A good starting point for understanding the emerging new identity of our field is to map the main theoretical currents and academic areas that are contributing to the ongoing restructuring process. Broadly speaking, psychological influences have affected SLA theory through two main channels: (1) learning lessons from the growing knowledge about the brain in cognitive psychology, psycholinguistics, neuropsychology, and cognitive neuroscience; and (2) drawing on the extensive research on first language (L1) acquisition, which has traditionally been studied by developmental psycholinguists. In this chapter, I will first inspect the various academic disciplines that address aspects of the linguistics–psychology interface, and then I will look at the various forms of language acquisition, from mother-tongue learning to instructed SLA.
Language, linguistics, and psychology: academic interfaces
The relationship between psychology and linguistics has been a curious one.
In our changing academic climate it will not come as a surprise to hear that language – the central topic of its ‘officially’ designated discipline, linguistics – is also a key area in the field of psychology. This is because language is more than a mere communication code or a cognitive linguistic system; it stands at the centre of human affairs, from the most prosaic to the most profound, and it is a basic ingredient of virtually every social situation. Accordingly, as Lightbown and Spada (2006: 1) summarize, the acquisition of language is ‘one of the most impressive and fascinating aspects of human development’. It is hardly surprising therefore that psychologists, whose mandate has been to try and understand the complexities of human behaviour and thinking, have spent a great deal of effort in the past analysing language-related phenomena – as of course have linguists. Yet, given this common interest, it is a curious fact of life that until very recently, scholars from the two fields had tended to work independently of each other, having no ongoing dialogue and without building on each others’ findings. In a paper devoted to the analysis of the evolving connections between psychology and linguistics, Segalowitz (2001) explains that although in the 1960s – following Chomsky’s work – the two fields had the potential of developing a close working association with each other, this potential never really materialized and ‘psychological research on language today is far less driven by recent advances in theoretical linguistics than it was then; similarly, a great deal of work in theoretical linguistics makes little reference to current developments in psychology’ (p. 3). Consequently, his overall conclusion was grim:
The sad truth is that many psychologists interested in language have not kept up with recent developments in linguistics … and it would also seem that many linguists are not aware of what is happening in psychology, especially in cognitive psychology and cognitive neuropsychology. (p. 4)
One fundamental reason for the divide between linguists and psychologists specializing in language has been that they have traditionally looked at the same phenomenon – language – from two different perspectives: broadly speaking, linguists have studied the language output of the speech/language production process (i.e. people’s oral and written discourse) without looking at how this output was generated. Accordingly, the main objective of linguistics has been to provide descriptive rules and patterns of the language system (e.g. ‘grammar’) without any concern for psycholinguistic validity, that is, whether the proposed system had any plausibility in terms of its neurological operation and development. Psychologists, on the other hand, have focused on the mental processes and structures whereby people understand, produce, remember, store, and acquire language, with little concern for the subtle linguistic patterns of the language code.
The breach between psychological and linguistic approaches has also been apparent within the field of applied linguistics. A decade ago Skehan (1998: 1), for example, stated that ‘Psycholinguistics, the study of the psychological processes underlying language learning and use, has been insufficiently influential on our profession as a foundation discipline, losing out in importance to linguistics and sociolinguistics’. While I believe that ten years later this claim still carries some truth because applied linguistics is still characterized by a dominant linguistic orientation, during the past decade we have witnessed a gradual but profound transformation in the relationship of the two disciplines. According to Segalowitz (2001), this change was the result of parallel developments in psychology and linguistics. In the former, advances in brain sciences and in modelling associative learning systems shed new light on the mental representations of linguistic processes, while in linguistics new approaches emerged that explicitly tried to link models of language to cognitive psychological processes. Applied linguists have been sensitive to this new spirit of cross-fertilization. An increasing number of studies drawing on psychological theories have been presented at applied linguistics conferences or in mainstream L2 journals: starting with the 2001 issue of the journal Annual Review of Applied Linguistics, a series of special issues have appeared in leading international journals, specifically focusing on the intersection of language and psychology (e.g. Applied Linguistics 2006: 27/4; Lingua 2008: 118/4; Bilingualism: Language and Cognition 2007: 10/1; Modern Language Journal 2008: 92/2; Studies in Second Language Acquisition 2003: 24/2, 2005: 27/2). Furthermore, this tendency has shown signs of acceleration recently – when I was collecting material for this book I was struck by the unexpected richness of the psychologically oriented SLA research of the past few years.
Interestingly, the gradual convergence of linguistics and psychology has been part of a broader paradigm shift in the traditional division of academic fields, with cognitive (neuro)science emerging as a new academic ‘top gun’. Baars (1997a: p. vii) describes this shift:
Ever since the nova scientia of Galileo and Copernicus began the revolutionary rise of modern physics, new sciences have been proclaimed with some regularity. Most of these announcements turn out to be false alarms. But today we actually find ourselves at one of those rare nodal points in the evolution of human understanding: For the first time … serious brain and psychological scientists are exploring conscious experience – often under obscure labels, but now with far better evidence and theory than ever before.
Let us have a look at the most important language-related fields with the ‘obscure labels’ that Baars was referring to above – ‘cognitive linguistics’, ‘psycholinguistics’, ‘neurolinguistics’, ‘cognitive science’, and ‘cognitive neuroscience’ – to see how they can inform applied linguists in the study of SLA.
Cognitive linguistics
Cognitive linguistics can be seen as a broad theoretical movement, subsuming different theories that share certain common features, the most important and most general of which being the commitment to work with constructs that have some psychological reality. (For SLA-specific overviews, see Achard and Niemeier 2004; Robinson and N. Ellis 2008b.) It is a relatively new area of linguistics, dating back to 1990, when the flagship journal of the approach, Cognitive Linguistics, was launched (N. Ellis and Robinson 2008).
Croft and Cruse (2004) list three major hypotheses that have guided the cognitive linguistic approach to language: (1) language is not an autonomous cognitive faculty; (2) grammar is conceptualization; and (3) knowledge of language emerges from language use. These principles are closely related to the usage-based theories of language acquisition discussed in Ch. 3 and, indeed, as Tomasello (2003) states, the new wave of usage/item/exemplar-based linguistic theories usually appear under the general banner of functional and/or cognitive linguistics.
The ‘cognitive’ label also reflects the general drive to make cognitive linguistic theories compatible with the main principles of cognition and, more specifically, with models in cognitive psychology, such as models of memory, perception, attention, and categorization. In the introduction to their recent comprehensive overview of the field, N. Ellis and Robinson (2008: 4) summarize this cognitive commitment:
The additional cognitive commitment of CL [cognitive linguistics] is to specify the interface of linguistic representation (grammatical factors), which can be used to