My wife tells me I can only do one thing at a time. That's fair. I'm not great at multitasking. But, according to new research, neither is she. In fact, some research suggests I'm probably better at it than she is.
How could this be? That's exactly what she wanted to know.
Researchers at the University of Utah wanted to know why people text and drive despite warnings that texting impairs driving about as much as being drunk.
One theory was that people who text and drive are simply unable to resist the temptation to do it. They tend to be risk-takers. And, by the way, they think they can handle multitasking even if others can't.
The researchers recruited students for a study. They asked the students about their texting and driving habits, and whether they were good at multitasking. To prove their multitasking ability, the students had to solve math problems while also remembering a series of letters.
The results? Those who reported multitasking the most and thought they were the best at it were actually the worst. (It was with great satisfaction that I waved this study at my wife. "Take that!" Not my proudest moment.)
Similar findings have been reported by other researchers. One study from Stanford University was published in 2009. It found that people who rated themselves as great multitaskers were terrible at it. Not only did they make more mistakes than non-multitaskers, they took longer to get things done.
The idea that women are better multitaskers than men has reached the status of conventional wisdom. But it may also be wrong. In a 2013 study published in Psychological Science, men were actually better multitaskers than women. The difference was attributed to the men having better spatial ability. Regardless of gender, better multitaskers tended to have better executive function (the ability to remember and revise goals based on updated information). Interestingly, during certain phases of the female menstrual cycle, the performance of women in this study equaled that of men.
Then again, other studies using different types of tasks have found that women were better than men at multitasking. Taken together, it seems that a person’s ability to multitask might be affected by a number of factors including gender, phase of the menstrual cycle, cognitive capacity (especially executive function and spatial ability), and the type of tasks performed.
Defining multitasking isn't as simple as you may think. In fact, what we think we're doing when we multitask is actually "serial tasking." That is, we may think we're doing several things at once – reading an e-mail, answering the phone and editing a document – but we're actually doing one thing at a time, and simply moving between tasks repeatedly.
But here's the rub: There's a cost to this. Each time we shift our focus from one task to the next, it takes time for the brain to catch up. Some experts have estimated that it takes up to 40% more time for people to complete several tasks when they are serial tasking (call it multitasking, if you must, but you now know better) than if they completed these same tasks one at a time.
Even more compelling are the real-world studies of employees who are more productive when turning off their e-mail screens. And I can't help wondering if my kids would retain more when they study if they turned off their phones and other distractions. I suspect someone has already done that experiment.
You may still be skeptical about the downsides of multitasking. I admit that experiments of students doing math problems while remembering a series of letters don't exactly reflect what most multitaskers actually do. It's certainly not the same as talking on a cell phone while driving.
So, could there be some good multitaskers out there who can actually handle texting and driving? Maybe, but they are probably a rare breed. And it's probably not you or me.
The evidence suggests that the idea that there are good and bad multitaskers is a myth. In fact, the entire concept of multitasking may be a myth; we are all just serially tasking as well as we can.
So, don't fall for the misconception that you can handle several tasks at once. It's good to look busy – and it's good to be busy. But it's not good to lose efficiency by trying to do too much at once, especially if you're driving.
Robert H. Shmerling, M.D., is associate physician at Beth Israel Deaconess Medical Center and associate professor at Harvard Medical School. He has been a practicing rheumatologist for over 20 years at Beth Israel Deaconess Medical Center. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program.