Figure 2.

Following data quality assessment and preprocessing, native space neurite density index (NDI), orientation dispersion index (ODI), myelin volume fraction (VF_m), and quantitative ihMT (qihMT) maps (a) were normalized to subject fractional anisotropy (FA) maps in T1 space (b), resulting in anatomically relevant measure maps and allowing g‐ratio computation (c). Meanwhile, whole‐brain tractography via constrained spherical deconvolution (CSD) (d) and semiautomated tractography (e) was conducted in ExploreDTI to identify major white matter tracts in each participant's brain (f). Finally, mean FA, mean diffusivity (MD), NDI, ODI, qihMT, VF_m, and g‐ratio were calculated globally and by averaging across voxels in each tract (g) [Color figure can be viewed at http://wileyonlinelibrary.com]