Infants’ eyes may signal autism

It seems that signs of autism may surface in infants aged as young as 2 months, which would be the earliest known indicator of social disability, according to a recent study.

Because diminished eye contact is a hallmark of autism, researchers from Atlanta, Georgia, studied the amount of time babies spend gazing at caregivers’ eyes. They found that infants who are later diagnosed with autism at age 3 years show a decline in eye fixation beginning at as young as 2 to 6 months of age. Children who demonstrate the steepest decline tend to develop the most severe cases of autism.

The investigators assessed 110 children aged from 2 months to almost 3 years while they watched videos of friendly women acting like playful caregivers. They used eye-tracking technology to determine when the babies looked at the women’s eyes, mouths, and bodies, as well as toys or other objects in the background.

They found that children who later developed autism began, at the tender age of 2 to 6 months, to spend less time focusing on the women’s eyes and more time focusing on other things. By the age of 2 years, those babies who later received a diagnosis of autism spent about half as much time focusing on eyes as the children who were not later diagnosed with an autism spectrum disorder. Those who didn’t develop autism spent increasingly more time staring at the women’s eyes until about 9 months of age, when the amount of time spent staring at eyes leveled off and remained fairly constant through the toddler years.

The researchers admit the study was small, but they say that the timing of the decline in eye staring is important. Their study shows that babies later diagnosed with autism are not born with a deficit in eye staring or the absence of such. They have normal levels of eye looking until a few months of age, which means an opportunity for early intervention exists.

Tracking the babies’ gazes cannot be done with the naked eye by parents or pediatricians. Special technology is required.

The study was funded by the National Institutes of Mental Health.

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