Two separate studies published this month indicate that it may be possible to use brain imaging techniques to reliably detect autism in children as young as 6 months of age.
In the first study, published in the American Journal of Psychiatry, researchers from across North America working on the larger and ongoing Infant Brain Imaging Study used a type of MRI called diffusion tensor imaging to study 92 6-month-olds deemed high risk because their older siblings had been diagnosed with autism.
What they found is that the organization of white matter in the brain plays a key role. Specifically, they looked at fractional anisotropy (FA), which in this case measured white matter organization using the movement of water through tissue. They found that FA values were higher in 6-month-old infants who went on to develop autism, but then underwent a dramatic drop over the ensuing months and were ultimately lower than the values of those without autism when measured again at 2 years of age.
"Infancy is a time when the brain is being organized and connections are developing rapidly," Dr. Alan Evans, co-investigator out of McGill University in Montreal, said in a news release. "Our international research team was able to detect differences in the wiring by six months of age in those children who went on to develop autism."
Meanwhile, a larger study published in the journal BMC Medicine investigated patterns of electrical activity in the brains of almost 1,000 children between the ages of 2 and 12. Using electroencephalograms (EEGs) consisting of caps of 24 electrodes, researchers identified 33 patterns they say can reliably distinguish children who have autism from those who do not.
The majority of the 33 patterns revealed decreased brain activity -- particularly on the left side of the brain, which is responsible for communication -- but roughly a third of the patterns showed increased activity.
"They may be the brain's attempt to overcompensate for the regions that should be working together," Frank Duffy, a developmental neurophysiologist at Boston Children's Hospital and an associate professor at Harvard Medical School, told WebMD. "There's also a high association of autism with seizure disorders. An over-connected brain may be more prone to seizures than an under-connected brain."
Researchers from both studies say they hope their methods and findings will pave the way to the very early detection of autism, as early intervention could in turn help improve children's outcomes later in life.