When the purpose of your speech or presentation is to inform, or even to educate, as opposed to simply entertain, it’s particularly important to package your material in a way the audience can easily take in, understand and remember. The same applies to books.
In a recent study, researchers at Sheffield Hallam University discovered that students who received academic information in the form of a comic book scored more highly in the memory test afterwards than did students who had received the same information in straight text form. This is in keeping with Allan Paivio’s 1971 dual-coding theory, which suggests the human mind retains information in two different ways, verbally and visually. If we receive the same message both verbally and visually, we have twice the chance of remembering it.
For public speakers, there are two lessons here:
Make sure every signal you’re sending is congruent. As far as your material is concerned, this means if you’re displaying a slide the message it conveys must accurately match what you’re saying. If your audience is seeing one thing and hearing another, this will confuse them and hinder their capacity to remember either one.
At the more subtle level, this means all the non-verbal cues you’re personally giving out must also back up what you’re saying. If you’re telling the audience a fact, the wrong intonation or a conspicuous lack of eye contact may result in them at least subconsciously questioning whether they believe you.
Bring your material to life. For me, another explanation for students learning better from comics than text books is that illustrations interpret the information and give it a living face. However dry the data you’ve been tasked with presenting, it’s your responsibility as the speaker to infuse it with interest. The right images can certainly help with this but mainly it’s about finding an emotional hook to get your audience to care about what you’re telling them.