Volume 43, Issue 4

1. Preliminaries For several decades the topic of age effects on ultimate attainment has been high on the agenda of many second language acquisition researchers. A first major evaluation of research in this area was published by Long (1990), who summarized the findings of studies conducted since Penfield and Roberts (1959) and Lenneberg (1967) developed their versions of a critical period hypothesis for language acquisition. Long (1990: 280) argued that the combined findings of the studies conducted to date warranted the conclusion that The ability to attain native-like phonological abilities in an SL begins to decline by age 6 in many individuals and to be beyond anyone beginning later than age 12, no matter how motivated they might be or how much opportunity they might have. Native-like morphology and syntax only seem to be possible for those beginning before age 15. In line with most proponents of a critical period for SLA, Long (1990: 280) posited that the decline in abilities is due to incremental (and presumably irreversible) losses of neural plasticity due to brain maturation.

Research on age-related effects in L2 development often invokes the idea of a critical period – the postulation of which is customarily referred to as the Critical Period Hypothesis. This paper argues that to speak in terms of the Critical Period Hypothesis is misleading, since there is a vast amount of variation in the way in which the critical period for language acquisition is understood – affecting all the parameters deemed to be theoretically significant and indeed also relating to the ways in which the purported critical period is interpreted in terms of its implications for L2 instruction. The paper concludes that the very fact that there are such diverse and competing versions of the Critical Period Hypothesis of itself undermines its plausibility.

While almost all observers agree that young children, older children, and adults differ both in initial rate of acquisition and in the levels of ultimate attainment typically achieved, they continue to disagree over whether the observed patterns are a function of nurture or nature. Is it simply that older starters do not do as well because they are less motivated, receive poorer quality input, spend less time on task, or (paradoxically) are hindered by superior cognitive development, or is it that they cannot   ? In particular, well-respected scholars differ on the existence, scope, and timing of putative maturational constraints on the human capacity for learning second (including foreign) languages. Some recent research on age differences is considered, in particular, studies purporting to provide evidence against claims of maturational constraints on (Second) Language Acquisition (SLA) and/or putative critical periods for L2 phonology, morphology and syntax. It is argued that, in each case, one or more of nine limitations or design flaws means that the findings are, in fact, unproblematic for at least some of those claims.

This commentary addresses the use of nativelikeness and non-nativelikeness in research relating to the age factor in L2A. I suggest that, in the context of the Critical Period Hypothesis as it applies to L2A, the criteria of nativelikeness and non-nativelikeness may be subject to abuse. I also argue that the use of the monolingual native standard for falsification of the CPH is undermined by departures from monolingual nativelikeness that are artifacts of the nature of bilingualism. Finally, I discuss ways that evidence of (non-) nativelikeness can be put to constructive use in research that investigates the upper limits of L2A attainment.

In this paper we discuss recent neuroimaging evidence on three issues: (1) whether the same “language” areas are used to process a second language (L2) as the first language (L1) (2) the extent to which this depends on age of acquisition and (3) to the extent that the same areas of the brain are used, are they used in the same way? The results examined here are in general consistent with the hypothesis that the same areas of the brain are in general used for both languages, even for relatively low proficiency speakers. On the other hand, it appears that these areas are not necessarily employed as efficiently in L2, even for languages learned early in life. This may show up as a shift to the overuse of one part of the L1 processing system and an underuse of another.

In this study, we test the prediction, derived from the Critical Period Hypothesis, that a native level in L2 grammar cannot be attained by learners who start acquiring a second language after childhood. We selected 43 very advanced late learners of Dutch (native speakers of German, French and Turkish) and compared their performance on a grammar test with that of 44 native speakers of Dutch. The test consisted of an elicited imitation task and a sentence preference task. In these tasks, participants were tested on their knowledge of dummy subject constructions. These construction types are known to be very hard to acquire for L2-learners of Dutch and are hardly covered in Dutch grammars or L2 Dutch textbooks. The results show that it is possible to attain a native level of proficiency for learners who start acquiring an L2 after puberty, even for learners with a typologically distant L1.