Individual Differences in White Matter Microstructure in the Healthy Brain

White matter pathways play an important role in the human brain by connecting spatially separated areas of the CNS and enabling rapid and efficient information exchange. Recent developments in MRI, such as diffusion imaging, have allowed their structural properties to be probed in vivo. While at first these methods were only sensitive enough to reveal structural differences in white matter pathways between different populations, they are now sensitive enough to expose inter-individual differences within relatively homogeneous groups. This chapter discusses the evidence for the behavioral relevance of these differences in white matter microstructure. White matter microstructure has been found to be associated with a wide range of human behavior, such as simple motor performance, cognitive abilities, and complex linguistic faculties. While individual differences in white matter microstructure in the healthy brain might be potentially related to genetic factors, this chapter raises the intriguing question of whether the structural differences are the results of experience. © 2014 Elsevier Inc. All rights reserved.