Your audience will check out of your next PowerPoint presentation after about 10 minutes. I know your presentation is engaging, I know you’re a wonderful speaker, and I know that your slides look really cool, but neuroscientists now know that the human mind gets bored after 10 minutes or so.

The other day I wrote this column about one of Steve Jobs’s most persuasive presentations—the 2003 launch of the iTunes music store, a 10-minute performance where he convinced people to fork over 99 cents a song at a time when millions of people were downloading songs for free. Ten minutes is all he needed. A revolution can be launched in ten minutes. Why, then, do you really need 90 minutes to get your point across?

I began writing about the rule after a conversation with scientist John Medina at the University of Washington. Medina says peer-reviewed studies, as well as his own studies and observations, confirm that the human mind starts to get bored after ten minutes. “The brain seems to be making choices according to some stubborn timing pattern, undoubtedly influenced by culture and gene,” says Medina.

Let’s take a college class as an example. Medina asks every new group of students this question: “Given a class of medium interest—not too boring and not too exciting—when do you start glancing at your watch, wondering when the class will be over?” The answer, without fail, is 10 minutes.

The 10-minute rule has huge implications for your next presentation. If you absolutely need to create and deliver a presentation that lasts 30, 45, or 60 minutes, you’ll do yourself and your audience a favor by sticking to the 10-minute rule. It simply means that you should build in “soft breaks” to keep the audience from getting too distracted. A soft break can actually serve to reset the audience’s clock. A soft break can include: video clips, stories, another speaker, or audience participation (during a webinar, push out a poll or take questions). Another soft break might be to turn off the slideshow and head to the whiteboard or flip chart to illustrate some concepts. Be as creative as you’d like, but think of it as an ‘intermission,’ between acts. 

Your audience needs a mental break every now and then. Every 10 minutes is a good time to give them one.