Maybe it's happened to you. You go for a walk in the woods and, after wandering around for a few hours trying to find your way back to the car, you realize that you've basically been walking in circles. Well, you're not alone. Because scientists have found that, in the absence of visible landmarks or cues from the sun, people who are lost can't walk a straight line.

    The "disoriented traveler walking in circles" is faithfully trotted out in many fictional works. So scientists decided to put the tale to the test. They plopped six people into a German forest and told them to try to walk straight. And they monitored their subjects' progress by GPS.

    When the day was cloudy, the wanderers indeed walked in circles, but not by turning consistently in one direction. Instead they veered randomly left and right, repeatedly crossing their own paths. But when the subjects could see the sun, they maintained an almost straight course. And the same was true when volunteers were dropped into the Sahara Desert during the day and at night, results published in the journal Current Biology.

    So if you want to walk the straight and narrow, especially after dark, don't count on your conscience to guide you. Get a compass.

    迷失方向后我們繞圈走

    可能這種情況在你身上發(fā)生過(guò)，你到樹(shù)林中散步，四處溜達(dá)了幾個(gè)小時(shí)候，你想找回停車(chē)的路，而你發(fā)現(xiàn)你基本是在轉(zhuǎn)圈。不過(guò)，這種事情并非只發(fā)生在你身上，因?yàn)榭茖W(xué)家們發(fā)現(xiàn)，在沒(méi)有可見(jiàn)標(biāo)志物或者沒(méi)有太陽(yáng)提供線索的時(shí)候，迷失的人們不會(huì)走直線。

    在很多虛構(gòu)的小說(shuō)中，一直都有"迷失的旅行者繞圈走"的說(shuō)法。因此科學(xué)家們決定驗(yàn)證這個(gè)傳說(shuō)。他們把六個(gè)人放到德國(guó)的一個(gè)森林中，告訴他們嘗試直著走�？茖W(xué)家們用GPS（全球定位系統(tǒng)）來(lái)監(jiān)測(cè)受試者們的行走過(guò)程。

    在陰天的時(shí)候，這些"漫游者"確實(shí)繞圈走，但是他們并非一直繞著一個(gè)方向走，他們而是隨機(jī)地左右偏離，重復(fù)地穿過(guò)他們走過(guò)的路。但是當(dāng)受試者可以看到太陽(yáng) 的時(shí)候，他們幾乎能保持走直線。當(dāng)志愿者們被置于撒哈拉沙漠中的時(shí)候，發(fā)生了同樣的結(jié)果，這項(xiàng)研究結(jié)果發(fā)表在《當(dāng)代生物學(xué)》（Current Biology）雜志上。

    因此如果你不想繞圈子走的話，尤其是黑天以后，請(qǐng)不要依靠你的感覺(jué)給你指方向，還是找個(gè)指南針吧！