The explicit/implicit knowledge distinction and working memory: Implications for second-language reading comprehension

Following an extensive overview of the subject, this study explores the relationships between secondlanguage (L2) explicit/implicit knowledge sources, embedded in the declarative/procedural memory systems, and L2 working memory (WM) capacity. It further examines the relationships between L2 reading comprehension and L2 WM capacity as well as those between L2 reading comprehension and L2 explicit/implicit knowledge sources. Participants were late adult learners of English as an L2, with a relatively advanced level of English proficiency. They completed tests measuring their WM capacity, explicit knowledge, implicit knowledge, and L2 reading comprehension. Correlation analysis revealed significant relationships between L2 WM capacity and both explicit and implicit L2 knowledge. Exploratory factor analysis showed that explicit knowledge, WM capacity, and L2 reading comprehension loaded on a single factor whereas implicit L2 knowledge formed an independent factor with no relationship to L2 reading. The results suggest that L2 WM is able to manipulate and store both explicit and implicit L2 input through controlled and automatic processes. They also suggest that L2 explicit knowledge, connected with the control processes of the declarative system’s lexical/semantic features, and L2 WM, reflecting attentional resource capacity/allocation associated with control processes, play an important role in L2 reading comprehension. Although the distinction between explicit and implicit knowledge has long attracted the attention of applied linguists in terms of their contributions to language learning, the focus in second language research has been predominantly on linguistic development in general, with comparisons made between first-language (L1) and second-language (L2) acquisition. Examples can be found in a special issue of Studies in Second Language Acquisition (Hulstijn, 2005), which offers several articles dealing with conceptual and empirical issues concerning the role of explicit and implicit knowledge in the differential attainment of L1 and L2 proficiency viewed as “grammar.” In this context, what has been neglected is a © Cambridge University Press 2012 0142-7164/12 $15.00 Applied Psycholinguistics 2 Erçetin & Alptekin: Explicit/implicit knowledge, WM, and L2 reading focus on the distinct functions of explicit and implicit knowledge in the acquisition of specific language skills, that is, how explicit and implicit knowledge sources and the corresponding explicit and implicit processes of learning play a role in the acquisition of a language skill in the L2. Similarly, the limited research into the role of working memory (WM) in L2 skill acquisition has largely ignored the delineation of the specific interactions between WM and the multiple memory systems underlying long-term memory (LTM; Geva & Ryan, 1993; Harrington & Sawyer, 1992; Leeser, 2007; Miyake & Friedman, 1998; Walter, 2004). If, as indicated by N. C. Ellis (2005), explicit and implicit processes are dynamically involved in “every cognitive task and in every learning episode” (p. 340) and if WM (at least in its capacity as the “central executive”) is responsible for scheduling cognitive processing (Baddeley, 1986), then the interactions between WM operations and the declarative and procedural dimensions of LTM that sustain these operations are crucial for a thorough understanding of skill acquisition in the L2. Hence, descriptions of ways in which declarative and procedural dimensions of LTM underpin WM processes in the L2 remain inadequate, which in turn renders explanations concerning the role of WM in L2 skill acquisition unsatisfactory or, at best, incomplete. THE EXPLICIT/IMPLICIT DISTINCTION IN L2 KNOWLEDGE AND