Richard Mayer and Ruth Clark are
among the foremost researchers in the empirical testing of media and media mix
hypotheses in online learning. Their
e-Learning and the Science of Instruction
(2003) covers seven
design principles; multimedia, contiguity, modality, redundancy, coherence,
personalisation, and practice opportunities. Clear explanations are given about
the risks of ignoring these principles - with support from worked examples and
case study challenges. It should be a compulsory text for online learning
mix is not mind rich
Their precise studies have
confirmed that our media mix (text, graphics, audio, animation, video) in online
learning is often flawed, resulting in cognitive overload and dissonance. Perhaps
their greatest contribution has been in identifying redundancy as a serious problem
in screen-based learning but they are known for research that produces clear
practical recommendations that do not pander to those who think that media rich
automatically means mind rich.
If you were asked to sum up
the psychology of learning in three words, it would be ‘less is more’, that’s
also Mayer and Clark’s mantra. In one study, Mayer, et al (1996) presented 600
pieces of scientific learning and found that briefer versions, which were
concise, coherent and co-ordinated, resulted in far more effective learning.
They are precise in their recommendations, ‘There
is a clear pattern in which the more words added to the core verbal
explanation, the more poorly the student does in producing the core explanative
idea units. These results are consistent with the idea that the additional
words overload verbal working memory, drawing limited attentional and
comprehension resources away from the core verbal explanation
.’ The lesson
with text is to cut it ‘til it bleeds! Bullet points, simple writing,
highlighted keywords and short paragraphs are all useful screen writing
They are critical of gratuitous
graphics which are added to simply fill slots on pages of text. This is not
uncommon in e-learning where designers simply take a noun within the text and
slam in an associated image. This does nothing, according to Mayer and Clark,
than add cognitive load and slow up learning.
Background music and
environmental sounds create unnecessary cognitive load and distract from,
rather than increase, learning. Indeed, music, over longer periods of time can be
incredibly annoying. Note that this also applies to sounds, such as beeps or
applause, that reinforce right and wrong answers. This may be appropriate in a
games, but not for most online learning. Ear candy is as bad as eye candy.
They argue that ‘text and simple relevant graphics
improve learning as they use separate cognitive channels. They are not
absolutist on these rules, as text within graphics can be useful when
explaining a process or in labeling.
of text and animation
‘Text and animation
’ which both use the visual channel, cause
cognitive dissonance and often confuse rather than achieve learning. Animation,
like video, should use audio narration, rather than accompanying text.
They claim that words in both
text and accompanying audio narration can hurt learning. This is interesting as
it is often assumed that one needs both to cover accessibility issues. In other
words, they argue for using ‘audio and
’ without screen text. According to Clark and Mayer (2003), ‘audio
or text on their own
’ are better than
‘text and audio together
’. This is
confirmed by another study by Kalyuga, Chandler and Sweller (1999) where the
group with audio scored 64% better than the group with both text and audio.
They claim that one or other is redundant and will overload the visual and
A review of studies around
this concept, known as the redundancy
, by Sweller et al (1998) cites a list of research studies that all
point to the damage done to learning when redundant material interferes with
the efficacy of the learning. For example; they illustrate a point about
leaving out extraneous or distracting graphics in media with an experiment,
conducted by Harp and Mayer (1997), in which students were given a text to read
on lightning strikes. Students who read the passage accompanied by elaborate
colour photos with additional captions - as opposed to the text with simple
graphics - showed 73% less retention of knowledge and 52% fewer solutions on a
Mayer (1989), Mayer Steinhoff
Bower (1995) and Moreno and Mayer (1999) in five separate studies compared
graphics with text close to the graphics, and graphics with text below the
graphics, at the foot of the screen. In all five studies, learners who used the
co-located text and graphics improved their problem solving by between 43-89%.
Similar results have been found by Chandler and Sweller (1991), Pass and Van
Merrienboer, (1994). Making the learner’s eye jump from one part of the screen
to another is disruptive and reduces the effectiveness of the learning.
E-learning has also introduced heavy doses of rollover text which is displaced
away from the item over which the cursor rolls so that the pop-up text appears
elsewhere on the screen at a distance from the item in question. The research
confirms that this is to be avoided in learning programmes.
Backed up by the work of Nass
and Reeves at Stanford (subject of my next post), they recommend a more
conversational style, using first and second person language. This is not to
say that it should be over-friendly or condescending. It should feel like a
dialogue, not a lecture. They also recommend the use of an on-screen coach or
agent. Note that they absolutely recommend self-paced user control, as well as
frequent practice and context setting through interactions.
Their research explains why
broadcast TV and web design companies often fail to produce good online
learning. They are drawn to techniques that entertain rather than educate,
often adding media that unintentionally degrades the learning experience. This
is why Nielsen and others were so critical of Flash, as it encouraged, the
unnecessary addition of animation. On the other hand it confirms the use of
short video lessons, with images and audio, as a form of instruction.
Clark and Mayer were among
the first to seriously research the use of media in e-learning and have come up
with empirically tested conclusions, often repeated by others, which suggest
that many common practices in e-learning design are, in fact, wrong. They
actually result in harming rather than helping the learning process. They call
for simpler, less gimmicky use of media. Animation and audio do NOT necessarily
lead to better learning and may, in fact, degrade the learning experience.
and Chopeta Lyons (2004).Graphics for Learning: Proven Guidelines for
Planning, Designing and Evaluating Visuals in Training Materials
Mayer R E and Clark R, E-learning
and the Science of Instruction
(see p61 for multiple references), Pfeiffer,
Mayer (2001). Multi-Media Learning
Cambridge University Press
(1999). Developing Technical Training: A Structured Approach for Developing
Classroom and Computer-based Instructional Materials
Mayer R E, Systematic
Thinking Fostered by Illustrations in Scientific Text
. Journal of
Educational Psychology, 81, 240-246.
Mayer R E, and Gallini J K. When
Is An Illustration Worth a Thousand Words?
Journal of Educational
Psychology, 88, 64-73. 1990
Mayer R E and
Anderson RB. Animations Need Narrations
. Journal of Educational
Psychology, 90, 312-320. 1991
Mayer R E and
Anderson RB. The Instructive Animation: Helping Students Build Connections
Between Words and Pictures
. Journal of Educational Psychology, 90, 312-320.