Are you something of an octopus? Do you have a tendency to multitask? I'm sure you do. And yes, I know that everyone knows that women are better than men. But the evidence seems to show that actually, women are marginally less bad at it than men on certain types of tasks. But let's understand what multitasking really is.

Multitasking is doing more than one thing simultaneously. And there is an important distinction to be drawn between what I would call plausible and implausible multitasking. plausible multitasking is where you are doing more than one cognitively straightforward task simultaneously. And by cognitively straightforward, I mean something that you can do without really thinking about it. Now, what do you maybe cognitively straightforward may be to me cognitively complex, because I haven't got the experience and the training and the expertise to do it without thinking. So a concert pianist could pick up a little jingle and play it almost without thinking once they've practiced it.

I couldn't, I can't play the piano. So if you've got something that you are so experienced that so well practice that, that you can do it unconsciously, then you've got enough brain capacity to do something else. And if you can do that unconsciously as well, then you can probably do a third thing. So it's possible to walk down the street and chat with your friend and chew gum at the same time without getting hit by a car. But as soon as we introduce one cognitively complex thing, why thing that requires concentration, then you're using up your brain power. And whilst you can continue to do cognitively undemanding things simultaneously, what you can't do is what I call implausible multitasking.

And due to cognitively demanding things simultaneously, your brain can't cope. So what do we do when we do appear to be multitasking on complex things? Well, what we're actually doing is what I would call serial monitor tasking, we do one thing, and then we put it down and do something else. And then we put that down, and we do something else. And we chop and change from one thing to another. Now that's possible, because we're part of our frontal lobes known as broadman.

Area 10th. And this enables us to buffer information. We do something, we stop and put it down and we start the second thing and why would you Doing the second thing broadman area 10 is holding back the information about the first thing. So when we put the second thing down, and go back to the first thing, we remember where we were. And this effect was first noticed at the turn of the 20th century, at the beginning of the 20th century, Kurt Lewin noticed it, and it was investigated by one of his research students bluma zeigarnik. And it's named after her.

It's the zeigarnik effect. It's our ability to hold an incomplete task in our mind. Now, the problem is that our mind is not perfect at retaining the information about the incomplete task, and the knowledge will decay with time. So here's where we start to understand how to optimize multitasking. But before I tell you about that, let me tell you why it doesn't work. And this comes out of the research of three psychologists.

Called Anthony Wagner is here, and Clifford NASS. opia, NASA and Wagner got a bunch of students, and they did some tests on them. But before they did that they divided those students into what I would call the high multitaskers and the low multitaskers. The students who expressed a significant preference for multitasking and try to multitask in their daily work, and students who prefer to do one thing at a time. And in a battery of tests, they found that the higher multitaskers outperformed the low multitaskers on nothing. On all the tests, the students who preferred in their day to day work to do one thing at a time.

And so mono task in all of those tests, they worked more quickly and with fewer errors. It turns out that when we multitask, we information from one task contaminates our reading of the second task. And by having two most heart two tasks running in parallel, our filing system, our mental filing system becomes more disorganized. It takes longer to access information, and we make more errors over NASA and Wagner showed us that multitasking really doesn't work. But other researchers have found that if you're going to try multitasking, there are a number of things you can do to make it as effective as possible. And the first is to be a young adult.

Because it turns out that the peak time for our ability to multitask is in our late teens and early 20s. And little later for men than for women. Now, the other thing is to recognize the pattern of the zeigarnik effect. the decay of information and also the time it takes to switch from one task because switching from task a task B takes time. There is a physical lag as you put down one task physically and move to the next and there is a mental lag as you put down one task mentally and move to the next. Therefore, the faster you chop and change from one task to the other, the more of those lags there are in any time period.

So that suggests that the longer the tasks, the longer the gap between swapping, the more effective it is, but then the zeigarnik effect locks in. And it turns out that the decay of information, the longer the task lengthy is, the more the information about the previous task decays. The sweet spot is around about 20 minutes to half an hour. So ideal mono tasking, do something started, work through it, finish it, put it away, start something else. But if you insist on serial mono tasking, chopping and changing, then spend about 20 minutes on each thing, which is interestingly about the time that we can really concentrate on something for before we need a break. So, multitasking, rule one, don't do it if you can possibly avoid it.

And rule two, if you can't avoid it, and give things around 20 minutes chopping and changing