The infant's brain retains language that it hears at birth and recognizes it years later, even if the child no longer speaks that language.
A new study study reveals that an infant’s brain may remember a language, even if the child has no idea how to speak a word of it.
The finding comes from a new study performed by a team of researchers from McGill University’s Department of Psychology and Montreal’s Neurological Institute who are working to understand how the brain learns language.
As it turns out, the language that an infant hears starting at birth creates neural patterns that the unconscious brain retains years later, even if the child completely stops using the language. The study offers the first neural evidence that traces of so-called “lost” languages remain in the brain.
Because these lost languages commonly occur within the context of international adoptions—when a child is born where one language is spoken and then reared in another country with another language—the researchers recruited test subjects from the international adoption community in Montreal. They studied 48 girls between the ages of nine and 17 years old. One group was born and raised speaking only French. The second group was bilingual, speaking French and Chinese fluently. And the third was Chinese-speaking children who were adopted as infants and later became French speakers, but discontinued exposure to Chinese after the first few years of life. They had no conscious recollection of the Chinese language. “They were essentially monolingual French at this point,” explained Dr. Denise Klein, one of the researchers, in an interview with TIME. “But they had been exposed to the Chinese language during the first year or two of their life.”