Why multitasking is impossible

It seems that we can do several things at once. When we are at home, most of us can talk on the phone while we are organizing the closet or preparing something in the kitchen. Or if we are attending a work meeting, we believe that we can follow what is being said while we keep an eye on our messages. It seems that this apparent multitasking ability is even more developed in young people, who grew up with cellphones. Or in working mothers, who manage to address several issues at the same time. However, that is not the case. Although we may seem to be, we are not multitaskers. Our brain is incapable of paying attention to several things at once, as science has shown. We can only have one or two thoughts at a time, according to Earl Miller, renowned neuroscientist at Massachusetts Institute of Technology (MIT). We could say that we really are “jugglers” or “kangaroos” because we jump, more or less quickly, from one task to another. But this skill takes a considerable toll on us, on our mental health, and on our effectiveness.

In 2001, researchers discovered the default mode network that is activated in our brain when we are not doing anything. And it was discovered almost by chance. Marcus Raichle of the University of Washington was measuring via MRI scanners what was happening in the brains of volunteers while they did various activities. Between each of the tasks, they remained lying down, still and possibly bored. When they stopped doing what the researchers asked, the volunteers relaxed or simply gazed out into space. It was at this moment that two things were observed: first, the area of the brain that was in use when tasks were being carried out deactivated. Second, suddenly and surprisingly, another different area would light up in the MRI, even though the person was completely calm.

Since then, this circuit — which wakes us up when we are relaxed or simply doing “nothing” — has been examined in further detail. In turns out that the default mode network is largely responsible for creativity and the proper consolidation of ideas. However, when we are in the culture of super-efficiency, our brain does not have time to consolidate what it has learned or to reach deeper thoughts. And, as you can imagine, the default mode network cannot be activated in our brain if we are multitasking. But the consequences go beyond that.

Multitasking can lead to memory failures. For example, when we are talking on the phone while parking the car, we may have problems remembering later where we left the car. Or if we are talking, and we close the door to our home, we may question later whether we locked it. Memory is affected and so is our effectiveness, which can be very dangerous depending on the task at hand. At the University of Utah, researchers measured our driving ability while paying attention to cellphones. And the conclusion is devastating: our attention drops so much that we are as dangerous behind the wheel as if we had high doses of alcohol in our bodies. And while not extreme, if we are distracted in a meeting because we are doing something else, it will be more difficult for us to remember what has been said, and we will probably not respond very well if questioned. Furthermore, this extra effort that we ask of ourselves has a medium-term consequence: mental exhaustion and a feeling of tiredness. Hence, the best way to recover from an intense week is to stop multitasking, enjoy a single activity and reduce the demand of having to give more. And all this for a purely neurological question.

Our brain acts the same way it did 40,000 years ago, when we were not surrounded by current technology. Our mental processes are not prepared for so much information or for doing several things at once that require a minimum of attention (logically, this does not apply to tasks that relax us, such as working or reading with music playing in the background; nor to automatic tasks, such as walking, breathing...). Smartphones are possibly the biggest distractors and the main source of multitasking, and it is up to us to find a way to control how we use them.

To do this, we must accept a reality: if we want to be effective, have better recall and not burn out, we need to focus our attention on just one thing. The price of multitasking is too high, even if it has become a habit. Therefore, we need to relearn our habits, to set time limits. We can focus on doing something for 10 minutes and then spend a minute resting, distracting ourselves with whatever we want. But we need to stop straining our concentration to the max because it has a limit and when we abuse it, we pay for it in the medium or long term.

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