THE EYE-BRAIN CONNECTIONS! The way the eyes work is nothing at all like a camera; the information is distributed throughout the brain, and the brain then presents a kind of computer-generated simulation based on information and extrapolation. This keeps you from being aware that you are, for example, completely blind during the moment you shift your eyes from one point of attention to another (saccades). Most humans are also blind to extreme changes in the visual field, when the instant of change is concealed.

The coding that occurs at the back of the eye is so complex that it is best to think of the back of the eye as a part of the brain that has been extended forward to the front of the face.

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Ever wish we could visit another planet and see how evolution turned out there? Well, on earth try looking at invertebrates instead of vertebrates.

In octopus eyes the light sensing cells are on the inner surface of the retina, facing the light, unlike vertebrate eyes in which the light sensing cells wound up on the BACK of the retina, facing directly away from the incoming light! The optic nerves also emerge directly from the light-sensing cells.  Thus octopus eyes don't need a fovea, and have no blind spot.

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Color vision in humans: It's important to realize that “color” is not a property of light, and is not an aspect of nature. Instead it is just the way your brain codes varying surface reflectivities in the “computer display” that is your visual field.

Based on shrewd guesses as to how color vision in humans worked, James Clerk Maxwell took the very first color photograph ever made.

Displays that emit light use so-called additive color mixing, as seen in the image, while displays (like a color photo in a magazine) which reflect light use so-called subtractive color mixing.

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