听力文摘：脑震荡从何而来

If you follow football, hockey, soccer, or boxing, then you know that athletes in these and other contact sports are at constant risk for a concussion¹. Every season several football players miss a number of games after absorbing vicious blows to the head.

如果你喜欢橄榄球、橄榄球、足球或是拳击运动，那么你就会很清楚这些以及其他接触性运动中的运动员常处于脑震荡的危险境地。每个赛季都有数名橄榄球运动员由于头部遭受剧烈冲击而缺席接下来的一系列赛事。

A concussion is a blow to the head that can result in temporary confusion, amnesia², nausea³, dizziness, blurred⁴ vision, and loss of consciousness.

脑震荡是头部受到撞击而导致的，可能造成暂时性思维混乱，失忆，呕吐，眩晕，视觉模糊以及失去意识。

Although a single concussion does not appear to result in structural⁵ brain damage or swelling⁶ of the brain, repeated concussions⁷ can cause both.

尽管一次脑震荡不会导致大脑结构性损伤或导致脑水肿，但是数次脑震荡可能引起上述两种情况同时出现。

Concussions are caused in one of two ways: either by the head hitting a hard surface, or by the head spinning suddenly. Take, for example, a common incident during a football game. The quarterback is hit, falls backwards⁸, and bangs his head on the turf.

造成脑震荡的原因不外乎是这两种中的一种：头部撞到硬物，或者头部突然旋转。以橄榄球赛比较普遍的事件为例，四分卫触地得分，朝后方倒下，其头部就会猛烈撞击到草坪上。

Although his skull⁹ stops suddenly upon impact, his brain, floating in cerebral¹⁰ fluid, keeps moving and hits the skull. Similarly, when a boxer¹¹ gets hit in the head with a right hook, his head twists violently. The skull stops moving, but the brain keeps shaking for a few moments and may brush the skull.

尽管他的头骨在受到冲击时瞬间会保持不动，但是他大脑内的脑脊液仍然在晃动并不断撞击头骨。同样的，当一名拳击手头部受到一记右勾拳时，他的脑袋瞬间剧烈扭转。头骨停止移动，但是脑浆却还会震动一会儿，并有可能摩擦到头骨。

The result is a chemical imbalance in the brain. All the neurotransmitters in the damaged area fire simultaneously¹², causing an overload¹³ of chemicals that impair¹⁴ receptors involved in learning and memory. The flood of chemicals also constricts¹⁵ arteries¹⁶, making it difficult for the damaged cells to get the nutrients¹⁷ they need to recover.

结果是脑部化学失衡。所有受损区域的神经传递素同时作用，造成脑内化学物质超负荷运转，从而损坏学习与记忆的神经元。化学物质过多也会引起动脉收缩，导致大脑受损细胞难以吸收到利于复原的营养物质。

Because the brain can take as long as several weeks to recover from a concussion, it's a good idea to take a break from contact sports if you've had one.

由于脑部需要长达数周的时间来恢复脑震荡带来的损伤，如果你脑部受到撞击最好还是休息一段时间再继续参加此类接触性运动。

1 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。

2 amnesia   

n.健忘症，健忘

参考例句：

• People suffering from amnesia don't forget their general knowledge of objects.患健忘症的人不会忘记关于物体的一些基本知识。
• Chinese medicine experts developed a way to treat amnesia using marine materials.中国医学专家研制出用海洋物质治疗遗忘症的方法。

3 nausea   

n.作呕，恶心；极端的憎恶(或厌恶)

参考例句：

• Early pregnancy is often accompanied by nausea.怀孕期常有恶心的现象。
• He experienced nausea after eating octopus.吃了章鱼后他感到恶心。

4 blurred   

v.（使）变模糊( blur的过去式和过去分词 )；（使）难以区分；模模糊糊；迷离

参考例句：

• She suffered from dizziness and blurred vision. 她饱受头晕目眩之苦。
• Their lazy, blurred voices fell pleasantly on his ears. 他们那种慢吞吞、含糊不清的声音在他听起来却很悦耳。 来自《简明英汉词典》

5 structural   

adj.构造的，组织的，建筑（用）的

参考例句：

• The storm caused no structural damage.风暴没有造成建筑结构方面的破坏。
• The North American continent is made up of three great structural entities.北美大陆是由三个构造单元组成的。

6 swelling   

n.肿胀

参考例句：

• Use ice to reduce the swelling. 用冰敷消肿。
• There is a marked swelling of the lymph nodes. 淋巴结处有明显的肿块。

7 concussions   

n.震荡( concussion的名词复数 )；脑震荡；冲击；震动

参考例句：

• People who have concussions often trouble thinking or remembering. 患脑震荡的人通常存在思考和记忆障碍。 来自互联网
• Concussions also make a person feel very tired or angry. 脑震荡也会使人感觉疲倦或愤怒。 来自互联网

8 backwards   

adv.往回地，向原处，倒，相反，前后倒置地

参考例句：

• He turned on the light and began to pace backwards and forwards.他打开电灯并开始走来走去。
• All the girls fell over backwards to get the party ready.姑娘们迫不及待地为聚会做准备。

9 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。

10 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。

11 boxer   

n.制箱者，拳击手

参考例句：

• The boxer gave his opponent a punch on the nose.这个拳击手朝他对手的鼻子上猛击一拳。
• He moved lightly on his toes like a boxer.他像拳击手一样踮着脚轻盈移动。

12 simultaneously   

adv.同时发生地，同时进行地

参考例句：

• The radar beam can track a number of targets almost simultaneously.雷达波几乎可以同时追着多个目标。
• The Windows allow a computer user to execute multiple programs simultaneously.Windows允许计算机用户同时运行多个程序。

13 overload   

vt.使超载；n.超载

参考例句：

• Don't overload the boat or it will sink.别超载，否则船会沉。
• Large meals overload the digestive system.吃得太饱会加重消化系统的负担。

14 impair   

v.损害，损伤；削弱，减少

参考例句：

• Loud noise can impair your hearing.巨大的噪音有损听觉。
• It can not impair the intellectual vigor of the young.这不能磨灭青年人思想活力。

15 constricts   

压缩，压紧，使收缩( constrict的名词复数 )

参考例句：

• The tumour constricts the nerves. 肿瘤压迫神经。
• Fat constricts the blood vessels, making your circulation bad. 脂肪压缩血管，造成你的血液循环不畅。

16 arteries   

n.动脉( artery的名词复数 )；干线，要道

参考例句：

• Even grafting new blood vessels in place of the diseased coronary arteries has been tried. 甚至移植新血管代替不健康的冠状动脉的方法都已经试过。 来自《简明英汉词典》
• This is the place where the three main arteries of West London traffic met. 这就是伦敦西部三条主要交通干线的交汇处。 来自《简明英汉词典》

17 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》