How Your Audience's Brain Works
Your brain has a tendency to tune out after 10 minutes, ignore "boring" subjects, and require a lot of pictures to retain information. Those are three of the discoveries detailed in John Medina's new book, Brain Rules. I recently spoke to Medina, a developmental molecular biologist and teacher at the University of Washington School of Medicine to get a sense of how business leaders can apply his findings when making presentations to audiences large and small.
1. The brain tunes out after 10 minutes. Your audience might be with you at "Hello," but in most cases, listeners stop paying attention within 10 minutes. Since Medina began teaching in 1993, he has continually asked his students: "Given a class of medium interest, not too boring and not too exciting, when do you start glancing at the clock, wondering when the class will be over?" The answer is always 10 minutes. According to Medina, peer-reviewed studies confirm his observation. "Before the first quarter-hour is over in a typical presentation, people usually have checked out," says Medina.
The 10-minute rule is an important finding for anyone who delivers information to any sort of audience. If you want to hold people's attention, I recommend you introduce some sort of engaging device at or shortly before each 10-minute increment of your presentation. This device doesn't have to be complicated. A simple story will suffice, as will a review of the past 10 minutes. In my presentations, I often tell a relevant story, or better yet, show a video clip that is relevant to the previous discussion. If you're presenting via Webinar software (BusinessWeek, 4/18/08), you can use a tool to push a poll or a question to your audience. Again, be sure to plan these exercises at 10-minute intervals.
2. The brain doesn't pay attention to "boring" subjects. Your audience craves the meaning behind your ideas before learning about the details. According to Medina, "This comes directly from our evolutionary history. We didn't care about the number of vertical lines in the teeth of the saber-toothed tiger. We cared about whether it was going to clamp down on our thigh. We were more interested in the meaning of the mouth than the details."
Consider Medina's example to demonstrate how a presenter might offer meaning before detail: "Let's assume the presentation is a description of how water-treatment plants function. The first thing you might do is hold up a glass of water, look at it, and say to the audience, 'I'm going to drink this water in absolute safety. Three months ago, I would not have drunk this glass of water. Why? It would have killed me because it was impure.'" Once you deliver the meaning, you can launch into the details of how your technology works because the audience has been given a reason to care about the details.
3. The brain craves pictures. Medina agrees with advice in my previous columns: Conventional, text-heavy PowerPoint decks should be thrown out and replaced with image-rich slides. According to Medina, the brain doesn't see letters. It sees only pictures. That means your brain sees even a tiny letter as a picture and can choke on text. The more visual the input, the more likely it is to be recalled. Scientists call this the pictorial superiority effect. "Text and oral presentations are not just less efficient than pictures for retaining certain types of information; they are way less efficient. If information is presented orally, people remember about 10%, tested 72 hours after exposure. That figures goes up to 65% if you add a picture," Medina explains. In other words, throw out your text-heavy PowerPoint and replace the slides with a picture and four words at most.
Whether you incorporate these ideas into your next presentation is up to you. But consider Medina's advice: "This is not my opinion. This is the way the brain works. You can either ignore it or accept, but you can't change it."