Some babies are at risk for autism because they have an older sibling that has the disorder, researchers said.
To find new ways to detect Autism Spectrum Disorder (ASD) earlier in life, researchers at the University of Miami are exploring the subtleties of babies' interactions with others and how they relate to the possibility and severity of future symptoms.
The study helps us to understand the connection between early joint attention before one year and later ASD symptoms.
Joint attention is an early form of communication that develops toward the end of the first year. It's the act of making eye contact with another person to share an experience.
Previous studies have shown that low levels of initiating joint attention are linked to later autism symptoms in high-risk siblings.
The current study shows that joint attention without a positive affective component (a smile) in the first year is particularly important to this relationship.
"The ability to coordinate attention with another person without a smile, without an emotional component, seems to be particularly important for high-risk siblings in the development of ASD symptoms," said Devon Gangi, student in the UM College of Arts and Sciences and first author of the study.
"The detection of markers associated with autism early in life, before a child can be diagnosed with autism, is important to help identify children at the greatest need for early interventions," said Gangi.
The findings show that early joint attention initiation without smiling - matter-of-fact looking at an examiner to communicate interest in a toy - was negatively associated with ASD symptoms.
According to the study, the less joint attention without smiling at 8 months in a high-risk sibling, the more likely they were to have elevated ASD symptoms by 30 months.
The study was published in the Journal of Autism and Developmental Disorders.