We evaluated brain white matter pathways associated with language processing in 37 children with specific language impairment aged 6-12 years and 34 controls, matched for age, sex and handedness. Arcuate fascicle (AF), inferior fronto-occipital fascicle (IFOF), inferior longitudinal fascicle (ILF) and uncinate fascicle (UF) were identified using magnetic resonance diffusion tensor imaging (DTI).
Diffusivity parameters and volume of the tracts were compared between the SLI and control group. Children with SLI showed decreased fractional anisotropy in all investigated tracts, increased mean diffusivity and radial diffusivity component in arcuate fascicle bilaterally, left IFOF and left ILF.
Further, bilaterally increased volume of the ILF in children with SLI was found. We confirmed previous findings indicating deficient connectivity of the arcuate fascicle and as a novel finding, demonstrate abnormal development of the ventral language stream in patients with SLI.