Social eye contact in infants later diagnosed with autism appears to begin at typical levels but is already declining in the first months of life, according to a new study. Eye contact continues to decline in these babies up to 2 years of age. The findings – by researchers in Autism Speaks Baby Siblings Research Consortium– appear today in the journal Nature.
Reduced eye contact is a hallmark of autism in older children and adults. The new findings may show this important difference emerging in the first months of life. This suggests a possible new window of opportunity for early intervention, the researchers say. Eye contact is crucial for social interaction and learning.
If confirmed with further research, such an early decline in eye contact may represent one of the earliest signs of autism, they add.
The report’s co-authors are Warren Jones and Ami Klin, of the Marcus Autism Center, Children’s Healthcare Atlanta and Emory University. Dr. Klin is also a principle investigator in Autism Speaks Baby Siblings Research Consortium.
The consortium consists of 26 research groups studying babies with older siblings on the autism spectrum. These “baby sibs” are at high risk for autism because the disorder tends to run in families. Indeed, the consortium’s earlier research showed that these younger siblings have a 20-fold increased risk of autism.
“By studying high-risk infants, the researchers in Autism Speaks Baby Siblings Research Consortium are deepening our understanding of autism’s early development,” comments Alycia Halladay, Autism Speaks senior director for environmental and clinical sciences. “This includes important findings on earlier signs and symptoms, causes and developmental patterns. Ultimately, these discoveries will help us identify what can make an important difference in a baby’s development.”
Subtle differences detectible only with technology
In their study, Drs. Jones and Klin used eye-tracking technology to measure the way infants look at and respond to social cues in a video of a friendly caregiver. They studied 110 infants, 59 of whom were at high risk for autism because each had an older sibling on the spectrum. The other 51 had no known relatives with autism.
The researchers tested each infant 10 times between 2 and 24 months. Initial levels of eye contact for both groups were similar. But infants who did not develop autism increased their eye contact over time, while eye contact steadily declined among the 13 infants later diagnosed with autism. (Twelve of these were from the high-risk group.)
In addition, those infants whose levels of eye contact diminished most rapidly were the most disabled by symptoms of autism at age 3.
Parents shouldn’t worry if an infant doesn’t always meet their eyes, the researchers emphasize. The changes they documented with technology are not visible to the naked eye. Indeed, earlier studies without the eye-tracking technology failed to capture the pattern.
Editor’s note: Autism Speaks Baby Siblings Research consortium recently published a summary of ten years of research into the early signs and symptoms of autism – organized around three questions frequently asked by parents. Read it here.
Autism Speaks Vice President for Medical Research Paul Wang was interviewed about the study by North Carolina television station WBTV. Watch the story below. And read Dr. Wang's blog on what these findings mean for families here.