Washington: Eye contact with others declines in 2 to 6-month-old infants, who are later diagnosed with autism, a new study has suggested.
The study said that eye contact during early infancy may be a key to early identification of autism.
Thomas R. Insel, M.D., director of National Institute of Mental Health ( NIMH), said hat autism isn't usually diagnosed until after age 2, when delays in a child's social behaviour and language skills become apparent.
Typically developing children begin to focus on human faces within the first few hours of life, and they learn to pick up social cues by paying special attention to other people's eyes.
Children with autism, however, do not exhibit this sort of interest in eye-looking. In fact, a lack of eye contact is one of the diagnostic features of the disorder.
To find out how this deficit in eye-looking emerges in children with autism, Warren Jones, Ph.D., and Ami Klin , Ph.D., of the Marcus Autism Center, Children's Healthcare of Atlanta, and Emory University School of Medicine followed infants from birth to age 3.
The infants were divided into two groups, based on their risk for developing an autism spectrum disorder. Those in the high risk group had an older sibling already diagnosed with autism; those in the low risk group did not.
Jones and Klin used eye-tracking equipment to measure each child's eye movements as they watched video scenes of a caregiver. The researchers calculated the percentage of time each child fixated on the caregiver's eyes, mouth, and body, as well as the non-human spaces in the images. Children were tested at 10 different times between 2 and 24 months of age.
By age 3, some of the children-nearly all from the high risk group-had received a clinical diagnosis of an autism spectrum disorder. The researchers then reviewed the eye-tracking data to determine what factors differed between those children who received an autism diagnosis and those who did not.
The study has been published in the journal Nature.