Effects of the age of second language learning on the duration of first and second language sentences: The role of suppression

The primary aim of this study was to account for the finding that late bilinguals produce longer English sentences than early bilinguals. In Experiment 1, Italians who immigrated to Canada either between the age of 2–13 years (“early bilinguals”) or 15–28 years (“late bilinguals”) repeated matched English and Italian sentences following an aural model. The early bilinguals produced shorter English than Italian sentences, whereas the late bilinguals showed the opposite pattern. The same countervailing pattern was evident in Experiment 2, where bilinguals shortened sentences by 20% when instructed to repeat sentences as rapidly as possible. Subgroups of bilinguals who reported using Italian often M=46% Italian use) but not seldom (M=8%) were found to have produced significantly longer English sentences than native English (NE) speakers did. The results were interpreted to mean that the late bilinguals produced longer English sentences than the early bilinguals because they needed to expend more resources to suppress their Italian subsystem than the early bilinguals. The perceptual effect of sentence duration was evaluated in Experiment 3, where pairs of English sentences differing in duration were presented to NE-speaking listeners for foreign accent ratings. A 10% shortening caused sentences spoken by late bilinguals to sound less foreign accented but it caused sentences spoken by early bilinguals to sound more foreign accented.