WMTI (red), DTI (blue), and DKI (green) metrics reflect ontogeny and age-related changes in white matter (N = 54). (A) Box plots (whiskers = 5th, 95th percentiles) of metric values in the corpus callosum and other tract ROI. (B) Scatterplots and linear regression lines illustrating the main findings per metric (y-axis) by age (x-axis). Abbreviations: ASSN, association tracts; AWF, axonal water fraction; BODY, body; De,⊥, extraaxonal diffusivity in the radial direction; DTI, diffusion tensor imaging; DKI, diffusional kurtosis imaging; FA, fractional anisotropy; GENU, genu; LIMB, limbic tracts; MD, mean diffusivity; MK, mean kurtosis; PROJ, projection tracts; ROI, region-of-interest; SPLEN, splenium; WMTI, white matter tract integrity. *p < 0.01. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)