title: Fiber tracking of the frontal aslant tract and subcomponents of the arcuate fasciculus in 5-8-year-olds: Relation to speech and language function.
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.
authors.affiliation: Department of Psychology, Florida International University, Miami, FL, USA.
authors.forename: Iris
authors.initials: I
authors.lastname: Broce
authors.affiliation: Department of Radiology - Brain Institute, Nicklaus Children's Hospital, Miami, FL, USA.
authors.forename: Byron
authors.initials: B
authors.lastname: Bernal
authors.affiliation: Department of Radiology - Brain Institute, Nicklaus Children's Hospital, Miami, FL, USA.
authors.forename: Nolan
authors.initials: N
authors.lastname: Altman
authors.affiliation: Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec, Québec City, QC, Canada; Département de Réadaptation, Faculté de Médecine, Université Laval, Québec City, QC, Canada.
authors.forename: Pascale
authors.initials: P
authors.lastname: Tremblay
authors.affiliation: Department of Psychology, Florida International University, Miami, FL, USA. Electronic address: adick@fiu.edu.
authors.forename: Anthony Steven
authors.initials: AS
authors.lastname: Dick
mesh_terms: D016880:Anisotropy; D001921:Brain / Q000033:anatomy & histology* / Q000166:cytology / Q000502:physiology*; D001931:Brain Mapping; D002648:Child; D002675:Child, Preschool; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D013060:Speech / Q000502:physiology*
keywords: Arcuate fasciculus; Development; Diffusion tensor imaging; Frontal aslant tract; Superior longitudinal fasciculus; White matter