Why reviewing a video presentation twice at double speed achieves better retention than watching it once at normal speed.

Watching videos is now a major component of student learning and continuing professional development. Many participants take advantage of the fact that the videos are able to be sped up to reduce time spent reviewing them and I conducted a survey of my LinkedIn connections to see the approach they took . Does a change in speed have any impact on how much information we take in? A recent paper in Applied Cognitive Psychology explained the outcome of whether there is any difference and the answer is none. However, when you read further it is interesting to see that what most people think is going to be the best strategy is not the approach that will be most beneficial and there are specific approaches which we can adopt to improve our retention of information.

The research asked 231 students to review some YouTube videos at normal speed, 1.5x speed, 2x speed or 2.5x speed. They were told to watch the videos in full and to not take any notes. Once they had viewed the video they were given a comprehension test relating to the video content and these tests were repeated again a week later. The results showed that there was very little difference between normal, 1.5x and 2x speed and only 2.5x speed showed a drop in memory retention. The outcome therefore clearly shows that there is no real learning consequence of speeding up playback as long as the content can be accurately perceived and clearly understood.

However, the most interesting outcome for me from the research was that if the student watched a video at 2x speed and used the time saved to immediately watch it again at 2x speed their test results showed a significant improvement. Timing also plays a part and those students who watched the video twice at double speed and then repeated this double speed review again just before they took their test achieved the best test result outcomes. Research is ongoing as to the impact of leaving longer delays than a week between watching and on the differences in the complexity of the information reviewed.

Therefore even though the results of my survey showed that the majority preferred to watch videos at normal speed evidence would suggest that this is not the best way to use your time to maximise your comprehension of a subject and it might be time to resist your traditional conventional approach to learning and change the speed!.