Babies remember key details about the first language they hear, a new study suggests. Researchers taught Korean to Dutch-speaking adults who had been adopted from South Korea as babies, and found that they were quicker to learn how to pronounce complex words. Interestingly, it made no difference whether the adoptees left South Korea as infants or toddlers.
“The knowledge retained by the early adoptees was as useful as the knowledge that the older adoptees had,” coauthors on the study Jiyoun Choi, of Hanyang University in Seoul, and Anne Cutler, of the Max Planck Institute for Psycholinguistics in the Netherlands, told Live Science. “And second, we showed that the knowledge was abstract in nature.”
Prior studies have indicated that infants have no concept of the sounds unique to specific languages until around six months of age when they first begin to recognize words. But this new research suggests that, even before then, infants are developing a sense of the sounds behind their native tongues.
For the study, Choi and colleagues recruited a small sample of 29 Dutch-speakers who had been adopted from South Korea and had no ability to speak Korean. Half of the participants were adopted between the ages of three and five months, and the other half was adopted at 17 months or older. After a short, intensive course of language study, the researchers found that all 29 participants had little difficulty learning how to pronounce Korean consonants that have no counterparts in Dutch. A sample of 29 Dutch speakers who had never lived in South Korea sat for the same course and invariably acquired this skill more slowly.
The results were based on a very small sample, so more studies will be necessary before researchers can definitively conclude that 6-month-olds carry vestiges of the first language they hear into adulthood. Until then, Choi says her study points to practical advice for parents.
”Useful language knowledge is laid down in the very early months of life,” she told The BBC. ”Try to talk to your babies as much as possible because they are absorbing and digesting what you are saying.”