September 24, 2017
Connected to all who are important in her life
Expert Q&A

Can Your Brain Really Multitask?

by Peter Jaret  |  

Co-author of the 2016 book The Distracted Mind: Ancient Brains in a High-Tech World, Adam Gazzaley, MD, PhD, is a professor of neurology, physiology, and psychiatry at the University of California, San Francisco. His lab has done groundbreaking work on how the brain responds to distractions and the modern world’s constant pressure to multitask. Gazzaley talked with us about the clash between what our brains can do and the demands of today’s high-tech information revolution.

A lot of us think we’re pretty good at multitasking. What does your research show?

We’re fooling ourselves. There are real limits to our cognitive abilities: to our ability to focus our attention, our ability to maintain information in the mind—something we call working memory—and our ability to switch from one task to another, or multitask. The unprecedented exposure to and access to information that technology provides today means we’re constantly being distracted—by email notifications, vibrating cellphones, computer pings. We live in a world of distractions. We think we can manage it all. But there’s a disconnect between what we want to do, and think we can do, and what the brain is actually able to do.

What happens in the brain when we try to do too many things at once?

In our laboratory, we record brain activity and accuracy and response time on different tests while our participants are being distracted or trying to perform multiple tasks at the same time. In that setting, we see a significant degradation in performance and accuracy, even in young adults, when people try to multitask. Performance and accuracy get worse as you get older, even among healthy older people. What brain scans show is that when we are focused on one thing, we activate a complex network of neurons. When we shift our attention to something else, that network is decreased and a new network is engaged. And with each switch, there is a loss in performance and accuracy. The brain isn’t built to parallel process; it needs to switch attention from one thing to another. There’s also evidence from the real world. For example, we know that talking on the phone or texting while driving is dangerous because the brain can’t fully attend to both activities.

And yet we seem increasingly addicted to these distractions. Why?

All these devices give us unprecedented access to information. And information is critical to our survival. Hunter-gatherers foraged for food. Today, we forage for information, which is just as crucial to our survival in the modern world. So it’s not surprising that we seem to be addicted to technologies that provide information. But there’s a cost. One of the things that distinguishes the human brain is our ability to set very high-level goals, and to have multiple goals, all interconnected. You can think of that as top-down control. But we also evolved, like other animals, to respond instantly to what’s going on around us, also known as bottom-up stimuli. Increasingly, we’re being distracted by bottom-up information, from email notifications to calendar reminders. We are very sensitive to this kind of bottom-up stimuli. Unfortunately, too much of it distracts us from our higher-level, top-down goals—writing a paper, or learning a new skill, for example.

Today’s constant access to information also creates a sense of anxiety, the worry that you’re going to miss something if you don’t constantly check your email or social media. And that has also created an intolerance to boredom. People used to wait in line at the checkout and daydream. Now they pull out their phones and go right back into the digital world. This is a missed opportunity to reflect, to relax, to be mindful of the moment. Creativity really lives in those quiet silent spaces. If you don’t have them, if your day is constantly filled with more inbound information, you miss valuable opportunities.

What can we do to resist the negative impact of too much information?

Be aware that you really can’t effectively multitask, even if you think you can. Be aware of how pushy your technologies are. Do you really need everything flashing on your screen as a notification? Do you really need your phone pinging each time a text comes in? Notice when you feel anxious because you haven’t checked your email or social media. Notice when you feel bored. Once you’re aware of the effect of these information technologies, you may feel a lot more motivated to change what you don’t like. Then take control of what you devote your attention to. When you’re doing a critical activity that you know requires your highest level of performance or attention—not just a project at work but also, say, talking to your children or spouse—turn off your cell phone. Shut off email notifications. Limit the distractions. And set boundaries for yourself. Set aside time when people know you won’t be available by email or phone. Most people, when they begin to set boundaries, realize that they can go for a few hours or even a day or a week without missing something critical. Once you begin to free yourself from the constant distractions, you begin to understand that most of the information wasn’t important in the first place. And it helps to learn to tolerate boredom, to value quiet time, to take breaks and be mindful of the moment.

You mentioned limits to what the brain can do. But can our brains eventually adapt to the new demands we place on them—to multitask more effectively, for instance?

We’re very interested in that possibility. In fact, we’re developing video games designed to enhance specific cognitive abilities, like the ability to switch attention from one thing to another. The human brain is very plastic. It can modify itself at every level in response to experiences. So we’re building video games that provide targeted experiences, then doing careful studies to see what impact they have on other cognitive abilities, outside of the game itself. And we’re even looking beyond that to see how the experience of using these video games affects stress, inflammation, mood, sleep, and physiological markers such as hormones. We think video games will be useful as therapies and also as tools in education. So yes, I think our brains can adapt to better handle the unprecedented amount of information available to us. But I think it’s also important to adapt our behavior, to be much more in control of these technologies and the demands they make on our attention.

Also see Does Your Life Have Purpose?