Ability to tell differences in sounds
Until babies reach their 8th month they are able to identify the deviation between sounds of all languages. It is still unclear to scientists why there is a transition when the babies’ brains begin to only focus on the available sounds that they hear, which seem to be due to their social interactions with people around them. This, the study says, may have an effect on their developmental transition.
The co-director of the Institute for Learning and Brain Sciences of the University of Washington as well as co-author of the study, Patricia Kuhl, explains that babies only start babbling when they reach their 7th month. They are likely to say their first words when they are one year of age. From their study they found that the motor areas of the babies’ brains are active even when they are only listening, which she says is a significant find since it means that the brain is already occupied in trying to talk back. She said that the brains of 7-month old babies are already working on how to form words.
Sensitivity to the native language
Ms. Kuhl, together with the members of the research group from the University of Washington, Toshiaki Imada, Jo-Fu Lotus Lin, Alexis Bosseler and Rey Ramirez believe that the motor planning the babies’ brains engage in already contributes to the transition when the babies will be able to recognize their native language. She said that the results of the study also show how important it is to talk to babies even if they are still unable to talk back. They are already practicing how to form and make words and hearing the people close to them talk in their native language is one sure way to aid them along the way. Parentese, which is speaking in slow and exaggerated speech, might also help infants to synthesize sounds and imitate them.
The research group used a brain scanning tool called magnetoencephalography, a world-pioneering method in measuring brain activation in infants using a noninvasive technique. The participants were made to listen to language syllables in Spanish and English as researchers recorded their brain activity in the auditory area of the brain. The 7-month and 11-month old infants responded to all sounds even if it was the first time they have heard them. It was different with the older infants, those that are 11 to 12 months old because their motor activation increased when they heard non-native sounds, compared to the brain activity when they listened to their native language. Researchers came to the conclusion that as infants grow older, their brains take more effort to predict the movements necessary to create speech which is non-native.