New Technique Shows how Autism Impacts the Social Brain

The areas in the human brain that are linked to social behaviors are both underdeveloped and insufficiently networked in youngsters with a highly functioning form of autism. The discovery was published in the journal Brain and Behavior.

The Study

The findings of the study show how the brains in kids with autism spectrum disorder may work differently than in youngsters without the disorder, says Kay Jann, a postdoctoral researcher in the UCLA Department of Neurology.

Autism spectrum disorder or ASD is a range of related conditions that cause individuals to suffer from social communication issues; they can also experience restricted interests and engage in repetitive behaviors, and their senses can be easily overwhelmed.

Normally, as a child’s brain develops, blood flow becomes reduced and synapses of neurons are “pruned.” In patients with autism spectrum disorder, this occurrence does not happen.

ASD is characterized by an enlargement in the brain, with an overabundance of neurons. This happens because the normal “pruning” that usually occurs in childhood brain development does not happen with ASD. To supply a higher number of functioning synapses, there is an influx of extra blood flow to the frontal portions of the brain, the areas which relate to cognition and socialization.

MRI Shows Increased Brain Activity

A team of scientific researchers from the University of California, Los Angeles (UCLA) used MRI imaging technology to track blood flow in the brain and then how it factored into connections within the structure.

This was the very first time that a medical resonance imaging machine was used for the study of autism spectrum disorder. The team used magnetically labeled blood water as a tracer to study blood flow. Researchers also used the technology to determine how good separate brain areas are functionally connected. Both of these techniques are non-invasive and didn’t involve radioactive tracers or injections.
The approach has already resulted in new insights and alternative approaches for treatment of such mental health disorders like schizophrenia.

Researchers questioned that autism spectrum disorder may be the result of a decreased connectivity with specific networks that make up the “social brain.”
Impaired Brain Connections in Children with ASD
Researchers studied 17 children with high-functioning autism spectrum disorder and 22 typically developing children and adolescents. The groups were paired according to age 7-17 years old, gender and IQ scores.

In children with autism spectrum disorder, there was a discernible pattern of increased blood flow in the frontal area of the brain. Also noted, was a decrease in the connectivity between the nodes in the front and back of the brain in those who had autism spectrum disorder. The resulting lack of connectivity could mean that information can’t flow like it needs to between different areas of the brain. This is a characteristic of ASD.

Conclusion:

The research team is now planning to continue to study the relationship between brain connectivity and metabolism in people with autism spectrum disorder and to further study other important brain networks. It is their hope to define the range of variation in the factors and how they relate to the general population.