Study Finds New Signs of Autism During the First Few Months of Life
Autism is a developmental disorder that affects one's ability to develop social and communication skills normally. Toddlers are usually diagnosed with this disorder around the age of three. Since autism is often treated with behavioral therapy, researchers have been studying ways of detecting autism even earlier so that treatment can start as soon as possible. In a new study, scientists from the Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, discovered new markers for autism in infants between two- and six-months-old.
For this study, the research team followed two groups of infants separated based on their risk of autism. Infants who had an older autistic sibling were placed in the high-risk group, whereas infants in the low-risk group did not have any first, second or third degree relatives with autism. The team started following the infants when they were born until they turned three-years-old. The team used eye-tracking technology to monitor how the infants looked at and responded to certain social cutes.
"By following these babies from birth, and intensively within the first six months, we were able to collect large amounts of data long before overt symptoms [of autism] are typically seen," said Warren Jones, Ph.D., the lead author on the study.
By the age of three, the researchers enlisted the help of clinicians to diagnose or confirm the diagnoses of any of the toddlers with autism. The researchers found that infants who were diagnosed with autism later on were already slowly avoiding eye contact with other people from two-months-old and onward.
"We found a steady decline in attention to other people's eyes, from 2 until 24 months, in infants later diagnosed with autism," said co-investigator Ami Klin, Ph.D., director of Marcus Autism Center. "First, these results reveal that there are measurable and identifiable differences present already before 6 months. And second, we observed declining eye fixation over time, rather than an outright absence. Both these factors have the potential to dramatically shift the possibilities for future strategies of early intervention."
The researchers remind parents that the study used advanced technology to monitor infants' eye contact and eye movement. Parents would not be able to determine their newborns' risk of autism using the naked eye. The researchers believe that this method of observing eye movement could be used for high-risk infants. By diagnosing autism at the earliest point, interventions could occur faster, which could lead to better treatments.
"The genetics of autism have proven to be quite complex. Many hundreds of genes are likely to be involved, with each one playing a role in just a small fraction of cases, and contributing to risk in different ways in different individuals," said Jones. "The current results reveal one way in which that genetic diversity may be converted into disability very early in life. Our next step will be to expand these studies with more children, and to combine our eye-tracking measures with measures of gene expression and brain growth."
The study was published in Nature.