Cross Talk Between Native and Second Languages: Partial Activation of an Irrelevant Lexicon

Bilingualism provides a unique opportunity for exploring hypotheses about how the human brain encodes language. For example, the "input switch" theory states that bilinguals can deactivate one language module while using the other. A new measure of spoken language comprehension, headband-mounted eyetracking, allows a firm test of this theory. When given spoken instructions to pick up an object, in a monolingual session, late bilinguals looked briefly at a distractor object whose name in the irrelevant language was initially phonetically similar to the spoken word more often than they looked at a control distractor object. This result indicates some overlap between the two languages in bilinguals, and provides support for parallel, interactive accounts of spoken word recognition in general.