Abstract
In the linguistically demanding landscape of Pakistani higher education, the mastery of English-medium functional discourse often imposes a prohibitive mental burden on students. Applying the theoretical framework of Sweller's Cognitive Load Theory (CLT), this study utilises a quantitative, cross-sectional approach (N=385) to evaluate the role of generative AI as a cognitive intermediary in academic and professional composition. The research investigates the impact of AI tools on the "functional written discourse" of undergraduate and postgraduate students, specifically focusing on the optimisation of cognitive resources. The findings reveal a transformative reduction across three primary cognitive dimensions. First, addressing the functional utility and linguistic mechanics of writing, participants reported the highest reduction in Extraneous Load (Mean=4.41), with over 90% of students agreeing that AI effectively manages complex gr