The Rate of Reduction in Cerebral Cortical Diffusion Anisotropy Reflects the Rate of Brain Development

Lindsey A. Leigland¹, Christopher D. Kroenke¹

Throughout the human gestational period, morphological differentiation of cortical neurons and glial cells cause water diffusion anisotropy within the developing cerebral cortex to decrease with age. Herein, the loss of cortical fractional anisotropy (FA) reported by several research groups in five different species is referenced against a systematic comparative study of the timing of several milestones in brain development. It is found that, when the loss of cortical FA is approximated as an exponential decay with age, the time constant reflecting the rate of FA change is in agreement with independent estimates of the rate in which developmental events occur.