Guest post by Lisa Ibanez, PhD, a research scientist at the University of Washington Autism Center, and Daniel Messinger, PhD, professor of psychology at the University of Miami, and a member of the Autism Speaks Baby Siblings Research Consortium.
Over recent years, we’ve been studying the development of autism in high-risk baby siblings. These “baby sibs” are the younger brothers or sisters of children with autism spectrum disorders (ASD). From past research, we know that around one in five baby sibs will develop an ASD by age three. Another one in five will have some ASD symptoms or a similar issue such as language delay.
Like other researchers in the Autism Speaks Baby Siblings Research Consortium (BSRC), we’re looking at behaviors in the first year of life that may predict whether a baby will go on to develop an ASD and, if so, how severely he or she will be affected. In particular, we’ve focused on “referential communication.”
Referential communication refers to the use of gestures, eye contact and the like to convey information about events and objects of interest. Typically it develops before speech. Previous research has shown that many children with ASD show deficits in these skills. We wondered whether we could document the emergence of such difficulties in high-risk baby sibs between 8 and 18 months of age. We explored whether such patterns might predict the severity of future autism symptoms.
Compared to a group of low-risk infants, the high-risk sibs showed less initiation of joint attention activities as early as 8 months of age. For instance, they were less likely to look at or point to an object to share interest with another person. Similarly they lagged in responding to joint attention cues. The classic example would be failing to follow someone else’s point. As a group, these children also lagged in the development of gesturing to request something.
Importantly, these early behavioral differences predicted outcome. Specifically, high-risk siblings who showed low levels of initiating joint attention tended to have higher levels of autism symptoms in their third year of life. High-risk siblings who showed fewer gains in signaling requests between 8 and 18 months likewise tended to have higher levels of autism symptoms.
These findings suggest that, during the first year of life, difficulties with nonverbal communication can predict later symptom levels and autism diagnosis.
Along with other BSRC researchers, we are now working to confirm these findings. By studying more children, we hope to pin down how early these differences in nonverbal communication can predict later symptoms.
For the moment, it appears that early communicative behaviors such as showing and requesting objects are key markers of early autism symptom in high-risk siblings. By monitoring these behaviors, healthcare professionals may be better able to screen for autism risk during infancy.
What’s more, many early intervention programs aim to improve these behaviors in preschoolers and toddlers. Our findings suggest it may be important to adapt these interventions to meet the needs and abilities of infants as well.
We want to thank Autism Speaks and its community of families and donors for supporting this work.