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  • visual perception made simple.

  • Yeah, our eyes are like windows to the world.

  • We observe the smallest fluff on the rug and the farthest stars in the sky.

  • At a stadium, we tracked the flight path of a soccer ball and perceived millions of different gradations of car.

  • But how exactly does that work?

  • The essential prerequisite is light.

  • When it enters the eye, it first passes through the lens and the vitreous body before reaching the retina.

  • There, it encounters millions of tiny photo receptor cells with different jobs.

  • Mhm.

  • Three types of cone cells, for instance, react to different wavelengths of light.

  • That's why we can see a variety of colors.

  • However, in order to do their job, the cones need enough light.

  • At night, only the rods are active.

  • They help us to perceive shades of gray and light dark contrasts that keeps us from walking into a lamppost in the dark.

  • But all cats look gray at night.

  • The rods and cones react to the energy of the incoming light and translated into a language.

  • The brain understands electric signals.

  • Other cells down the line process these signals further.

  • Some of those cells heightened light, dark contrasts.

  • Others are in charge of sharpening the image.

  • 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.

  • The bundle tales of the nerve cells form the optic nerve.

  • 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.

  • Because we have two eyes, we also have to optic nerves.

  • These cross paths and travel from the inter brain through a kind of substation straight into the visual cortex.

  • In the visual cortex.

  • The information from both eyes gets processed, filtered, interpreted compared with existing patterns and then reassembled into a complete picture.

  • Other parts of the brain associate these elements with experiences and emotions.

  • Anything missing is filled in.

  • All of this usually happens unconsciously, However, important stimuli attract our attention.

  • For example, if we recognize a familiar face in the crowd, we look more closely and that irrelevant fluff on the rug.

  • 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.

visual perception made simple.

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