Researchers examined how lecture video playback speed affects student learning by having undergraduates watch recorded lectures at normal speed (1x), faster speeds (1.5x, 2x, 2.5x), or by watching videos more than once at increased speed. Students completed comprehension tests immediately after viewing and again one week later. The study focused on whether faster playback harms understanding or long-term retention, a common concern among instructors using recorded lectures.
The key finding was that watching lecture videos at up to 2x speed did not significantly reduce comprehension, either immediately or after a delay, compared to watching at normal speed. Notably, students who watched a lecture twice at double speed often performed as well as—or better than—students who watched once at normal speed, particularly on delayed tests.
Interestingly, students’ intuitions about learning did not align with outcomes. While most students believed slower playback was better for learning, their test performance showed that faster viewing was equally effective. This suggests instructors may not need to discourage increased playback speed and could instead help students think strategically about when fast review is appropriate, such as when reviewing for an exam.
For teaching practice, the study suggests that recorded lectures can support efficient learning, freeing students’ time for deeper engagement activities such as practice problems or retrieval exercises. However, the authors caution that results may not fully generalize to highly complex or technical material, where slower pacing or pausing may still be necessary.
Read the full article here:
Murphy, D. H., Hoover, K. M., Agadzhanyan, K., Kuehn, J. C., & Castel, A. D. (2022). Learning in double time: The effect of lecture video speed on immediate and delayed comprehension. Applied Cognitive Psychology, 36(1), 69–82. https://doi.org/10.1002/acp.3899