A McGill University research team has discovered that 6-month-old infants appear to be much more interested in listening to other babies than they are in listening to adults, which offers insight into early language development. According to a recent announcement from McGill, the researchers believe that an attraction to infant speech sounds may help to kick start and support the crucial processes involved in learning how to talk. The study findings could also potentially offer new avenues to help infants with problems such as hearing impairment that hinder the development of their language skills.
As described in an article in the March 2015 edition of Developmental Science, the researchers discovered this preference on the part of young infants by doing a series of experiments where they alternated playing a repeating vowel sound made by an adult woman with one made by a baby. The sounds were created using a special synthesis tool. By measuring how long each sound held the infants’ attention, the researchers discovered that the babies had a clear preference for the sounds made by the infant.
On average, the infants listened to the infant vowel sounds almost forty-percent longer than the adult woman vowels, say the researchers. They determined that this was not a preference for a familiar sound because the babies who took part in the experiment were not yet babbling themselves, so the infant-like vowel sounds that they heard were not yet part of their everyday listening experience.
Some babies showed their interest in other ways. They reportedly met the adult vowel sounds with fairly neutral, passive faces. However, when they heard infant-like sounds, they smiled or moved their mouths as they listened, or did both. They seemed to recognize that this was a sound that they could try to make themselves, even though they probably had never heard anything like it before.
McGill University researchers have posted a video clip of an infant on YouTube that illustrates their findings.
The researchers propose that parents and caregivers may already know this phenomenon on an intuitive level. “Perhaps, when we use a high, infant-like voice pitch to speak to our babies, we are actually preparing them to perceive their own voice,” said senior study author Linda Polka, PhD, of McGill’s School of Communication Disorders.
Polka explained that, as adults, we use language to communicate, but when a young infant starts to make speech sounds, it often has more to do with exploring than with communicating. She pointed out that babies typically vocalize when they are alone, without any interaction or eye contact with others. “That’s because to learn how to speak babies need to spend lots of time moving their mouths and vocal cords to understand the kind of sounds they can make themselves,” she said. “They need, quite literally, to find their own voice.”
According to McGill University, this study brings researchers closer to an understanding of the complex interplay between speech perception and speech production in young infants.
Source: Developmental Science, McGill University