Autistic Kids May Have More Cells in Some Brain Areas
Study Finding Could Someday Lead to New Ways to Identify Autism Early
Early Autism Diagnosis
"Earlier intervention leads to improvement all the way around in children with autism. So the need for early diagnosis is there and this will be one of the signatures that will help identify kids at a much earlier age," Courchesne says.
Nicholas Lange, ScD, who co-authored an editorial on the new report, agrees. He is an associate professor of biostatistics at the Harvard University Schools of Medicine and Public Health in Boston.
"These neurons can be measured in a brain scan and this may help give the clinician more brain-based information to help clarify a diagnosis of autism," he says.
Today, the diagnosis is based on symptoms and behaviors, not blood tests, brain scans, or other tangible indicators.
Lange also points out that the diagnosis would be based on the number of brain cells in the prefrontal cortex, not head size.
A big head does not necessarily mean a child has autism, he says. "Many other things that have nothing to do with autism lead to big heads, including genetics. Just 20% of people with autism have big heads."
The fact that these neurons develop before birth is also telling, Lange says. "There are more neurons generated during fetal development in this small sample and this points toward a more precise genetic [cause] of the disorder."
Robert Ring, PhD, urges caution in interpreting the new findings. He is vice president for Translational Research at Autism Speaks, an autism advocacy and science group.
"The small size does limit our ability to draw any real conclusions, but it does raise a lot of interesting questions that warrant further investigation," he says.
For example, do non-autistic children with large heads also have a greater number of neurons in these regions of their brains? The findings are "an intriguing snapshot and really begs for replication in a larger sample."
Y. Jane Tavyev Asher, MD, tells WebMD there is more to diagnosing autism than measuring head size. If a parent is concerned that their child may have autism, get him or her evaluated right away, she says. Asher is a pediatric neurologist at Cedars-Sinai Medical Center in Los Angeles, Calif.
"The hallmark of autism is language delay. So if there is early language delay, shoot first and ask questions later," Asher says. "It is better to have started a little speech therapy and find out it's not autism, than to go from person to person being evaluated before starting speech."