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.
Conclusion
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.