(单词翻译:单击)
Parents were once warned against raising children to speak more than one language.
父母们都听到过这样的警告，不要让孩子说一种以上的语言。
It's bad for kid's cognitive development, they were told, and will result in bad grades and a lower IQ!
说这样会对孩子的认知发展有害，导致成绩差、智商较低！
And that ridiculous claim is still sometimes repeated, especially here in the United States.
这种荒谬的说法有时还在不断重复，尤其是在美国。
But times have mostly changed.
但时代不同了。
Now, if you believe the headlines, being bilingual makes you smarter and more creative.
现在，头条新闻会说双语让你更聪明、更具创造力。
And those headlines don't come from nowhere.
这些头条新闻并非空穴来风。
There is research which suggests that bilingualism provides some specific cognitive advantages.
有研究表明，双语能够提供一些特定的认知优势。
And you can hardly blame the press for covering these studies, because it's such an appealing idea: teach your child French and you get a better child!
也不能责怪媒体报道这些研究，因为这是一个很有吸引力的想法：教孩子学法语，你的孩子会变得更优秀！
More creativity, multitasking, and academic performance in other subjects all for free!
更具创造性、能同时处理多项事情、其他学科成绩优秀，所有这些都是免费的！
But if that sounds too good to be true, that's because it is.
但如果这听起来太好了，不像是真的，那是因为它就是真的。
You see, there are also studies that don't find an advantage.
还有一些研究没有发现学习多种语言的优势。
Those don't get the same excited coverage.
这些研究获得同样令人兴奋的报道。
In this case, though, the media aren't really the ones to blame.
不过，在这种情况下，媒体并不是真正的罪魁祸首。
When it comes to the effects of bilingualism on the brain, there's confusion and bias on the scientific side, too.
谈到双语对大脑的影响时，从科学角度讲也存在着困惑和偏见。
And it all goes to show just how hard it can be to understand what really goes on in our heads.
这一切都表明，要理解我们头脑中到底发生了什么是多么困难。
Learning another language definitely has benefits that's no one can argue against — like, for example, you'll know another language!
学习另一种语言肯定会让人受益，这个没有人会反驳——例如，你会了解另一种语言！
And it even makes sense that it could benefit your brain in other ways.
它甚至可以用其他方式让你的大脑获益。
The main benefit is thought to be to executive functions — the processes that control complex cognitive tasks like attention, problem solving, planning, and so on.
主要的好处被认为是执行功能，控制复杂认知任务的过程，如注意力、问题解决、计划等。
And that hypothesis isn't unreasonable.
这种假设并非不合理。
It's thought that these processes are kind of like muscles — the more you use them, the better you get at them.
人们认为这些过程有点像肌肉，用得越多越灵活。
And research has found that all sorts of cognitively challenging activities improve executive functions.
研究发现，各种具有认知挑战性的活动都能提高执行功能。
Like, playing video games can make you better at assessing risks and placing bets.
比如，玩电游可以让你更好地评估风险和下注。
And music training can improve your ability to focus on specific tasks.
音乐训练可以提高你专注于特定任务的能力。
Since juggling two or more languages in your brain is cognitively challenging in a lot of ways, it could have similar positive effects.
由于在大脑中使用两种或更多语言，在很多方面都具有认知上的挑战性，因此它也可能有类似的积极作用。
Constantly switching between vocabularies could help you be a better multitasker, for example, if it made you generally better at quickly shifting your brain from one thing to another.
例如，经常在词汇表之间切换可以帮助你成为一个更好的多任务处理者，因为它能让你更好地、快速地将大脑从一个事物转移到另一个事物。
But more than one analysis of the research has found that the evidence for such benefits is weak and inconsistent.
但有关此项研究的多项分析发现，这种益处的证据微弱，而且并不一致。
For example, a 2015 review in the journal Cortex concluded that over 80% of the tests conducted over four years of studies don't show a bilingual advantage.
例如，《Cortex》期刊在2015年的一篇综述文章中得出结论，在过去四年的研究中，超过80%的测试没有显示出双语优势。
Those that did had serious problems with their methodology — like, they had small sample sizes or inadequate controls.
那些研究的方法确实存在严重问题——比如，样本量小或进行的控制不足。
But there's a more foundational problem with the published research on bilingualism: it doesn't tell the whole story.
但是，发表的双语研究有一个更为根本性的问题：没有讲述完整的故事。
This was pointed out by a study published in 2014 in the journal Psychological Science.
2014年发表在《心理科学》期刊上的一项研究指出了这一点。
The researchers started by looking at the research presented at conferences from 1999 to 2013.
研究人员首先研究了1999年至2013年会议上展示的各项研究。
Roughly half these presentations found some advantage for bilingualism and half didn't.
其中大约半数研究发现双语有好处，一半研究发现没有好处。
Then they looked at which ended up getting published in journals, and found something striking: 68% of the positive studies got published, while only 29% of the negative ones did.
然后他们研究了哪些论文最终发表在期刊上，得到的结果令人吃惊：68%的正面研究得以发表，而只有29%的负面研究得以发表。
The published and unpublished studies didn't consistently differ based on sample size, experimental tests used, or statistical power.
已发表和未发表的研究在样本量、使用的实验测试或统计功效方面并非始终存在差异。
A study simply had a better chance of getting published if it supported the idea that bilingualism gives people a cognitive boost, and a worse chance of getting published if it showed the opposite, regardless of the quality of the work.
如果一项研究支持双语能提高人们认知能力的观点，那么它被发表的几率就更大；如果显示出相反的观点，那么不管研究质量如何，文章发表的几率都更小。
This is a phenomenon known as publication bias, and it's not unique to this situation, it's not unique to psychology.
这是现象称为出版偏见，这种情况并不少见，也不只存在于心理学研究中。
It's a pervasive issue scientists from all fields are grappling with because it can undermine the research that is published.
这是一个普遍存在的问题，来自各个领域的科学家正在努力解决，因为它会破坏已发表的研究结果。
For example, a 2018 meta-analysis of over 150 studies on adults did find bilinguals were slightly better at some executive functions.
例如，2018年，对超过150项成人研究进行的元分析发现，双语者在某些执行功能方面略胜一筹。
But those advantages disappeared when the researchers corrected for publication bias.
但当研究人员纠正出版偏差时，这些优势就消失了。
Now, it's important to point out that none of this amounts to proof that there are no cognitive advantages to bilingualism.
现在，重要的是要指出，这些都不足以证明双语没有认知优势。
But it's clearly going to take a lot more work to figure out if there are, and if so, whether any of them are unique — or if studying Japanese is basically the same as playing Minecraft, from your brain's perspective.
但显然需要进行更多的研究，弄清楚是否存在优势，如果有的话，是否某种优势具有独特性，或是从大脑的角度来看，是否学习日语与玩Minecraft手游相似。
This also applies to another often-repeated claim about bilingualism: that it can delay the onset of dementia.
这也适用于另一个反复提到的关于双语的说法：它可以延缓痴呆症的发作。
Again, the idea seems reasonable at first glance, as other complex cognitive activities do seem to prevent or delay dementia.
这个想法乍一看似乎也很合理，因为其他复杂的认知活动似乎确实能预防或延缓痴呆症。
But, a 2015 review of the literature found that the effects of bilingualism on dementia are very inconsistent. And that's not all.
但2015年的文献综述发现，双语对痴呆症的影响非常不一致。而这还不是全部内容。
There were some suspicious patterns in the research methods.
研究方法中存在一些令人生疑的模式。
You see, prospective studies — the ones that enroll people before they show symptoms and then test them as they age — tended not to show an effect of bilingualism.
前瞻性研究，即在人们出现症状之前对他们进行招募，然后随年龄增长进行测试的研究，往往不会显现双语的影响。
Positive results were mostly found in retrospective studies, which look at people after they've been diagnosed.
在回顾性研究中发现了正面结果，这些研究是在人们确诊后进行评估。
Subjects in that kind of study may not be representative of the whole population, and it's harder to pick good controls.
这类研究中的受试者可能无法代表整个人群，选择良好的对照标准也更加困难。
That all suggests that the researchers might have been seeing what they wanted in the data, and having their judgment biased by their expectations.
这些都表明，研究人员可能已经在数据中看到了他们想要的东西，他们的判断受到了期望的影响。
So not only do studies on bilingualism have issues with publication bias, there may be straight-up bias in many of them.
因此，对双语机制的研究不仅存在发表偏倚的问题，而且许多研究可能存在直接的偏见。
And this all means we really don't know if learning a second language can give you some kind of subtle cognitive advantage or keep your brain healthy as you age.
这一切都意味着，我们真的不知道学习第二语言是否可以带来一些微妙的认知优势，或者随着年龄的增长使大脑保持健康。
Still, we can say that learning a language does make you smarter.
不过，我们可以说学习一门语言确实让你更聪明。
No matter what, you'll know something you didn't know before.
不管怎么说，你都会了解以前不知道的事情。
So in that sense, of course it makes you smarter.
所以从这个意义上讲，它当然会让你更聪明。
And it's not going to hurt you, like they thought in the old days.
不会像人们过去认为的那样，多学外语会对你造成伤害。
Not only that, with your new fluency, you can experience whole new bodies of literature and arts, travel to interesting places, and talk to more people.
不仅如此，流利掌握了新语言，你还可以体验全新的文学艺术，到有趣的地方旅行，与更多人交谈。
So yeah, being able to speak multiple languages has lots of benefits, even if it's not boosting your brain indirectly.
能够说多种语言有很多好处，即使它没有间接地增强脑功能。
If the idea of traveling the world and experiencing new things sounds awesome to you, I have a feeling you'll like the videos offered by Curiosity Stream.
如果你觉得周游世界、体验新事物听起来超棒，我觉得你会喜欢Curiosity Stream提供的视频。
CuriosityStream is a subscription streaming service that offers over 2,400 documentaries and nonfiction titles from some of the world's best filmmakers, including exclusive originals.
CuriosityStream是一个订阅流媒体服务，提供由世界上一些最好的电影制作者摄制的2400多部纪录片，其中包括独家原创作品。
For example, if languages are your jam, you might like their original documentary The History of English.
比如，如果学习语言是你的痛点，你可能会喜欢他们的原创纪录片《英语史》。
It takes you on a trip through time and around the world to understand how this particular language came to be a "linguistic superpower".
它能带你穿越时空，环游世界，了解英语这种特殊语言是如何成为“超级语言”的。
And they have videos on nature, history, technology, and society and lifestyle, too.
他们也有关于自然、历史、技术、社会和生活方式的视频。
For as little as $2.99 a month, you can get access to all of them.
每月只需支付2.99美元，就能访问所有视频。
And if that's not enough for you, as a SciShow Psych viewer, you can get your first 31 days completely free!
如果这还不够吸引你的话，心理科学秀的观众可以在前31天免费观看！
All you have to do is sign up at curiositystream.com/Psych and use the promo code 'psych', that's P-S-Y-C-H during the sign-up process.
只需在curiositystream.com/Psych注册并使用促销代码psych，就是在注册过程中输入P-S-Y-C-H。
