It's amazing that you guys seem to be having these experiences. I've been seeing 'pixels' in real life ever since i was a kid. I still do. I assumed that everyone sees this type of 'phenomenon', so i never bothered.
yeah me too. always had 'em, and never thought anything of it.
when I close my eyes they're even better, wierd shifting checkerboard patterns, or swirls, or geometric shapes, or whatever.
'glowing halos' happen when you hold your vision on the same object for a while and get retina 'burn-in'. its not really 'burnt in' but the receivers locally adjust to the light level, I think.
sparkly bits floating around? yeah them too. all kinds of reasons, starting with: random noise in nerve signal, also bits on the eye-lense. sometimes this even looks stereoscopic.
fixating on an image then causing 'flexing' in and out - yeah, seen that. I think that is to do with a breakdown 'or change in 'mode', in the way your brain filters/processes an image, so that after a while it 'stops' filtering it to look static, and you see natural undulations due to movement of the eyeball, or the optic nerve, due to blood circulation or involuntary muscular movements, or somesuch? (erm.. I couldn't explain that very well, and I'm speculating quite blatantly here too, sorry!)
also, the margins, and 'interference patterns' you get at the very edge of objects seen close up - I put that down to the wave interference effect we did in physics. (um, and never really thought it through in detail!)
plus your brain has a tendency to interpret random noise according to what's on your mind: After a week of skiing, when I shut my eyes, all I could see was miles of snow-drifts, and it really
looks like that!
there are loads of good optical illusions on the web, which highlight how the brain does these various tricks, and how there is a lot
of 'processing' between the eyeball receptors, and what your brain 'sees'. The brain actually 'invents' a lot of what you see based on all kinds of things. One classic example is how it invents the bit of signal for the hole where the optic nerve leaves the back of the eyeball, and you can do a trick whereby you stare at a dot on a piece of paper, and it disappears (can't remember the setup, unfortunately, if its one dot or two? and where to stare?) because it is in the 'dead zone' so your eye extrapolates the bits of vision on either side.
I think most of the various phenomena are physiologically explainable, though I'm no expert on the subject, so don't take my word for it
I had a go at trying to 'see auras' after reading 'The Celestine Prophesy' a while back, but all I saw were the various types of 'noise' described above, really. so I think of it all as just a vaguely pointless distraction, so I don't make anything of it. 4d bleedthrough? who knows, but I doubt it.