Could Eyes Be the Windows to Early Autism?

Autism symptoms in young children identified in infancy by eye contact tests

(RxWiki News) The earlier a developmental condition can be diagnosed, the sooner interventions can be provided. It would therefore be helpful to diagnose children with autism as early as possible.

A recent study has found one method that might help in beginning to diagnose children with autism as early as just a few months old.

The researchers found that children later diagnosed with autism spectrum disorders watched other people's eyes less and less between 2 and 6 months old.

After they were 1 year old, the children later identified as autistic watched objects much more often than children without autism.

The study was small but provides an area of future research in identifying very early symptoms of possible autism risk.

"Ask your pediatrician about developmental milestones."

The study was conducted by Warren Jones, PhD, and Ami Klin, PhD, both from the Marcus Autism Center at Children’s Healthcare of Atlanta and the Department of Pediatrics at Emory University School of Medicine.

The researchers wanted to determine how well autism could be predicted when children were babies based on differences in how they looked at things.

It has been long understood that not making eye contact is a common trait of autistic children, but it's not clear when this trait first shows up.

The researchers measured how much time 110 babies spent looking at other people at 10 different ages: 2, 3, 4, 5, 6, 9, 12, 15, 18, and 24 months.

Among these children, 59 were at high risk for developing autism because their sibling had the condition.

The other 51 children were at low risk for autism spectrum disorder because no first-degree, second-degree, or third-degree relative had been diagnosed with the condition.

At each eye viewing test, the children watched videos of natural-looking caregiving scenes while their eye contact was tracked.

The researchers calculated what percentage of the children's viewing time was spent looking at a person's eyes, mouth, body, and objects.

Then, when the children were 3 years old, they were assessed for whether they had autism or not.

Twelve of the high-risk children (10 males, one female) were diagnosed with autism spectrum disorder, and one child (male) from the low-risk group was.

The researchers then analyzed the data only for the boys since so few girls were diagnosed with autism.

The authors identified how the boys with autism differed from the boys without autism in the way their viewing changed as they grew up.

The children without autism looked mostly at people's eyes between 2 and 6 months and then increasingly at people's mouths as they reached 18 months old.

The typically developing children (without autism) always watched people's body parts more than objects, but they focused less and less overall on objects and non-face parts of the body as they got older.

Meanwhile, the children later diagnosed with autism gradually look at people's eyes less and less from 2 months on to 24 months old.

The autistic children did focus increasingly on the mouth as they got older, just as the typically developing children did.

However, the autistic children's focus on people's bodies and on objects decreased much more slowly as they approached 12 months old than it did in typically developing children.

Then, the autistic children began focusing on objects more in their second year. By 24 months old, the autistic children watched objects twice as much as non-autistic children did.

"In summary, the current results indicate that the development of infants later diagnosed with autism spectrum disorders differs already from that of their typical peers during the period from 2 to 6 months of age," the researchers wrote.

"These results, although still limited in sample size, document the derailment of skills that would otherwise guide typical socialization," they wrote.

This finding marks the earliest symptom of social difficulties that is currently known.

However, the researchers found that the trait is not present from birth. "Instead, eye looking appears to begin at normative levels prior to decline," the researchers wrote.

Glen Elliott, MD, PhD, a clinical professor at the Stanford University Department of Psychiatry and Behavioral Sciences, said this study offers a new direction for research.

“This publication is understandably creating a considerable stir in the autism world, suggesting that a specific finding at a very early age — far earlier than any other clinical indicator — might predict who is at risk for developing autism," Dr. Elliott said.

"It has implications both about the time of onset for brain changes that result in autism and possible interventions," he said. 

"Naturally, much more work is needed, and it is important to emphasize that this is much more sophisticated than just 'poor eye contact,'" Dr. Elliott noted. "Still, it opens important new avenues for researchers into possible underlying causes and perhaps treatment approaches.”

The study was published November 6 as a research letter in the journal Nature. The research was funded by the Simons Foundation and the National Institute of Mental Health.

Additional funding came from the Marcus Foundation, the Whitehead Foundation and the Georgia Research Alliance. No conflicts of interest were reported.

Review Date: 
December 1, 2013