From what I've gathered (lifelong glasses user) your brain can adjust for your crappy vision. It refines and fixes based on what it thinks should be there and is usually pretty good at it. When you get glasses and it no longer has to do that work (because the eye is transmitting a clearer image) it gets lazy and stops working on that refine and fix for the blurred vision. If you kept your glasses off long enough it may stay the same or you may adjust to it and think the blurs are normal because your brain is "erasing" them in real time based on what it knows something should look like.
The refine/ fix thing is a perfectly normal thing for the brain to do and it does it constantly in ways we mostly don't pay attention to (peripheral vision is a huge one for this) because it gets it right 99% of the time. The times it doesn't tend to produce things like shadow people or things that make you double-take and focus on an object because the fix the brain did was off enough for you to recognize it but focusing gave it more data to do it right.
tl;dr your brain is fuckin' weird and makes shit up constantly and when it doesn't have to do that it's a lazy fuck that sits on the couch and demands sugar, fat, and caffeine.
Vanyeetus t1_j1yonmc wrote
Reply to comment by Isaiah_6_8 in ELI5: When scientists say babies have blurred vision, how do they know? by DreadMCYT
From what I've gathered (lifelong glasses user) your brain can adjust for your crappy vision. It refines and fixes based on what it thinks should be there and is usually pretty good at it. When you get glasses and it no longer has to do that work (because the eye is transmitting a clearer image) it gets lazy and stops working on that refine and fix for the blurred vision. If you kept your glasses off long enough it may stay the same or you may adjust to it and think the blurs are normal because your brain is "erasing" them in real time based on what it knows something should look like.
The refine/ fix thing is a perfectly normal thing for the brain to do and it does it constantly in ways we mostly don't pay attention to (peripheral vision is a huge one for this) because it gets it right 99% of the time. The times it doesn't tend to produce things like shadow people or things that make you double-take and focus on an object because the fix the brain did was off enough for you to recognize it but focusing gave it more data to do it right.
tl;dr your brain is fuckin' weird and makes shit up constantly and when it doesn't have to do that it's a lazy fuck that sits on the couch and demands sugar, fat, and caffeine.