Over the past two decades, researchers in the field of second language acquisition (SLA) have become increasingly interested in concepts traditionally associated with cognitive psychology. Recently in (SLA) research, much attention has been focused on cognitive mechanisms that underpin L-2 learners' performance in tasks with various constraints. The present study focuses on the phenomenon of 'attention' and presents empirical evidence of its role in shaping L-2 learners' performance in essay writing, unfocused and focused correction tasks. Fifteen female students in the department of English, Faculty of Education, UAEU participated in this study. They performed on three tasks; first essay writing; second, unfocused correction task, and third, focused correction task. The basis of the two correction tasks was the morphosyntactic errors that appeared in each subject's essay. Finally, each student was interviewed to explain her performance in the three tasks. The data analysis had a qualitative and a quantitative, interpretative part. Results were obtained; conclusions were made and suggestions for future research were proposed.