How to Stop Multitasking

Doing too many things at once is like giving up ten IQ points—and a bunch of other scary stuff, warns Peter Bregman

By Peter Bregman

Posted on Harvard Business Review: May 20, 2010 2:40 PM

During a conference call with the executive committee of a nonprofit board on which I sit I decided to send an email to a client.

I know, I know. You'd think I'd have learned.

Last week I wrote about the dangers of using a cell phone while driving. Multitasking is dangerous. And so I proposed a way to stop.

But when I sent that email, I wasn't in a car. I was safe at my desk. What could go wrong?

Well, I sent the client the message. Then I had to send him another one, this time with the attachment I had forgotten to append. Finally, my third email to him explained why that attachment wasn't what he was expecting. When I eventually refocused on the call, I realized I hadn't heard a question the Chair of the Board had asked me.

I swear I wasn't smoking anything. But I might as well have been. A study showed that people distracted by incoming email and phone calls saw a 10-point fall in their IQs. What's the impact of a 10-point drop? The same as losing a night of sleep. More than twice the effect of smoking marijuana.

Doing several things at once is a trick we play on ourselves, thinking we're getting more done. In reality, our productivity goes down by as much as 40%. We don't actually multitask. We switch-task, rapidly shifting from one thing to another, interrupting ourselves unproductively, and losing time in the process.

You might think you're different, that you've done it so much you've become good at it. Practice makes perfect and all that.

But you'd be wrong. Research shows that heavy multitaskers are less competent at doing several things at once than light multitaskers. In other words, in contrast to almost everything else in your life, the more you multitask, the worse you are at it. Practice, in this case, works against you.

I decided to do an experiment. For one week I would do no multitasking and see what happened. What techniques would help? Could I sustain a focus on one thing at a time for that long?

For the most part, I succeeded. If I was on the phone, all I did was talk or listen on the phone. In a meeting I did nothing but focus on the meeting. Any interruptions—email, a knock on the door—I held off until I finished what I was working on.

During the week I discovered six things:

First, it was delightful. I noticed this most dramatically when I was with my children. I shut my cell phone off and found myself much more deeply engaged and present with them. I never realized how significantly a short moment of checking my email disengaged me from the people and things right there in front of me. Don't laugh, but I actually—for the first time in a while—noticed the beauty of leaves blowing in the wind.

Second, I made significant progress on challenging projects, the kind that—like writing or strategizing—require thought and persistence. The kind I usually try to distract myself from. I stayed with each project when it got hard, and experienced a number of breakthroughs.

Third, my stress dropped dramatically. Research shows that multitasking isn't just inefficient, it's stressful. And I found that to be true. It was a relief to do only one thing at a time. I felt liberated from the strain of keeping so many balls in the air at each moment. It felt reassuring to finish one thing before going to the next.

Fourth, I lost all patience for things I felt were not a good use of my time.