A new study involving MEG (magnetoencephalography) as a diagnostic tool discovered that certain “signatures of autism” may show a delay in processing individual sounds. Brain activity may become a biomarker, a toll that may help improve classification of the disorder and aid in autism treatment and therapy planning.

More specifically, the speed an autistic child’s brain processes sounds as gauged by magnetoencephalography may offer crucial information about the severity of the condition, researchers reported at the Radiological Society of North America meeting. The research used a helmet that looks like a hair dryer to study the brain waves of 64 children, 30 of which had been diagnosed with autism. The participants wore headphones and listened to a series of sounds. Children with autism spectrum disorder had an average delay of about 20 milliseconds compared with normal subjects.

The researchers hope this technique could be used to help diagnose autism in children as young as age 1. This would allow an early start on behavioral therapy necessary to help these children learn to communicate.

“We tend to speak at four syllables per second, if an autistic brain is slow in processing a change in a syllable…it could easily get to the point of being overloaded,” explained Timothy Roberts, the study’s lead author and vice chairman of research at Children’s Hospital of Philadelphia. He said the findings support the theory that autism is a “disorder of connectivity of the brain.”

Magnetoencephalography technology is usually used to map brain tumours and evaluate epilepsy. The Children’s Hospital of Philadelphia has the only MEG unit dedicated to pediatric care. MEG measures magnetic fields generated by electrical currents in brain nerve cells, and records brain activity in real time.

Autism is a disability which typically appears during the first years of life and it affects the child’s ability to communicate and interact with others. There is no single cause of autism, a disorder involving poor verbal communication, repetitive behaviors such as head-banging, and avoidance of physical or eye contact, and most doctors believe is no cure, but sometimes medications can lessen symptoms. It is estimated that one in every 150 American children have the condition, which tends to affect mostly boys. The condition is usually diagnosed after the child is two years of age.

Regarding the causes that trigger autism, most doctors agree there is a genetic link. Lack of vitamin D caused by insufficient time in the sun has been also associated with the disease. Studies have shown that environmental factors may have an impact on the disease. The researchers hope the findings may also provide more clues to the causes of autism and may help determine what is hereditary and what is environmental in the cause.

“We hope that in the future, these signatures will also be revealed in the infant brain to help diagnose autism and allow earlier intervention,” said researcher Timothy Roberts. Dr. Roberts said magnetoencephalography could possibly lead to therapeutic approaches such as slowing speech when communicating with autistic children.

Other researchers, who were not involved in the study, said the results were preliminary, but with promise. However, more studies are needed to confirm the findings.