4 Brain Differences In Patients With Genetic Autism, Revealed By MRI Scans
Researchers used MRI scans to uncover clear and visible differences in the brain structure related to cognitive and behavioral impairments in individuals with genetic autism. These results suggest that brain imaging could play a role in better identifying patients who are in most critical need of special interventions.
MRI scans revealed that the brains of genetic autism patients had clear impairments in these areas when compared to the brains of individuals without the condition. This is the first major study of its kind to identify such abnormalities in the brains of autism patients, the authors wrote.
Read: Autism Spectrum Disorder May Not Develop Entirely In Human Brain
“Often studies like this focus on high-functioning individuals, but this was an 'all-comers' group,” said study author Elliott Sherrin a recent statement. “When you look at a broad range of people like this, from developmentally normal to more significantly challenged, you're better able to find these correlations."
While the exact cause of autism remains unknown, research has suggested that some cases are due to abnormalities in a specific spot on the 16th chromosome known as 1611.2, the statement reported. Both deletions or duplications in this area of the chromosome can lead to distinct autistic characteristics.
"People with deletions tend to have brain overgrowth, developmental delays and a higher risk of obesity," said study author Julia P. Owen in a statement. "Those with duplications are born with smaller brains and tend to have lower body weight and developmental delays."
To better understand how these deletions and duplications affected the brains of autism patients, the researchers performed MRI brain scans on 79 patients who had the genetic deletion associated with autism, and 79 individuals with the duplication. In addition, the team performed MRIs on 64 family member who were unaffected by any genetic abnormality, and 109 random control participants, also without genetic abnormalities.
All subjects also underwent a number of cognitive and behavior tests, and had their brain scans reviewed by specialists in neuro-radiology. These tests soon revealed a number of stark differences between the brains of individuals with the chromosomal abnormalities and those without. For example:
1. The corpus callosum, a fiber bundle that connects the left and right sides of the brain, was abnormally shaped and thicker in the deletion carriers, compared to controls.
2. This same area of the brain was thinner in the duplication carriers, compared to controls.
3. Deletion carriers had examples of brain overgrowth, such as an extension of the cerebellum, the bottom back part of the brain, toward the spinal cord.
4. Those who carried the chromosomal duplication showed examples of brain undergrowth, and many had decreased white matter volume and larger ventricles, the cavities in the brain filled with cerebrospinal fluid.
In addition, these structural differences were also linked to behavioral trends in patients. For example, individuals with brain features associated with deletions reported they had a harder time living their daily lives, and had poorer communication and social skills. On the other hand, individuals with brain characteristics of duplication were associated with decreased verbal IQ scores.
For now, these differences are just another branching point for researchers to further understand how autism affects our brain and behavior. However, one day these findings could be used as an intervention tool, identifying patients in most critical need of help and ensuring they get it before it’s too late.
Source: Owens JP, et al. Brain MR Imaging Findings and Associated Outcomes in Carriers of the Reciprocal Copy Number Variation at 16p11.2. Radiology . 2017
See Also:
Brain Images Indicate Biomarkers For Autism Spectrum Disorder
ASD People's Brains Are More Symmetrical, Changing How Information Flows