Second language development can be viewed as a complex and dynamic process in which learners follow non-linear trajectories and develop their language over a period of time (Larsen-Freeman, 2006). Intrinsic to the view of Complex Dynamic Systems Theory (CDST), a system is composed of hierarchical, interdependent subcomponents (learner, learner…

From a complex dynamic systems (CDST) perspective, language is understood as a dynamic system comprised of subsystems that change and develop over time in response to learner-internal and -external factors (Verspoor et al., 2008). Accordingly, language development is seen as a process responsive to the dynamic interaction between the learner and…

Adopting Complex Dynamic Systems Theory (CDST) in Second Language Acquisition (SLA) is a testament to the revolutionary and evolutionary advancement in theory and empirical practice in the field. CDST is revolutionary for the fact that it warrants systems thinking of SLA phenomena that breaks the chain of dichotomous conceptualization on vital…

Third language (L3) lexical acquisition is still underexplored. In this article I overview theoretical and empirical evidence on L3 lexical acquisition and the role of cross-linguistic influence (CLI) in learning L3 words. I explain the mechanism of CLI as resulting from language co-activation in the multilingual learner's/user's mind.…

Does complexity make multilingualism special? Since there is no unequivocal notion of complexity on which researchers agree, several characteristics that have been considered crucial for complexity are brought to bear on multilingualism. While multilingualism is fairly complex in some senses, for instance, because it requires that many variables…

In Krashen's theory of second-language acquisition he claims that there is distinction between language acquisition and language learning, a distinction which other second-language acquisition researchers have called "perhaps the most important conceptualization" in the field and which has made possible the most productive models of SLA.…

In the late 1970s and early 1980s, Stephen Krashen developed Monitor Theory--a group of hypotheses explaining second language acquisition with implications for language teaching. As the L2 scholarly community began considering what requirements theories should meet, Monitor Theory was widely criticized and dismissed, along with its teaching…

With the increasing consensus that a single effect of bilingualism is unlikely, some scholars shift their focus to elements that may exert an influence on the bilingual brain. One such element that has been garnering attention lately concerns the role of L1-L2 typological distance. In this conceptual analysis, I make the case that the foundations…

In a recent article published in this journal, Moscati and Crain (M&C) showcase the explanatory power of a learnability constraint called the Semantic Subset Principle (SSP) (Crain et al. 1994). If correct, M&C's argument would represent a compelling demonstration of the operation of an innate, domain specific, learning principle. However,…

Hudson Kam (2018) examined whether learning of a particular aspect of language that adults are known to have difficulty with (grammatical gender) could be improved by manipulating the learning experience of adults so that it was more like that of infants. Specifically, based on likely differences between adult and child learners' experiences as…

Instructed second language acquisition (ISLA) research has recently attracted more focal attention due to the publications of three books and as the theme of the 2016 Second Language Research Forum (SLRF) conference that celebrated its 35th anniversary in the field of second language acquisition (SLA). Recent definitions (e.g. Loewen, 2015) have…

Language proficiency is multi-componential in nature and, according to many SLA researchers and L2 practitioners, is best captured by the concepts of complexity, accuracy, and fluency (CAF). Two of the three studies reported in this paper adopted the Cognition Hypothesis (Robinson, 2003) as the means to address the question of whether increasing…

This article enters the debate about the complex and dynamical nature of second language acquisition (SLA) by discussing and commenting on Pallotti's critique of Complex Dynamic Systems Theory (CDST). Pallotti's critique brings to the fore the argument that, due to its anti-reductionist stance, CDST research fails to observe three fundamental…

Multilingual research could offer a unique perspective on how the languages already acquired by a person affect the online processing of a new language. But it is currently difficult to assess this issue because theoretical accounts of multilingualism have focused on acquisition rather than processing and most empirical research to date has…

This article has two main goals. The first is to summarize and comment on the current state of affairs of generative approaches to SLA (GenSLA), 35 years into its history. This discussion brings the readership of SSLA up to date on the questions driving GenSLA agendas and clears up misconceptions about what GenSLA does and does not endeavor to…