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visual perception made simple.
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Yeah, our eyes are like windows to the world.
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We observe the smallest fluff on the rug and the farthest stars in the sky.
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At a stadium, we tracked the flight path of a soccer ball and perceived millions of different gradations of car.
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But how exactly does that work?
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The essential prerequisite is light.
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When it enters the eye, it first passes through the lens and the vitreous body before reaching the retina.
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There, it encounters millions of tiny photo receptor cells with different jobs.
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Mhm.
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Three types of cone cells, for instance, react to different wavelengths of light.
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That's why we can see a variety of colors.
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However, in order to do their job, the cones need enough light.
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At night, only the rods are active.
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They help us to perceive shades of gray and light dark contrasts that keeps us from walking into a lamppost in the dark.
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But all cats look gray at night.
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The rods and cones react to the energy of the incoming light and translated into a language.
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The brain understands electric signals.
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Other cells down the line process these signals further.
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Some of those cells heightened light, dark contrasts.
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Others are in charge of sharpening the image.
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Nearly 130 million rods and cones are distributed between about one million nerve cells, and each of them transmits a different bit of information that includes tasks related to shape, color, motion, direction and much more.
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The bundle tales of the nerve cells form the optic nerve.
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It's like a cable leading from the retina straight into the brain that transmits the signal almost instantaneously important for things like driving a car.
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Because we have two eyes, we also have to optic nerves.
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These cross paths and travel from the inter brain through a kind of substation straight into the visual cortex.
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In the visual cortex.
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The information from both eyes gets processed, filtered, interpreted compared with existing patterns and then reassembled into a complete picture.
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Other parts of the brain associate these elements with experiences and emotions.
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Anything missing is filled in.
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All of this usually happens unconsciously, However, important stimuli attract our attention.
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For example, if we recognize a familiar face in the crowd, we look more closely and that irrelevant fluff on the rug.
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We ignore it, so actually we don't see with our eyes we see with our brains and through visual perception, each human being paints a unique mental picture.