TED演讲:为什么头盔不能预防脑震荡?(3)

 So one thing that I do agree with, and I think most experts would, is that the brain does have these dynamics¹. 其中一点我个人是同意的，我相信绝大多数专家也同意，那就是脑部确实有这样的动态。

It does lag behind the skull² and then catch up and move back and forth³ and oscillate. That we think is true. 它的运动迟于颅骨，接着逐渐追赶上，并向前向后振动，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 is probably not right at all. 然而，视频中所示的脑部的运动大小，可能并不准确。

There's very little room in the cranial vault⁴, only a few millimeters, 颅顶的空间极小，只有几微米，

and it's filled entirely⁵ with cerebral⁶ spinal⁷ fluid, which acts as a protective layer. 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。

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 is that the brain is shown as a kind of rigid⁸ whole as it moves around, and that's not true either. 视频中还有另外一个问题，视频中所示的脑部，在它移动时像是一个坚硬体，这也是错的。

Your brain is one of the softest substances in your body, and you can think of it kind of like jello⁹. 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。

So as your head is moving back and forth, your brain is twisting and turning and contorting, and the tissue is getting stretched.  所以当头部前后晃动时，脑部在旋转、扭曲，部分组织会被拉抻。

And so most experts, I think, would agree that 我认为绝大多数专家都会同意这样一个观点，

concussion¹⁰ is not likely to be something that's happening on this outer surface of the brain, 脑震荡可能不是发生在脑部的外部边缘，

but rather it's something that's much deeper towards the center of the brain. 而是发生在脑部的深处，接近脑部中央的位置。

1 dynamics   

n.力学，动力学，动力，原动力；动态

参考例句：

• In order to succeed,you must master complicated knowledge of dynamics.要取得胜利，你必须掌握很复杂的动力学知识。
• Dynamics is a discipline that cannot be mastered without extensive practice.动力学是一门不做大量习题就不能掌握的学科。

2 skull   

n.头骨；颅骨

参考例句：

• The skull bones fuse between the ages of fifteen and twenty-five.头骨在15至25岁之间长合。
• He fell out of the window and cracked his skull.他从窗子摔了出去，跌裂了颅骨。

3 forth   

adv.向前；向外，往外

参考例句：

• The wind moved the trees gently back and forth.风吹得树轻轻地来回摇晃。
• He gave forth a series of works in rapid succession.他很快连续发表了一系列的作品。

4 vault   

n.拱形圆顶，地窖，地下室

参考例句：

• The vault of this cathedral is very high.这座天主教堂的拱顶非常高。
• The old patrician was buried in the family vault.这位老贵族埋在家族的墓地里。

5 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

6 cerebral   

adj.脑的，大脑的；有智力的，理智型的

参考例句：

• Your left cerebral hemisphere controls the right-hand side of your body.你的左半脑控制身体的右半身。
• He is a precise,methodical,cerebral man who carefully chooses his words.他是一个一丝不苟、有条理和理智的人，措辞谨慎。

7 spinal   

adj.针的，尖刺的，尖刺状突起的；adj.脊骨的，脊髓的

参考例句：

• After three days in Japan,the spinal column becomes extraordinarily flexible.在日本三天，就已经使脊椎骨变得富有弹性了。
• Your spinal column is made up of 24 movable vertebrae.你的脊柱由24个活动的脊椎骨构成。

8 rigid   

adj.严格的，死板的；刚硬的，僵硬的

参考例句：

• She became as rigid as adamant.她变得如顽石般的固执。
• The examination was so rigid that nearly all aspirants were ruled out.考试很严，几乎所有的考生都被淘汰了。

9 jello   

n.凝胶物，果冻

参考例句：

• We have ice cream,pie,cake or jello.我们要冰淇淋、馅饼、蛋糕或是果冻。
• She likes jello very much.她很喜欢吃果冻。

10 concussion   

n.脑震荡；震动

参考例句：

• He was carried off the field with slight concussion.他因轻微脑震荡给抬离了现场。
• She suffers from brain concussion.她得了脑震荡。