Skip to main content
Diffusion Tensor Imaging Provides Evidence of Possible Axonal Overconnectivity in Frontal Lobes in Autism Spectrum Disorder Toddlers.
- Author(s): Solso, Stephanie;
- Xu, Ronghui;
- Proudfoot, James;
- Hagler, Donald J;
- Campbell, Kathleen;
- Venkatraman, Vijay;
- Carter Barnes, Cynthia;
- Ahrens-Barbeau, Clelia;
- Pierce, Karen;
- Dale, Anders;
- Eyler, Lisa;
- Courchesne, Eric
- et al.
Published Web Locationhttps://doi.org/10.1016/j.biopsych.2015.06.029
BackgroundTheories of brain abnormality in autism spectrum disorder (ASD) have focused on underconnectivity as an explanation for social, language, and behavioral deficits but are based mainly on studies of older autistic children and adults.
MethodsIn 94 ASD and typical toddlers ages 1 to 4 years, we examined the microstructure (indexed by fractional anisotropy) and volume of axon pathways using in vivo diffusion tensor imaging of fronto-frontal, fronto-temporal, fronto-striatal, and fronto-amygdala axon pathways, as well as posterior contrast tracts. Differences between ASD and typical toddlers in the nature of the relationship of age to these measures were tested.
ResultsFrontal tracts in ASD toddlers displayed abnormal age-related changes with greater fractional anisotropy and volume than normal at younger ages but an overall slower than typical apparent rate of continued development across the span of years. Posterior cortical contrast tracts had few significant abnormalities.
ConclusionsFrontal fiber tracts displayed deviant early development and age-related changes that could underlie impaired brain functioning and impact social and communication behaviors in ASD.
For improved accessibility of PDF content, download the file to your device.