brainGeek

DTI color map, axial view. Red signifies diffusion occurring laterally; blue is superior/inferior; and green is anterior/posterior.

Fractional anisotropy (FA) map overlaid on a structural scan.  I acquired the FA data from a diffusion tensor imaging (DTI) scan.  Basically, it helps you image the direction and magnitude of water diffusion in brain tissue.  Water in heavily myelinated areas (neurons surrounded by a sheath of fatty tissue) travels more in one direction (it’s anisotropic); this tends to be white matter.  Water in less “insulated” areas tends to diffuse out in multiple directions (it’s isotropic); this tends to be grey matter.  So, in the simplest terms, DTI gives you an idea of where nerve tracts are in the brain.