10 counter-intuitive, researched tips on use of video in learning
When considering video what do key pieces of research say about impact on learning outcomes. As it turns out video may seem instinctively useful but that is not always the case. Our limitations in terms of working memory, episodic & semantic memory, attention and perceptual systems all play a role in limiting the effectiveness of video. Understand how the mind works and you can use video more effectively and cheaply. Here’s seven research-based facts that you should perhaps consider when using video in learning:
1. Media rich not always mind rich
Intuitively we may feel that rich, high quality, high production value video with animation, graphics, background sound, music and narration makes for great learning. But the evidence suggests otherwise. This approach can often result in ‘seductive but irrelevant distractions’. Meyer and Moreno have researched this area in detail and found that cognitive overload and dissonance can often occur when too much information is being presented. Controlling the load on working memory is an important consideration. Lesson: video is not always a good medium for learning. Lesson: Video can inhibit as well as enhance learning.
2. Attention maxes out at 6 mins
Philip Guo has tracked median engagement times versus video length, aggregated over several million EdX maths and science video sessions. He found that the average engagement time of any video maxes out markedly at 6 minutes, regardless of its length. An interesting side finding was that students who had enrolled for the certificate engaged more with the videos. Lesson: keep videos below 6 minutes.
3, No to 1 hour lectures (even chopped)
The edX researchers, confirmed by the MOOC factory in Lausanne, have found that, in addition to avoiding the dreaded 1 hour lectures, one should also avoid simply chopping up the existing 1 hour lecture into 6 minute chunkes. Take time to rework and rehearse the chunks as small videos in themselves, not the result of meat-chopper editing.
4. Stay personal, informal & enthusiastic
An interesting research finding from MOOCs, where huge amounts of video have been used by millions of learners is that learners don’t like over-produced, TV quality presentation. They much prefer more informal, personal and, above all, enthusiastic performances by their teachers. Hesitations, a chatty relaxed style even corrected errors. Lesson: More YouTube than TV.
5. Image quality NOT key
Most video cameras these days produce good pictures. Even then you really have to know about ISO, depth of field, framing and so on to get the best results. However, on the basic issue of picture quality, it doesn’t matter that musch when it comes to retention.
6. Audio quality IS key
Poor quality video quality is rarely the problem when it comes to learning and retention. Bad audio can, however, cripple both. . are not necessarily damaging in terms of learning and retention, poor quality audio, however, is bad news. Nass & Reeves showed that poor audio, hissy, distant or robotic can seriously affect retention.
7. Do not mix video & text
Video and accompanying text is a no-no. Never put the script up at the same time as the video. It overloads working memory and damages learning. Mayer (2001 suggests that both a visual and a narrative description increases the amount of time information about the process can be held and processed in working memory, leading to measurable, lower retention.
8. Worked examples
In research on 862 videos from four edX courses, for subjects that rely on symbolic, semantic reasoning, such as maths, physics and coding, worked examples (a la Khan Academy or Udacity) work far better.
9. Size matters
In an HCI course I took the talking head was postage size stamp size in the bottom right of the screen. Nass and Reeves showed that screen size does matter when it comes to reaction. As my BBC film editor used to say – it’s all in the eyes.
10. Alternate heads & images
With talking heads, go full screen and alternate with slides. Use talking heads for conceptual explanation and slides for diagrams, images and pictures that really do explain a point and don’t merely illustrate the point.
There’s lots more to be said about the use of video in learning. I’ve been using it for over 30 years and all of the above are confirmed by that vast and wonderful experiment – YouTube. There’s lots of different types of video and when it comes to learning, it is vital that the optimal technique is used. TV and film, in that sense, are not the most useful guides as, for learning, you often have to break their rules.