For children with autism spectrum disorder (ASD), early diagnosis is critical to allow for possible interventions at a time when the brain is most amenable to change. But that’s been tough to implement for a simple reason: the symptoms of ASD, such as communication difficulties, social deficits, and repetitive behaviors, often do not show up until a child turns 2 or even 3 years old.
Now, an NIH-funded research team has news that may pave the way for earlier detection of ASD. The key is to shift the diagnostic focus from how kids act to how their brains grow. In their brain imaging study, the researchers found that, compared to other children, youngsters with ASD showed unusually rapid brain growth from infancy to age 2. In fact, the growth differences were already evident by their first birthdays, well before autistic behaviors typically emerge.
Autism spectrum disorder includes a range of developmental conditions, such as autism and Asperger syndrome, that are characterized by challenges in social skills and communication. Scientists have long known that teens and adults with ASD have unusually large brain volumes. Researchers, including Heather Hazlett and Joseph Piven of the University of North Carolina, Chapel Hill, found more than a decade ago that those differences in brain size emerge by about age 2 . However, no one had ever visually tracked those developmental differences.
In the new study reported in Nature , Hazlett, Piven, and their colleagues set out to collect that visual evidence. They examined 106 infants at high risk of ASD, based on an older sibling with that diagnosis.