Autism spectrum disorder affects an estimated one in 68 children in the U.S. Early detection is important, but children typically can’t be diagnosed until after the age of two, when they start exhibiting symptoms such as repetitive behavior and difficulty interacting with others.
By this point, however, fundamental developments in the brain have already occurred. But what if doctors could diagnosis the condition in infancy, when the brain is more malleable?
A new study, published in the journal Nature, suggests this might be possible. By analyzing brain scans of more than 150 infants — two thirds of whom had a brother or sister with autism, putting them at a much higher risk of developing the condition— the researchers pinpointed autism biomarkers. Most notable was a rapid expansion of the brain’s surface area between the ages of six to 12 months, and rapid increase in volume between the ages of 12 to 24 months. Put simply, between the ages of one and two, “their brains grew too fast, compared to controls,” says the report’s senior author, Joe Piven.
After feeding the scans of the babies at six, 12, and 24 months into an algorithm, the researchers were able to identify, with an 80 percent degree of accuracy, which babies would subsequently receive an autism diagnosis. This is important, says co-author Heather Cody Hazlett, a psychologist at the Carolina Institute of Developmental Disabilities, because behavioral cues don’t work very well for infants: Before the age of two, children who go on to develop autism behave almost identically to those who do not.
By examining the scans, however, “we were able to see changes in the brain before the symptoms emerged,” says Piven.
If the study’s results are replicated, it could have a number of implications for autism treatment, including the development of new behavioral therapies that work to alter the brain development of at-risk infants. Using information collected from the study, the researchers are also hoping to determine how certain environmental factors, such as air pollution and exposure to toxic metals, affects the likelihood a baby will go on to develop autism
Autism rates have sharply increased since the early 1990s, which helped encourage the now thoroughly debunked (although still hotly-contested) theory that vaccines can cause the disorder. But most experts pin autism’s rise, at least in part, to shifting diagnostic measures and an increase in awareness.