I’m the kind of person who permanently has at least 10 windows open on my computer, at the same time as I hold a conversation, listen to the radio and send texts. I insist that I can concentrate perfectly well on all these things, but looking at the evidence, to be honest, I probably can’t.

The truth is that if you think you are good at multi-tasking, the chances are you’re not. People who multi-task a lot perform less well in tests than people who don’t do it so often. In other words, practice does not make perfect. But there are some exceptions: a select group of individuals, accidentally discovered by psychologists, can cope with several tasks at a time, and can even do better the more their attention is divided. They have been dubbed the supertaskers. 

David Strayer and Jason Watson, cognitive neuroscientists from the University of Utah and the University of Colorado Denver, were researching what happens when people sat at a driving simulator while chatting on a hands-free phone. Just to make it harder, as well as remaining a prescribed distance from the car in front, they had to memorise a list of words, interspersed with mental arithmetic problems.

One person outperformed everyone else. Whatever the distraction, this individual just seemed to deal with it  

Not surprisingly people weren’t very good at it. The distractions slowed their reaction times and dented the quality of their driving. Except for one person, who outperformed everyone else. Whatever the distraction, this individual just seemed to deal with it. The psychologists rechecked the figures. There had been no mistake.

But they did wonder whether it was some kind of fluke. So they tested another 200 people. A total of 97% of people failed the test. But they found another four whose performance wasn’t diminished when they multi-tasked. This left the researchers with a total of five of these special people – three men and two women. They’ve dubbed this exceptional 2.5% of the population “the supertaskers”.

Decades of research in cognitive science have shown that our attention is limited. We are able to concentrate on a few different things at a time, but add in one extra distraction and we stop doing so well. Our cognitive resources have to be shared between the different tasks and something has to give. There’s plenty of good evidence that talking on a mobile phone causes drivers to fail to notice half of the things going on in their environment, reduces their reaction times and unsurprisingly,  increases accident rates. Yet a tiny percentage of people seem unaffected.

So how do they do it?  Is there something special about the brains of these supertaskers that allows that them to divide their attention without denting their performance?

When we practise a skill, the brain becomes more efficient and shows less, rather than more activity  

You might expect the regions of the brain devoted to attention and cognitive processing to become super-active during these multi-tasking tests. But when supertaskers were put in fMRI scanners in 2015, this isn’t what the scans showed. There was less activity, rather than more in areas which would expect to be busy, such as the prefrontal cortex and the anterior cingulate cortex.

This might seem surprising, but there are two reasons for it. When we practise a skill, the brain becomes more efficient and shows less, rather than more activity. The brains of golfers, archers, and racing drivers, for example, show less activity when they lie in a brain scanner doing mental tasks related to their expertise, than the brains of non-experts.

And this is where it gets really interesting. As well as this increase in efficiency, the distribution of activity in the brain changes, and although there might be less activity in areas associated with attention, there is increased activity in the default mode network – the regions of the brain that are busy when we’re daydreaming, or reminiscing or contemplating the future. 

We don’t yet know whether supertasking brings any disadvantages  

Supertaskers can juggle multiple tasks because their brains are wired for more efficiency. It would be a mistake to think that more brain activity always means better. The more they had to do, the more efficient they became. Yet these people had no idea they had this special skill. And so far, little is known about how this skill might affect them in everyday life. The next thing Watson wants to discover is whether supertaskers are attracted to or excel at particular kinds of jobs.

We don’t yet know whether supertasking brings any disadvantages. Could this amazing ability to concentrate on lots of different tasks come at the expense of something else? There’s also the question of why it’s such a rare skill. Watson speculates that maybe the reason so few people have evolved to supertask, is that it’s a skill that’s only recently become useful, with the advent of modern technology.

Can you learn to supertask? Probably not. You can certainly practise different tasks and improve your performance on each one, but that doesn’t mean you’ll get better at doing them all simultaneously.  

By now you might be wondering if you could be a supertasker. A team at the University of Tasmania and the University of Utah developed a test for the BBC.

You need to use a computer, not a phone or tablet. And I have to warn you that even the instructions are difficult, let alone the test itself. There are three doors on a screen which open in a random order. Your task is to remember which door opened the time before last. You get a visual and audio version at the same time, requiring you to hold four pieces of information in mind at a time. It sounds relatively simple. But it isn’t, or not to me anyway. And it takes about 40 minutes to get through it. It’s best to choose a time when you can really concentrate.

I made the mistake of trying it in the middle of a noisy office. Once I’d worked out what you had to, it got better and I was almost but not quite a supertasker. To be honest even under exam conditions I’m not sure I would have succeeded. But after listening to my recent BBC radio programme on the topic, 1,200 listeners gave it a try, and 2% were supertaskers. A few even emailed me to say it was easy.

Give it a try yourself, and let us know how you go on BBC Future’s Facebook page… just try not to get distracted on the way.

Listen to the BBC radio programme All in the Mind about supertaskers.

Read more: Why your brain likes it when you multi-task

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