title: Is there a common neuroanatomical substrate of language deficit between autism spectrum disorder and specific language impairment?
abstract: Discussion of an overlap between specific language impairment (SLI) and autism spectrum disorder (ASD) is on going. The most intriguing overlap between both phenotypes is the similarity in the observed language deficits described in SLI and a subgroup of ASD with co-occurring linguistic impairment, ASD-LI. Examining whether a similar neuroanatomical substrate underlies this phenotypical linguistic overlap, we studied the white matter microstructural properties of the superior longitudinal fascicle (SLF) of 19 ASD-LI adolescents (mean age 13.8 ± 1.6 years) and 21 age-matched controls and compared them with 13 SLI children (mean age 10.1 ± 0.4 years) and 12 age-matched controls. A linguistic profile assessment and a diffusion tensor imaging analysis of the SLF were performed. Linguistic testing revealed a mixed receptive-expressive disorder profile in both groups, confirming their overlap at phenotypical level. At neuroanatomical level, no significant differences in mean SLF fractional anisotropy (FA) and mean SLF apparent diffusion coefficient values between ASD-LI participants and controls were seen. By contrast, the mean SLF FA was significantly reduced in the SLI children as compared with their controls. The observation of structural SLF disturbances in SLI but not in ASD-LI suggests the existence of a different neuroanatomical substrate for the language deficits in both disorders.
authors: Department of Pediatrics, University Hospitals of the Catholic University of Leuven, Leuven, Belgium.
authors: Judith S
authors: JS
authors: Verhoeven
authors: Nathalie
authors: N
authors: Rommel
authors: Elena
authors: E
authors: Prodi
authors: Alexander
authors: A
authors: Leemans
authors: Inge
authors: I
authors: Zink
authors: Ellen
authors: E
authors: Vandewalle
authors: Ilse
authors: I
authors: Noens
authors: Johan
authors: J
authors: Wagemans
authors: Jean
authors: J
authors: Steyaert
authors: Bart
authors: B
authors: Boets
authors: Ann
authors: A
authors: Van de Winckel
authors: Paul
authors: P
authors: De Cock
authors: Lieven
authors: L
authors: Lagae
authors: Stefan
authors: S
authors: Sunaert
mesh_terms: D000293:Adolescent; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006801:Humans; D007802:Language; D007806:Language Disorders / Q000503:physiopathology*; D008297:Male; D009415:Nerve Net / Q000503:physiopathology*; D009434:Neural Pathways / Q000503:physiopathology; D013702:Temporal Lobe / Q000503:physiopathology*