Researchers have analyzed brain scans and eye movements as harbingers of autism. Now they’re listening to babies’ cries. Scientists at Brown University think it’s possible that infants’ early cries might provide a clue to whether they’re at risk of developing autism, based on a small study they conducted on about 40 babies. They compared the cries of one group, considered at risk of autism because they had older siblings with the disorder, to a second low-risk group. When the babies were six months old, they were videotaped in order to collect a vocal sampling. At some point during the 45-minute filming, the infants cried.
Researchers isolated the cries and conducted computerized acoustic analysis on the recordings to isolate different frequencies. They also separated out the cries based on whether they were related to pain — if a baby fell in the video, for example, then started wailing — and compared the two groups’ pain-related vocalizations.
The 21 at-risk babies had higher-pitched cries that were “low in voicing,” which translates into a rougher, less clear sound that could indicate their vocal cords are tenser than infants in the low-risk group. What’s more, the three babies with the highest-pitched cries went on to receive an autism diagnosis, according to the study published in Autism Research.
The findings, however, shouldn’t lead parents to start assessing their babies’ cries, says lead author Stephen Sheinkopf, a psychologist at the Brown Center for the Study of Children at Risk. “We definitely don’t want parents to be anxiously listening to their babies cry,” says Sheinkopf, who points out that the differences in cries were detected by sophisticated technology and not people. “It’s unclear if the human ear is sensitive enough to detect this.”
What is clear is that the findings are intriguing enough to warrant follow-up, particularly since it’s so difficult to find indicators of autism in very young children. In most cases, diagnoses aren’t made before age 2 or so since the classic symptoms of autism — social deficits, difficulty interacting and communicating with others — can be hard to spot before then.
Linking cries with risk of autism is not an association drawn from left field, however; cries, in general, have been correlated with brain development. Babies who are born premature or have suffered birth trauma tend to have higher-pitched cries, while those with Down syndrome often make weaker, lower-pitched sounds. Older children with autism often make atypical sounds — more sing-songy, for example— and researchers wondered whether it might be possible to observe unusual sounds in infants at risk of autism. “Cries are clues to what’s going on neurologically, but they hadn’t been looked at in relation to autism,” says Sheinkopf.
Finding clues in infancy could have a significant impact on children who are affected by autism. “Autism seems to be a disorder that starts subtle and magnifies with age,” says Sheinkopf. Studies consistently show that early intervention with behavioral therapies can help to lessen or even reverse some of the developmental symptoms. And diagnosing the disorder as early as possible could enable these strategies to begin even sooner.