Lol I was baiting for someone to say "try staying awake at the wheel but that's a good one bruno!
but seriosly though I thought I was seeing screen flicker and stuff but it turns out that there was no flickering or warping of my screen.
What's actually happening is you are paying so much finite attention to your vision that you are starting to notice the effects of your pulse on the shape of your cornea, eye twitches, quivering and stuff. Normally your brain filters that stuff out of the mental image and you don’t "see" it until you start looking for it.
The changes in sky color, lightness, hue etc. is from the lagtime between what your eye sees and the mental image projected. This is the lagtime magicians exploit with "slight of hand"
the lag time increases and vision acuity and accuracy decreases the more tired you get.
your brain doesn't take constant movie of everything that your eyes send it...
it takes snapshots something like every 1/3 of a second, notices what's different, processes what's different, and fills in the rest from memory when it prints the image out in your vision center for your mind to see.
that's why when you try to notice any details about say the leaves on a tree at the edge of yoru vision... you normally can;t describe any.
it's because you brain is filling in the space with a representation of what it thinks should be there.
Unless you specially train yourself to notice everything (very tiring) what you are seeing outside of the center of your vision is a combination of what;s there filled in with images from memory.
A person visible but to the extreme of your peripheral vision of might not even appear to have a face or they might all have similar faces or you might not be able to identify who they are unless you direct your attention to that person.
it's not because your eyes cannot see perfectly there. they can.
it's because the brain is conserving resources and thinks it does not need to see perfectly except in th ecenter of where you are looking.
I noticed that driving at night is less fatiguing to me and I assume it is probably because there is just less to see.
if you train yourself to ignore the things which are irrelevant to your path down the road you can drive a lot farther without getting tired.
You simply do not always need to see every doughnut in every window