How native is near-native? The issue of ultimate attainment in adult second language acquisition

TLDR

Studies show a negative correlation between age of L2 acquisition and performance, supporting a critical period and maturational decline in access to Universal Grammar. The authors contend that previous tests of the critical period are insufficient because they rely on learners who may not have reached native‑like proficiency. They establish criteria for native‑like proficiency and compare near‑native, non‑native, and control speakers on two tasks probing Universal Grammar. Near‑native speakers performed indistinguishably from native speakers on both tasks, indicating that native‑like competence is attainable even for older learners.

Abstract

A number of studies have reported that there is a negative correlation between age of L2 acquisition and performance on a variety of measures of L2 ability, and that individuals who begin learning an L2 after approximately 15 years of age fail to attain native-like levels of competence. These results have been interpreted as support both for the hypothesis that there is a critical period for L2 acquisition and for the hypothesis that there is a maturational decline in access to Universal Grammar (UG). We argue that extant results are not an adequate test of the critical periods hypothesis because they are based on the performance of learners who have not necessarily achieved native-like proficiency in the L2. In this study, we develop criteria to establish whether an L2 speaker has achieved native-like proficiency. We compare the performance of three groups (near-native speakers of English, non-native speakers and controls) on two tasks designed to tap aspects of UG which have been claimed to be subject to critical period effects. We found no significant differences between our near-native group and native speakers on either of the tasks. We conclude that native-like competence in an L2 is achievable, even by older L2 learners.