https://en.wikipedia.org/wiki/Retina
Wouldnt it be faster like those cephalopods mentioned in the article above. I couldnt understand half of it.
In: 6
You are mixing two separate things here.
1. The image on the retina is flipped and our brain flips it back. That’s just how lens works: if you focus light on a surface, the image gets flipped, light coming from the left passes through the pupil and gets focused on the right side of the retina and vice versa (including up and down). All non-faceted eyes will work like that, mammal or cephalopod.
2. Our retina is inverted with photosensitive elements on the back side and nerves on the front. Yes, that’s suboptimal. But evolution doesn’t always find an optimal solution first try and a suboptimal one will often get too developed to switch it for anything else. Cephalopods were lucky, we got stuck with suboptimal eyes. There’s a lot of such things in living creatures and they are considered one of the proofs of evolution because intelligent design of species would imply a very bad or drunk engineer.
The way I understand it is that because light travels in a straight line (the light from the bottom a glass travels to the top of your rear eye and the light from the top of the glass travels to the bottom) like a pinhole – this convergence causes the image to be the inverse.
IMO – it’s a sorry ass design – god must have been too tired or was high when he made them. Not unlike a single pipe (esophagus) that’s used for both air and food. Oh and our pleasure center being at the same spot as our waste removal.
What if the optic nerve is inverted and the brain is passed the image right side up? But my guess as to why it is inverted is because it is easier to focus light if the rays travel straight through a focusing lens. Light from the top is coming down through the hole in your eye and wants to keep going down. So the top is on the bottom after passing through the focal point. Provided the optic nerve is inverted, the image is passed to the brain right side up.
As to the question of the brain processing the image “as is” being more “efficient”. The brain is super elastic and dynamic and can over time adjust and deal with changes to nerve signals to process them correctly.
An example of this is that a psychologist wore a pair of glasses that flipped images as they entered his eyeballs. After about a week of wearing those glasses he could perform everything normally and he no longer even consciously noticed the image was upside down.
When he took the glasses off, everything looked upside down for a bit until his brain flipped the image back to normal.
So it’s not like the brain is hardcoded to understand upside down images because of the image flip in the design of the eyeball. Rather the brain takes in the nerve signals from the eyes and processes it along with other nerve signals (such as inner ear) and creates a learned, processed “image” in the brain that’s useful for navigating the world, not a pure unprocessed photo of what the eyeball is actually sensing.
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