Adult males with autism spectrum disorder (ASD) have subtle differences in their brain activity, which may explain why certain symptoms continue into adulthood for some with the disorder, according to a team of researchers from King's College London. Some of these symptoms include impaired social interactions and reciprocal understanding, repetitive behavior and a narrow range of interests.

The study used a novel brain imaging method called Diffusion Tensor Imaging (DTI), which is a type of magnetic resonance imaging (MRI), in order to identify altered brain connections in people with ASD. The team compared the white matter networks, which ensure the connection of various brain regions and enable communication between them, of 61 adults with ASD and 61 controls.

The results showed that men with ASD possessed altered brain connections in the frontal lobe, which is the part of the brain involved in language development and social interaction skills. In particular, they showed altered developed of white matter connections in the left hemisphere's arcuate bundle, which is a region involved in language. Additionally, those who had "delayed echolia," a common symptom of ASD that manifests in the repetition of words and sentences, showed particularly severe alterations in this area.

"White matter provides key insights which allow us to paint a precise picture of how different parts of the brain develop during critical periods in childhood," Marco Catini, who participated in the research, said in a press release. "We found subtle brain differences in men who at a very young age had severe problems with communication and social interaction. The differences appear to remain even if they have somehow learned to cope with these difficulties in adult life."

"Our study did not include women and children, so it would be interesting to explore whether similar differences exist within these groups," Catini added. "For example, research has shown that women appear more resilient than men when it comes to autism, so it will be important if this is explained biologically in their brain development."

The findings were published in the Jan. 29 issue of Brain.