The children who speak least — or not at all — are rarely represented in cutting-edge brain imaging research on autism spectrum disorder (ASD). Researchers at The Children’s Hospital of Philadelphia aim to change that with a new study enrolling children with ASD who are minimally verbal or nonverbal.

“This is really an underserved community who have not been given the opportunity to participate in research,” said Timothy Roberts, PhD, vice chair of research in the Department of Radiology at CHOP and a professor of Radiology at the Perelman School of Medicine at the University of Pennsylvania. “More importantly, the results of the research are not directly applicable to them, so even if we developed a drug for ASD impairments led by our biomarkers, we wouldn’t know if this treatment really was good for individuals with ASD with more limited verbal and cognitive ability.”

Dr. Roberts and colleagues from CHOP’s Center for Autism Research want to know whether certain aspects of neural rhythms and timing of neural firing that they found to be characteristic of ASD in previous studies, using noninvasive brain imaging called magnetoencephalography (MEG), are indeed common across the spectrum.

“When neural activity is happening, it produces electrical and magnetic fields,” said J. Christopher Edgar, PhD, a co-leader of the study and a clinical neuropsychologist and brain imaging researcher in the Department of Radiology at CHOP. “We use this machine to measure the magnetic field. We do that to look at brain function.”

The neural biomarkers that Dr. Edgar and Dr. Roberts have found correlate with the level of clinical impairment in the children they have studied to date, particularly in the realm of language ability.

“There is a scientific question: Does this correlation extend into this nonverbal and minimally verbal population in a continuous way, or is it a separate disorder?” Dr. Roberts said. “I suppose a fundamental question is: Is the autism spectrum continuous or discrete in terms of these brain markers?”