Baby talk is more than an affectionate habit.
New research from the University of the Sunshine Coast suggests it plays an important role in helping infants learn the basic sounds of language.
The study, led by UniSC researcher Dr Varghese Peter, examined whether the exaggerated pitch and stretched speech sounds commonly used when adults speak to babies help infants distinguish between vowel sounds.
“Infant-directed speech, often called baby talk, refers to the distinct voice and cadence parents use when speaking to babies, such as raising pitch, exaggerating speech sounds and shortening utterances,” Dr Peter said.
While previous studies have shown that infants prefer listening to this style of speech, its impact on early language learning has been less clear.
To investigate, researchers measured brain responses in four-month-old and nine-month-old infants, as well as adults, as they listened to vowel sounds spoken using both infant-directed speech and typical adult-directed speech.
In adults and nine-month-old babies, the brain produced a clear change detection response when it noticed differences between vowels, regardless of how the speech was delivered.
Four-month-old babies, however, showed a different pattern. When they heard vowels spoken in adult-directed speech, their brains produced a less developed response.
When the same vowels were spoken using infant-directed speech, their brains showed a more advanced response, similar to that seen in older infants and adults.
Dr Peter said the findings suggest the exaggerated sounds in baby talk make it easier for infants to tell speech sounds apart, supporting early language learning from as young as four months of age, well before babies speak their first words.
