The study was conducted by Christine Wu Nordahl, an assistant professor in the department of psychiatry and behavioral sciences at the University of California, Davis MIND Institute, and her team.
The research included 139 young children with an autism spectrum disorder. Researchers used MRI scans in order to examine the brain structures of 112 boys and 27 girls with autism and 53 boys and 29 girls without autism. All participants of the study were between 3 and 5 years old. The researchers were interested in the way that nerve fibers manifested from the corpus callosum to other regions of the brain.
The result of the study showed that even though all autism patients have fiber bundles that are different from those in brains of other people, the nature of the differences varies according to the gender.
The study revealed that boys with autism had smaller callosal regions that were connected with the part of the brain which regulates emotions and decision-making also known as the orbitofrontal cortex. On the other hand, girls with autism had smaller callosal regions connected with the brain region that is in control* of planning and executing tasks, also known as the anterior frontal cortex.
Understanding these differences can improve* the way how autism is diagnosed and treated in boys and girls. The lead researcher, Christine Wu Nordahl said: “We don’t yet know enough about females with autism because most research studies do not have equal numbers of females and males with autism in their samples.”
Professor Nordahl admitted that the number of samples was limited and stressed the importance for conducting more researches which will include more girls.
According to the United States’ Centers for Disease Control* and Prevention, one in 68 children in America is affected by autism spectrum disorders. Additionally, this disorder is five times more common in boys than girls.
However, Andrea Roberts, a research associate at Harvard School of Public Health emphasized the importance of the study’s results: “Researchers have known for a long time that there are big sex differences in the prevalence of autism, and there have been many ideas of why that might be. So far, research hasn’t really backed up any of them, but there’s got to be something going on biologically to explain that.”
The study showed physical differences in brain of boys and girls with autism and the results of the research are published in the May 12, 2015 issue of the journal Molecular Differences.
The new issue of the journal also published the article about exploring “female protective effect”. The notion declares that female brain is protected from developing autism which would explain why the number of boys with autism is significantly higher than number of girls affected by disorder. However, after analyzing genes of 4,500 families, researchers concluded that even if female brain is protected, that protection does not source back to any protective gene.
The importance of study was not only to show the difference in brain of boys and girls, but to stress the significance of conducting more researchers about autism in order to treat* patients properly.