人為啥會暈車？因為大腦以為我們中毒了

Traveling makes us feel sick because modern transport tricks the brain into thinking we have been poisoned, a neuroscientist has said.

一位神經(jīng)系統(tǒng)科學(xué)家表示，現(xiàn)代交通工具會誘導(dǎo)大腦認為我們已經(jīng)中毒，所以旅行常常使我們感到不舒服。

Being in a car, train, boat or plane causes conflicting signals in the brain which trigger a reaction similar to that which occurs when someone is poisoned.

乘坐汽車、火車、船舶或飛機的體驗會在大腦中形成相互矛盾的信號，這會引發(fā)和人們中毒時相似的反應(yīng)。

Dr Dean Burnett, of Cardiff University, said the feeling of nausea is caused because the brain thinks the body needs to remove a toxin through vomiting.

卡迪夫大學(xué)的迪安•伯內(nèi)特博士稱，大腦認為人體需要通過嘔吐排毒，于是便造成了這種惡心感。

But in fact, the 'poisoning' effect is caused by the mixed messages from the muscles – which tell the brain the body is motionless – and the ears, which sense movement.

但事實上，這種“中毒”效應(yīng)是由肌肉中的混合信息所引發(fā)的，肌肉向大腦傳達身體靜止的信息，而耳朵卻察覺到身體在運動。

Speaking on the US radio show Fresh Air, Dr Burnett said that the body had not yet evolved to cope with the sensation of being in vehicles, where the body is being moved without performing movements itself.

伯內(nèi)特博士在美國廣播電臺節(jié)目《新鮮空氣》中表示，在交通工具中人們的身體在被移動，而本身卻未執(zhí)行任何行動，人體還未進化到能夠適應(yīng)這種感覺。

He said: 'When we're in a vehicle like a car or a train or a ship especially, you're not actually physically moving... Your muscles are saying 'we are stationary'.

他說：“當(dāng)我們乘坐尤其是汽車、火車或是輪船這樣的交通工具時，你的身體事實上沒有在運動，因此你的肌肉也認為‘我們是靜止的’。”

'If you are sitting in a ship, you're looking at a static environment, so there's no information for the eyes to say 'we are moving'.

“如果你坐在船上，你是看著一個靜態(tài)的環(huán)境，因此并沒有傳遞給眼睛‘我們正在運動’的信息。

'But the fluids in your ears, they obey the laws of physics. And they are sort of rocking around and sloshing because you are actually moving.

“但是你耳朵里的液體遵循物理定律，你確實在移動，因此它們四處搖擺、晃動。

'So what's happening there is the brain's getting mixed messages. It's getting signals from the muscles and the eyes saying "we are still" and signals from the balance sensors saying 'we're in motion'. Both of these cannot be correct. There's a sensory mismatch there.

“所以問題就是大腦得到了混合信息。肌肉和眼睛告訴它‘我們是靜止的’，而從平衡感知器官傳來的信號又說‘我們在運動’。這兩者不可能同時正確，所以知覺就不相匹配。

'And in evolutionary terms, the only thing that can cause a sensory mismatch like that is a neurotoxin or poison. So the brain thinks, essentially, it's been being poisoned.

“從進化角度來看，唯一能夠引起感知矛盾的就是神經(jīng)毒素或中毒，因此大腦判斷其根源在于中毒了。

'When it's been poisoned, the first thing it does is get rid of the poison, aka throwing up.'

“當(dāng)中毒的時候，首先要做的就是排毒，也就是嘔吐。”

He explained that reading in a car made the sensation of travel sickness worse, because the eyes were focused on a small, static space and gave the brain no information to explain that the body was moving.

他進一步解釋，在車上閱讀會惡化暈車的癥狀，因為眼睛始終盯著一塊小而靜止的空間，讓大腦無從解釋為什么感到身體正在移動。

The feeling of sickness could be relieved by looking out of a car window because this showed the brain movement was taking place.

看車窗外卻能夠緩解暈車的感覺，因為這告訴大腦人體正在運動當(dāng)中。

'You can see the passage and movement itself, so that balances the system,' he said.

他說：“你可以親眼目睹過道以及移動本身，這也就讓系統(tǒng)得到了平衡。”

'The brain's going: 'Oh, look, things moving - I must be moving' - and then sort of calms down the sickness response.'

“大腦這樣思考：‘噢，看，物體在運動，我也一定在運動’——這也就在某種程度上緩解了暈車的反應(yīng)。”

Dr Burnett, who was discussing his new book 'Idiot Brain: what your head is really up to', said brain systems became more refined and efficient as people aged but that children were more susceptible to travel sickness because their brains were still developing.

伯內(nèi)特博士在新書《愚蠢的大腦：你的頭究竟怎么了》中說道，隨著人們歲數(shù)的增大，腦部系統(tǒng)變得越來越精煉和高效，而孩子們更容易暈車，因為他們的大腦仍在發(fā)育當(dāng)中。

He said there was no clear reason why some people suffered from travel sickness more than others, calling it a 'quirk of development'.

他表示，現(xiàn)在還無法清楚地解釋為什么有些人比別人更容易暈車，他將其命名為“發(fā)育中的怪異現(xiàn)象”。

But he said there were several other aspects of modern life with which the brain had not yet evolved to cope.

但他同時聲稱，大腦進化至今還未能適應(yīng)現(xiàn)代生活中的好多其他方面。

For example, jet-lag was the brain's response to being disorientated by being moved between time zones with different levels of daylight, he said.

他說，舉例來說，時差綜合癥是人體穿梭于不同時區(qū)不同白晝時，大腦因感到迷亂而產(chǎn)生的反應(yīng)。