(单词翻译:单击)
Maybe you're driving home from work and traffic's a little heavy,
也许你下班正开车回家，路上有点堵车，
so you decide to call your mom.
你决定给妈妈打个电话。
Or maybe you're watching SciShow while doing some calculus homework.
或者你在看科学秀的同时做微积分作业。
And it seems like both tasks are going well enough, since you might consider yourself good at multitasking.
这两项任务似乎都进行得很顺利，你可能认为自己擅长多任务处理。
Sound familiar?
有没有很熟悉？
Sure, you might think you're doing well.
当然，也许你会认为你做得很好。
But as it turns out, you're just not noticing your mistakes.
但事实证明，你只是没有注意到自己的错误。
According to lots of psychology studies – from researchers ranging from the University of Michigan to Stanford –
根据大量的心理学研究——从密歇根大学到斯坦福大学的研究人员——
when you think you're multitasking, you aren't actually doing two tasks at the same time.
你以为你在处理多项任务，实际上你并没有同时做两件事。
Instead, you're switching between them quickly so that you don't even notice.
快速地在两件事之间来回切换让你注意不到。
And, in the process of switching, you're taking longer and making more mistakes on both things than if you were doing one at a time.
而且，在切换的过程中，比起一次只做一件事，一次做两件事花费的时间和犯的错误要更多。
So, why can't we multitask?
那么，为什么我们不能同时处理多项任务呢?
Your brain just isn't designed to do two things at once, and that has to do with your brain's executive control processes.
大脑并没有同时做两件事的设计，这与大脑的执行控制过程有关。
These processes take place with help from your prefrontal cortex, the brain region you're using to concentrate right now.
执行控制过程在前额皮质的助力下进行，前额皮质是用来集中注意力的大脑区域。
And they're responsible for most of your control and decision-making.
该区域负责人大部分的控制和决策。
And you might be thinking "Hank, how are you so sure I'm concentrating right now?"
你可能会想“汉克，你怎么能确定我现在很专注?"
It's because you are hearing what I'm saying!
那是因为你在听我说话!
And if you are not, you are not concentrating. So I know!
如果你没有听到我说的话，说明你没有集中注意力。所以我知道!
Psychologists think executive control processes have two distinct phases: goal shifting and rule activation.
心理学家认为，执行控制过程有两个不同的阶段：目标转移和规则激活。
In the goal shifting phase, your brain concentrates on doing Task A instead of Task B.
在目标转移阶段，大脑专注于做任务A而非任务B。
And in the rule activation phase, your brain focuses on turning off the rules it needs for the first task and turning on the rules for the next one.
在规则激活阶段，大脑专注于关闭第一个任务需要的规则，并调取下一个任务的规则。
So, in the example, one study asked participants to multitask by solving simple math problems while also classifying different shapes.
因此，例如，一项研究要求参与者在解决简单的数学问题的同时分类不同的形状，进行多任务操作。
So first, your brain might work on the math problems instead of sorting shapes.
首先，大脑可能会处理数学问题而非分类形状。
It would focus on the rules for how to do math – like order of operations or how to add numbers –
大脑将专注于数学题的规则——比如操作的顺序或如何添加数字——
instead of the rules for choosing circles or squares.
而不是选择圆或正方形的规则。
And when you switch tasks, first your brain would have to shift goals from math to shapes, then it would have to recall the rules to classify shapes.
当你切换任务时，首先大脑必须将目标从数学转移到形状，然后大脑必须回忆规则来对形状进行分类。
Going through these stages helps your brain shift between tasks without you realizing it – but it also takes time, even if it's just a few tenths of a second.
这些过程可以帮助你的大脑在不同的任务之间转换（你并没有意识到）——但这也需要时间，即使只有零点几秒。
Now, that doesn't seem like very long, but those delays will add up over time.
现在你会觉得时间不长，但是随着时间的推移，停留时间会加长。
The same study also showed that multitasking with more complicated or unfamiliar tasks caused the delays to get longer with even more mistakes.
同样的研究还表明，处理更复杂或不熟悉的任务会导致停留时间更长，错误更多。
Those short delays can have real-world implications–
这些短暂停留可能会对现实世界产生影响
like, a tenth-second delay while switching between answering your phone and paying attention while driving is about all it takes to cause an accident.
比如，在接听电话和集中注意力开车之间切换停留的十秒钟，就足以导致事故的发生。
Besides making you less productive, there's a chance that multitasking might affect, or be affected by, the structure of your brain.
除了降低工作效率，多任务处理也有可能影响大脑结构或被大脑结构所影响。
One 2014, peer-reviewed study from the Public Library of Science looked at the relationship between how often people multitasked and their brain structure.
2014年，美国公共科学图书馆进行了一项同行评议研究，研究了人们多任务处理的频率与其大脑结构之间的关系。
The participants who multitasked the most had less gray matter, the brain tissue that's mostly neurons, in a region called the anterior cingulate cortex,
一次处理最多任务的参与者大脑灰质较少，灰质主要为前扣带皮层的神经元脑组织，
which is located near the prefrontal cortex and is involved in decision-making and impulse control.
它位于前额皮质附近，负责决策和冲动控制。
But since it was a correlational study, the researchers were just observing people and weren't actually manipulating variables.
但由于这是一次相关性研究，研究人员只是观察，并没有真正操纵变量。
In other words, they couldn't determine if more multitasking causes the tissue loss or if less neurons in that region just happens to be related to the behavior,
换句话说，他们无法确定多任务处理是否会导致组织受损，或者该区域的神经元数量减少是否恰好与行为有关，
so more research needs to be done before we can draw any conclusions.
所以在我们得出任何结论之前还需要进行更多的研究。
So, the research seems to suggest that we stop multitasking and focus on one thing at a time.
因此，研究似乎表明，我们需要停止一心多用，一次只专注于一件事。
But what if it isn't that easy?
但倘若不那么容易办到呢?
Whenever you complete a small task – like sending out a funny tweet while working on a big project –
当你完成一个小任务——比如在处理一个大项目的时候发一条有趣的推特——
your brain releases the hormone dopamine, which makes you feel a small sense of reward and accomplishment.
大脑会释放多巴胺，多巴胺会让人感到小小的奖励和成就感。
Since that's such a great feeling, it encourages you to keep multitasking.
这种感觉很棒，会鼓励你继续多任务处理。
Even though you might be doing each small task inefficiently or with more errors, your brain keeps releasing dopamine, so the multitasking continues.
即使你在做每一件小事的时候效率低下或者出错更多，你的大脑还是会不断释放多巴胺，所以多任务处理还在继续。
It's kind like a vicious cycle.
这有点像恶性循环。
On top of that, your prefrontal cortex is easily distracted and excited by new things, like kittens and memes, and whole internets worth of those things,
最重要的是，你的前额皮质很容易受到干扰和对新事物，比如小猫和表情包以及整个互联网吸引你的事物，产生兴奋，
so it makes multitasking even more tempting.
因此，多任务处理更加吸引人。
But, for the sake of your job or your GPA, maybe finish that project you're working on,Then come catch up on SciShow!
但是，为了你的工作或者你的平均成绩，任务完成之后再来看科学秀吧!
Thanks for watching this episode of SciShow Psych!
感谢收看本期心理科学秀！
And special thanks to our patrons on Patreon for helping us get this channel off the ground!
特别感谢Patreon对本节目的支持！
If you'd like to help us make more episodes like this, check out patreon.com/scishow.
如果你想帮助我们制作更多这样的剧集，请访问patreon.com/scishow。
And if you wanna be the first to see new episodes here, you can go to youtube.com/scishowpsych and subscribe!
如果你想第一个看到新剧集，你可以登陆订阅youtube.com/scishowpsych!
