The Effects Of Cognitive Task Complexity On Chinese EFL Learners' Writing Performance

For the last two decades,the research based on task-based approach has received growing attention in the field of second language acquisition.Among the research,much has been discussed about the effects of cognitive task complexity on learners'language performance.However,relatively few studies have focused on the influence of cognitive task complexity on L2 learners' writing performance.Besides,most of the previous studies only employed general measures of language performance and it was considered too general to detect the subtler differences in task performance.To address the problems mentioned above,the study is designed to investigate how cognitive task complexity differently affects the qualities of Chinese English major leaners'argumentative writing performance by employing both global measures of complexity,accuracy and fluency,and task-specific measures.Specifically,it attempts to find out the effects of cognitive task complexity on Chinese English major learners' writing performance with respect to accuracy,fluency,lexical and syntactic complexity and cohesive characteristics.A total of 30 sophomores majored in English participated the research and they were required to finish two argumentative writing tasks of different task complexity.The cognitive task complexity was manipulated along both the resource-directing and resource-dispersing dimensions based on Robinson's Cognition Hypothesis.Sixty argumentative essays were analyzed on six global measures and two task-specific measures.In terms of the global measures,the results indicated that increasing cognitive task complexity exerted negative effect on the accuracy of the Chinese English major learners' writing performance,positive effect on the fluency of the Chinese English major learners' writing performance,positive effect on the lexical complexity,but negative effect on the syntactic complexity of the Chinese English major learners'writing performance.As for the task-specific measures,it was indicated that increasing cognitive task complexity exerted positive effect on the overall frequency of the conjunctions of the Chinese English major learners' writing performance,but no significant effect was found with regard to the cohesion indices of their writing performance.It was indicated that the findings were more in line with the predictions made in the Limited Attentional Capacity Model.Besides,qualitative approach was also adopted to further analyze how the effects of cognitive task complexity was reflected in the writing samples and it was found that in the more complex task,participants tended to commit more verb-centered and word-level errors,to employ longer T-units,to use less subordinate sentences,and to use more varied and complex vocabulary.The findings of the present study may not only provide more empirical evidence for the hypotheses of cognitive task complexity in the field of second language writing,but also offer a new insight for future research to measure the language performance more specifically.Pedagogically,this research could assist language teachers and syllabus designers in offering them a criterion for grading and sequencing pedagogical tasks.