The present study examined whether early exposure in language immersion
would result in better preattentive discrimination of non-native speech sound
contrasts. Mismatch negativity (MMN) responses were measured from two groups of
Finnish children. The Monolingual group had no prior exposure to other
languages than the native one, while the Immersion group consisted of children
attending a French immersion program. The subjects were presented with two
vowel contrasts in the oddball paradigm: the first pair was phonemic in the
native language and the second was a within category pair in Finnish, but
phonological in French. The results revealed that the Monolingual group showed
a larger response to the native contrast in comparison with the non-native one,
whereas both contrasts elicited a similar response in the Immersion group.
These results suggest that early exposure to a new language enhances the
preattentive discrimination ability reflected in increased MMN amplitude.