Figure 3.

Delineation of known fiber pathways using submillimeter resolution MSMT-CSD probabilistic tractography demonstrated for the flexible surface coil DWI of one representative participant, superimposed on the DWI-derived fractional anisotropy map. (a) Fiber tracks corresponding to the optic radiation and the posterior tail of the splenium of the corpus callosum tracts. (b) The short fiber connections of the occipital lobe were mapped using histology by Sachs (reproduced from Sachs 1892). Fiber tracks corresponding to (c-i) the VOF and (c-ii) fibers connecting the upper and lower banks of the calcarine sulcus. (c-iii) The short U-shaped fiber tracks mapped by user-defined streamline length and curvature thresholds (see Supplementary Video 5 for a map of the short connections obtained from a 32-channel coil DWI acquisition). U-shaped streamlines penetrated the cortical GM at the gyri. U-shaped streamlines connecting directly adjacent gyral GM are shown in the inset of c-iii. The underlying fODF distribution shows intracortical radial fibers. A, S, and L: anterior, superior, and left, respectively.