Brain Scans May Help Detect Autism
Study Shows Functional MRI Images Differ Between Autistic Brain, Typical Brain
May 31, 2011 -- Brain scans known as functional MRIs may someday help in diagnosing autism, according to new research.
''We know now it is possible to objectively differentiate the autistic brain from the typical brain using a functional MRI imaging technique," says researcher Joy Hirsch, PhD, professor of neuroscience and director of the Functional MRI Research Center at Columbia University Medical Center, New York.
However, the research is in its early stages and needs to be duplicated in larger studies, she tells WebMD. "It's an important advance, but it's not there yet," she says.
An expert who reviewed the findings tells WebMD it's more likely the scans could be used to monitor therapy for children with autism, rather than help in diagnosing autism.
Autism spectrum disorders are marked by impaired language and repetitive behaviors. They now affect up to one in 110 children, according to the CDC. The study is published online in Radiology.
Functional MRI for Autism Diagnosis: Study Details
Hirsch and her team set out to document language impairment in autistic children by using the scans.
"The idea of the study was to determine if functional imaging, which looks at both structure and function of the brain, could provide a diagnostic indicator of autism," she says.
Currently, diagnosing autism is done subjectively, Hirsch says. Parents and doctors note that a child misses important developmental milestones in language and other areas.
The researchers looked at 15 typically developing children and 12 children diagnosed with autism who had language impairment.
While the scan was being done, Hirsch says, "we had them listen to narratives that were recorded by their parents." The scans then measured the brain activity as the children listened to the narratives and encoded speech.
"We hypothesized that the autistic children would encode the language narrative less efficiently than the normal population," Hirsch tells WebMD.
They focused on two brain regions -- the primary auditory cortex, which processes sound information, and an area associated with sentence comprehension, the superior temporal gyrus (STG).
"The two groups did not differ in the response in the primary auditory cortex," Hirsch says. However, the activation within the STG was greater for the typically developing children than the autistic children.