The effects of increasing cognitive task complexity along [+/- planning Time] and [+/ – few Elements] on L2 oral production

Abstract

The study examines the impact of manipulating task complexity simultaneously along +/- planning time and +/- few elements on L2 production. Firstly, the concept of task complexity is presented, followed by a brief description of the Cognition Hypothesis and the Triadic Componential Framework. Finally, the specific literature related to planning time and the number of elements is reviewed. The first hypothesis states that reducing cognitive complexity along pre-task planning time will increase learners’ fluency and lexical complexity, whereas performing without time for planning will have negative effects on all dimensions of production. The second hypothesis predicts that increased number of elements will increase lexical complexity, structural complexity and accuracy, but it will cause disfluency. The combined effects of manipulating simultaneously two variables of task complexity as well as the role of different L1 backgrounds will be also analyzed. Using a repeated measures design, 14 upper-intermediate English level Spanish and Russian students were asked to perform four decision-making tasks manipulated along +/- planning time and +/- elements combinations. Measures included Unpruned Speech Rate A and Pruned Speech Rate B for fluency; Guiraud’s Index of Lexical Richness and the percentage of lexical words for lexical complexity; the number of clauses per AS-units for structural complexity; and the percentage of error-free AS-units and the percentage of error-free clauses for accuracy. The results of Friedman and Wilcoxon signed-rank tests showed that planning time positively affects lexical and structural complexity, but it does not display fluency or accuracy significantly. Increasing task complexity along the number of elements generates negative effects for fluency and structural complexity, a positive impact on lexical complexity and no significant effect on accuracy. The results, discussed in the light of Cognition Hypothesis and L2 production research, only partially confirm previous theories and findings (Skehan & Foster, 1997; Robinson, 2001, 2003, 2005; Gilabert, 2006; Michel, Kuiken & Vedder, 2007).