Last week an article appearing in The Sydney Morning Herald entitled Researcher points finger at PowerPoint generated quite a stir. The article highlighted findings by researchers from the University of New South Wales, including John Sweller who developed the Cognitive Load Theory back in the '80s. One of the findings mentioned in the article: it is more difficult to process information if it is coming at you both verbally and in written form at the same time. Since people can not read and listen well at the same time, the reporter suggested, then this may mean "the death of the PowerPoint presentation." The assumption being (apparently) that a presentation made with the aid of slideware such as PowerPoint or Keynote necessarily includes lines of text projected on a screen that mirror the spoken word of the presenter.
The article generated so much attention due in part to this quote by Professor Sweller:
"The use of the PowerPoint presentation has been a disaster. It should be ditched."
— John Sweller
Professor Sweller's comment makes a provocative headline and adds to the long list of professionals and researchers deriding the PowerPoint tool. I have added the professor's quote to my talks on the Presentation Zen approach. Two versions of the slide appear below.
Is PowerPoint a method?
I am assuming that what Professor Sweller means is that the way PowerPoint is used should be ditched, not the tool itself. Suggesting we abandon PowerPoint because it's often (usually?) misused and abused to produce awful presentation visuals is like saying we should dump the idea of 24-hour cable news because so much of it is vacuous rubbish. But whether we’re talking about bad TV or boring presentations, shouldn't we blame the content producers not the content medium? When people rail against PowerPoint they seem to be saying that PowerPoint is a method, and a flawed method at that. But is PowerPoint itself really a "method"? In a 2004 interview with Cliff Atkinson, Multimedia Learning author Richard Mayer said this:
"I do not think it makes sense to refer to PowerPoint as a method. Instead... PowerPoint is a medium that can be used effectively — that is, with effective design methods — or ineffectively, that is with ineffective design methods. We would not necessarily say that books are rarely a good method, because books can be designed using effective or ineffective methods."
— Richard Mayer
Cognitive load theory
I first read about the cognitive load theory as it relates to presentation in Richard Mayer’s Multimedia Learning. Sweller’s work is often cited in Multimedia Learning and many of his publications are also online. In this paper, for example, called Visualisation and Instructional Design (pdf), Sweller discusses several of the effects related to the cognitive load theory. For example, the modality effect shows that ”working memory can be increased by using dual rather than a single modality.” That is, it is more effective to target both the visual and auditory processors of working memory. Another effect in the cognitive load theory is called the redundancy effect (also outlined by Mayer in Multimedia Learning). The redundancy effect says that if one form of instruction (such as the spoken word) is intelligible and adequate then providing the same material in another form (such as lines of text on a screen that mimic the words being spoken) are redundant and can actually hurt understanding. This may seem counterintuitive and it certainly runs counter to many of the ways presentations are made in business or lesson taught in schools.
Below is another quote from Prof. Sweller from the same newspaper article. Here Sweller is surely referring to both the redundancy and modality effects:
"It is effective to speak to a diagram, because it presents information in a different form. But it is not effective to speak the same words that are written, because it is putting too much load on the mind and decreases your ability to understand what is being presented."
— John Sweller
In the scenario describe by Sweller above the diagram uses a visual modality and the speech uses an auditory modality which should result in greater working memory capacity and better understanding, depending, of course, on what is being presented.
Words should be presented as speech
The article in The Sydney Morning Herald put the ol’ bullet-filled PowerPoint slide back in the firing line. Good presentation techniques, and even classroom instruction methods, are as much art as science. Still, we can learn a lot from examining the findings from researchers such as Sweller and Mayer. Most of us know intuitively (or through experience) that presenting to an audience with text-filled slides does not work, but others — your boss perhaps — may need more convincing. This is where the research and evidence from specialists in psychology, education and other disciplines can be a great help. Research shows that visuals (animation) plus concise, simultaneous narration is better than just narration alone. When it comes to the issue of projected text on a screen and narration, Mayer draws this conclusion:
“Words should be presented as speech (i.e., narration) rather than text (i.e., on-screen text) or as speech and text.”
— Richard Mayer
What to do about PowerPoint?
So, is it finally time to ditch PowerPoint? Hardly, but it is long past time to ditch the use of the ubiquitous bulleted-list templates found in both PowerPoint and Keynote. And it’s long past time that we realized that putting the same information on a slide that is coming out of our mouths usually does not help — in fact usually hurts our message. Next time you plan a presentation, then, start by using a pencil and pad, a whiteboard, or a stick in the sand — anything except jumping headfirst into slideware on your computer with its templates, outlines, and content wizards that may point you down a path you wish not to go. And as you examine your work from previous talks remember this rule of thumb: if your presentation visuals taken in the aggregate (e.g., your “PowerPoint deck”) can be perfectly and completely understood without your narration, then it begs the question: why are you there?
• Book by John Sweller et al: Efficiency in Learning: Evidence-Based Guidelines to Manage Cognitive Load
• Bert Decker’s take on the newspaper article