耳朵是如何工作的？

ABC 收听。

ABC listen.

一，二。

One, two.

一，二，三，四。

One, two, three, four.

哦，嘿，你好。

Oh, hey there.

我叫 Nij，今天在《想象一下》节目里，我要在我的架子鼓上尽情敲打。

My name is Nij, and today on Imagine This, I'm rocking out on my drum kit.

我要拉小提琴。

I'm going to play the violin.

我要打敲击棒。

I'm going to play the tapping sticks.

我要弹吉他和打鼓。

I'm going to play guitars and drums.

太吵了，Nij。

It's too loud, Nij.

什么？

What?

摇滚声太大，我听不清你说话。

I can't hear you over all the rocking.

太吵了，Nij。

Too loud, Nij.

啊。

Ah.

抱歉。

Sorry.

我想确实挺吵的。

I guess it is pretty noisy.

我喜欢做音乐。

I love making music.

你可以发出轻柔的声音，也可以发出响亮的声音，有低音也有高音。

You can make soft sounds and loud sounds, low sounds and high sounds.

等等，什么？

Wait, what?

它是怎么发出声音的？

How does it make the sound?

琴弦。

The strings.

触摸琴弦。

Touch the string.

然后它们就发出声音。

And they make sound.

也许声音会弹进我们的耳朵里。

Maybe the sound bounces into our ears.

带着一种特殊的声波冲击？

With a special sound blast?

啊。

Ah.

你们中有几个人对这个问题很好奇。

A few of you have been curious about that.

我叫汤姆。

Name is Tom.

我四岁了。

I am four years old.

我的问题是，我们的耳朵是怎么工作的？

My question is, how do our ears work?

嗨，我是哈里，我四岁了。

Hi, I'm Harry, and I'm four years old.

我想知道声音是怎么产生的，又是怎么传到我们耳朵里的。

And I would like to know how are sound made and how does it get to our ears.

嗨，尼吉。

Hi, Nij.

我叫麦肯齐，今年四岁，我想知道耳朵是怎么工作的。

My name is Mackenzie, and I'm four years old, and I'd like to know how the ears work.

有什么想法吗？

Any ideas?

它会传播。

It travels.

时间会传播。

Time travels.

我们身体的感官会向大脑发送信号，告诉我们这里有声音。

The senses of our body put a signal into our brain to tell us that there's noise here.

它从很高的悬崖上掉进我们的耳朵里。

It falls into our ear from a very high cliff.

我真的不知道，但我认识一个知道的人。

I really don't know, but I know someone who does.

维吉·伊斯瓦博士。

Dr Viji Easwar.

她是一位科学家，也是一位听力学家。

She's a scientist and an audiologist.

听力学家是一种医生，专门研究耳朵以及耳朵是如何听到声音的。

That's a type of doctor who knows all about ears and how they hear sounds.

她现在来了。

That's her now.

你好，伊斯瓦医生。

Hello, Dr Easwar.

你好，维吉医生。

Hi, Dr Viji.

你好，维吉医生。

Hi, Dr Viji.

你好。

Hi.

准备好参加乐队排练了吗？

Ready for band practice?

我把小提琴带来了。

I've brought my violin.

对，不过先别急，你能帮我们解答一些关于声音和听觉的问题吗？

Yeah, but first, can you help us with some of our questions about sound and hearing?

当然可以。

Of course.

有什么我可以帮你们的？

What can I help you with?

声音是怎么进入我们耳朵的？

How does sound go inside our ears?

我们又是怎么听到它的？

And how do we hear it?

它是飞过房间钻进我们耳朵里的吗？

Is this flying across the room into our ear holes?

差不多吧。

Kind of.

空气并不是空的。

Air isn't empty.

里面充满了微小的、看不见的颗粒。

It's full of tiny, invisible particles.

正是这些颗粒在传递声音。

They are the ones carrying the sound.

像风一样吗？

Like wind?

空气本身并没有怎么流动。

The air isn't moving much.

这些颗粒有点像一排朋友，互相推挤。

Those particles are a bit like a line of friends all nudging each other.

没有人离开自己的位置，但推挤会沿着整排传下去。

No one moves from their spot, but the nudge goes all the way down the line.

啊。

Ah.

所以当你发出声音时，它会让空气粒子互相碰撞，直到声音传到你的耳朵里。

So when you make a sound, it makes the air particles bang into each other until it gets into your ears.

没错。

That's right.

声音就是能量在空气中传播。

The sound is energy moving through the air.

我们称之为声波。

We call it a sound wave.

我不明白。

I don't get it.

这有点难懂。

It's a little tricky.

声波是看不见的，但你可以看到耳朵里面发生了什么。

Sound waves are invisible, but you can see what's happening inside the ear.

我们为什么不把自己想象成声波呢？

Why don't we imagine ourselves as sound waves?

这样我们就能走完整个旅程了。

That way, we can follow the whole journey.

我要当玻璃碎裂的声音。

I'm going to be glass breaking.

哇。

Whoa.

我要当恐龙。

I'm going to be a dinosaur.

哦，这个不错。

Ooh, nice one.

雷声。

Thunder.

我要当狗在草地上抓挠的声音。

I'm going to be a dog scratching on the grass.

哦，这个我不太清楚。

Oh, I don't know about that one.

那Nish呢？

What about Nish?

哦，我会是什么？

Ooh, what would I be?

指甲刮黑板的声音。

Fingernails on a chalkboard.

不，那声音不好听。

No, that's a bad sound.

我会是鼓点。

I'll be a drum beat.

我会是雨滴。

I'm going to be a raindrop.

开始吧。

Here we go.

哇哦。

Woo-hoo.

感觉就像在飞一样。

It's like we're flying.

更像是冲浪。

More like surfing.

其实我们是声波。

The truth is we are sound waves.

对。

Yes.

声音通过空气传播，是看不见的波，靠空气粒子一个接一个地推拉传递。

Sound travels as invisible waves through the air by the particles of air pushing and pulling on each other, one after another.

冲浪开始啦。

Surf's up.

耶！

Yew.

如果附近有人听到，声波会被耳廓收集起来。

If someone's nearby to hear it, the sound waves get funneled by the pinna.

什么是耳廓？

What's a pinna?

就是你耳朵外面的部分。

The outside part of your ear.

那些皮肤和软骨的褶皱都是有原因的。

All those folds of skin and cartilage are there for a reason.

是为了捕捉声波吗？

To catch sound waves?

没错。

That's right.

哇，我们进到耳骨的管道里了。

Whoa, we're in the barrel of the ear bones.

太酷了。

Sick.

真珍贵。

Precious.

太好了。

Yay.

你耳朵上的褶皱和凹凸不平的部分非常重要。

The folds and wrinkly bits of your ears are very important.

它们告诉你的大脑声音是从哪里来的，是从上面还是下面，前面还是后面。

They tell your brain where the sound is coming from, from above or below, in front or behind you.

我们的声波正在进入耳洞。

Our sound wave is going into the ear hole.

等等！

Hang on!

哦，这里面好黑。

Oh, it's dark in here.

还有点黏糊糊的。

And a little sticky.

欢迎来到耳道，也就是耳朵的内部。

Welcome to the ear canal, the inside of an ear.

哦，那这些黏糊糊的东西一定是——

Oh, so this sticky stuff must be-

耳屎。

Ear wax

任务取消。

Abort mission.

我们被困在这黏糊糊的东西里了。

We're stuck in the goo.

别慌，Nij。

Don't panic, Nij.

耳屎是好事。

Ear wax is a good thing.

我觉得它们是用来保护耳朵的。

I think they're for protecting your ear.

没错。

That's right.

耳垢能保护我们的耳道，挡住灰尘、污垢，有时候甚至能拦住不小心爬进来的小虫子。

Ear wax guards our ear canal by catching dust, dirt, sometimes even tiny bugs that might have accidentally crawled in.

哦。

Oh.

谢谢你给我这些噩梦，Viji。

Thanks for those nightmares, Viji.

但我们是声波，记得吗？

But we're sound waves, remember?

我们不能停在这里。

We don't get to stop here.

能量会继续往里推，直到撞上……

The energy keeps pushing further inside until it bounces up against...

哎哟。

Oof.

我们撞到死胡同了。

We hit a dead end.

不完全是。

Not exactly.

这是耳膜。

This is the eardrum.

它是耳朵最重要的部分之一。

It's one of the most important parts of the ear.

耳膜这个名字对耳朵里的东西来说挺有趣的。

Eardrum is a pretty funny name for something inside an ear.

哇。

Whoa.

我以前可没敲过这样的鼓。

I've never played a drum like this before.

它是干什么的？

What does it do?

也许它把所有声音都收进身体里，然后在耳朵里发出响亮的声音。

Maybe it takes all of the sound and puts it inside your body so it can make a loud sound in your ear.

对。

Yes.

它是一层薄但坚韧的皮肤，紧紧绷在耳道里。

It's a thin but tough piece of skin stretched tightly across the ear canal.

当声波到达时，声音会让鼓膜振动。

When a sound wave reaches it, the sound makes the eardrum vibrate.

这些振动会传递给耳朵的下一个部分。

Those vibrations are passed on to the next part of the ear.

那声波会继续前进吗？

And the wave keeps going?

另一边是什么？

What's on the other side?

我们能进去看看吗？

Can we go into it and see?

好，声波们，你们进去吧。

All right, sound waves, through you go.

现在我们到了中耳。

Now we are in the middle ear.

哎呀，这里有点挤，而且没什么好看的。

Ugh, it's a little tight in here, and there's not much to see.

这里有三样重要的东西。

There's three important things to see.

人体里最小的三块骨头。

The three smallest bones in the human body.

它们能帮我动耳朵吗？

Do they help me wiggle my ears?

不太行。

Not quite.

第一块骨头叫锤骨，它连着鼓膜。

The first bone is called the hammer, and it's attached to the eardrum.

当声波让鼓膜动的时候，锤骨也跟着动。

When sound waves make the eardrum move, the hammer moves, too.

就像接力赛的第一棒，把声音的能量传给下一块骨头。

It's like the first runner in a relay race, passing the sound's energy to the next bone.

快，我们给它们一个声音传传看。

Quick, let's give them a sound to pass.

你好。

Hello.

哦，看，开始了。

Oh, look, it's happening.

锤骨在敲打。

The hammer is banging.

咚咚，咚咚，咚咚，咚，咚。

Ba-boom, ba-boom, ba-boom, boom, boom.

它让第二块骨头动起来了。

It's making the second bone move.

那就是砧骨。

And that's the anvil.

一旦砧骨开始移动，它就会把声音传给镫骨，这是三块骨头中最小的。

Once the anvil starts moving, it passes the sound to the stirrup, the smallest bone of all three.

对，你看，它也在动。

Yeah, look, it's moving, too.

它比一粒米还小。

It's smaller than a grain of rice.

这些骨头真小。

These bones are so tiny.

我们真的需要它们吗？

Do we really need them?

当然需要。

We sure do.

耳朵的下一部分，也就是内耳，充满了液体，声波进入时可能会损失很多能量。

The next part of the ear, the inner ear, is filled with fluid, and sound waves can lose a lot of energy getting into it.

这些小骨头的作用是在声波进入内耳之前增强它们。

These tiny bones help by making them stronger before they enter the inner ear.

所以这些骨头把声波汇聚在一起，让它们足够强，能传到耳朵的下一个部分。

So the bones bring the sound waves all together so they're strong enough to reach the next part of the ear.

准备好去游泳吧。

Get ready to go swimming.

我们在水下。

We are underwater.

而且这个房间是螺旋形的。

And this room is shaped like a spiral.

像蜗牛壳一样。

Like a snail shell.

你耳朵里这个神奇的部分叫做耳蜗。

This amazing part of your ear is called the cochlea.

它确实看起来像蜗牛壳，而且里面充满了液体。

It does look like a snail shell, and it's filled with liquid.

哇！

Whoa!

声波来了。

Here comes a sound wave.

到处都在晃动。

Everything's wobbling.

耳蜗里面那些毛茸茸的东西是什么？

What's all that fuzzy stuff along the inside of the cochlea?

看起来像海草。

It looks like seaweed.

确实像。

It does.

它们是毛细胞，但跟我们头上长的头发不一样。

They're hair cells, but they're not like the hair that grows on our heads.

它们是微小的声音传感器。

They're tiny sound sensors.

它们有成千上万个。

There are thousands of them.

看起来耳蜗像是铺了一层毛茸茸的垫子。

It looks like the cochlea is covered in a fluffy mat.

当声波穿过耳朵时，这层垫子会像波浪一样动，毛细胞也跟着一起摇摆。

When sound waves travel through the ear, the mat moves like a wave, and the hair cells sway together with the mat.

看，它们现在就在动。

Look, they're doing it now.

就像在一起跳舞一样。

It's like they're dancing together.

毛细胞有两种，分别叫内毛细胞和外毛细胞。

There are two kinds of hair cells, called inner hair cells and outer hair cells.

它们是干什么的？

What do they do?

内毛细胞的作用是向大脑发出信号，告诉大脑有声音来了。

The inner hair cells are there to signal to the brain that a sound has arrived.

有些内毛细胞对尖细的高音有反应，有些则对低沉浑厚的声音有反应。

Some of them respond to more squeaky, high sounds, and some of them respond to low, rumbly sounds.

看，水在动。

Look, the water's moving.

又来了一波声波。

Here comes another sound wave.

那听起来像自行车铃吗？

Did that sound like a bike bell?

一个明亮的高音。

A bright, high sound.

高音会让螺旋的底部动起来，然后带动所有毛细胞一起摆动。

High sounds make the bottom of the spiral move, and that triggers all the hair cells to wiggle.

那个声音真酷。

That sound is cool.

我们跟着它走。

Let's follow it.

是一头牛。

It's a cow.

哞。

Moo.

那是低音。

That's a low sound.

像这样好听的低音会让螺旋的末端动起来，并触发耳蜗顶端的毛细胞摆动。

A nice bassy sound like this makes the end of the spiral move and triggers the hair cells at the tip of the cochlea to wiggle.

所以，内毛细胞就是声音传感器。

So, the inner hair cells are the sound sensors.

那其他那些毛是干什么的？

What do all the other hairs do?

这里面有成千上万根呢。

There are thousands of them in here.

其余的都是放大器。

The rest are amplifiers.

它们就像一群热心观众，当微弱的声音波进来时，哪怕是耳语，它们也会把波放大。

They are like the helpful crowd making the wave bigger when the soft sound waves come in, even a whisper.

但这些仍然只是声波。

But these are still just waves.

实际上还没有真正听到任何声音。

Nothing's actually being heard yet.

但我们走了这么长的路。

But we've been on such a long journey.

穿过空气，经过耳垢，穿过鼓膜，越过最小的骨头，进入耳蜗。

Through the air, past the earwax, through the eardrum, across the tiniest bones, and into the cochlea.

但还没有人真正听到任何声音？

But nobody's actually heard anything yet?

没错。

That's right.

到目前为止，一切都只是大量的运动，一条长长的振动链。

Until now, it's all been a lot of movement, a long chain of vibrations.

但内毛细胞还做了另一件令人难以置信的事情。

But the inner hair cells do something else incredible.

它们把运动转化成微小的电信号。

They turn the movement into tiny electrical messages.

看，那些毛在摆动，还在放电。

Look, the hairs are wiggling, and zapping.

嗖嗖嗖。

Zip, zip, zip.

这是怎么回事？

What's happening?

它们是给大脑的信号。

They're signals to our brain.

它们被发送到你的身体里，这样就能让身体知道你正在听到声音。

It sends them into your body so, so that it can let your body know that you're hearing something.

对。

Yes.

这些毛细胞都连接在一根长长的电缆上，叫做听神经。

The hair cells are all connected to a long cable called the auditory nerve.

每当毛细胞摆动时，就会产生一个电信号，沿着这根线传下去。

Whenever the hair cells wiggle, it makes an electrical message that's sent down the cable.

里面全是信号。

It's full of messages.

哦，我们到大脑了。

Oh, we're in the brain.

大脑就像一台超级计算机。

The brain is like a supercomputer.

它要处理从听觉神经以及沿途许多其他站点传来的各种声音信号。

It's responding to all the different sound signals that come through the auditory nerve and many other stations along the way.

这就是大脑。

This is the brain.

我正在接收左耳和右耳传来的信号。

I'm receiving signals from the left and the right ears.

哇，大脑能同时接收两只耳朵的信号。

Whoa, the brain gets signals from both ears.

当然。

Of course.

你可以同时从两只耳朵听到不同的声音。

You can hear different things from both ears at the same time.

酷，但有时候你不知道声音是从哪里来的。

Cool, but sometimes you don't know where the sound comes from.

所以你的大脑需要很快地问很多问题。

So your brain needs to ask a lot of questions very quickly.

哪只耳朵先听到声音？

Which ear heard the sound first?

哪只耳朵听到的声音更响？

Which ear heard it louder?

所有这些线索都帮助你的大脑判断声音来自哪里。

All those clues help your brain work out where the sound's coming from.

左边有一只狗。

There's a dog on the left.

上面有一只喜鹊。

There's a magpie above.

我们查一下记忆，看看是不是俯冲季节。

Let's check in with memory to see if it's swooping season.

我们可能需要把它升级为高度警戒状态。

We might need to move that up to a high alert status.

重要的声音从后面传来。

Important sound coming from behind.

然后你的大脑会问一个更重要的问题。

And then your brain asks something even more important.

我该注意吗？

Should I pay attention?

那听起来像一台旧冰箱。

That sounds like an old fridge.

对，那种声音我们称之为背景噪音，所以你的大脑判断它不重要。

Yep, that sort of stuff is what we call background noise, so your brain has decided it's not important.

你几乎都不会注意到它。

You almost don't even notice it.

你的大脑一直在判断哪些信息最重要。

Your brain is constantly deciding which information matters the most.

对，不然的话，你总是得想着每一个声音。

Yeah, otherwise, you'd be trying to think about every sound all the time.

那会让人很困惑。

That would be very confusing.

那会让人压力很大。

It would be stressful.

如果我听到所有这些声音，我根本睡不着。

I could never fall asleep if I heard all that.

没错。

Exactly.

你的大脑帮你专注于重要的事情。

Your brain helps you focus on what's important.

火警警报的声音。

The sound of fire alarms.

对。

Way.

或者消防车、警车的声音。

Or a fire truck or a police car.

这些声音确实需要注意。

Those are definitely sounds to pay attention to.

或者像有人喊你的名字、汽车喇叭声，或者你最喜欢的歌。

Or like someone calling your name, or a car horn, or your favorite song.

就像我们乐队排练时该练的那首歌。

Like the one we're supposed to be practicing at band practice.

拜托。

Come on.

我们回来了。

We're back.

谢谢你给我们讲解听觉是怎么工作的，Viji博士。

Thanks for showing us how hearing works, Dr. Viji.

谢谢你，Viji。

Thank you, Viji.

还帮我们冲浪声波。

And helping us surf the sound waves.

这其实是个不错的歌名。

That's actually a good song title.

我得记下来。

I should write that down.

没问题。

No problem.

准备好演奏了吗？

Ready to play?

一，二。

One, two.

一、二、三、四。

One, two, three, four.

所以，麦肯齐、汤姆和哈里，所有的声音都是振动。

So Mackenzie, Tom, and Harry, all sound is vibration.

它通过声波传播。

It moves through sound waves.

声波通过碰撞和挤压微小粒子来传播，将振动向外传递，直到它被你的耳廓捕捉到。

Sound waves move by bumping and squeezing tiny particles, sending the vibration outwards until it gets caught in the pinna of your ear.

就是那些有褶皱的地方。

In the foldy bits.

就像一张网。

It's like a net.

振动会在你的耳朵内部移动。

The vibrations move inside your ear.

它们不会卡在耳垢里。

They don't get stuck in earwax.

然后撞到那层薄薄的皮肤，也就是耳膜。

And bounce against the thin piece of skin called the eardrum.

咚咚咚。

Boom, boom, boom.

咚咚。

Boom, boom.

耳膜把声音传递到你身体里最小的三块骨头上。

The eardrum moves the sound across the three smallest bones in your body.

锤骨、砧骨和镫骨。

The hammer, the anvil, and the stirrup.

直到振动传到耳蜗，也就是你的内耳。

Until the vibration makes it to the cochlea, your inner ear.

它的形状像蜗牛。

It's shaped like a snail.

在耳蜗里，螺旋起点的毛细胞对高音振动，螺旋末端的毛细胞对低音振动。

Inside the cochlea, the hairs at the start of the spiral vibrate to high sounds, and the hairs at the end of the spiral vibrate to low sounds.

它们会摆动。

They wiggle.

当它们摆动时，会向一条特殊的神经发送微小的电信号，这条神经再把信号传到大脑。

And when they wiggle, they send tiny electrical signals into a special nerve that takes them to the brain.

然后你就能听到声音了。

Then you can hear it.

你的大脑一直在听，但它会判断哪些声音重要，哪些不那么重要。

Your brain is always listening, but it's deciding what sounds are important and not so important.

所以下次你在一个安静的地方，花点时间听听周围所有的声音吧。

So next time you're in a quiet place, take a moment to listen to all the sounds that surround you.

你好，我是R.A. Spratt，儿童作家，创作了《Friday Barnes》《Nanny Piggins》和《Pesky Kids》系列。

Hello, I'm R.A. Spratt, the children's author behind the Friday Barnes, Nanny Piggins, and Pesky Kids series.

我非常兴奋能通过ABC Listen带来我的播客《R.A. Spratt的睡前故事》。

And I'm super excited to bring my podcast, Bedtime Stories with R.A. Spratt, to ABC Listen.

所以，加入我和Nanny Piggins——世界上最迷人的飞猪——让我们一起带你进入一个充满冒险、混乱和巧克力的世界。

So join me and Nanny Piggins, the world's most glamorous flying pig, and let us transport you to a world of adventure, mayhem, and chocolate.

在ABC Listen应用的儿童专区里，找到《R.A. Spratt的睡前故事》。

Find Bedtime Stories with R.A. Spratt on the kids tab of the ABC Listen app.