有声英文阅读-为什么自己哈痒不觉痒

Why Can't You Tickle¹ Yourself

    Have you ever thought about why people are ticklish²? According to scientists, ticklishness³ is a defense⁴ mechanism⁵ humans developed against bugs⁶, spiders, and other critters that may be touching⁷ our skin. Feeling ticklish is our built-in response to predators⁸ or threats, and combines the sensations of touch and pain.

    The part of the brain that is associated with tickling⁹ is the cerebellum. It monitors our movements, but ignores movements not perceived as a threat. For example, we do not notice our vocal¹⁰ chords moving when we speak, but we may jump if someone touches us on the shoulder. This selective perception is probably the reason why we cannot tickle ourselves.

    We only feel ticklish if we detect a sense of invasion or attack. If we try to tickle ourselves, our brains anticipate this "attack" and prevent us from feeling panicked. Strangely enough, even if a person knows that they are about to be tickled¹¹, the fear of being touched may cause the same "ticklish" reaction. Some people laugh even before being tickled.
   
    A scientific study was recently done in England to determine whether or not people can tickle themselves. Volunteers were attached to a brain-scanning device and were tickled on their palms with a piece of soft foam¹² . The participants' brain scans were monitored while they were being tickled, and when they tickled themselves. It was found that during self-tickling, the cerebellum alerted another area of the brain about what to expect, so the ticklish feeling was diminished.
 
    Researchers did find a way, however, for people to tickle themselves. When volunteers activated¹³ a robot by remote control to tickle them after a short delay, the volunteers felt as if someone else were tickling them. It seems that the cerebellum sends a signal to disregard the forthcoming movement, then moves on to other things. Your brain "forgets" that you are tickling yourself—even with a delay as short as a fifth of a second. So it is possible to tickle yourself—but only by remote control. What will science discover next?

为什么自己哈痒不觉痒？

    你有没有想过人为什么会怕痒？根据科学家的观点，怕痒是一种防御机制，是人类把它培养来对付那些可能接触我们皮肤的虫子、蜘蛛或其他生物。怕痒是我们对侵扰者或威胁产生的内在反应，它使触觉和痛觉结合起来了。

    脑部与怕痒有关的部位是小脑。小脑监控我们的一举一动，但对其认为不具威胁性的活动，往往会忽视。举例来说，我们说话时不会察觉声带的振动，但是如有人触摸我们的肩膀时，我们可能会吓一跳。这种选择性的知觉或许就是我们无法自已哈痒的原因。

    我们只会在察觉受到侵犯或攻击时才会觉得痒。如果试着替自己哈痒，脑部会自动预感到这种“攻击”从而使我们感觉不到惊吓。奇怪的是，即使有人知道他要被哈痒了，担心被人触摸，也会引起同样“怕痒”的反应。有些人甚至还没被哈到痒就先笑了。

    英格兰近期做了一项关于人是否可以替自己哈痒的科学研究。自愿受测者接上脑部扫描仪，并用一块软泡沫绵给手掌哈痒。参与者在被哈痒和自行哈痒时，脑部扫描状况都受到监视。结果发现，在自行哈痒的过程中，小脑会向脑部的另一部位发出警告，使其预先防范，所以痒的感觉就消失了。

    然而，研究人员也发现了可以替自己哈痒的方法。自愿者用遥控器操纵机器人，延迟片刻之后再让机器人为自己哈痒，自愿者就会觉得好像是别人在给他们哈痒。看来小脑在发出信号忽视即将到来的动作，然后将注意力转移到其他事物上。尽管只有零点二秒的时间差，脑部就会“忘记”你在替自己哈痒。所以自己给自己哈痒仍有可能，只不过需要依靠遥控器。谁知道接下来科学还会有什么新发现呢？

1 tickle   

v.搔痒，胳肢；使高兴；发痒；n.搔痒，发痒

参考例句：

• Wilson was feeling restless. There was a tickle in his throat.威尔逊只觉得心神不定。嗓子眼里有些发痒。
• I am tickle pink at the news.听到这消息我高兴得要命。

2 ticklish   

adj.怕痒的；问题棘手的；adv.怕痒地；n.怕痒，小心处理

参考例句：

• This massage method is not recommended for anyone who is very ticklish.这种按摩法不推荐给怕痒的人使用。
• The news is quite ticklish to the ear,这消息听起来使人觉得有些难办。

3 ticklishness   

n.怕痒，小心处理

参考例句：

4 defense   

n.防御，保卫；[pl.]防务工事；辩护，答辩

参考例句：

• The accused has the right to defense.被告人有权获得辩护。
• The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。

5 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

6 bugs   

adj.疯狂的，发疯的n.窃听器( bug的名词复数 )；病菌；虫子；[计算机]（制作软件程序所产生的意料不到的）错误

参考例句：

• All programs have bugs and need endless refinement. 所有的程序都有漏洞，都需要不断改进。 来自《简明英汉词典》
• The sacks of rice were swarming with bugs. 一袋袋的米里长满了虫子。 来自《简明英汉词典》

7 touching   

adj.动人的，使人感伤的

参考例句：

• It was a touching sight.这是一幅动人的景象。
• His letter was touching.他的信很感人。

8 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》

9 tickling   

反馈，回授，自旋挠痒法

参考例句：

• Was It'spring tickling her senses? 是不是春意撩人呢？
• Its origin is in tickling and rough-and-tumble play, he says. 他说，笑的起源来自于挠痒痒以及杂乱无章的游戏。

10 vocal   

adj.直言不讳的；嗓音的；n.[pl.]声乐节目

参考例句：

• The tongue is a vocal organ.舌头是一个发音器官。
• Public opinion at last became vocal.终于舆论哗然。

11 tickled   

（使）发痒( tickle的过去式和过去分词 )； （使）愉快，逗乐

参考例句：

• We were tickled pink to see our friends on television. 在电视中看到我们的一些朋友，我们高兴极了。
• I tickled the baby's feet and made her laugh. 我胳肢孩子的脚，使她发笑。

12 foam   

v./n.泡沫，起泡沫

参考例句：

• The glass of beer was mostly foam.这杯啤酒大部分是泡沫。
• The surface of the water is full of foam.水面都是泡沫。

13 activated   

adj. 激活的 动词activate的过去式和过去分词

参考例句：

• The canister is filled with activated charcoal.蒸气回收罐中充满了活性炭。