爲什麼你會怕蛇,怕蜘蛛大綱

If the thought of a snake slithering around your feet or a spider walking up your arm sends shivers down your spine, despite never having come into contact with one in real life, then it could be your genes that are to blame. Over the last few decades there has been much debate between scientists about whether these phobias are innate or are learned during childhood.

如果一想到蛇在你的腳邊遊動或是蜘蛛在你的胳膊上爬來爬去你就感到脊椎發涼（儘管在現實生活中你從未接觸過），那這可能是基因作祟。過去幾十年，科學家一直在爭論：這些恐懼症究竟是天生的還是在兒童時期通過學習得到的？

But a new study has discovered that it is in fact hereditary, as babies at only six months old (long before they have had a chance to learn about the dangers of spiders and snakes) show signs of stress when they see these creatures.

但一項新研究發現，事實上這是遺傳得來的，6個月大的寶寶（早在他們有機會了解蛇和蜘蛛非常危險之前）在看到蛇或者蜘蛛時都會表現出壓力。

It is estimated that the UK alone there are over 10 million people living with phobias, and ophidiophobia (fear of snakes) and arachnophobia (fear of spiders) always top the list of the most common concerns, according to a YouGov survey.

據一項YouGov調查表示，據估計，僅英國就有超過1000萬人患有恐懼症，恐蛇症和恐蜘蛛症總是位列恐懼症的榜首。

Now a team at the Max Planck Institute for Human Cognitive and Brain Sciences in Sweden have concluded that it isn’t because we are taught to fear them after birth. In the trial, they showed a group of babies images of spiders and snakes alongside flowers and fish - all the same size and in the same colour.

位於瑞典的馬克斯•普朗克人類認知和腦科學研究院的一個團隊得出結論：對蛇和蜘蛛的恐懼並不是因爲出生後別人教會我們的。在實驗中，研究人員給一羣寶寶看蜘蛛、蛇以及鮮花與魚的圖片——都是同樣的尺寸、同樣的顏色。

When the child’s gaze rested upon the snake or spider, rather than the other animals, their pupils enlarged significantly - a classic physiological signpost that a human is experiencing internal stress.

當寶寶的視線落在蛇或蜘蛛而非其它動物圖片上時，他們的瞳孔明顯放大——這是人類正在經歷內在壓力的典型生理指標。

Stefanie Hoehl, lead investigator, said: “In constant light conditions this change in size of the pupils is an important signal for the activation of the noradrenergic system in the brain, which is responsible for stress reactions. Accordingly, even the youngest babies seem to be stressed by these groups of animals.”

首席研究員斯蒂芬妮•赫厄說道：“在不變的光照條件下，瞳孔大小的變化是大腦去甲腎上腺素被激活的重要信號，去甲腎上腺素是造成壓力反應的原因。因此，即使是剛出生的寶寶也會因爲這兩種動物而感到壓力。”

And it would be hard to argue that as a relative newborn, who is immobile, that they had had a chance to learn to be scared of spiders or snakes. Instead they argue that this is an evolutionary development, and similar to primates, mechanisms in the human brain have had to develop to react very quickly to these potentially dangerous threats.

而我們都很清楚，作爲一個動不了的新生兒，他們並沒有機會去學會害怕蜘蛛或蛇。所以有人認爲這是一個進化的發展，與靈長類動物相似，人類的大腦機制不得不發展，以快速應對這些潛在的危險。