Subjects: R and D
When it comes to the early diagnosis of autism, scientists are on a roll.
Last month, a group at Yale showed that autistic children could be differentiated from age-matched controls by their responses to visual and auditory cues in cartoons.
Now, a group at UNC has demonstrated using MRI scans that a specific part of the brain known as the amygdala was roughly 13% larger in autistic children than it was in normally developing kids, even after adjusting for age, gender and IQ.
To reach this conclusion, Joseph Piven and colleagues scanned the noggins of 50 toddlers with autism and 33 age-matched controls that were developing normally.
“We believe that children with autism have normal-sized brains at birth but at some point, in the latter part of the first year of life, (the amygdala) begins to grow in kids with autism,” Piven told CNN.
The amygdala helps people process faces and emotions, a behavior known as joint attention. Piven’s group confirmed that toddlers with big amygdalas had joint attention problems.
“We would basically try to get the child to look one way, we’d turn and point to a clock and see whether or not the child would notice it,” Piven explained. “The 2-year-olds without autism would…see where you are looking and join you but the children with autism, with large amygdalas, would not.”
Autism experts say such findings are critical in developing new ways to diagnose autism and initiate treatment earlier in the course of the disease.
Autism affects about 1 in 150 children. It is the most rapidly growing serious developmental disability in the US. The average age for diagnosis of autism is 3.
The findings appear in the Archives of General Psychiatry.