Signs of autism seen in brain at 6 months

UNC-CHAPEL HILL (US) — A new study has discovered significant differences in brain development between infants who go on to develop autism and those who do not.

As early as 6 months of age, imaging scans show major changes take place in the brains of children who were later diagnosed with autism, according to researchers at the University of North Carolina at Chapel Hill.

Follow up scans on the toddlers through to 24 months old continued to find ongoing differences.

“It’s a promising finding,” says Jason J. Wolff, study lead author and a postdoctoral fellow at UNC. “At this point, it’s a preliminary albeit great first step towards thinking about developing a biomarker for risk in advance of our current ability to diagnose autism.”


The study also suggests, Wolff notes, that autism does not appear suddenly in young children, but instead develops over time during infancy. This raises the possibility “that we may be able to interrupt that process with targeted intervention.”

The findings are published by the American Journal of Psychiatry. They are the latest results from the ongoing Infant Brain Imaging Study (IBIS) Network, which is funded by the National Institutes of Health and headquartered at UNC.

Researchers followed 92 children considered at high risk of developing autism because they have older siblings with the condition. Using brain imaging scans, scientists measured development of the infants’ white matter fiber tracts—pathways that connect brain regions. They found significant differences in 12 of the 15 pathways examined.

Furthermore, infants who later developed autism spectrum disorders (30 percent of the group) had elevated white matter measurements at 6 months of age, but then experienced slower change over time; by 24 months, they had lower measures than infants without autism.

“This evidence, which implicates multiple fiber pathways, suggests that autism is a whole-brain phenomenon not isolated to any particular brain region,” Wolff says.

In addition to NIH funding, the IBIS Network receives support from Autism Speaks and the Simons Foundation Autism Research Initiative.

Eighteen researchers are listed as co-authors of the study. Other institutions and organizations that took part in the study include the University of Utah, Washington University in St. Louis, University of Washington, McGill University, Children’s Hospital of Philadelphia, and the University of Alberta.

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