Toddler’s Attention to Mother’s Speech May Be a Diagnostic Marker for Autism

In a diagnostic study, researchers found that toddlers with ASD paid significantly less attention to baby talk, and those that paid the least attention also had lower social and language abilities.

People with infants or toddlers tend to speak to their young ones in a playful voice using high-pitched tones and simple words. This phenomenon is known as parentese, motherese, or infant-directed speech. It’s also referred to as baby talk.

Although most youngsters respond well to this speech pattern, studies have shown that many children with autism spectrum disorder (ASD) prefer computer-generated sounds over motherese. And this tendency is not typically observed in children without ASD.

These findings left scientists from the University of California San Diego School of Medicine questioning if levels of attention to motherese speech could be used to diagnose autism in toddlers.

To investigate this further, the scientists conducted a diagnostic study using 653 toddlers aged 12 to 20 months with and without ASD. Their research was published on February 8 in the journal JAMA Network Open.

The team had the youngsters watch two videos presented on one screen. One video was a woman speaking in motherese, and the other depicted a non-human scene, such as abstract shapes or a busy highway accompanied by electronic music.

The team used gaze-contingent eye tracking to determine the amount of attention the toddlers spent on a specific scene.

The team found that toddlers without ASD paid attention to motherese around 82% of the time. In contrast, autistic toddlers attended to motherese from 0 to 100% of the time, indicating a wide range of interest.

However, a subset of toddlers who paid attention to motherese less than 30% of the time could be accurately diagnosed with autism. Moreover, those who showed the lowest interest in the motherese videos also had weaker social and language abilities.

Yet, toddlers with ASD who spent the majority of the time paying attention to the motherese video had more social and language abilities. The scientists say this underscores the diversity across the autism spectrum.

"The fact that we can reliably identify children with autism using such a simple and rapid eye-tracking test is really remarkable," said corresponding author Karen Pierce, Ph.D., professor of neurosciences at UC San Diego School of Medicine and co-director of the UC San Diego Autism Center of Excellence in a news release.

Identifying autism at a young age is critical. According to the NIH, autistic children who are diagnosed early and receive interventions are more likely to experience significant progress and positive long-term effects than those who do not receive early diagnosis and interventions.

Although healthcare professionals can accurately diagnose some children before the age of two years, typically, this occurs much later. Still, there are behaviors that parents can look for to help identify the first signs of autism.

According to the study authors, "insight into which toddlers show unusually low levels of attention to motherese may be beneficial not only for early ASD diagnosis and prognosis but also as a possible therapeutic target."