If you’re like most people, you probably take pride in multitasking. You can simultaneously watch TV, check social media channels, text a friend, and listen to music. It may feel as if you’re getting a lot done, but research shows your brain has trouble keeping up.
At the same time, technology has made it easier and more tempting to multitask. “Changes in our electronic environment have changed how we relate to the world and the people in it,” says Dr. Larry Rosen, professor emeritus of psychology, California State University, Dominguez Hills. Yet there is also a cost, says Rosen, co-author of “The Distracted Mind: Ancient Brains in a High-Tech World.”
Not only are we less effective than we think, some neuroscientists believe that multitasking may rewire the brain. If so, how might it change the brain?
Multitasking involves performing two or more activities simultaneously. Certain conditions must be met in order to successfully combine tasks: Both should be simple and they should not use the same mental resources.
We have trouble juggling complex tasks such as driving and texting a friend, but cooking while listening to music is easier. According to Rosen, our ability to do two things at once depends on the prefrontal cortex, the brain area involved in executive function. The prefrontal area determines how we perform tasks and in what order we execute them. An automatic activity, like walking, demands less of the prefrontal area than reading or playing an instrument. It’s harder to combine two demanding tasks, such as driving and talking on your cellphone.
Most multitasking is actually serial tasking. “We don’t multitask,” says Rosen. “What our brains are doing is task-switching.” For example, if you are looking at your computer while texting a friend, you are not really doing both simultaneously, but rapidly shifting your focus back and forth. It may feel instantaneous, but there is a lag time as your brain disengages from one task and reengages in another.
“You use working memory to keep track of what steps are involved,” explains Dr. Arthur Markman, professor of psychology at the University of Texas at Austin. “When you shift away, your working memory gets filled up with information from the second task.” Each time you switch gears, part of your mind remains on the previous activity. When you shift back, you’ve lost your place. Our brains were not built to multitask.
“Your brain has a finite amount of resources,” says Rosen. It’s a “serial-processing computer” rather than a parallel-processing one. When there are not enough resources to go around, performance suffers.
Most studies confirm that multitasking makes us slower and less accurate — but there are exceptions. In fact, about 2 percent of people excel at task management. Known as “supertaskers,” some people are wired to multitask.
This unique group was discovered by Drs. David Strayer and Jason Watson, psychologists at the University of Utah, who were studying why talking on a cellphone while driving is dangerous. They gave participants a driving-simulation task and tracked the number of mistakes people made while chatting on a mobile device. Surprisingly, about two people out of 100 could handle both without a decrease in performance.
“If you are doing two things at once, you get worse at both of them,” says Markman. “We have become masterful in turning 45 minutes into four hours,” he says. “It takes more time to complete the task, and the more multitasking you do, the more error prone you become.”