a technique he developed called diffusion spectrum magnetic resonance imaging (MRI), Wedeen traced the movement of water molecules along the intersections of brain fibers (the cellular projections that form the brain’s communication network), tracking the orientation of each fiber at each crossing.
“What emerged was astonishing,” Wedeen said. “What emerged was that the set of fibers that crossed a given fiber, invariably – and that’s a really strong invariably – look like mutually parallel fibers all coming in like the teeth of a comb and crossing it in one direction.”
Image from Van Wedeen, M.D., Martinos Center for Biomedical Imaging, Massachusetts General Hospital
“This is a detail of a diffusion spectrum MR image of rhesus monkey brain showing the sheet-like, three-dimensional structure of neural pathways that cross each other at right angles.”Other similar posts