Infant’s response to mother’s ‘baby talk’ could help diagnose autism years earlier, study finds

New research has found a direct correlation between how a child visually tracks their mother’s eyes and the condition. Photo / Getty Images

How a toddler responds to baby talk could help diagnose autism years before symptoms begin, according to new research.

A study examined responses to parents’ use of playful, emotional, exaggerated tones, known as “motherese”, to capture a child’s attention.

Eye-tracking tests showed that children who did not respond had weaker social and language abilities.

Professor Karen Pierce, of California University in San Diego, co-author of the research, said: “We know the earlier we can introduce treatment, the more effective it is likely to be.

“But most children don’t get a formal diagnosis until around the age of three or four.

“There is a real need for easy and effective tools that can be used on young children. Eye-tracking is a great place to start.”

The study in JAMA Network Open offers hope of a screening programme.

In experiments, 653 toddlers aged one to two years old were exposed to two one-minute videos featuring a woman speaking motherese or abstract scenes. Their eyes controlled which one played.

Participants without ASD (autism spectrum disorder) showed consistently high interest in the woman speaking motherese, spending an average 80 per cent of the time watching it.

They largely ignored the second video which showed a busy highway, abstract shapes and numbers and had accompanying electronic music.

However, fixation levels of peers diagnosed with ASD spanned the full range of concentration levels, with some focusing 100 per cent on the random images.

A group who fixated on motherese less than 30 per cent of the time could be accurately identified as having ASD through this measurement alone.

These children also showed lower scores on subsequent tests of language and social skills.

Toddlers who had ASD but still spent a majority of the time attending to motherese displayed greater social and language abilities, highlighting the diversity within the ASD population.

The scientific community says it really needs more tools to help in the diagnosis of autism. Photo / 123rf

Whether less attention to motherese is the cause of reduced sociability or merely a symptom has yet to be determined. However, researchers found it appears to be a highly accurate biomarker for a subtype of the condition.

Prof Pierce said: “The fact we can reliably identify children with autism using such a simple and rapid eye-tracking test is really remarkable.

“In future we hope to use a child’s attention to motherese as a clue for which treatments they may most benefit from and as a tool for measuring how well those treatments work.”

ASD symptoms

Children with ASD have problems with communicating, social interaction and are prone to repetitive behaviours. But most cases are not confirmed until after the age of four, which means therapy is started later.

Studies have shown baby talk stimulates children’s attention and learning, helping them develop language skills and emotional understanding.

It is characterised by higher and wider pitch, slower speech rate and a sing-song pattern of intonation that differentiates it from the more monotone style used when adults speak normally.

Parents use normal language but make it simpler by repeating words and speaking slower.

They also exaggerate facial expressions, such as opening the mouth wider, raising eyebrows and smiling a lot.

Scientists claim talking to babies gives them advantages in life far beyond a larger vocabulary.

They say chatting to infants under the age of one helps them make friends, as well as making them brighter because they are better able to discover the world around them.

If autistic toddlers do not pay as much attention to this speech style, it might affect their social skills later in life.

The eye-tracking test could be beneficial for early ASD screening, diagnosis and prognosis, and help clinicians identify which treatments would be most useful for the child.

Autism is estimated to affect between 50,000 and 100,000 adults and children in New Zealand.