This edited collection consists of a selection of conference papers that deal with the brain and SLA. The areas of focus are age and proficiency levels related to the critical period issue, ultimate attainment, and the regulation of two languages in a brain. The main chapters review the evidence in these areas and are each followed by a critical commentary.
There are seven main chapters: Birdsong provides an overview of age and second language (L2); Uylings discusses neuroanatomical changes; Green, Crinion, and Price investigate fMRI data, first language (L1)-L2 convergence, and individual differences; Rodriguez-Fornells, De Diego Balaguer, and Münte examine ERP evidence of the role of executive functioning in bilingual processing; Osterhout, McLaughlin, Pitänen, Frenck-Mestre, and Molinaro present ERP data and the effects of L2 instruction in a longitudinal study; Mueller considers more ERP data as well as artificial grammar processing in L1-L2; and, finally, Indefrey provides a meta-analysis of neuroimaging studies.
What does the volume give us that the original experimental reports do not? The principal virtue of the mix of review, data, and commentary on a loosely related theme is probably that the authors explain the thinking behind the various approaches to L1-L2 differences and provide thoughtful analyses of the difficulties more generally confronting a cognitive neuroscience of SLA. This is important because, as SLA increasingly deploys neuroscientific tools, researchers will have to consider carefully what answers can be obtained by seeking to ask a brain what it thinks.
For example, if it is hoped that finding the same gross neural activation for L1 and L2 is sufficient to claim definitively that the same processes are being used or that finding different activation for L1 and L2 provides a compelling demonstration that different processes are at stake, one would do well to note what several of the authors have to say about this, especially Osterhout et al. It will quickly become clear that such expectations are simplistic.
Hagoort raises the general concern about how to link cognitive and neural architectures. He reasons that if it is true that there is no transparent or lawful relation between the two, then “the attempt to connect brain and behavior is a useless endeavor” (p. 92). However, if this conclusion is indeed what follows from the premise, then readers might wonder what the point of the neurolinguistic enterprise could be, because the premise is certainly correct—our theory of language and our theory of brain do have not a single property in common, so there is no possible lawful relation between them that can be understood at this stage of theoretical development. Again, discussion of this sort is important.
Dijkstra and van Heuven point out that theories are needed to make sense of an otherwise “bewildering set of data” (p. 195). This is surely a truism, so it is surprising, given that the volume is about language-brain relations, that linguistic theory is not mentioned by a single contributor (other than Coopmans). In fact, not only is there no mention of linguistic theory, but there is also no clear indication in any chapter as to what theory of brain might be at issue. What is it, we might ask, that we are trying to integrate, if not some theory of language and some theory of brain?
The problem can be seen starkly in the final chapter by Schumann, who outlines a view of language that is not only unrecognizable but quite beyond comprehension. Apparently, language is a “cultural artifact” that has “a life of its own”; it is not “controlled directly by the brains of its speakers” but exists “between and among brains” (p. 314). Language, it seems, is not a brain property at all but a property of the environment. Unable to make any sense of this, I can only say that it is precisely the sort of thing you get when you have no theory of language.
Schumann is also impressed by the fact that Einstein's brain had certain enlarged areas, and he conjectures that “hypertrophies” in some brain regions might be responsible for “high proficiency in an L2” (p. 316). Pure phrenology. The sort of thing you get when you have no theory of brain.
This chapter is supposedly a summing up, but, as far as I can tell, it has nothing to do with the rest of the volume. The rest of the work sets out to consider the neural evidence regarding L2 critical periods and related issues, a task in which it succeeds rather well. It is probably fair to say, as the editors do, that it represents the state of the art.
