Abnormal white matter integrity in young children with autism

Abstract

This study investigated white matter integrity in young children with autism using diffusion tensor imaging (DTI). Twenty-two children with autism, mean age 3:2 years, and 32 controls, mean age 3:4 years, participated in the study. Tract-based spatial statistics (TBSS) revealed white matter abnormalities in several distinct clusters within the genu and body of the corpus callosum (CC), left superior longitudinal fasciculus (SLF) and right and left cingulum (Cg). TBSS-VOIs analysis was performed in the clusters where differences in fractional anisotropy (FA) were detected to investigate the relationship between changes in FA and diffusivity indices. In all VOIs, increase in FA was caused by a decrease in radial diffusivity (Dr), while no changes in axial diffusivity (Da) or mean diffusivity (MD) were observed. Tractography analysis was applied to further study the CC, SLF, and Cg. Witelson parcellation scheme was used for the CC. Significant increase in FA was seen in children with autism in the mid-body of the CC as well as in the left Cg. It is suggested that such abnormal white matter integrity in young children with autism may adversely affect connectivity between different brain regions and may be linked to some of the behavioral impairments apparent in autism.

The Relation Between ADHD and Cognitive Profiles of Children with NF1

“…In regard to weaknesses on tasks measuring attentional control, working memory, and cognitive processing and response speed, the NF1 IQ profile is in keeping with research on other developmental disabilities, showing a consistent susceptibility to disruption in attention, working memory, and cognitive efficiency functions (Oliveras-Rentas et al 2011;Mayes and Calhoun 2006). These types of neuropsychological deficits are linked to disruptions in white matter tracts, which are particularly vulnerable due to their protracted developmental trajectory (e.g., Barnea-Goraly et al 2005) and are commonly seen in developmental disabilities including NF1, ADHD, and autism spectrum disorders (ASD) (e.g., Lawrence et al 2013;Weinstein et al 2011;Cutting et al 2002). From this perspective, the IQ profile seen in children with NF1 reflects similar vulnerabilities as those observed in other developmental disabilities, such as ADHD and ASD.…”

Elevated Mean Diffusivity in the Left Hemisphere Superior Longitudinal Fasciculus in Autism Spectrum Disorders Increases with More Profound Language Impairment

“…6,7,[25][26][27][28][29][30][31][32] Lee et al 33 also demonstrated an increase in MD in the bilateral white matter of the superior temporal gyrus and right temporal stem in patients with high-functioning autism compared with age-matched TD. The authors also found an overall reduction in , 2 , 3 and attributed the findings along these pathways, critically involved in language and social cognition, to microstructural disorganization.…”

Differences in the right inferior longitudinal fasciculus but no general disruption of white matter tracts in children with autism spectrum disorder

“…Ten studies gathered imaging data while some participants were under general anesthesia and an additional two while participants were sleeping naturally, presumably reducing head motion. Of these studies, however, only one imaged both ASD and typical groups under anesthesia (21). Indeed, one study that imaged participants with ASD under anesthesia and typical participants while asleep concluded that at least some of their group differences were likely caused by differences in motion (22).…”