When I was a student, I used to be able to do a Russian translation and follow a play on the radio at the same time. Over the years, my capacity for multi-tasking has dwindled to almost nothing: these days even scrolling through Facebook with the Today programme on in the background makes my brain ache. Apparently, feeling drained by multi-tasking is scientifically explained by it using up oxygenated glucose, and it certainly makes sense to me that doing two things at once is more demanding than doing one at a time. When we choose to do it, it’s not because it’s more efficient, it’s usually because we want some inducement to get on with something that’s quite hard work.
However, it’s only a strain when the two tasks are similar (both cognitive or both physical): listening to the radio while I’m washing up or ironing is a completely different matter. As the BBC’s Claudia Hammond points out, “If the tasks are different enough then multi-tasking can even improve your performance”. What helps and what hinders us varies from individual to individual, as well as on the intensity of the tasks. According to Ms Hammond’s article, about 2% of the population are natural multi-taskers, while for the rest of us performance can benefit from it sometimes and suffer at other times, depending what we’re trying to do.
Most people find it easy to walk and think at the same time. In Thinking, Fast and Slow, Daniel Kahneman says, “Indeed, I suspect that the mild physical arousal of the walk may spill over into greater mental alertness”. Yet when the task is to walk as fast as possible, it is much more difficult to think coherently. Conversely, if the mental task is too taxing, we stop walking because all our energy is focused on solving the question we’re thinking about.
Now let’s introduce stress. Putting aside any flashes of genius that have come to people whose backs were hard up against the wall, I imagine most of us would agree that, under pressure, we don’t think as clearly and as well as we do when we’re relaxed. If this is true anyway, how much more challenging is it to be multi-tasking under pressure?
The reason I’m discussing this here is, of course, to relate it to public speaking. If you’ve never looked at it this way before, here is the truth: expressing yourself coherently is one task; connecting with your audience is another. Yes, in everyday conversation we achieve both simultaneously without turning a hair – but don’t underestimate how different it is when you’re the only one speaking, a) for an unnaturally long time and b) to a big group.
Some degree of multi-tasking is unavoidable (even desirable) in the normal course of work and home life. When you’re making a speech or presentation, however, there is no room for multi-tasking. If you’re trying to find the right words at the same time as you’re trying to connect with your listeners, one or other task will suffer. It’s usually the latter, meaning all the effort going into the former will be largely wasted, since the audience won’t be listening. Where a speaker favours connection over finding the right words, the risk is of saying something he/she will regret.
And let’s not forget, a modern audience is accustomed to multi-tasking. If they’re not fully engaged with the talk, they will soon be surreptitiously checking their messages, possibly believing they are still listening, though actually they will retain little or nothing of what the speaker is working so hard to tell them. If you don’t want your audience to be multi-tasking, you mustn’t be doing it either! The cognitive effort to work out exactly what you want to say needs to be made in advance, so that on the day you’re free to concentrate entirely on the all-important task of connecting and communicating with the people in front of you.