Infants hear the language that is around them when they are born, and an infant’s mother’s speech creates unconscious neural patterns that remain even after an adoption into a family that speaks another language. These patterns, researchers have found, unconsciously influence the individual’s brain for a long time. Research into the lasting effects of “lost” languages was performed at the Montreal Neurological Institute and Hospital and McGill University. The study is the first to ever present evidence that parts of a child’s birth language remains in their brain, even if they never spoke a word of it themselves.
“The infant brain forms representations of language sounds, but we wanted to see whether the brain maintains these representations later in life even if the person is no longer exposed to the language,” Lara Pierce, first author on the paper, explained. The study was published in the science journal Proceedings of the National Academy of Sciences.
Functional MRI scans were performed on 48 girls between the ages of nine and 17-years-old. One group of the girls were raised only hearing and speaking French. A second group of girls were born hearing Chinese, but raised speaking French. This second group had no recollection of the Chinese language; that language was believed lost. A third group of girls grew up speaking fluent Chinese and French. While the fMRIs were performed, the girls all listened to the the same Chinese language sounds, according to Science Daily.
The brain activity of the second and third group that showed on the fMRI was shockingly similar.
“It astounded us that the brain activation pattern of the adopted Chinese who ‘lost’ or totally discontinued the language matched the one for those who continued speaking Chinese since birth. The neural representations supporting this pattern could only have been acquired during the first months of life,” Pierce said. “This pattern completely differed from the first group of unilingual French speakers.”
Pierce says that this research indicates that the first language of international adoptees is never actually lost. She says the birth language of the child continues to unconsciously influence brain processing, maybe for the rest of their lives.
One important idea that has surfaced from this research into the lost languages of international adoptees is that information acquired and experience that happen to infants during this “optimal period of development” continues to influence the brain throughout the child’s life, even though they do not remember it.
The study’s authors claim that this has significance to more than just language studies.
“This could counter arguments not only within the field of language acquisition, but across domains, that neural representations are overwritten or lost from the brain over time. The implications of this finding are far reaching, and open the door for questions relating both to the re-learning of an early acquired, but forgotten, language or skill, as well as the unconscious influence of early experiences on later developmental outcomes.”
[Photo credit: Montreal Neurological Institute, McGill University]