The Brain Folds of Children with Autism are Different from those of Neurotypical Children, Per MRIs
We all know that Autism is a complex disorder; just how complex of a disorder is starting to emerge all thanks to growing research studies being published and an increased interest from different Universities across the world. One discovery published recently and backed up by two separate studies digs deep down to the core differences of the brain in people with Autism and the changes that occur in these individual’s brains as they age.
According to Science Alert, “Now we have more reason to believe that the structure of the brain's top layer might play a significant role in turning Autism into an incredibly complex disorder.” You see, a pair of unrelated studies that were analyzing neural scans taken of young children and adolescents have come to almost identical findings about the structural development of individuals with Autism’s growing brains; and, they found large-scale differences.
The studies where done by University of California Davis and San Diego State University. These two teams of researchers wanted to look at the “LGI of children diagnosed with ASD to map the extent of their pleating in different areas of their brains.”
To understand where these studies are going you must understand that “our cortex does a lot of the heavy lifting in our thinking and reacting, controlling everything from our reasoning to communication.” The grey matter of our brains ripple into “ridges and crevices called gyri and sulci.” Some people don’t know but, per Science Alert, we can “measure the development of these neural tissue folds as changes in the local gyrification index (LGI): a ratio comparing the area inside the sulci with the smooth outer surface.”
The team that was headed by San Diego State University used MRI scans from 128 individuals. All these individuals were aged 7 to 19. According to their study’s release, “one half of the group had an ASD diagnosis, which was further detailed through a series of tests.”
Per Oxford Academic, researchers discovered “significantly more folding in the left parietal and temporal and right frontal and temporal regions among those with ASD, as well as a slightly thicker cortex around the deep crevice known as the lateral sulcus.” Their study went on to detail that the LGI of the individuals diagnosed with Autism declined among older members in each group. It is indicated that “this drop was more pronounced in several areas in those with a diagnosis of Autism.” The study is quoted as saying that these findings “may indicate that a trace of this developmental abnormality could remain in a disorder-specific pattern of gyrification (the process of forming the characteristic folds of the cerebral cortex, the peak being the gyri and the trough being the sulci.)
The study out of the University of California Davis, also published in the Oxford Academic, seemingly backed up the findings of San Diego. In this “separate piece of recent research,” the brains of “105 boys aged between 3 and 5 and diagnosed with ASD were compared with 49 controls over a period of several years.” Doing so over a period of several years gave the team a better idea of how exactly the brains changed over time in each individual studied.
Their findings suggest young children with ASD seem to have a “remarkably smooth fusiform gyrus – the part of the brain that helps us recognize faces.” Interestingly enough, they also found that the LGI was “increased at age three in several regions in 17 of the boys who had both ASD and slightly enlarged brains.”
This study went on to detail that by the age of five the folding across “several regions had increased among children with ASD, unlike those who did not have a diagnosis.” These studies make it importantly clear that Autism is an immeasurably complex disorder. We’ve long known that Autism is shaped by an array of genetic changes and environmental influences. Now we know that it also causes physical and deeply complicated changes in the brain of those that have it.
Per Science Alert, it is more than just these changes though. Rachel Zamzow at Spectrum was told by lead investigator Christine Nordahl that they think it “might reflect a physical distinction in an ASD subtypes.”
"We, more and more, are convinced that they really represent a distinct subgroup not only in terms of their brain size but their pattern of brain differences," Nordahl is quoted as saying.
I’m sure over the next few years much more research giving us a better idea about Autism will be released. This is due to the fact that many major studies, dating back to years ago, should be publishing their reports. A great deal of research is currently focused on “identifying physical differences that might appear early enough to give caregivers and the community an opportunity to find resources that might benefit a developing brain with ASD.” Both groups of researchers mentioned in this article reportedly intend to “follow up their work by continuing to study how those folding structures are distinguished in adolescent brains as they grow into adults.”
These studies also point out the importance of brain scans in the research of Autism. Per Science Alert, MRIs like the ones used in both of these studies “not only help identify unique differences but they could help point the way to understand how all of our brains grow and evolve.” I look forward to following these studies as they progress through the aging of the subjects to see the differences that they find and the questions they may answer through their work.