Why helmets don't prevent concussions -- and what might | David Camarillo

翻译人员: Chen Wang 校对人员: Diana Li

The word concussion evokes a fear these days more so than it ever has,

“脑震荡”一词从未引起过如此之大的恐慌

我自己也患过脑震荡

and I know this personally.

I played 10 years of football,

我曾打过十年橄榄球

was struck in the head thousands of times.

数千次被球打中脑袋

And I have to tell you, though, what was much worse than that

但我可以告诉你

自行车事故中我遭受的脑震荡要更为严重

was a pair of bike accidents I had where I suffered concussions,

现如今当我站在你面前时

and I'm still dealing with the effects of the most recent one

我还在从最近的那次脑震荡中恢复

today as I stand in front of you.

There is a fear around concussion

对脑震荡的恐惧

有些是有道理的

that does have some evidence behind it.

There is information that a repeated history of concussion

有证据表明 反复多次脑震荡

can lead to early dementia, such as Alzheimer's,

会导致早期痴呆 比如阿耳茨海默氏病

and chronic traumatic encephalopathy.

也会导致慢性的创伤性脑病

That was the subject of the Will Smith movie "Concussion."

这是威尔•史密斯主演的电影《震荡效应》的主题

And so everybody is caught up in football and what they see in the military,

几乎每个人在橄榄球比赛中 或是在部队里 都会遭受脑震荡

但你可能不知道

but you may not know

that bike riding is the leading cause of concussion for kids,

对孩子们而言 骑自行车才是脑震荡的主要成因

sports-related concussion, that is.

即运动相关脑震荡

我还想告诉在座各位一件事

And so another thing that I should tell you

that you may not know

你们或许也不知道

is that the helmets that are worn in bicycling and football

诸如自行车和橄榄球等运动

and many activities,

所规定佩戴的头盔

they're not designed or tested

并不是为了防止或减轻脑震荡而设计的

for how well they can protect your children against concussion.

They're in fact designed and tested

事实上

for their ability to protect against skull fracture.

此类头盔的目的在于保护头骨 预防头骨骨折

And so I get this question all the time from parents,

家长们总是问我这样一个问题

and they ask me,

他们问我

“你会让你自己的小孩儿打橄榄球吗？”

"Would you let your own child play football?"

Or, "Should I let my child play soccer?"

或者“我应该让我小孩儿踢足球吗？”

And I think that as a field,

我认为从一个学科领域的角度来讲

we're a long way from giving an answer with any kind of confidence there.

我们远没有信心在此回答这样一个问题

So I look at that question from a bit of a different lens,

所以我从另外一个角度思考了这个问题

我想知道 我们如何预防脑震荡？

and I want to know, how can we prevent concussion?

Is that even possible?

这能做到吗？

And most experts think that it's not,

绝大多数专家认为不能

but the work that we're doing in my lab

但我的实验室目前所从事的研究

is starting to reveal more of the details around concussion

将揭示脑震荡的更多细节

从而我们会对脑震荡有更深刻的认知

so that we can have a better understanding.

The reason we're able to prevent skull fracture with helmets

戴头盔能预防颅骨骨折的原因非常简单

is because it's pretty simple. We know how it works.

我们知道这一原理

Concussion has been much more of a mystery.

而脑震荡至今仍是未解之谜

So to give you a sense of what might be happening in a concussion,

为了让在座各位对脑震荡有更直观的了解

I want to show you the video here

我要放一段影片

that you see when you type into Google,

你可以在谷歌搜索如下字样

"What is a concussion?"

What is a concussion? 什么是脑震荡?

The CDC website comes up,

然后打开CDC（美国疾病控制与预防中心）网页

and this video essentially tells the whole story.

网页上的这段视频就会讲述脑震荡的成因

What you see is the head moves forward,

你可以看到：头部向前移动

the brain lags behind,

脑组织移动延后

then the brain catches up

接着脑组织跟了上来也向前移

and smashes into the skull.

撞向颅骨

It rebounds off the skull

被颅骨弹回

and then proceeds to run into the other side of the skull.

然后向另一边颅骨撞去

And what you'll notice is highlighted in this video from the CDC,

CDC影片中高亮的那部分

which I'll note was funded by the NFL,

顺带说一下 这一影片由 NFL（美国国家橄榄球联盟）资助

is that the outer surface of the brain,

是脑组织的外部边缘

where it was to have smashed into the skull,

这部分脑组织之前曾撞向颅骨

looks like it's been damaged or injured, so it's on the outer surface of the brain.

看起来它受到了损伤 所以高亮部分是在脑组织的外部边缘

And what I'd like to do with this video

我放这段影片

is to tell you that there are some aspects that are probably right,

是为了告诉各位 这段影片的部分内容

indicative of what the scientists think happens with concussion,

或许确实正确地表述了科学家对脑震荡的理解

but there's probably more that's wrong with this video.

但这段影片更多地方是错误的

其中一点我个人是同意的 我相信绝大多数专家也同意

So one thing that I do agree with, and I think most experts would,

is that the brain does have these dynamics.

那就是脑部确实有这样的动态

It does lag behind the skull

它的运动迟于颅骨

and then catch up and move back and forth and oscillate.

接着逐渐追赶上 并向前向后振动

That we think is true.

这一点上我们认为它是正确的

However, the amount of motion you see in the brain in this video

然而 视频中所示的脑部的运动大小

可能并不准确

is probably not right at all.

There's very little room in the cranial vault,

颅顶的空间极小

只有几微米

only a few millimeters,

and it's filled entirely with cerebral spinal fluid,

同时这些空间填满了脑脊液

这些脑脊液对脑部来说是一个保护层

which acts as a protective layer.

And so the brain as a whole probably moves very little inside the skull.

所以说 整体来看 脑部在颅骨内的移动极为微小

The other problem with this video

视频中还有另外一个问题

is that the brain is shown

视频中所示的脑部

as a kind of rigid whole as it moves around,

在它移动时像是一个坚硬体

and that's not true either.

这也是错的

Your brain is one of the softest substances in your body,

人类的大脑是人体上最柔软的物质之一

你可以把它想象成果冻

and you can think of it kind of like jello.

So as your head is moving back and forth,

所以当头部前后晃动时

your brain is twisting and turning and contorting,

脑部在旋转、扭曲

and the tissue is getting stretched.

部分组织会被拉抻

And so most experts, I think, would agree

我认为绝大多数专家都会同意这样一个观点

that concussion is not likely to be something that's happening

脑震荡可能不是发生在

on this outer surface of the brain,

脑部的外部边缘

but rather it's something that's much deeper

而是发生在脑部的深处

towards the center of the brain.

接近脑部中央的位置

Now, the way that we're approaching this problem

当下 我们通过这样一个设备研究这一问题

to try to understand the mechanisms of concussion

从而试图理解脑震荡产生机制

and to figure out if we can prevent it

并确定我们是否可以防治脑震荡

我们所采用的是这样一个设备

is we are using a device like this.

It's a mouthguard.

它是个牙套

It has sensors in it that are essentially the same

它里面包含了

和手机内置传感器类似的

that are in your cell phone:

accelerometers, gyroscopes,

加速计和陀螺仪

and when someone is struck in the head,

当一个人被击中头部时

it can tell you how their head moved

它可以以每秒钟一千次的速度

记录下头部的移动方式

at a thousand samples per second.

The principle behind the mouthguard is this:

这个牙套的原理在于

it fits onto your teeth.

它固定在牙齿上

Your teeth are one of the hardest substances in your body.

而牙齿是人体内最坚硬的物质之一

So it rigidly couples to your skull

所以相当于它直接连接在颅骨上

and gives you the most precise possible measurement

从而可以最为精确地测算出

of how the skull moves.

颅骨的运动模式

People have tried other approaches, with helmets.

研究者们也曾试验过其他方法 比如头盔

We've looked at other sensors that go on your skin,

我们也曾实验过 将传感器贴在皮肤上

and they all simply move around too much,

但是它们移动得太多了

and so we found that this is the only reliable way

所以我们发现这是可以得到精确测算的

to take a good measurement.

唯一可信方式

So now that we've got this device, we can go beyond studying cadavers,

现如今我们有了这一设备 就可以不仅限于研究尸体了

because you can only learn so much about concussion

因为在尸体身上对脑震荡的研究

已经近乎到达极限

from studying a cadaver,

and we want to learn and study live humans.

我们想要进行活体实验

So where can we find a group of willing volunteers

在哪里才可以找到一组

愿意经常出去 把头乱撞

to go out and smash their heads into each other on a regular basis

and sustain concussion?

从而患上脑震荡的志愿者呢？

Well, I was one of them,

嗯 我就是其中一员

and it's your local friendly Stanford football team.

他们是你们友好的斯坦福橄榄球队

So this is our laboratory,

所以这就是我们的实验室

and I want to show you

我将向各位展示

我们通过这一设备测量到的第一例脑震荡

the first concussion we measured with this device.

One of the things that I should point out is the device has this gyroscope in it,

我需要指出一点：该设备中含有陀螺仪

and that allows you to measure the rotation of the head.

它可以测出头部的旋转

Most experts think that that's the critical factor

而绝大多数专家认为

头部的旋转或许是解释脑震荡成因的关键因素

that might start to tell us what is happening in concussion.

So please watch this video.

请看这段视频

Announcer: Cougars bring extra people late, but Luck has time,

解说员：Cougars带了大批人马但是已经晚了 Luck现在有机会了

and Winslow is crushed.

Winslow被撞了

希望他还好

I hope he's all right.

(Audience roars)

（观众吼叫）

Top of your screen,

屏幕上方

你可以看到他选择了这一短程球门柱路线

you'll see him come on just this little post route,

get separation, safety.

被分开 安全了

Here it comes at you in real speed. You'll hear this.

现在您看到的是常速回放 你会听到

The hit delivered by --

由--的这一击

David Camarillo: Sorry, three times is probably a little excessive there.

抱歉 放了三次可能有点儿多

但你应该会看明白

But you get the idea.

So when you look at just the film here,

当你看这段影片时

pretty much the only thing you can see is he got hit really hard and he was hurt.

你可能只会看出 他被击打得很严重 他受伤了

但当我们从他戴的牙套中

But when we extract the data

out of the mouthguard that he was wearing,

提取到数据后

we can see much more detail, much richer information.

我们可以看到更多细节、更多信息

And one of the things that we noticed here

我们可以注意到

他的左下侧面罩被击中

is that he was struck in the lower left side of his face mask.

所以有点违反直觉的是

And so that did something first that was a little counterintuitive.

His head did not move to the right.

他的头并没有向右移

相反 它首先向左旋转

In fact, it rotated first to the left.

接着颈部开始弯曲

Then as the neck began to compress,

the force of the blow caused it to whip back to the right.

最后这一下击打的力度才让头部向右移动

这样的左右移动是鞭打现象的一种

So this left-right motion was sort of a whiplash-type phenomenon,

and we think that is probably what led to the brain injury.

我们认为也许是这样的移动 造成了脑损伤

Now, this device is only limited in such that it can measure the skull motion,

当下 这个设备仅能测量出颅骨的运动

但我们真正想知道的是 脑部内部的情形

but what we really want to know is what's happening inside of the brain.

So we collaborate with Svein Kleiven's group in Sweden.

所以我们与瑞典的Svein Kleiven团队合作

他们研发出了一种脑部有限元素模型

They've developed a finite element model of the brain.

And so this is a simulation

这是一个模拟图

using the data from our mouthguard from the injury I just showed you,

模拟所用数据是刚才影片中那次受伤后 我们从牙套中得到的数据

你会看到

and what you see is the brain --

this is a cross-section right in the front

如我之前所述

of the brain twisting and contorting as I mentioned.

脑部正前方左右脑交界处发生旋转、扭曲

So you can see this doesn't look a lot like the CDC video.

所以这和CDC视频中所描述的并不一致

Now, the colors that you're looking at

这里不同颜色所代表的是

are how much the brain tissue is being stretched.

脑组织被拉伸的程度

And so the red is 50 percent.

红色代表百分之五十

这意味着红色区域的这部分脑组织

That means the brain has been stretched to 50 percent of its original length,

the tissue in that particular area.

被拉长了原来长度的50%

And the main thing I want to draw your attention to is this red spot.

值得注意的是红色点状区域的分布

So the red spot is very close to the center of the brain,

它们非常接近脑部中心

and relatively speaking,

相对而言

you don't see a lot of colors like that on the exterior surface

和CDC影片中所示不同

as the CDC video showed.

脑组织外部红色区域较少

Now, to explain a little more detail

接下来 我会更详细地阐释

about how we think concussion might be happening,

我们对脑震荡成因的观点

one thing I should mention

值得一提的是

is that we and others have observed that a concussion is more likely

我们和其他同行都观察到

when you're struck and your head rotates in this direction.

如果头部被击打 并像这样旋转 更容易造成脑震荡

This is more common in sports like football,

橄榄球等运动中这种情况（前后晃动）更为常见 但这种（左右晃动）似乎更为危险

but this seems to be more dangerous. So what might be happening there?

所以这种情况中脑部发生了什么呢？

Well, one thing that you'll notice in the human brain

值得注意的是 人类大脑与其他动物的并不相同

that is different than other animals

主要差异在于

is we have these two very large lobes.

我们有两块儿相当大的大脑额叶

We have the right brain and the left brain.

它们是我们的右脑和左脑

这幅图中值得注意的是

And the key thing to notice in this figure here

左右脑中间的正下方

is that right down the center of the right brain and the left brain

there's a large fissure that goes deep into the brain.

有一个深入脑组织的裂缝

And in that fissure, what you can't see in this image,

虽然这幅图中看不到

you'll have to trust me,

但你得相信我

there is a fibrous sheet of tissue.

裂缝中有一层纤维化组织

It's called the falx,

它被称为脑镰

and it runs from the front of your head all the way to the back of your head,

脑镰连通头部的最前方和最后方

它很硬

and it's quite stiff.

And so what that allows for is when you're struck

当你头部被击中

and your head rotates in this left-right direction,

并左右旋转时

forces can rapidly transmit right down to the center of your brain.

脑镰可以让受力迅速传至脑部中央

Now, what's there at the bottom of this fissure?

所以 裂缝的底部有什么？

那里有脑部的“线路”

It's the wiring of your brain,

and in fact this red bundle here at the bottom of that fissure

事实上 裂缝底部红色的那一捆“线路”

is the single largest fiber bundle

是最大的单个纤维束

that is the wiring that connects the right and left sides of your brain.

也就是它连接着你们的左右脑

It's called the corpus callosum.

它被称为脑胼胝体

And we think that this might be

我们认为

one of the most common mechanisms of concussion,

这也许是脑震荡最为常见的成因

and as the forces move down, they strike the corpus callosum,

击打力向下移动 撞机脑胼胝体

导致左右脑之间的连接断裂

it causes a dissociation between your right and your left brain

这样就可以脑震荡的一些症状

and could explain some of the symptoms of concussion.

This finding is also consistent of what we've seen

此外 这项发现与我之前提过的

in this brain disease that I mentioned, chronic traumatic encephalopathy.

脑震荡引起的诸如慢性创伤性脑病等 脑部疾病的症状相符

So this is an image of a middle-aged ex-professional football player,

这是一个中年前橄榄球职业运动员的脑部图片

我想指出的是 如果你仔细观察脑胼胝体

and the thing that I want to point out is if you look at the corpus callosum,

我们看一下上一页的这张图片 这是一个正常脑胼胝体的大小

and I'll page back here so you can see the size of a normal corpus callosum

这是那位患有慢性创伤性脑病的脑胼胝体

and the size of the person here who has chronic traumatic encephalopathy,

it is greatly atrophied.

它大幅萎缩了

脑室的大小也有变化

And the same goes for all of the space in the ventricles.

These ventricles are much larger.

然而它们却变大很多

And so all of this tissue near the center of the brain

这意味着脑部中央附近的组织细胞

has died off over time.

已经逐渐凋亡

这也印证了我们的研究发现

So what we're learning is indeed consistent.

Now, there is some good news here,

但是 这里我也要带来一些好消息

and I hope to give you a sense of hope by the end of this talk.

希望能给在座各位一些希望

One of the things that we've noticed,

我们注意到一些损伤机制的细节

specifically about this mechanism of injury,

虽然力在裂缝中的向下传导非常迅速

is although there's a rapid transmission of the forces down this fissure,

它还是需要一定的时间的

it still takes a defined amount of time.

And what we think is that if we can slow the head down just enough

所以我们设想 如果能够减缓头部的向下移动

so that the brain does not lag behind the skull

那么脑部运动就不会落后于颅骨

而是与颅骨同步

but instead it moves in synchrony with the skull,

then we might be able to prevent this mechanism of concussion.

这样我们或许就能预防脑震荡

So how can we slow the head down?

那我们该如何减缓头部的向下移动？

(Laughter)

（笑声）

A gigantic helmet.

可以佩戴巨型头盔

So with more space, you have more time,

空间变大 缓冲时间就会变长

and this is a bit of a joke, but some of you may have seen this.

当然这是个玩笑 虽然你们有人可能见过这个

This is bubble soccer, and it's a real sport.

这是泡泡足球 而且它真是一项运动

In fact, I saw some young adults

事实上 前几天

playing this sport down the street from my house the other day,

我就在我家附近的街上看到一些年轻人在玩儿它

and as far as I know there have been no reported concussions.

据我所知 没有这种运动中发生脑震荡的报道

(Laughter)

（笑声）

But in all seriousness, this principle does work,

但严肃地说 这一原则确实有效

but this has gone too far.

但它有点过头儿了

This isn't something that's practical for bike riding or playing football.

毕竟对于自行车和橄榄球运动来讲 这不大现实

And so we are collaborating with a company in Sweden called Hövding.

目前 我们正和瑞典Hövding公司合作 研发一个产品

Some of you may have seen their work,

可能有人见过它

and they're using the same principle of air to give you some extra space

它实际上运用了同一项原则 利用空气提供更多空间

to prevent concussion.

从而预防脑震荡

Kids, don't try this at home please.

小孩子请勿在家尝试

This stuntman does not have a helmet.

这个特技演员没有戴头盔

He instead has a neck collar,

而是戴了一个颈环

and this neck collar has sensors in it,

这个颈环内置传感器

这些传感器和我们的牙套中的传感器同属一个类型

the same type of sensors that are in our mouthguard,

and it detects when he's likely to have a fall,

当骑行者要摔倒时 它可以感测到

and there's an airbag that explodes and triggers,

并且弹出安全气囊

the same way that an airbag works in your car, essentially.

这一引发机制和汽车中的基本一致

我的实验室对这一设备进行了一系列实验

And in the experiments we've done in my lab with their device,

we found that it can greatly reduce the risk of concussion in some scenarios

我们发现与普通自行车头盔相比

compared to a normal bicycle helmet.

这一设备在一些情境下可以大幅降低脑震荡风险

So it's a pretty exciting development.

这是个很令人激动的新发展

But in order for us to actually realize the benefits of technology

但为了真正利用这一可以预防脑震荡的技术

that can prevent concussion,

it needs to meet regulations.

它必须得符合监管的要求

That's a reality.

这是个现实问题

这一设备目前在欧洲出售

And this device is for sale in Europe

但目前却没有 很可能近期都不会 在美国出售

but is not for sale in the US, and probably won't be any time soon.

So I wanted to tell you why.

我会告诉各位这是为什么

There are some good reasons and then there are some not so good reasons.

有些原因很合理 而有些却不是

Bike helmets are federally regulated.

自行车头盔由联邦政府监管

The Consumer Product Safety Commission has been given jurisdiction

美国消费品安全委员会有权

to approve any bike helmet for sale,

批准自行车头盔产品上市

他们用这样的测试方法

and this is the test they use.

This is back to what I was telling you at the beginning about skull fracture.

这又回到了我们开始时候谈到的颅骨骨折问题

而这正是这一测试的目的

That's what this test is for.

这一测试很重要

And that's an important thing to do.

它能挽救生命 但我得说 它不够全面

It can save your life, but it's not sufficient, I would say.

So for example, one thing this test doesn't evaluate

比如说 这一测试没有评估

安全气囊能否在正确地时间地点弹出

is it doesn't tell you is that airbag going to trigger

at the right time and place, and not trigger when it doesn't need to?

也没有评估它在不需要弹出的情况是否会弹出

Similarly, it's not going to tell you

同样 这一测试也不能判断

is this helmet likely to prevent concussion or not?

这一头盔是否能够预防脑震荡

And if you look at football helmets, which aren't regulated,

其实橄榄球头盔虽然未被联邦政府监管

但他们的测试基本相同

they still have a very similar test.

They're not regulated by the government, anyway.

虽然它们并未被政府监管

They have an industry body, which is the way most industries work.

但如同绝大多数行业一样 有一个行业机构负责此事

但我得说 这一机构极力反对更新它们的标准

But this industry body, I can tell you, has been quite resistant

to updating their standards.

所以我们实验室不仅研究脑震荡机制

So in my lab, we are working on not only the mechanism of concussion,

还想研究如何才能采用更好的测试标准

but we want to understand how can we have better test standards?

我们希望政府可以利用这类信息鼓励创新

And we hope that the government can use this type of information

to encourage innovation

by letting consumers know

让消费者了解某一特定头盔的保护能力

how protected are you with a given helmet.

And I want to bring this back finally to the original question I asked,

最后我想要回到最初我常被问到的那个问题

which is, would I feel comfortable letting my child play football

我会让我的小孩打橄榄球吗？

or ride a bicycle?

会让它骑自行车吗？

And this might be just a result of my own traumatic experience.

因为我自己的痛苦经历

I'm much more nervous about my daughter, Rose, riding a bicycle.

当我女儿Rose骑自行车时 我会非常紧张

So she's a year and a half old,

她现在才一岁半

and she's already, well, wants to anyway, race down the streets of San Francisco.

就已经很想冲下旧金山的街道

这张图片拍摄于某条街道的末尾

This is the bottom of one of these streets.

And so my personal goal is to -- and I believe this is possible --

所以我个人的目标是进一步研发这些技术

is to further develop these technologies,

而且我认为这一肯能行很大

and in fact, we're working on something in my lab in particular

事实上 我的实验室尤其致力于研究

that really makes optimal use of the given space of a helmet.

头盔内部空间的最佳使用方式

And I am confident that we will be able to,

我敢肯定我们能在我女儿可以骑两轮自行车前

before she's ready to ride a two-wheeler,

做到这一点

have something available

研发出能够真正减少脑震荡风险 且符合监管机构要求的头盔

that can in fact really reduce the risk of concussion

and comply with regulatory bodies.

And so what I'd like to do --

我希望再过几年

and I know that this is for some of you of more immediate nature,

I've got a couple years here --

我可以告诉孩子家长和祖父母

is to be able to tell parents and grandparents when I'm asked,

it is safe and healthy for your children to engage in these activities.

孩子们可以安全、健康地骑自行车、打橄榄球

And I'm very fortunate to have a wonderful team at Stanford

非常有幸我能在斯坦福有这样一个

that's working hard on this.

致力于研究脑震荡的团队

So I hope to come back in a few years with the final story,

我希望过几年我可以再来讲最后的故事

but for now I will tell you,

但现在我可以各位

please don't just be afraid when you hear the word concussion.

当你听到脑震荡一词时不要害怕

There is hope.

这还有希望

Thank you.

谢谢各位

（掌声）

(Applause)