Turns out, we couldn't have been more wrong.

事實證明，我們錯得離譜。

Learning new languages is an exercise of the mind.

學習新語言是一種思維鍛鍊。

It's the mental equivalent of going to a gym every day.

這就相當於每天去健身房鍛鍊。

In the bilingual brain, all our languages are active, all at the same time.

在雙語大腦中，我們所有的語言都是活躍的，同時進行。

The continual effort of suppressing a language when speaking another, along with the mental challenge that comes with regularly switching between languages, exercises our brain.

在說另一種語言時不斷抑制一種語言，以及定期切換語言所帶來的精神挑戰，都會鍛鍊我們的大腦。

It improves our concentration, problem solving, memory, and in turn our creativity.

它能提高我們的注意力、解決問題的能力和記憶力，進而激發我們的創造力。

It's now widely accepted that there are huge benefits to being bilingual.

現在人們普遍認為雙語有巨大的好處。

A key breakthrough came back in 2007 in Toronto, when Ellen Bialystok and her team made a discovery that shook the scientific community - and has massive real-world implications.

2007 年，多倫多出現了一項重大突破，當時 Ellen Bialystok 和她的團隊做出了一項震驚科學界的發現，並對現實世界產生了巨大影響。

It was the first study which suggested that bilingual people - people who speak more than one language - develop dementia four to four-and-a-half years later than those who don't.

這是第一項研究表明，雙語者（會說多種語言的人）比不會說兩種語言的人晚四到四年半患癡呆症。

It was a powerful confirmation of the idea of cognitive reserve.

這有力地證實了認知儲備的觀點。

Now, what is cognitive reserve?

什麼是認知儲備？

Cognitive reserve is the idea that people develop a reserve of thinking abilities, and this protects them against losses that can occur through ageing and disease.

認知儲備是指人們發展思考能力儲備，這可以保護他們免受因老化和疾病而造成的損失。

As well as delaying the onset of dementia, bilingual people have been shown to recover significantly better after a stroke.

除了延緩失智症的發作之外，雙語者在中風後的恢復效果也明顯較好。

Learning anything new helps build cognitive reserve.

學習任何新知識都有助於建立認知儲備。

But there's something special about language.

但語言有其特殊性。

Language is particularly broad and complex.

語言尤其廣泛而複雜。

It affects ideas and concepts, perception, different sounds.

它影響思想和概念、感知和不同的聲音。

The more complex a certain skill is, the more likely it is to have a positive effect on cognitive reserve.

某種技能越複雜，就越有可能對認知儲備有積極影響。

So when is the best time to learn a new language?

那麼，什麼時候是學習一門新語言的最佳時機呢？

Well, here's part of the answer.

答案就在這裡。

The brain is a complex set of neural networks.

大腦是一組複雜的神經網絡。

When you're learning a new language as a child, you're building new networks.

小時候學習一門新語言時、建立新的網絡。

But when you learn a language later in life, you have to modify the existing networks and make more connections.

但當你在晚年學習一門語言時，你必須修改現有網絡，並建立更多聯繫。

Because learning languages later in life can be more challenging, the benefits can also be greater.

因為晚年學習語言可能更具挑戰性，效益也會更大。

But a 2023 study at Great Ormond Street suggests this is just part of the story.

但大奧蒙德街 2023 年的一項研究表明這只是故事的一部分。

So we invited three groups of children that were aged 8 to 10.

所以我們邀請了三組8到10歲的孩子。

We had a group of children who were monolinguals.

我們有一群只會說單語的孩子。

A group of children who had early exposure to Greek and English from birth - they were our early bilinguals.

一組從出生起就接觸希臘文和英文的孩子──他們是我們早期的雙語者。

And finally, we had a group who had been exposed to English between the age of two and five, and they were our later bilinguals.

最後，我們有一組在兩歲到五歲之間接觸過英語的人，他們就是我們後來的雙語者。

So what we did that no-one had done before, is that we asked the children to lie in the scanner while doing nothing - and just stare at a cross.

所以我們做了一件以前沒有人做過的事情，就是讓孩子們躺在掃描器裡什麼都不做——只是盯著一個十字架。

And during this, we measured their brain activity.

在此期間，我們測量了他們的大腦活動。

What we found that was really exciting for us is that our early bilingual group had the strongest connectivity in the network at rest.

我們發現令人興奮的是，我們早期的雙語組在休息時的網路中具有最強的連結性。

And these group of regions are regions that light up when we're doing nothing and just mind-wandering.

當我們無所事事、分心時，這些區域就會發光。

A little bit like if you're going to the gym every day, your muscles might look bigger at rest.

有點像如果你每天都去健身房，你的肌肉在休息時可能看起來更大。

Similarly, your brain might be better connected at rest, because you are learning a language early.

同樣，你的大腦在休息時可能會連接得更好，因為你很早就開始學習語言了。

And this is something no-one had found before.

這在以前是沒有人發現過的。

And there's more.

還有更多。

One lesser-known behavioural effect of bilingualism in both children and adults is the ability to see the other people's perspective, or to understand that it is possible to have different points of view.

雙語對兒童和成人的一種鮮為人知的行為影響是能夠看到他人的觀點，或理解可能有不同的觀點。

Recent studies have also found that people tend to react more emotionally in their first language, and more rationally, in a more abstract way, in their second.

最近的研究也發現，人們在使用第一語言時往往會更加情緒化，而在使用第二語言時會更加理性、更加抽象。

And the way it is usually explained is that the first language is the one which we use to speak with family, with friends - in informal settings.

通常的解釋是，第一語言是我們在非正式場合與家人、朋友交談的語言。

The second language is usually learned at school, at the university, at work.

第二語言通常是在學校、大學或工作中學習的。

Scientists are discovering new upsides to being bilingual all the time.

科學家一直在發現雙語的新好處。

And it's not just our brains that benefit.

受益的不僅僅是我們的大腦。

Learning new languages, and speaking more than one language, is very important - not only for individuals, but also for societies.

學習新語言和說不只一種語言非常重要——不僅對個人，對社會也是如此。

Learning new languages can open doors to new cultural experiences, life opportunities.

學習新語言可以打開大門新的文化體驗和生活機會。

Different people, different communities, and different ways of seeing the world.

不同的人，不同的社群，以及看待世界的不同方式。

And with that, we'll say a final...

最後，我們要說...

Bye!

再見！