Timothy Roberts of Children's Hospital of Philadelphia said abnormalities in auditory and language processing may be evaluated in children with autism spectrum disorder by using magnetoencephalography.

"Using magnetoencephalography, we can record the tiny magnetic fields associated with electrical brain activity," Roberts said in a statement. "Recorded brain waves change with every sensation, thought and activity. It's like watching a movie of the brain in real time."

For a magnetoencephalography exam, a helmet that houses magnetic detectors and looks similar to an old-fashioned hair dryer is lowered over the patient's head while the patient remains in a seated position. The helmet analyzes electrical currents from the brain.

Sixty-four patients, ages 6 to 15, with a diagnosis of autism spectrum disorder were evaluated with magnetoencephalography.

The findings showed that in the children with autism there was a fraction of a second delay in the brain's response while processing the rapid succession sounds and the unusual streams, giving researchers an insight into the dysfunction of the auditory processing system in autistic children.

The study was presented at the annual meeting of the Radiological Society of North America in Chicago.