Kill lecture boredom through science
One way to think about public speaking is that’s it’s a game of attention. You have to keep people’s attention in order for them to learn anything from you. Lose their attention and it’s game over.
But most things that earn people’s attention are annoying. I could stand at the front of the room and set off the fire alarm every 5 minutes. They’d hate me, but boy, I’d sure have their attention. What we really want is positive attention.
One great nugget comes from Bligh’s book, What’s the use of lectures? There he explains exactly how long most people’s attention spans probably are. This chart shows an audience’s average heart rate over time:
This chart show exactly what happens while you’re speaking – people’s heart rates decline. They are getting bored and there is a break point at about 25 minutes.
This data comes from a small study of 16 students, over four different lectures. Not a huge study, but the best data I’ve seen on boredom (See page 51 of Bligh’s book)
What does this mean? Two things:
- 20 to 30 minutes is a sweet spot amount of time for lectures (No surprise TED and GEL use this format).
- If you go longer, do something different every 20 minutes to regain people’s attention.
The problem is, most speakers don’t know how to do anything but straight on, monotone, bullet list heavy, lecturing. We do not have another thing we know how to do in front of an audience.
The ideal thing would be go interactive. Have the audience do an exercise, answer a question, watch a movie, or move their bodies in some way every 20 minutes. But this requires planning and skills most speakers do not have.
If you are asked to speak longer than 20 minutes, plan breakpoints. Stop every 20 or 25 minutes and ask the audience if they have a question. Or better yet, ask them a question for a show of hands. Give them a challenging problem to solve, or show a short film, do a dance, or move to a new spot on the stage. Anything to help reset their attention cycles.