WINSTON-SALEM, N.C. — A brain-based test being researched by Wake Forest Baptist Health scientists may represent a key method for diagnosing autism.
The research team said it was able to measure the response of autistic children to different environmental cues by imaging a specific part of the brain “involved in assigning value to social interactions.”
The team used functional magnetic resonance imaging (fMRI) in the research.
The findings have been published online in the journal Biological Psychology.
“Right now, a two- to four-hour session by a qualified clinician is required to diagnose autism, and ultimately it is a subjective assessment based on their experience,” said the study’s principal investigator, Kenneth Kishida. He is assistant professor of physiology and pharmacology at Wake Forest School of Medicine.
“Our test would be a rapid, objective measurement of the brain to determine if the child responds normally to social stimulus vs. non-social stimulus, in essence a biomarker for autism.”
Autism spectrum disorder (ASD) is a developmental disorder that affects communication and interaction with other people. The National Institutes of Health estimates that 1 in 60 U.S. children are autistic.
The study included 40 participants ranging in age from 6 to 18; 12 had ASD and 28 were identified as “typically developing.”
Participants were scanned in an fMRI while viewing eight images of either people or objects, each one multiple times.
Included were two self-selected pictures of a favorite person and object from each participant. The other six were standardized images of three faces and three objects, each representing pleasant, neutral or unpleasant aspects from a data base widely used in psychological experiments.
After completing the 12- to 15-minute MRI scan, the children viewed the same set of images on a computer screen and ranked them in order from pleasant to unpleasant with a self-assessing sliding scale. In addition, pairs of images were viewed and ranked as to which one they liked better.
According to the study, the average response was significantly lower in the ASD group than in the typically developing group. Kishida said that using images as a single stimulus to capture 30 seconds of fMRI data was sufficient to differentiate the groups.
“How the brain responded to these pictures is consistent with our hypothesis that the brains of children with autism do not encode the value of social exchange in the same way as typically developing children,” he said.
“We envision a test for autism in which a child could simply get into a scanner, be shown a set of pictures and within 30 seconds have an objective measurement that indicates if their brain responds normally to social stimulus and non-social stimuli.”
Kishida’s team plans to do follow-up studies to see if additional areas of the brain are involved in the different facets of the disorder to help personalize treatments.