Fiber tracking of the frontal aslant tract and subcomponents of the arcuate fasciculus in 5-8-year-olds: Relation to speech and language function

Brain Lang. 2015 Oct;149:66-76. doi: 10.1016/j.bandl.2015.06.006. Epub 2015 Jul 14.

Abstract

Long association cortical fiber pathways support developing networks for speech and language, but we do not have a clear understanding of how they develop in early childhood. Using diffusion-weighted imaging (DWI) we tracked the frontal aslant tract (FAT), arcuate fasciculus (AF), and AF segments (anterior, long, posterior) in 19 typical 5-8-year-olds, an age range in which significant improvement in speech and language function occurs. While the microstructural properties of the FAT and the right AF did not show age-related differences over the age range we investigated, the left AF evidenced increasing fractional anisotropy with age. Microstructural properties of the AF in both hemispheres, however, predicted receptive and expressive language. Length of the left FAT also predicted receptive language, which provides initial suggestion that this pathway is important for language development. These findings have implications for models of language development and for models of the neurobiology of language more broadly.

Keywords: Arcuate fasciculus; Development; Diffusion tensor imaging; Frontal aslant tract; Superior longitudinal fasciculus; White matter.

MeSH terms

  • Anisotropy
  • Brain / anatomy & histology*
  • Brain / cytology
  • Brain / physiology*
  • Brain Mapping
  • Child
  • Child, Preschool
  • Diffusion Tensor Imaging
  • Female
  • Humans
  • Male
  • Nerve Net / physiology*
  • Speech / physiology*