Even though only piano notes are being played,

即使只有鋼琴在演奏

if you know the song, you'll start to hear the lead singer's voice and the words being sung.

如果你知道這首歌，你會開始聽見主唱的歌聲以及他所唱出的歌詞

I swear, what you're hearing is 100% digital piano simply matched to the frequency of the original song and not mixed with real vocals.

我發誓，你現在聽的是百分之百的電子琴聲，單純地將琴聲的音頻對應上原曲，並不混合任何真實歌聲

And yet, you can hear the words.

即使如此，你仍可聽見歌詞

This speaking piano shows a similar phenomenon.

這台會說話的鋼琴顯示出相同的現象

It's hard to make out what it's saying, but as soon as words are on screen, you begin to hear it talking.

很難聽出它在說什麼，但是當文字出現在螢幕上，你便開始聽見它在說話

Hearing is all about perception, after a soundwave hits your ear, it's transformed into signals for your brain.

聽覺與感知有關， 聲波傳至你的耳朵之後，就會轉化為信號傳遞給你的大腦

But your brain gets so many external signals that it can't process it all at once and so it uses context to craft what you're hearing.

但是你的大腦得到這麼多的外在訊息，無法一次同時處理，所以它藉由前後段的音樂來得出你在聽什麼

You hear the lyrics because the brain uses the information it already has to understand the world around you.

你聽見歌詞是因為大腦使用它已經掌握的訊息來了解你週遭的世界

which is why if you've never heard the song, it will sound like nonsense.

這就是為何如果你從未聽過這首歌，這些聲音會聽起來毫無意義

But, even without words, we sometimes hear things that aren't there.

但即使沒有歌詞，有時候我們仍聽見不存在的東西

Take this jumping transmission tower, for example.

以這個跳躍中的輸電塔為例

Around 20% of people will actually hear a thud each time it lands in a fenomenun known as visually evoked auditory response.

大約 20% 的人在它落地時，會確實地聽見砰的撞擊聲，這就是所謂視覺所引發聽覺反應的現象

Do you hear it?

你有聽到嗎？

It's a type of synesthesia which is when the senses like hearing and sight get crossed in the brain.

這是一種聯覺，即感官如聽覺與視覺在腦中交叉所產生的

Expectation is also playing a role here

期望也會在這方面造成影響

A 2006 study scanned the brains of participants who were told they'd eventually hear a sound

一個在 2006 年的研究掃描了受試者的大腦，他們被告知將會聽見一個聲音

as they were listening to the silence and expecting to hear something, the auditory cortex was activated in the same way as when you were actually listening to sound.

當他們在寂靜中聆聽並期望聽到一些東西時，聽覺皮質的活化和你真正聽聲音的時候是一樣的

So, do you hear it now?

所以，你現在聽到了嗎？

Our brains are pretty good at filling in the gaps, like in this audio clip.

我們的大腦很擅長於填補空缺的訊息，像是這個錄音檔

The state governors met with their respective legislatures convening in the capital city.

國家首長召集他們各自的立法機關於首都面會

But, now, listen to it with the cough removed.

但，現在，聽聽看咳嗽聲被移除的

The state governors met with their respective leg_latures convening in the capital city.

國家首長召集他們各自的立＿機關於首都面會

There's literally a full syllable missing.

確實有一個音節不見了

But with the cough, people tend to hear the entire word.

但有咳嗽聲時，大家通常能聽見一個完整的字

The state governors met with their respective legislatures convening in the capital city.

國家首長召集他們各自的立法機關於首都面會

This illusion is known as "temporal induction".

這種幻覺稱之為「時間歸納法」

Your brain fills in information to make sense of the world.

你的腦填補上訊息以理解這個世界

Now, listen to this rhythm.

現在，聽聽這段旋律

Sounds like it's getting faster, doesn't it?

聽起來越來越快，不是嗎？

The thing is, it will seemingly get faster forever if I let it continue to play.

事實上，如果我繼續播，它感覺只會變得越來越快

This is known as the "Risset rhythm" in which a beat starts relatively slow and starts to speed up,

這就是所謂的「Risset 節奏」，旋律的拍子會由慢變得越來越快

but, as it gets faster, beat 2 starts at exactly half the speed and they increase in speed together.

但當它越來越快，第二段拍子以一半的速度進來，接著他們一起加快速度

Eventually, the faster one fades out as the slower one fades in, and the loop continues.

最終，較快的一個淡出，較慢的一個淡入，這個循環會持續進行。

But, your brain can't pick up the subtlety and, as a result, it sounds like it's speeding up forever.

但你的大腦無法認出這細微變化因此，這聽起來就像是無限地加速下去

Love learning about amazing and interesting things in the world?

樂於學習這世界上驚奇又有趣的事嗎？

We actually just started a brand new podcast called "Sidenote" where we explore the things that are stumping us or making us curious in life

事實上我們推出了一個全新的廣播節目叫「Sidenote」我們會探究那些生活中令人困惑或令人好奇的事

and then insert all the mind-blowing science behind it.

並納入事物背後各種超乎想像的科學

We'd love for you to check it out at iTunes or whichever podcast app you use.

我們誠摯邀請你上 iTunes 或是任何廣播應用程式去查看

Your support means a ton to us as we slowly journey into exploring more science in a new media.

你的支持對我們來說意義重大，因我們正在新媒體上展開探索科學的旅程

Again, it's called "Sidenote" and it's brand new so we're excited to know what you think.

讓我再說一次，它叫做「Sidenote」，這是全新的嘗試，而我們很期待收到你的回饋

We'll leave some links below and subscribe for more weekly science videos every Thursday.

我們將連結放在下方，訂閱才能在每週四收到更多科學短片