["Journal of Computer Assisted Learning, Volume 42, Issue 4, August 2026. ", "\nABSTRACT\n\nBackground\nThe Cognitive Theory of Multimedia Learning (CTML) has established fruitful principles to guide learners' attention and reduce their cognitive load. Although these principles have been shown to improve learning outcomes, it remains useful to examine learners' cognitive processes during learning using eye‐tracking techniques.\n\n\nObjectives\nTo mitigate cognitive load by segmenting content and directing the learner's attention to visual elements synchronised with auditory narration, we cumulatively presented visual segments within a single PowerPoint slide. We referred to this format as a cumulative presentation.\n\n\nMethods\nForty Japanese university students participated. They first completed a pre‐test to assess their prior knowledge, and subsequently viewed a biology lesson slideshow accompanied by teacher narration. In the cumulative presentation condition, visual elements were incrementally revealed alongside the narration, whereas in the whole‐slide presentation condition, all elements were presented simultaneously prior to narration. Throughout the session, we tracked the participants' eye movements. Following the lesson, all participants completed a post‐test identical to the pre‐test.\n\n\nResults and Conclusions\nLearning outcomes were significantly higher in the cumulative presentation condition than in the whole‐slide presentation condition (Cohen's d = 0.49). Participants in the cumulative presentation condition fixated earlier on visual elements congruent with the teacher's lecture (d = 1.76) and for longer durations (Cohen's d = 1.15). These findings demonstrate the effectiveness of cumulative presentation in enhancing learning and visual attention, provide empirical support for the segmenting principle, and suggest practical implications for designing multimedia instructional materials.\n\n"]