Individuals with autism spectrum disorders (ASD) tend to stare at people’s mouths rather than their eyes.
Now, an NIH-funded study in 2-year-olds with the social deficit disorder suggests why they might find mouths so attractive: lip-sync-the exact match of lip motion and speech sound.
Such audiovisual synchrony preoccupied toddlers who have autism, while their unaffected peers focused on socially meaningful movements of the human body, such as gestures and facial expressions.
“Typically developing children pay special attention to human movement from very early in life, within days of being born. But in children with autism, even as old as two years, we saw no evidence of this,” explained Ami Klin, Ph.D., of the Yale Child Study Center, who led the research. “Toddlers with autism are missing rich social information imparted by these cues, and this is likely to adversely affect the course of their development.”
Klin, Warren Jones, Ph.D., and colleagues at Yale, report the findings of their study, funded in part by the National Institute of Health’s National Institute of Mental Health, online March 29, 2009 in the journal Nature.
For the first time, this study has pinpointed what grabs the attention of toddlers with ASDs,” said NIMH Director Thomas R. Insel, M.D. “In addition to potential uses in screening for early diagnosis, this line of research holds promise for development of new therapies based on redirecting visual attention in children with these disorders.”
Klin, Jones, and colleagues also recently reported that children with autism look more at peoples’ mouths than eyes as early as age 2. Since the mouth is the facial feature with most audiovisual synchrony ? lip motion with speech sound ? the researchers propose that their new findings offer a likely explanation for this phenomenon.
“Our results suggest that, in autism, genetic predispositions are exacerbated by atypical experience from a very early age, altering brain development,” said Klin. “Attention to biological motion is a fundamental mechanism of social engagement, and in the future, we need to understand how this process is derailed in autism, starting still earlier, in the first weeks and months of life.”
Source: National Institute of Mental Health, USA