Is mere exposure enough? the effects of bilingual environments on infant cognitive development

Bilinguals purportedly outperform monolinguals in nonverbal tasks of cognitive control (the ‘bilingual advantage’). The most common explanation is that managing two languages during language production constantly draws upon, and thus strengthens, domain general inhibitory mechanisms (Green, 1998). However, this theory cannot explain why a bilingual advantage has been found in preverbal infants (Kovacs & Mehler, 2009). An alternative explanation is needed. We propose that exposure to more varied, less predictable (language) environments drive infants to sample more by placing less weight on consolidating familiar information in order to orient sooner to (and explore) new stimuli. To confirm the bilingual advantage in infants and test our proposal, we administered four gaze-contingent eye-tracking tasks to 7- to 9-month-old infants who were being raised in either monolingual (n = 51) or bilingual (n = 51) homes. We could not replicate the finding by Kovacs and Mehler that bilingual bu...