Everyone loves a good optical illusion.
每個人都喜歡好的視覺錯覺。
There are ones that play with your perception of color, or look like they're swirling even though they're still.
有一些視覺錯覺會影響你對顏色的感知,或者看起來它們在打轉,即使它們靜止不動。
And how about the Muller-Lyer illusion? It's named after the German sociologist,
繆勒-萊爾錯覺呢?它是以德國社會學家的名字命名的,
Franz Carl Müller-Lyer, who came up the image in 1889.
弗蘭茲·卡爾·穆勒-萊爾在1889年創作了這幅畫。
Basically, it's a couple of arrow-like figures. How do you think the lines compare to each other?
基本上,它是一對箭頭狀的圖形。你認為這兩條線有什么不一樣?
Even if you've seen this illusion before, chances are the lines look like they're slightly different lengths—
即使你以前見過這種錯覺,可能它們的長度看起來略有不同。
but they're actually the same. But not everyone falls for this trick.
但它們其實是一樣的。但并不是每個人都會上當。
A lot of it might actually have to do with where you're from and what you're used to seeing,
大多數時候與你來自哪里以及你曾經看過的東西有關,
because optical illusions are designed to trick your brain.
因為視覺錯覺是為了欺騙你的大腦。
The brain's visual cortex processes everything your eyes see,
大腦的視覺皮層處理眼睛看到的一切,
starting with two-dimensional images from your retinas, and figuring out depth somehow.
它始于視網膜上的二維圖像,并以某種方式計算深度。
We think the brain calculates depth using binocular disparity—
我們認為大腦利用雙眼視差來計算深度——
the difference between what your right eye sees and what your left eye sees—
右眼和左眼的區別——
along with other cues, like the size of different things and angles in a space.
以及其它提示,比如不同事物的大小和在空間的角度。
Psychologists think the Müller-Lyer illusion hinges on those other visual cues that hint at three dimensions,
心理學家認為,繆勒-萊爾錯覺取決于那些暗示三維空間的視覺提示,
and works best on brains that are used to seeing a bunch of right angles.
并且對那些習慣看到很多直角的大腦來說效果最好。
Many of us live and work in spaces that are chock full of right angles,
我們中的大多數人在充滿直角的空間生活和工作,
so we're used to interpreting depth in boxy rooms.
所以我們習慣于在四四四方方的房間里解讀深度。
If you're standing on one side of a long table, for instance,
如果你站在一張長桌的一側,
you know that the side closest to you is the same size as the opposite.
你知道,最靠近你的那一邊和對邊長度一樣。
But the closer side looks bigger, and the farther side looks smaller.
但是較近的一邊看起來長度更長,而更遠的一邊看起來長度更短。
That's thanks to perspective. The Müller-Lyer illusion plays with our brain's sense of perspective.
這是因為視角的緣故,繆勒-萊爾錯覺與大腦的視角有關。
The arrow-like caps on the ends of each line might trick our brains into interpreting both of them as having some depth.
每行末端都有一個箭頭狀的帽子,這可能會讓我們的大腦誤以為它們都有一定的深度。
So the line with inward-pointing arrow heads is being interpreted as farther away,
所以箭頭朝內的線被解讀為更遠,
and the line with outward-pointing arrow heads is being interpreted as closer.
而箭頭朝外的線被解讀為更近。
Even though our eyes might detect that the lines are the same length, our brains might get confused about the perspective.
盡管我們的眼睛可能會發現線條長度相同,但大腦可能會對視角感到困惑。

You brain might perceive the farther line as smaller, like that far end of a table in a 3D world, and therefore think it's really a longer line.
大腦可能會感知到距離遠的線更短,就像3D世界中桌子的遠端一樣,因此認為這條線實際上會更長。
Not all people are surrounded by so many 90-degree angles, though.
然而,并不是所有的人周圍有這么多90度的角。
And those who aren't seem to be less susceptible to the Müller-Lyer illusion.
周圍沒有那么多90度角的人似乎不太容易受到繆勒-萊爾錯覺的影響。
In the 1960s, a group of researchers led by psychologist Marshall H. Segall set out to test what they called the "carpentered world" hypothesis
20世紀60年代,心理學家馬歇爾·塞格爾(Marshall H. Segall)帶領一組研究人員著手對所謂的“木工世界”假說
and the "experience with two-dimensional representations of reality" hypothesis.
以及“二維現實表征”假說進行測試,
The researchers proposed that some peoples' experience with "carpentered" or box-like spaces and 2D images of 3D spaces,
研究人員提出,一些人的“木制”或者盒狀空間以及3D空間中2D圖片的體驗,
like photographs of rooms, helped the illusion trick their brains.
比如房間里的照片,能夠幫助錯覺。
They collected data from individuals in 17 groups of people around the world,
他們收集了來自世界各地17組人的數據,
showing them sets of two arrow-like lines—one with the caps pointing out, labeled a, and one with the caps pointing in, labeled b.
研究人員向他們展示兩組類似箭頭的線—— 一個是帽朝外,標記為a,另一帽朝內,標記為b。
Then, they gathered data about how much longer line a needs to be than line b before people perceived them as equal.
然后,他們收集了關于人們認為a線和b線相等之前,a線需要比b線長多少的數據。
The greater the difference, the more susceptible the group was to the illusion.
差異越大,這群人越容易受錯覺影響。
The most susceptible group was from Evanston, Illinois in the United States.
最易受影響的群體是美國伊利諾伊州的埃文斯頓。
And the group of Europeans living in Johannesburg, South Africa was pretty susceptible too.
生活在南非約翰內斯堡的歐洲人也很容易受到影響。
On the other hand, societies of agriculturalists and foragers, like the San from the Kalahari Desert or Bete from the Ivory Coast,
另一方面,農學家和覓食者的社會,如喀拉哈里沙漠的圣人或象牙海岸的貝特,
were less tricked by the illusion. And they probably didn't spend as much time in right-angle-filled environments.
更少被錯覺欺騙??赡芩麄冊诔錆M直角的環境中待的時間不長。
Of course, one study isn't definitive proof of a phenomenon.
當然,一項研究并不能證明這一現象。
A different study from 1973 involved one group of Americans and five groups of Zambians.
1973年的另一項研究——一組美國人和五組贊比亞人參與其中——
And a difference was found between Zambians living in rural and urban environments,
發現生活在農村和城市環境中的贊比亞人之間存在差異,
where those living in urban environments were more susceptible to the illusion.
生活在城市環境中的人更容易受到錯覺的影響。
This supported the idea that being tricked by the illusion could involve factors like people's immediate surroundings.
該研究支持了這樣一種觀點,即被錯覺所欺騙的因素中可能涉及像人的周圍環境這樣的因素。
And as psychologists have studied this illusion more,
隨著心理學家對視覺錯覺的研究越來越多,
it seems like how you perceive the lines in the Müller-Lyer illusion is at least partially influenced by what you see all the time,
似乎穆勒-萊爾錯覺中的線長至少部分受到一直所看事物的影響,
because that's what your brain is used to interpreting.
因為那是大腦用來解釋的東西。
Other researchers have tried to look into different cases where visual perception seems to be influenced by your surroundings and culture.
其他研究人員嘗試過將目光轉向另一案例——視覺感知似乎受到周圍環境和文化的影響。
A 2005 study, for instance, found that Japanese and American undergraduates noticed changes in images differently.
例如,2005年的一項研究發現,日本和美國的大學生注意到的圖像變化是不同的。
They were shown pictures of different scenes like an American city,
讓他們看不同場景的照片,比如一座美國城市,
a Japanese city, or something without cultural markers like a generic construction site.
一座日本城市,或者沒有文化標志的事物,比如一般的建筑工地。
And they were given a change blindness task, where they had to pick out small changes between very similar sets of pictures.
他們接受了一項變化盲視任務,必須在非常相似的一組圖片中找出微小的變化。
With American scenery, all participants were generally better at seeing changes that involved prominent objects.
對于美國風景,所有參與者通常更善于看到與突出物體有關的變化。
And with Japanese scenery, all participants were generally better at noticing changes in the background.
對于日本風景,所有參與者通常更善于注意到背景的變化。
But with the neutral scenery, it seemed like cultural differences showed up:
但對于中性風景,似乎出現了文化差異:
Japanese students noticed more contextual changes, and American students noticed more focal object changes.
日本學生注意到更多的是情境變化,美國學生注意到更多的是焦點物體變化。
Citing other studies that tracked participants'eye movements,
研究人員引用其他追蹤參與者的眼球運動的研究,
the researchers proposed that these differences could be because different people pay attention to their surroundings differently.
提出這些差異可能是因為不同人對周圍環境的關注點不同。
Or it could mean that different environments encourage different kinds of interpretation by our eyes and brains.
也可能是因為不同的環境激勵我們的眼睛和大腦做出不同的解釋。
It's important to remember, though, that there might be other factors in play in these perception experiments.
不過,重要的是要記住,在這些感知實驗中可能還有其他因素在起作用。
But if these kinds of studies tell us anything, it's that brains are complicated, and everyone is probably seeing things from a slightly different perspective.
但如果說這些研究告訴我們什么的話,那就是大腦是復雜的,每個人都可能從略微不同的角度看事物。
Thanks for using your eyes and brains to watch this episode of SciShow Psych!
感謝收看本期的心理科學秀!
If you want to learn more about weird phenomena involving the human mind, you can go to youtube.com/scishowpsych and subscribe.
如果你想了解更多有關人類大腦的奇怪現象,可以訪問并訂閱youtube.com/scishowpsych。