Possible New Diagnostic Tool for Autism Spectrum Disorders

The results of a study from Children's Hospital Philadelphia may provide researchers with a new tool for the diagnosis of autism spectrum disorders.

The use of magnetoencephalography (MEG) to detect changes in a child’s ability to process language and sound may become a new tool for diagnosing autism spectrum disorders (ASD), researchers from the Children’s Hospital of Philadelphia report.

Study leader Timothy P.L. Roberts, Ph.D., vice chair of Radiology Research at Children's, and his fellow researchers found that children with ASD had an average delay of 11 milliseconds, or about 1/100 of a second, in their brain’s response to sound compared to the children without ASD. Among the children with ASD, the delay in response was similar for all, regardless of whether the children had language impairments.

"This delayed response suggests that the auditory system may be slower to develop and mature in children with ASDs," said Roberts. An 11-millisecond delay is brief, but it means, for instance, that a child with ASD, on hearing the word 'elephant' is still processing the 'el' sound while other children have moved on. The delays may cascade as a conversation progresses, and the child may lag behind typically developing peers."

The researchers used MEG to analyze the brains of 25 children with ASD, with a mean age of 10 years, in comparison to 17 age-matched, typically developing children. A previous study by Roberts and his team used MEG to “analyze the development of white matter in the brains of 26 typically developing children and adolescents,” which showed that “normal age-related development of greater myelination corresponds with faster auditory responses in the brain.” According to Roberts, the results of the earlier study may correlate to the team’s new findings.

"The delayed auditory response that we find in children with ASDs may reflect delayed white matter development in these children," he said.

According to Roberts, the next step for the team will be to refine the imaging techniques to “determine that their biomarker is specific to ASDs, and will investigate other MEG patterns found in children with ASDs in addition to auditory delays.”

The study was also published in Autism Research.