Does intensive exposure to a language early in life leave everlasting traces in the brain? In a previous study, we tested participants of Korean origin who had been adopted by French families while children, and stopped using their native language for 15 to 20 years. Behavioral tests showed that they had become unable to recognize Korean sentences among other sentences from several languages, and that they could not identify common Korean words. Moreover, they had similar brain activation patterns as native French speakers, when they listened to Korean, French, Japanese or Polish sentences.
We will present data from follow-up experiments designed to assess their linguistics skills in Korean and French. First, we tested Korean adoptees in discrimination and identification experiments involving Korean consonants. Second, we evaluated their knowledge of French on two dimensions : phonotactics and grammatical gender. We found that their performance differed markedly from that of Korean speakers and was quite similar to that of native French listeners.