Maturation: For better or for worse?

Abstract

Meisel has argued in favour of the Fundamental Difference Hypothesis (FDH), a version of the Critical Period Hypothesis, for L2 acquisition. Most particularly, he has proposed that maturational changes in domain-specific, language learning mechanisms are in evidence as young as four years of age. In a nutshell, the proposal is that for certain domains of morphosyntactic acquisition, if exposure to a language does not begin before 4;0, the developmental sequences will be different from (2)L1, and more like adult L2. Thus, even early child L2 (cL2) can be characterized as fundamentally different from (2)L1 because the configuration of internal learning mechanisms used to develop certain linguistic domains differs between these populations. The FDH, like all critical period hypotheses, casts maturation of the language making capacity (LMC to adopt the same terminology as Meisel) in a negative light. In other words, the system is not only changing, it is changing for the worse: what was once possible is no longer possible, such as mastery of a gender system or alleged error-free acquisition of gender. However, neuro-cognitive maturation need not be considered synonymous with a decline in the LMC in all respects. What I focus on in this commentary is the research evidence supporting a maturational perspective that points to how some domains of the system can change for the better. I would like to argue in agreement with Meisel that neuro-cognitive maturation could result in fundamental differences between cL2 and (2)L1 learners. But, at the same time, I would like to highlight reasons why “difference” should not be treated as a euphemism for “deficit”. Maturational proposals are, of course, not restricted to L2 acquisition, but have also been put forward for L1 acquisition (e.g. Rizzi 1993/1994, Wexler 1998, 2003). Given that in the first five years of life, infants/ children are undergoing extensive neuro-cognitive development, it seems only logical to consider that innate linguistic knowledge, together with domain-specific and domain-general learning mechanisms, might be un-