The processing of visual signals by our brain is ridiculously complex
Summary
- The brain processes to process visual signals are very complex
Details
- Parallax having 2 different views allows us to see depth of field.
- If one eye is covered, the brain processes other signals to figure out depth such as occlusion, texture adn convergence.
References
Quotes
It doesn’t just rely on the parallax resulting from ocular disparity (that’s the technical way of saying what I just said) though, as this requires two eyes to be working in unison, but when you close or cover one eye, the world doesn’t instantly convert to a flat image. This is because the brain can also use aspects of the image delivered by the retina to work out depth and distance. Things like occlusion (objects covering other objects), texture (fine details in a surface if it’s close but not if it’s far away) and convergence (things up close tend to be much further apart than things in the distance; imagine a long road receding to a single point) and more. While having two eyes is the most beneficial and effective way to work out depth, the brain can get by fine with just one, and can even keep performing tasks that involve fine manipulation.
All this barely scratches the surface. It’s not really possible to convey the true complexity and sophistication of the visual-processing system in a few pages, but I felt it worth the attempt because vision is so complex a neurological process that underpins so much of our lives, and most people think nothing of it until it starts going awry. Consider this section just the tip of the iceberg of the brain’s visual system; there’s a vast amount more in the depths below it. And you can perceive such depths only because the visual system is as complex as it is.