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.”
In addition, studies have shown that people who consider themselves great at multitasking are actually the worst at it. Self-reported heavy multitaskers remember less information and make more errors than light multitaskers. Scientists believe this may be because they are unable to filter out irrelevant details.
So, why do we do it? “We think we are better multitaskers than we are,” says Rosen. We want to believe we are the exception. It’s also hard to resist the temptation to let our minds wander. Even when we know we should concentrate our attention on a task, most people enjoy a distraction.
A BAD RAP?
While single-tasking is often considered to be more effective, some research suggests there could be a benefit to the distraction afforded by multitasking.
A study by Drs. Kelvin Lui and Alan Wong at the Chinese University of Hong Kong tested whether frequent media multitaskers might be better at integrating information from different senses, such as sight and hearing. They asked participants aged 19 to 28 to perform a visual search task, with or without a sound that helped find the right item. People who spent more time on multiple devices (such as using a tablet while watching TV) performed better when the tone was present and worse when it was not.
The authors concluded that media multitaskers are better at detecting information coming in through their eyes and ears. Using our faculties in this way could certainly be useful in modern life. Some studies report the opposite, however, instead showing that using various media impairs working memory. Frequent multitaskers may also be more easily distracted.
Other studies suggest that multitasking may even be harmful to the brain. In one experiment, neuroscientists at the University of Sussex, England, used brain scans to show that multitaskers had less gray matter in the anterior cingulate cortex. This is the part of the brain that influences empathy, sensory perception, and emotional control. It is unclear, however, whether technological multitasking changes our brain structure, or whether people with less gray matter are more impulsive and thus prone to multitasking.
Jumping from task to task also has an effect on your body. Repeatedly switching tasks leads to anxiety and an increased production of the stress-hormone cortisol in the brain. This is mentally draining and can leave you feeling fatigued.
Multitasking is nothing new, of course, but technology has added a new dimension. At any given moment, streams of information come at us from different sources, demanding our attention. “We live in a world where our phone has us stressed,” says Rosen. “If we don’t take back control, we’ll be beset by anxiety.”
RECLAIM YOUR ATTENTION
“There is a constant invitation to pay attention to some new piece of information in the environment,” says Markman. In our “permanent state of distraction,” he says the brain learns to expect an interruption. Even during our downtime, we might find ourselves texting a friend.
The long-term effects of multitasking are not well understood. Nevertheless, it is probably a good idea to stop the multitasking habit if you want to perform your best. “The important thing is learning how to reclaim our attention,” says Rosen. He suggests taking a “tech break” to satisfy the urge to check your device.
TAKE A TECH BREAK
When you are working or studying, set an alarm on your phone or computer for 15 minutes. After 15 minutes of working, give yourself one minute to check everything. Then continue your work uninterrupted. Gradually extend this to 30 minutes at a stretch. With practice, we can cultivate better habits. By learning to balance the benefits and drawbacks of technology, we can also protect one of our most precious resources: time.