It's estimated that autism, a developmental disorder that disrupts communication and social interaction, affects about 3.4 out of every 1,000 children between the ages of 3 and 10, according to the U.S. National Institute of Mental Health (NIMH). Parents are generally the first to notice early signs of autism. The NIMH says that some known early signs that may indicate an autism spectrum disorder in a child include:
* By age 1, doesn't babble, point or gesture.
* Doesn't speak a single word by 16 months.
* By age 2, hasn't combined two words.
* Seems to lose language skills.
* Interacts poorly socially.
* Doesn't respond to his or her name.
* Doesn't smile.
* Makes poor eye contact.
* Doesn't appear to know how to play with toys and may repeatedly line up toys or other objects.
For the new study, Klin and his colleagues, including Warren Jones, compared 15 children with autism to 36 typically developing children, and to another 15 children who were developmentally delayed but not autistic. All of the children were 2 years old.
The children were shown 10 videos of adults looking directly into the camera and mimicking caregiving and playing with the child. While the videos were running, the researchers used eye tracking to assess the child's visual fixation patterns.