The effects of cognitive task complexity on L2 oral production

This paper examines the impact of task complexity on L2 production. The study increases task complexity by progressively removing pre-task planning time and increasing the number of elements. The combined effects of manipulating these two variables of task complexity simultaneously are also analyzed. Using a repeated measures design, 42 intermediate learners of English perform four decision-making tasks under four conditions of cognitive complexity. Standardized measures of fluency, lexical complexity, syntactic complexity, and accuracy are used. Results show that fluency and lexical complexity are significantly affected by planning time. By increasing the number of elements, fluency is significantly reduced and lexical complexity increases, while syntactic complexity and accuracy remain unaffected. The combined effects of planning time and the number of elements also confirm the impact of task complexity on fluency and lexical complexity but not on syntactic complexity or overall accuracy. Results are discussed in relation to the Cognition Hypothesis (Robinson 2001, 2003, 2005, 2007; Robinson & Gilabert 2007).