The Brain and Space

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My newest class is The Brain and Space.  (Yes, I'm enrolled in three classes now.  Science of Happiness, Geospatial Intelligence, and The Brain and Space.  One thing that makes this comfortably do-able is that SoH and BaS are both "do at your own pace" over many months.  There are deadlines, but they are months away.  Only GEOINT is mired in anachronistic bricks&mortar-style constricting weekly deadlines.  Ask me how I feel about these gratuitous tight deadlines..........)

This week in The Brain and Space we are learning how the eye works.  How our eyes enable us to collect light.  One of the things that baffled early scientists (including Leonardo da Vinci) who looked at vision is that the lens puts an upside-down image on the retina.

How does the image get right-side-up again, so we can see up and down properly?  Our brains flip the image for us, so what we perceive is a right-side-up world..........  Pretty complex and amazing.

This is a drawing by Decartes -- it doesn't show that the image is upside-down (and backwards!) when it hits the retina, but I think it is cool..........

It does show that there is light reflected from any particular point in multiple directions, many of which make it through our pupils into our eyes, and shows that our lenses focus the light so that light from one particular point ends up on one particular point of our retinas (assuming our eyes are able to focus properly).

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