I was reading Happiness By Design by Paul Dolan when I came across a section on multi-tasking. Mr Dolan explains that switching from one task to another causes a form of cognitive friction and should be avoided if possible. You should, to maximise pleasure and purpose, concentrate on one task at a time. Then he says this about slide-based presentations:
“Multitasking takes effort and it’s not worth it. I never use lecture slides for this reason: students don’t waste their attentional resources going between the slides and my voice.”
This is interesting.
I clearly think Mr Dolan is wrong about using slides, I find them useful, but we agree about a larger point - you have to consider your audience’s attention.
I suspect, for instance, that Mr Dolan wouldn’t say that movies or television programmes impose too great a cognitive load to be pleasurable or purposeful. He’s probably not advocating listening to radio plays instead, perhaps followed by half an hour looking at photos of the cast. That would be silly. That’s because we think of watching a movie as doing one, singular thing, it’s one activity not 90 minutes of multitasking. And we treat it as one thing because it’s designed as one thing. The movie-maker consciously directs and designs your attention so it doesn’t feel like a cognitive drag to watch the pictures as well as listen to the music.
We should think of presentations in the same way. We should design them to be singular things that combine, thoughtfully, the words that come out of your mouth with the stuff that comes off the screen (see Giles’ post about the ingredients of presentations). We should reduce the switching costs for the viewer by actively managing their attention.
If, as is common in academe, the slides are just notes for the talk then Mr Dolan is also right, sticking them on the screen might not help. But that’s not because of some deep cognitive truth, that’s because of the laziness of the presenter.
@undermanager - 20 April 2017