ABSTRACT
The academic discipline of instructed second language acquisition (ISLA), at its most basic, attempts to answer two questions: (1) is instruction benefi cial for second language (L2) learning, and (2) if so, how can the effectiveness of instruction be optimized? Because of this instructional perspective, ISLA has been used to refer to aspects of second language acquisition (SLA) theory and research that pertain directly to the L2 classroom. ISLA has focused, in particular, on the cognitive and psycholinguistic processes of L2 development which are arguably similar for all learners. In addition, the social aspects of L2 acquisition have been investigated, although perhaps to a lesser extent. Numerous research studies have investigated various facets of ISLA, and several books have provided a collection of studies (e.g., Housen & Pierrard, 2005) or a synthesized view of individual components of ISLA, such as grammar (e.g., Ellis, 1990). Even so, although Ortega (2013, p. 5) refers to ISLA as a ‘burgeoning subdomain’ of SLA, few works have attempted to go beyond individual research studies or specifi c linguistic areas to consider the broader scope of ISLA in an effort to bring together various issues and strands of research. This book endeavors to present a fuller examination of a range of topics and concerns related to ISLA. To that end, the current chapter considers the defi ning features and limits of ISLA. In addition, this chapter considers the foremost assumption of ISLA that L2 instruction matters and can be benefi cial for L2 learning. Although most L2 teachers and students may consider such an assumption to be self-evident (otherwise why spend so much time in the classroom?), they would surely agree that L2 instruction is not always successful and students do not always learn what is taught in the L2 classroom. Some SLA researchers (e.g., Krashen, 1982, 2003) would contend, in fact, that L2 learners acquire very little in the classroom that enables them to use the L2 for spontaneous communicative purposes; rather, these researchers propose that learners acquire a second language in a similar way to their fi rst language,
by being exposed to the language from its speakers and from other sources of input such as books, movies, and music. Even though views about the overall ineffectiveness of L2 instruction are in the minority in the fi eld of SLA, it is nevertheless important to ask, and investigate, if instruction really makes a difference for L2 acquisition.
