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Contribution to Book
Investigating the empirical link between task-based interaction and acquisition: A meta-analysis
Synthesizing Research on Language Learning and Teaching (2006)
  • Casey Keck, Boise State University
  • Gina Iberri-Shea
  • Nicole Tracy-Ventura
  • Safary Wa-Mbaleka
Despite the seemingly rich context that task-based interaction provides for acquisition and the large amounts of research fueled by the Interaction Hypothesis (Long, 1996), oft-cited findings to date appear to be conflicting. While some studies (e.g., Ellis, Tanaka & Yamazaki, 1995; Mackey, 1999) demonstrate that task-based interaction can facilitate acquisition of specific linguistic features, others (e.g., Loschky, 1994) support no such relationship. This has prompted a variety of SLA researchers to question whether interaction can be empirically linked to acquisition. Over the past decade, however, and perhaps motivated by this criticism, the study of direct links between interaction and acquisition has gained momentum. The present meta-analysis was undertaken to synthesize the findings of all experimental, task-based interaction studies published between 1980 and 2003 which aimed to investigate the link between interaction and the acquisition of specific grammatical and lexical features. Results from 14 unique sample studies that satisfied stringent inclusion and exclusion criteria show that experimental groups substantially outperformed control and comparison groups in both grammar and lexis on immediate and delayed posttests. In addition, consistent with Loschky and Bley-Vroman’s (1993) proposal, tasks in which use of the target feature was essential yielded larger effects over time than tasks in which use of the target form was useful, but not required. Initial support was also found for Swain’s (1985, 2000) arguments that opportunities for pushed output play a crucial role in the acquisition process. Drawing upon these findings, and the synthesis of study design features, we propose specific recommendations for future interaction research.
  • second language acquisition,
  • meta-analysis
Publication Date
John Norris and Lourdes Ortega
John Benjamins
Citation Information
Casey Keck, Gina Iberri-Shea, Nicole Tracy-Ventura and Safary Wa-Mbaleka. "Investigating the empirical link between task-based interaction and acquisition: A meta-analysis" PhiladelphiaSynthesizing Research on Language Learning and Teaching (2006)
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