亲爱的安妮：

    自从两三年前，我所在的部门因裁员而缩水后，我在公司内部就赢得了“千手观音”的雅号，常常同时处理五六个项目，像超人一样飞天遁地。这样的工作方式不仅令人筋疲力尽，而且削弱了我的工作能力。每件事耗费的时间都比我集中火力、逐个击破时要长出很多。

    因此，我决定在新的一年里戒除这种习惯，至少要减少这种情况的发生。问题在于我的老板，他不停地派给我更多工作，用他的话说，就是让我“左右开弓”，而其实我已经比木料场的啄木鸟还要忙了。您或者您的读者能否给点建议，帮我说服他，一次只处理一件事情对我们都会更好吗？

    ——疲惫不堪的人

    亲爱的疲惫不堪的人：

    大量学术研究已经无可置疑地证明，每次将注意力转向别处时，人的大脑都需要时间来重新调整集中。例如，2009年斯坦福大学（Stanford）的一个著名实验发现，一心多用的人“更容易受到无关环境刺激的干扰”，也就是说，更容易分心，处理手头事务的效率更低。

    因此，你觉得同时做几件事情令自己效率低下，这种感觉没错。但是，如果学术研究对你的老板不起作用，那么实现咨询公司（Realization）的首席执行官桑杰夫•古普塔建议用一个快速的小游戏的来证明这一点。

    具体的做法如下：准备一只秒表，或者任何有秒针的手表也行。按下秒表，看看你（或老板）写下“multitask 123456”（英文单词multitask及阿拉伯数字123456——译注）需要多长时间。然后，再按秒表，看看交替写下“m1u2l3t4i5t6a7s8k9”需要多少时间。

    游戏很简单吧？我写下“multitask 123456789”用了9.5秒；而将文字和数字之间轮换着写，花了我24秒，是前者两倍多的时间。

    好吧，或许只是我自己同时处理多任务的能力很差，但是，古普塔表示，即便是多任务处理能手（例如你，也许），在这个游戏的两个结果上，也会出现很大的不同。“结果可能与人们的直觉相反，但是如果让两名员工完成同一个任务，其中集中注意力处理这个任务的员工，总是会比同时处理多个任务的员工完成得更快，错误更少，”古普塔说。

    “许多人在简历和求职面试中夸耀自己的多任务处理能力，”他补充说道。“但是实际上，它无异于告诉人们，‘我做事情没有别人快，没有别人好。’”

    Dear Annie: Since my department was shrunk by layoffs a couple of years ago, I have gotten an in-house reputation as a champion multitasker, able to handle half a dozen projects at one time (and leap tall buildings in a single bound). Working this way is not only exhausting, but I think it makes me less competent. Everything takes much longer than it would if I could just focus on one task at a time.

    So I made a New Year's resolution to cut it out, or at least do less multitasking. The problem is my boss, who is constantly piling more stuff on me to do "with my left hand," as he puts it, when I'm already busier than a woodpecker in a lumberyard. Can you or your readers suggest any way to convince him that we'd all be better off tackling one thing at a time? — Frazzled

    Dear Frazzled: A heap of academic research has demonstrated conclusively that the human brain needs time to refocus every time we turn our attention in a different direction. A famous experiment at Stanford in 2009, for instance, found that multitaskers are "more susceptible to interference from irrelevant environmental stimuli" -- that is, more easily distracted and less efficient at what they're trying to do.

    So your impression that doing several things at once slows you down and trips up your productivity is correct. But if your boss isn't impressed with academic research, Sanjeev Gupta, CEO of consulting firm Realization, suggests a quick game to prove the point.

    Here's how it works: Get a stopwatch, or any watch with a second hand, and time how long it takes you (or your boss) to write "multitask 123456789." Next, time how many seconds it takes to write the same thing, but this time with the numbers interspersed between the letters: "m1u2l3t4i5t6a7s8k9."

    Simple, right? When I tried this, it took me 9.5 seconds to write "multitask 123456789" -- and 24 seconds, or more than twice as long, to write the version that requires switching back and forth from letters to numbers.

    Okay, so maybe I'm just lousy at multitasking but, says Gupta, even master multitaskers (like you, perhaps) will see a dramatic difference. "It seems counter-intuitive, but if you give two employees two identical tasks, the one who focuses on one task at a time will always finish faster and with fewer errors than the one who multitasks," Gupta says.

    "Many people boast about their multitasking prowess on their resumes and in job interviews," he adds. "But in reality, this is like saying, 'I don't get things done as quickly, or as well, as others do.'"