a1 Stockholm University
Research has consistently shown there is a negative correlation between age of onset (AO) of acquisition and ultimate attainment (UA) of either pronunciation or grammar in a second language (L2). A few studies have indeed reported nativelike behavior in some postpuberty learners with respect to either phonetics/phonology or morphosyntax, a result that has sometimes been taken as evidence against the critical period hypothesis (CPH). However, in the few studies that have employed a wide range of linguistic tests and tasks, adult learners have not exhibited nativelike L2 proficiency across the board of measures, which, according to some, suggests that the hypothesis still holds. The present study investigated the relationship between AO and UA and the incidence of nativelikeness when measures of phonetic and grammatical intuition are combined. An additional aim was to investigate whether children and adults develop the L2 through fundamentally different brain mechanisms—namely, whether children acquire the language (more) implicitly as an interdependent whole, whereas adults learn it (more) explicitly as independent parts of a whole.
This study is part of the research program High-Level Second Language Use, funded by the Bank of Sweden Tercentenary Foundation (grant no. M2005-0459). The author wishes to thank all the 770-something persons who initially volunteered, and in particular the 220 who were eventually selected as participants for the study. Thanks also go to research assistants Linda Martins and Heléne Norstedt for doing an impeccable job with the data collection, and Heléne also with the VOT analyses. I’m deeply grateful to my colleagues Professor Kenneth Hyltenstam and Associate Professor Emanuel Bylund for their feedback on an earlier draft of the manuscript, and also to Lamont Antieau, who checked and corrected my English writing in no time at all.