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生過，你到樹林中散步，四處溜達了幾個小時候，你想找回停車的路，而你發現你基本是在轉圈。不過，這種事情并非只發生在你身上，因為科學家們發現，在沒有可見標志物或者沒有太陽提供線索的時候，迷失的人們不會走直線。

    在很多虛構的小說中，一直都有"迷失的旅行者繞圈走"的說法。因此科學家們決定驗證這個傳說。他們把六個人放到德國的一個森林中，告訴他們嘗試直著走。科學家們用GPS（全球定位系統）來監測受試者們的行走過程。

    在陰天的時候，這些"漫游者"確實繞圈走，但是他們并非一直繞著一個方向走，他們而是隨機地左右偏離，重復地穿過他們走過的路。但是當受試者可以看到太陽 的時候，他們幾乎能保持走直線。當志愿者們被置于撒哈拉沙漠中的時候，發生了同樣的結果，這項研究結果發表在《當代生物學》（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，請不要依靠你的感覺給你指方向，還是找個指南針吧！