Some people are adamant you should never read your slides. Why? In part, because of research by Richard Mayer, author of Multi-Media Learning. But his research has been misinterpreted and misquoted, turning into the “Mayer Myth”.
In his famous study, he found students learned better when a speaker used picture slides than when the same speaker used text and picture slides. The implication: when the speech and text are identical, remove the text from your slides – called the redundancy principle.
Some people have interpreted this to mean never read your slides. But that’s not Mayer’s point. It only applies when you’re using pictures to illustrate what you’re saying. For instance, if you’re explaining how lightning forms, just show the process on slides and narrate it with your voice, rather than adding the exact same text to the slide.
In fact, Richard Mayer makes this explicit on page 159 of Multi-Media Learning:
“The redundancy effect should not be taken as justification for never presenting printed and spoken text together….Presenting words in spoken and printed form may be harmful in some situations – such as in the studies described in this chapter – but not in other situations – such as when the rate of presentation is slow or when no pictorial material is concurrently presented. For example, it might be useful to present summary slides (or to write key ideas on a chalkboard) in the course of a verbal presentation or lecture. This is a research question that warrants further study.”
I’m sure future research will show it harms learning to read paragraph-length text from your slides, or read from a dense forest of 12-point bullet points, or turn your back to the audience to read your slides.
But we may also learn that it improves learning to read 5-6 word bullet points, or a long sentence that is broken into lines of 5-6 words each, over using no text slides at all.
So let’s not misquote poor Dr. Mayer, the way we’ve misquoted poor Dr. Mehrabian. Dr. Mayer’s research only applies to slides with pictures that the speaker is describing.
In fact, he explicitly says just the opposite: you probably can use text to outline and summarize your talk.
So let’s stop spreading the “Mayer Myth”.
About the author: Bruce Gabrielle is author of Speaking PowerPoint: the new language of business, showing a 12-step method for creating clearer and more persuasive PowerPoint slides for boardroom presentations. Subscribe to this blog or join my LinkedIn group to get new posts sent to your inbox.