Diffusion MRI

Diffusion MRI provides a unique method for examining the brain in vivo. It is used increasingly in imaging neuroscience due to its ability to generate quantifiable indices of tissue integrity. To introduce this method, this chapter describes how diffusion is measured, what these measures can tell us about white matter microstructure, and some of the analysis techniques adopted for this purpose. With a focus on diffusion tensor imaging (DTI), we then contextualize the method by reviewing some of the contributions that DTI studies have made to the understanding of white matter changes in health, across the lifespan, and in disease, across a range of neurological and psychiatric illnesses.