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Take a series of still, sequential images. Let's look at them one by one. Faster.
有一串静态的，连续的图画。我们一张一张地看。加快。
Now, let's remove the gaps, go faster still.
现在我们把间隔去掉，加快。
Wait for it ... Bam! Motion! Why is that?
等等...瞧！动态图像！为什么会这样呢？
Intellectually, we know we're just looking at a series of still images, but when we see them change fast enough,
其实，我们知道我们只是在看一系列的静止图片，但是当它们更换地足够快时，
they produce the optical illusion of appearing as a single, persistent image that's gradually changing form and position.
它们产生一种错视，貌似只有一张图片上有渐渐变化着的形状和姿势。
This effect is the basis for all motion picture technology,
这种效果是动画技术的基础，
from our LED screens of today to their 20th-century cathode ray forebearers,
从如今使用的发光二极管屏幕到它的“祖先”：20世纪阴极射线，
from cinematic film projection to the novelty toy, even, it's been suggested,
从电影胶片放映到一种新奇玩具，甚至，有人提出，
all the way back to the Stone Age when humans began painting on cave walls.
一直追溯到石器时代，从人类开始在洞壁上画图开始。
This phenomenon of perceiving apparent motion in successive images
这种在连续的图片中感觉到动感的奇特现象，
is due to a characteristic of human perception historically referred to as "persistence of vision."
是因为人们的感知能力的特点，在历史上被称为“视觉暂留”。
The term is attributed to the English-Swiss physicist Peter Mark Roget,
这个术语归因于英裔瑞士物理学家彼得·马克·罗杰特，
who, in the early 19th century, used it to describe a particular defect of the eye
在19世纪早期，用这个术语描述眼睛的一种缺陷，
that resulted in a moving object appearing to be still when it reached a certain speed.
造成当一个移动的物体达到一定的速度时，它看上去像静止的。
Not long after, the term was applied to describe the opposite, the apparent motion of still images,
此后不久，这个术语被用来描述恰恰相反的现象：静止的图像看似在运动。
by Belgian physicist Joseph Plateau, inventor of the phenakistoscope.
比利时物理学家约瑟夫·普拉托，费纳奇镜的发明者，运用了这个术语。
He defined persistence of vision as the result of successive afterimages, which were retained and then combined in the retina,
他把“视觉暂留”定义为连续的残像，在视网膜中被保留并合并，
making us believe that what we were seeing is a single object in motion.
使我们认为我们所看到的是一个动态物体。
This explanation was widely accepted in the decades to follow and up through the turn of the 20th century,
这个解释在接下来的几十年中被广泛接受，一直到十九和二十世纪之交，
when some began to question what was physiologically going on.
有些人开始质疑从生理学角度这到底是什么现象。
In 1912, German psychologist Max Wertheimer outlined the basic primary stages of apparent motion using simple optical illusions.
1912年，德国心理学家马克思·韦特海默用简单的错视概述了看似运动的物体的基本的阶段。
These experiments led him to conclude the phenomenon was due to processes which lie behind the retina.
这些实验使他断定，这一现象是因为视网膜后面的一系列过程。
In 1915, Hugo Münsterberg, a German-American pioneer in applied psychology,
在1915年，雨果·芒斯特伯格，一名应用心理学先驱的德裔美国人，
also suggested that the apparent motion of successive images is not due to their being retained in the eye,
也提议连续的图像表面上的运动并不是因为图像被保留在眼睛中，
but is superadded by the action of the mind.
而是大脑促成的。
In the century to follow, experiments by physiologists have pretty much confirmed their conclusions.
在接下来的一个世纪中，生理学家的多次实验也证实了他们的结论。
As it relates to the illusion of motion pictures,
这与动态图画的错觉有关，
persistence of vision has less to do with vision itself than how it's interpreted in the brain.
所以视觉暂留和视觉本身没有很多关联，而是大脑是如何分析图像的。
Research has shown that different aspects of what the eye sees, like form, color, depth, and motion,
研究表明，眼睛从不同角度所观察到的物体，比如形状，颜色，深度和动感，
are transmitted to different areas of the visual cortex via different pathways from the retina.
通过视网膜中不同的途径，被传输到视觉皮层的不同部位。
It's the continuous interaction of various computations in the visual cortex
视觉皮层中不同部位的不同的感应之间持续互动，
that stitch those different aspects together and culminate in the perception.
使这些不同角度看到的东西结合在一起，促成了视觉的感受。
Our brains are constantly working, synchronizing what we see,
我们的大脑在不断地工作，同步我们所看到的，
hear, smell, and touch into meaningful experience in the moment-to-moment flow of the present.
听到的，闻到的和触摸到的，把流动的瞬间结合成有意义的体验。
So, in order to create the illusion of motion in successive images,
为了创造连续性图像的动感的错觉，
we need to get the timing of our intervals close to the speed at which our brains process the present.
我们需要使间隔时间接近我们大脑领会现状的速度。
So, how fast is the present happening according to our brains?
我们的大脑识别现状的速度到底有多快呢？
Well, we can get an idea by measuring how fast the images need to be changing for the illusion to work.
我们可以通过测量图片需要以多快的速度切换，才会有动感的效果。
Let's see if we can figure it out by repeating our experiment.
让我们重复我们的实验，解开这个难题。
Here's the sequence presented at a rate of one frame per two seconds with one second of black in between.
这一系列图片是以每两秒种一个图片的速度，再加上一秒钟的间隔。
At this rate of change, with the blank space separating the images, there's no real motion perceptible.
以这个速度，还有图像之间的间隔，我们无法感觉到动感。
As we lessen the duration of blank space, a slight change in position becomes more apparent,
当我们渐渐减少间隔时间时，图片中人物的位置的变化更加明显了，
and you start to get an inkling of a sense of motion between the disparate frames.
然后你开始慢慢感觉到在图像中有动态效果了。
One frame per second. Two frames per second. Four frames per second.
每一秒钟一个图像，每秒两个图像，每秒四个图像。
Now we're starting to get a feeling of motion, but it's really not very smooth.
现在我们有动态的感觉了，但是不是非常流畅。
We're still aware of the fact that we're looking at separate images.
我们还能意识到我们在看独立的图像。
Let's speed up. Eight frames per second. 12 frames per second. It looks like we're about there.
让我们加速。每秒8个图像，每秒12个图像。看上去差不多了。
At 24 frames per second, the motion looks even smoother. This is standard full speed.
以每秒24个图像的速度，感觉更加流畅了。这是标准的全速。
So, the point at which we lose awareness of the intervals
当我们意识不到间隔，
and begin to see apparent motion seems to kick in at around eight to 12 frames per second.
并且开始感觉到动感时，图像速度大约在每秒8-12个图像。
This is in the neighborhood of what science has determined to be the general threshold of our awareness of seeing separate images.
这个速度就是用科学测量出的我们观察独立图像的意识的速度。
Generally speaking, we being to lose that awareness at intervals of around 100 milliseconds per image,
一般来说，当我们失去那种意识时，速度大约是每张图像100毫秒，
which is equal to a frame rate of around ten frames per second.
约等于每秒10个图像的帧速率。
As the frame rate increases, we lose awareness of the intervals completely and are all the more convinced of the reality of the illusion.
当帧速率增加时，我们就彻底失去了图片之间有间隔的意识，也就更加确信了幻觉的真实性。
