Supertaskers: Why Some Can Do Two Things at Once

Multitasking has become a way of life. Most of us think nothing of juggling a couple of chores at once, whether at home or in the office or, most dangerously, on the road. And despite some states’ bans on talking while driving, as well as a raft of studies showing the potential deadliness of distracted driving, chances are good that you still have cell-phone conversations behind the wheel.

Chances are also good that you think it’s O.K. because you’re a truly capable multitasker. Maybe you even consider yourself one of the few supertaskers who, unlike the rest of us, are so mentally agile that they can safely talk or text — or pen a novel — while driving.

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A new University of Utah study on distraction in the driver’s seat finds that such virtuosos do exist: the paper, which has been accepted for publication this year in the journal Psychonomic Bulletin & Review, found that a very small percentage of participants — 2.5% to be exact — were able to do other things successfully while driving (in the study, it was solving math problems and memorizing words) without a drop in performance on any task. In fact, some of these supertaskers performed better while multitasking than they did while completing the tasks alone.

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The authors of the study suggest that there may be a set of biological, genetic and perhaps behavioral factors that contribute to efficient multitasking, and that maybe some of these factors can even be learned to make the rest of us better at doing two things at once.

Jason Watson and David Strayer, psychologists at the University of Utah, assembled a group of 200 undergraduates and asked them to perform a simulated driving test as well as a standardized memory test that involved math and word memorization. Each of the students first performed these tasks separately, then simultaneously. For the multitasking portion of the experiment, researchers asked the volunteers to complete a verbal version of the memory test on a hands-free cell phone while driving in a simulator.

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During the hour-and-a-half session, 97.5% of the students showed a significant decrease in their driving abilities and memory skills while multitasking. “What we think is happening for most of us when we multitask is that it’s more than what our mental capacity, or mental resources in the frontal cortex, can handle,” says Watson. The frontal cortex acts as a master switching station that manages where the brain focuses its immediate attention. “So our performance is going to suffer when we combine different tasks.”

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But a minority of students in Watson and Strayer’s study — the other 2.5% — showed no declines in performance, and in some cases even logged an overall improvement in ability when various tasks were combined. This is the small subset of individuals whom the authors call supertaskers, whose brains seem to function differently from those of the rest of us.

Supertaskers can juggle simultaneous tasks without experiencing a drop in attention or focus, which flies against the conventional wisdom about how the human brain functions. Experts believe that the brain has a fixed budget of resources, with demands on its attention serving as expenses. Given the limited neuronal budget, the brain can devote only so much of its resources to any particular task; if demanding tasks pile up on each other, then each task is allotted a smaller and smaller amount of resources, which translates into a decrease in performance.

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This is what happens when we talk and drive — our cell-phone conversation diverts attention away from the road, so our driving ability suffers. In fact, in the study, the scientists found that the majority of students took 20% longer to brake while using a cell phone, and let their following distance behind a pace car stretch out 30%, compared to when they were not talking on the phone.

Watson and Strayer are now following up their work with more intensive analysis of the brain function of these supertaskers. Not only are they talented multitaskers, says Watson, but they also seem to perform better than others on memory tests to begin with. He and his team are now imaging the brains of these individuals while they complete such tasks, and are comparing their neural activity to that of non-supertaskers to ferret out any biological or genetic differences that might explain their unique abilities.

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It’s possible that supertaskers are tapping into several other mental mechanisms to maintain performance. For instance, they may be able to focus on multiple tasks simultaneously simply by better allocating their attention — in other words, they may be able to triage information as it comes in, disregarding irrelevant and distracting information and focusing only on the inputs that are critical to performing a given task.

That’s what Daphne Bavelier, a professor in the Department of Brain and Cognitive Sciences at the University of Rochester, thinks might be occurring in the supertasker equivalents she has seen in her lab. Bavelier studies the effect of action-video-game playing on people’s ability to split attention and multitask. In her work, she has found that people who devote five hours or more per week to such action games for a year show the same heightened performance abilities as Watson and Strayer’s supertaskers.

Bavelier is now conducting further studies of these individuals to figure out why their multitasking abilities improved and whether the skill can be learned by other people. “Possibly, their allocation of resources is more flexible and more targeted to the type of information that is immediately relevant,” she says. “They might be less distracted by irrelevant noise and therefore able to put more of their resources toward the task at hand.”

Both Bavelier and the Utah scientists are interested in performing more long-term studies of young children, who, thanks to advances in technology, seem to be naturally more adept at multitasking — texting, talking, listening to music and doing their homework all at once — than previous generations. The researchers are especially eager to find out whether supertasking can be trained or learned, and to see if the average person can enhance his or her multitasking ability simply through practice.

Watson, for one, believes it’s possible, especially in children whose everyday environment makes them increasingly proficient at splitting their attention among tasks. But for the time being, he’s not urging people to train themselves by chatting on the phone while driving. “Most of us are in the 97.5% who will be impaired when we talk and drive,” he says. Even if we think we aren’t.

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