A recent study has revealed that children with autism have a structural difference in their brain wiring compared to children without autism.
A team of researchers, including Advisor Charles Nelson (Harvard) found that children with autism have multiple redundant connections between neighbouring brain areas at the expense of long-distance links. Their findings were published in the journal BMC Medicine.
Neurons connecting to one another.
Image credit: Shutterstock
To analyze brain networks in this study, the team used electroencephalography (EEG), which involved placing multiple electrodes on children’s scalps to record their brain’s electrical activity. The researchers then used a process called graph theory to analyze the recordings. Graph theory is a mathematical representation of networks that allowed the team to look at the brain’s network performance as a whole, instead of studying local, individual connections.
The team analyzed EEG recordings from two groups of children with autism: 16 children with classic autism, and 14 children whose autism is part of a genetic syndrome known as tuberous sclerosis complex (TSC). They compared their EEGs with two control groups: 46 healthy neurotypical children and 29 children with TSC but not autism.
The researchers found that in both groups of children with autism, the disorder was characterized by a decreased long-range connectivity and an increased short-range connectivity in the brain. This finding may explain why individuals with autism can process local, simple information, like memorizing train stations, but not integrate information from remote areas that would help the patient understand, for example, that a raised voice and contorted face indicate that a person is angry.
Now that these altered connections have been identified, researchers can focus on understanding why the brain’s circuitry gets altered in autism and how this impacts behaviour.
This work was supported in part by the National Institutes of Health, the National Institute of Mental Health, the National Institute on Deafness and Other Communication Disorders, and the Department of Defense.