Cognitive task complexity and second language writing performance

This paper reports on a study in which two models proposed to explain the influence of cognitive task complexity on linguistic performance in L2 are tested and compared. The two models are Robinson's Cognition Hypothesis (Robinson 2001a, 2001b) and Skehan and Foster's Limited Attentional Capacity Model (Skehan 1998, Skehan and Foster 2001). Sixty-two Dutch university students of Italian performed two writing tasks with prompts of differing cognitive complexity. Linguistic performance was operationalized in terms of syntactic complexity, lexical variation and accuracy. The study provides partial support for the Cognition Hypothesis, in so far as the written products of the cognitively more demandings task turned out to be more accurate, with significantly lower error ratios per T-unit than those of the cognitively less demanding task. In addition stronger effects of cognitive task complexity were found for high-proficiency learners than for low-proficiency learners. No effects could be observed on measures of syntactic complexity or lexical variation.