title: Pediatric traumatic brain injury: language outcomes and their relationship to the arcuate fasciculus.
abstract: Pediatric traumatic brain injury (TBI) may result in long-lasting language impairments alongside dysarthria, a motor-speech disorder. Whether this co-morbidity is due to the functional links between speech and language networks, or to widespread damage affecting both motor and language tracts, remains unknown. Here we investigated language function and diffusion metrics (using diffusion-weighted tractography) within the arcuate fasciculus, the uncinate fasciculus, and the corpus callosum in 32 young people after TBI (approximately half with dysarthria) and age-matched healthy controls (n=17). Only participants with dysarthria showed impairments in language, affecting sentence formulation and semantic association. In the whole TBI group, sentence formulation was best predicted by combined corpus callosum and left arcuate volumes, suggesting this "dual blow" seriously reduces the potential for functional reorganisation. Word comprehension was predicted by fractional anisotropy in the right arcuate. The co-morbidity between dysarthria and language deficits therefore seems to be the consequence of multiple tract damage.
authors.affiliation: Developmental Cognitive Neuroscience Unit, University College London, Institute of Child Health, London, United Kingdom. Electronic address: f.liegeois@ucl.ac.uk.
authors.forename: Frédérique J
authors.initials: FJ
authors.lastname: Liégeois
authors.forename: Kate
authors.initials: K
authors.lastname: Mahony
authors.forename: Alan
authors.initials: A
authors.lastname: Connelly
authors.forename: Lauren
authors.initials: L
authors.lastname: Pigdon
authors.forename: Jacques-Donald
authors.initials: JD
authors.lastname: Tournier
authors.forename: Angela T
authors.initials: AT
authors.lastname: Morgan
mesh_terms: D000293:Adolescent; D001921:Brain / Q000503:physiopathology*; D001930:Brain Injuries / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D056324:Diffusion Tensor Imaging; D004401:Dysarthria / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007802:Language; D008297:Male
keywords: Arcuate fasciculus.; Dysarthria; Expressive language; Pediatric brain injury; Tractography