Werker – Korean study

I think the question of a critical period for language acquisition also needs to be addressed at different levels of language. So vocabulary we can probably continue to acquire throughout our lives. There’s no critical period for the acquisition of vocabulary. Syntax, or the grammar of language, becomes more difficult. Phrenology, the sound properties of language becomes more difficult. And there the question of exposure and training conditions I think becomes really important.  

There’s one recent study that I think is really interesting and makes us all pause when we think about the notion of critical periods. And this is a study that was done in France by Christophe Pallier and others, where they looked at French speakers whose initial language was Korean. They were Korean war orphans who were adopted into French-speaking homes in isolated little villages, up to the ages of eight or nine. And subsequently, at the time of adoption they spoke no French, they spoke only Korean. Subsequently they had virtually no exposure to Korean throughout the rest of their lives. And now as adults, middle-aged adults many of them, their ability to speak French is no different than any other French person. They can’t find any differences in their perceptual capabilities for French; they can’t find any differences that are really significant in brain-imaging studies of their response to French and conversely there’s nothing left of Korean that they can reveal at any level of analysis.  

And so this I think is a powerful example of how there is more flexibility after the age at which we thought there wasn’t and it’s in a circumstance where interference from the first language has been removed. So many of us now are reexamining our assumptions about critical periods. And when we see evidence of something that looks like a critical period in language acquisition, how much of it is based in something that’s unchangeable and how much of it is based in sort of an interaction between biological development and the types of learning and listening experiences that the child has had.