The brains of children with autism exhibit more connections than the brains of typically developing children, according to two new studies published in the journal Cell Reports. Furthermore, the brains of those with the most severe social problems are also the most hyper-connected.
The findings from the independent studies challenge the currently accepted idea that autistic brains are lacking in neural connections.
Autism spectrum disorder is a neurodevelopmental condition affecting nearly 1 in 88 children. The findings could pave the way toward novel treatment therapies and new ways to detect autism early, according to the researchers.
“Our study addresses one of the hottest open questions in autism research,” said Kaustubh Supekar, Ph.D., of Stanford University School of Medicine. He and his colleague Vinod Menon, Ph.D., conducted their study in an attempt to understand whole-brain connectivity in children.
“Using one of the largest and most heterogeneous pediatric functional neuro-imaging datasets to date, we demonstrate that the brains of children with autism are hyper-connected in ways that are related to the severity of social impairment exhibited by these children,” the researchers wrote.
In the second study, Ralph-Axel Müller, Ph.D., and a team from San Diego State University investigated the neighboring brain regions and found an unusual increase in connections in adolescents with a diagnosis of autism spectrum disorder.
This over-connection—observed particularly in the regions of the brain that control vision — was also linked to symptom severity.
“Our findings support the special status of the visual system in children with heavier symptom load,” Müller said, adding that all of the subjects in his study were considered “high-functioning” with IQs above 70. He believes that one day measures of local connectivity in the cortex might be used as an aid in diagnosis, which today is based solely on behavior.
For Supekar and Menon, these new findings raise the intriguing possibility that epilepsy drugs might be used to treat autism.
“Our findings suggest that the imbalance of excitation and inhibition in the local brain circuits could engender cognitive and behavioral deficits observed in autism,” Menon said.
This imbalance shows up in epilepsy as well, which might explain why children with autism so often suffer from epilepsy too.
“Drawing from these observations, it might not be too far-fetched to speculate that the existing drugs used to treat epilepsy may be potentially useful in treating autism,” Supekar said.
Source: Cell Reports