Unpacking the Concept of Complexity in Instructed SLA Research: Towards an Acquisitional Definition

Over the past few decades, the field of second language acquisition (SLA) has seen a remarkable increase of interest in the study of instructed second language acquisition (ISLA), which “investigates second language (L2) learning or acquisition that occurs as a result of teaching” (Loewen, 2014, p. 2). The importance of this subfield has particularly been emphasized for the sake of adult L2 learners, who, due to biological and cognitive constraints, have difficulty acquiring a target language (TL) solely based on naturalistic input (e.g., Han, 2004; Long, 1990). For this, ISLA research has suggested the utilization of focus on form (FonF), a pedagogical approach that attempts to engage learners’ metalinguistic attention in an otherwise solely meaning-based environment (Doughty & Williams, 1998; Long, 1991; Long & Robinson, 1998). According to Doughty and Williams (1998), FonF involves an array of pedagogical options, ranging from implicit techniques (e.g., input flood, input enhancement, and recasts) that attempt to attract leaners’ attention to form, to explicit techniques (e.g., processing instruction, consciousness-raising, and dictogloss) that attempt to direct their attention to form.