神经科学家：同时执行多任务处理不可取

很多人希望同时干好多项工作，但科学家人为，人脑的设计并不支持多任务处理。

本文属于“交易工具”专栏，该专栏每周一期，就习惯养成或融资等各项任务如何实现快速有效的结果，邀请各领域的专家分享可行的建议。

本周的专家是麻省理工学院Picower学习与记忆中心的神经科学教授厄尔·米勒。他将为我们解析进行多任务处理是不可取的。

下面是一位神经科学家的可行建议： 不要尝试多任务处理。因为它会降低工作效率，导致错误连篇，妨碍创造性思维。许多人可能会想：“我很擅长多任务处理！”很可惜，这只是幻觉而已。人类同步思考的能力极其有限——在某一个时刻，我们只能保存少量的信息。

但我们的大脑却会欺骗我们，让我们以为自己可以做得更多。要想了解背后的原因，我们不妨想想人眼如何观察世界。除了有视觉障碍的人外，我们都是在透过一个类似于视频摄像机的广角镜头来感知周围的环境。或者，至少看起来是这样。事实上，我们的眼睛一直在以每秒3-4次的速度扫视周围，记录下周围环境的片段。我们以为自己看到的是一幅完整的图像，但这只是因为大脑将这些独立的片段整合在了一起，才形成了一个完整的画面。

多任务处理也是同样的道理。当我们同时处理多个任务时，整个过程看起来是无缝衔接的，但事实上，它也需要有一系列小的变化。假如你正在为客户写一份营销文案，但中间不得不停下来查收邮件，当你重新回到文案工作上时，你的大脑必须付出宝贵的脑力，让自己重新集中精力执行这项任务，查看已经完成的内容和修改错误。这不仅浪费时间，也会影响创造力。毕竟，创新思维来自于长时间的精力集中，即沿着一个新道路网络，遵循一种理念的能力。当你尝试进行多任务处理时，你通常很难在一条道路上走的足够远，也就无法产生一些新颖的想法，因为你总是在改变和回溯。

如果你认为“这或许只适用于其他人”——这也是错误的。事实上，研究表明，认为自己擅长多任务处理的人，同步思维能力往往更低。这是合理化的集会。经常犯罪的人不擅长忽视分心的事情，相反，他们会努力提高专注力，他们让自己相信，多任务处理能够提高工作效率。

或许你会想：“既然多任务处理是不可取的，为什么我们还是会迫不及待地想要去这样做呢？”答案或许与人脑的进化过程有关。早在史前时代，任何信息都可能生死攸关——例如，灌木丛里的沙沙响声，可能意味着即将有一只老虎猛扑出来。所以，我们的大脑会适应性地寻找和关注新的信息。很可惜，曾经的进化优势，如今却变成了让人们注意力分散的根源。在当今的现代社会，我们的生命很少会受到威胁，但无休止的信息轰炸却可能削弱我们的能力。人脑并非设计用来处理这些超负荷的感官刺激。

下文将告诉你如何解决这个问题。

首先，拿出一段保持专注的时间。消除尽可能多的让人分心的事情： 拿走手机，关上额外的电脑屏幕，如果有必要，关上电子邮件。不要单纯依靠自己的毅力进行单任务处理； 我们很难抑制对新信息的渴望。相反，我们应该通过消除诱惑来避免内心的冲动。如果你发现自己很难集中精力，可以尝试休息一下，站起来走走。增加大脑血液循环，可以帮助我们恢复专注。

最后的一条建议是： 在开车的时候，请务必放下手机。把手机调成静音模式，放在手拿不到的地方。（免提耳机也没有帮助； 因为导致分心的是对于对话的认知需求。以为自己可以一边开车一边打电话，是另外一种幻觉——戴维·斯泰尔与其同事的研究显示，边开车边打电话，会使司机忽略前方一半的事物。开车时进行多任务处理，是非常危险的。 （财富中文网）

作者：Earl Miller

译者：刘进龙/汪皓

Here’s Why You Shouldn’t Multitask, According to a MIT Neuroscientist

This article is part of Tools of the Trade, a weekly series in which a variety of experts share actionable tips for achieving fast and effective results on everything from forming good habits to raising money.

This week Earl Miller, a professor of neuroscience at The Picower Institute for Learning and Memory at MIT, breaks down why you shouldn’t multitask.

Here’s practical advice from a neuroscientist: Don’t try to multitask. It ruins productivity, causes mistakes, and impedes creative thought. Many of you are probably thinking, “but I’m good at it!” Sadly, that’s an illusion. As humans, we have a very limited capacity for simultaneous thought — we can only hold a little bit of information in the mind at any single moment.

Our brains, however, delude us into thinking we can do more. To understand how this happens, it helps to think about how we physically see the world. Barring visual impairments, we perceive our surroundings via a video camera-like, wide-angle lens. Or at least that’s how it seems. In reality, our eyes are constantly darting around, 3-4 times per second, taking in our surroundings in snippets. The end looks like one image, but that’s just because our brains paper these individual pieces together to create a complete picture.

The same is true for multitasking. When we toggle between tasks, the process often feels seamless — but in reality, it requires a series of small shifts. Say you stop writing a pitch for a client in order to check an incoming email — when you finally return to the pitch, your brain has to expend valuable mental energy refocusing on the task, backtracking, and fixing errors. Not only does this waste time, it decreases your ability to be creative. Innovative thinking, after all, comes from extended concentration, i.e. the ability to follow an idea of thought down a network of new paths. When you try to multitask, you typically don’t get far enough down any road to stumble upon something original because you’re constantly switching and backtracking.

If you’re thinking “this probably just applies to other people” — wrong. In fact, studies show that people who think they are good at multitasking generally have a lower capacity for simultaneous thought. It’s a rationalization fest. Frequent offenders are bad at ignoring distractions, but instead of trying to improve their ability to focus, they convince themselves that multitasking increases productivity.

Maybe you’re wondering, “if multitasking is bad, why do we have the urge to do it?” The answer likely has to do with how our brains evolved. Back in prehistoric days, any new piece of information might be critical — a rustling in the bushes, for example, could mean a tiger was about to leap. Thus, it was adaptive for our brains to seek out and pay attention to new information. Unfortunately, what was once an evolutionary advantage has become a distraction. In today’s modern society where our lives are rarely on the line, the ceaseless onslaught of information has the potential to cripple us. Our brains aren’t equipped to handle the sensory overload.

Here’s what to do about it.

Start by blocking out a period of time to focus. Eliminate as many distractions as possible: Put away your phone, turn off extra computer screens, shut down your email if you have to. Don’t try to mono-task by willpower alone; it’s too hard to fight the thirst for new information. Instead, prevent the urge by removing temptation. If you find yourself unable to concentrate, try taking a short break and move around. Increasing blood flow to your brain can help restore focus.

One final word of advice: Please, please put away your phone when you drive. Mute it, put it out of reach. (Hands-free headsets don’t help; it’s the cognitive demands of conversation that causes the distraction.) Being able to pay attention to your driving while on the phone is another delusion — the work of David Stayer and colleagues shows that it causes drivers to miss as much as half of the things in front of them. Multitasking while driving is just plain dangerous.