In several of my undergraduate classes, I noticed the same pattern. My notes would start out neat and organized, but as the lecture gained speed, my handwriting unraveled into rushed scribbles that barely qualified as text. The pace often outstripped my ability to process information, leaving me with fragments rather than understanding.
This reflects a challenge common in STEM education: the limits of working memory, the mental system that temporarily holds and processes information. When too much material is presented at once, students may struggle to engage meaningfully, leaving them with incomplete notes rather than lasting comprehension.
Cognitive science offers useful strategies for structuring material so students can manage this load more effectively. Well-designed video is especially suited to these strategies, since it can break down complexity, combine different modes of learning, and give students space to process ideas at their own pace.