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San Diego Research Suggests Autism Develops During Pregnancy

Disorganized patches in the autistic brain suggest the disorder develops duri...

Photo by Eric Courchesne / UC San Diego

Above: Disorganized patches in the autistic brain suggest the disorder develops during pregnancy.

By pinpointing irregularly developed patches in young autistic brains, UC San Diego researchers have discovered new evidence suggesting autism begins in the womb.

In a study published by the New England Journal of Medicine, Eric Courchesne and his colleagues compared brain samples from autistic and typical children, all who died between the ages of 2 and 15.

The researchers specifically looked at layering in the cortex. These layers form during fetal development, and proper layering helps different brain regions and cell types communicate with each other. More than 90 percent of the autistic brains showed patches of disjointed layering.

"It's something that hasn't been seen before," Courchesne said. "The defect is such that it appears likely it occurred as early as the second or third trimester."

These brain samples have been difficult to obtain, making the study significant yet limited. Only 22 individuals were analyzed. However, the findings add to Courchesne's previous research finding an overabundance of cells in certain parts of the autistic brain.

Courchesne's latest work again points toward prenatal origins for autism. But the research is not conclusive, and Courchesne still isn't sure what exactly is driving this difference in fetal brain development. The results do poke even more holes in debunked theories claiming autism is caused by vaccines.

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