A brain scan may someday be able to help identify cases of autism, a new study suggests. Currently, autism is diagnosed based on subjective evaluations of a child’s behavioral and developmental deficits, but researchers at Columbia say using brain scans may offer more objective indicators of the condition.
The researchers used functional MRI (fMRI) to study brain activity in 12 children with autism and 15 typical children, ranging in age from 4 to 17, while they listened to recordings of their parents talking. Researchers focused on activity in the brain regions that process hearing (primary auditory cortex) and language comprehension (superior temporal gyrus).
The brain scans showed no difference between the groups in brain activity in the region involved in hearing. But researchers noticed significantly greater activity in the language comprehension area in typical children than in kids with autism.
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Additional tests of another group of 27 age-matched autistic children were also included in the study. Using fMRI scans, researchers were able to identify autism correctly in 26 of them.
“Based on these initial findings, future studies using these or similar fMRI methods may result in an early and objective imaging indicator for autism,” Dr. Joy Hirsch of Columbia University said in a statement.
However, the study has significant limitations. First, the children in study were all school-age, which means the findings may not apply to younger children. Most children are diagnosed with autism around age 2, and it’s then — or earlier — that autism needs to be identified in order for kids to benefit from early intervention.
In addition, it’s not clear that brain scans could distinguish autism from other types of developmental delay, or whether they could identify autism spectrum disorders of differing severity.
The authors acknowledge that their findings are preliminary and that further work is needed to answer these questions. “This is not the diagnostic that you can package and send to all community health centers in the United States,” Hirsch told HealthDay. “This is an announcement that this can be done.”
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Autism affects about one in 110 American children, according to the Centers for Disease Control and Prevention, but recent studies suggest that the rate may be much higher and is certainly rising. Because the disorder is so widespread, researchers emphasize the need for earlier, objective diagnosis and better treatments.
The current study is published online in Radiology.