Theories of second-language acquisition

Theories of second-language acquisition are various theories and hypotheses in the field of second-language acquisition about how people learn a second language. Research in second-language acquisition is closely related to several disciplines including linguistics, sociolinguistics, psychology, neuroscience, and education, and consequently most theories of second-language acquisition can be identified as having roots in one of them. Each of these theories can be thought of as shedding light on one part of the language learning process; however, no one overarching theory of second-language acquisition has yet been widely accepted by researchers. Theories of second-language acquisition are various theories and hypotheses in the field of second-language acquisition about how people learn a second language. Research in second-language acquisition is closely related to several disciplines including linguistics, sociolinguistics, psychology, neuroscience, and education, and consequently most theories of second-language acquisition can be identified as having roots in one of them. Each of these theories can be thought of as shedding light on one part of the language learning process; however, no one overarching theory of second-language acquisition has yet been widely accepted by researchers. As second-language acquisition began as an interdisciplinary field, it is hard to pin down a precise starting date. However, there are two publications in particular that are seen as instrumental to the development of the modern study of SLA: (1) Corder's 1967 essay The Significance of Learners' Errors, and (2) Selinker's 1972 article Interlanguage. Corder's essay rejected a behaviorist account of SLA and suggested that learners made use of intrinsic internal linguistic processes; Selinker's article argued that second-language learners possess their own individual linguistic systems that are independent from both the first and second languages. In the 1970s the general trend in SLA was for research exploring the ideas of Corder and Selinker, and refuting behaviorist theories of language acquisition. Examples include research into error analysis, studies in transitional stages of second-language ability, and the 'morpheme studies' investigating the order in which learners acquired linguistic features. The 70s were dominated by naturalistic studies of people learning English as a second language. By the 1980s, the theories of Stephen Krashen had become the prominent paradigm in SLA. In his theories, often collectively known as the Input Hypothesis, Krashen suggested that language acquisition is driven solely by comprehensible input, language input that learners can understand. Krashen's model was influential in the field of SLA and also had a large influence on language teaching, but it left some important processes in SLA unexplained. Research in the 1980s was characterized by the attempt to fill in these gaps. Some approaches included White's descriptions of learner competence, and Pienemann's use of speech processing models and lexical functional grammar to explain learner output. This period also saw the beginning of approaches based in other disciplines, such as the psychological approach of connectionism. The 1990s saw a host of new theories introduced to the field, such as Michael Long's interaction hypothesis, Merrill Swain's output hypothesis, and Richard Schmidt's noticing hypothesis. However, the two main areas of research interest were linguistic theories of SLA based upon Noam Chomsky's universal grammar, and psychological approaches such as skill acquisition theory and connectionism. The latter category also saw the new theories of processability and input processing in this time period. The 1990s also saw the introduction of sociocultural theory, an approach to explain second-language acquisition in terms of the social environment of the learner. In the 2000s research was focused on much the same areas as in the 1990s, with research split into two main camps of linguistic and psychological approaches. VanPatten and Benati do not see this state of affairs as changing in the near future, pointing to the support both areas of research have in the wider fields of linguistics and psychology, respectively. For the second-language learner, the acquisition of meaning is arguably the most important task. Meaning it is the heart of a language, not the exotic sounds or elegant sentence structure. There are several types of meanings: lexical, grammatical, semantic, and pragmatic. All the different meanings contribute to the acquisition of meaning resulting in the integrated second language possession.