(NBC News) According to a new study from Vanderbilt University, some children with autism have trouble matching what they are seeing with what they are hearing.
Researchers compared over 30 high-functioning autistic children to those who are typically developing.
In one of the tests, the participants were asked to watch a video of a woman talking and to select whether her mouth moved at the same time as the sound or a different time.
Autistic children were slower to respond.
"They seem to synthesize this information over a longer period of time than the children who are typically developed," said Vanderbilt Researcher Mike Wallace.
But how that affects their ability to communicate or socialize is unknown and those studies are happening now.
This study doesn't tell us what does this really mean on a day to day basis, out in the field, in the home, in the school," Dr. Max Wiznitzer with UH Rainbow Babies and Children's Hospital said.
Vanderbilt researchers are looking at interventions for autistic lip sync issues with the hope of getting these children more in-sync with the world around them.
Researchers also say there's some evidence that autistic children outgrow this synchronization issue by their teens, but it could still have had an impact on their speech development.