Sara20’s brain has realized what the world looks like with glasses and is no longer willing to accept it without.
When I first got contact lenses I had weird experiences because suddenly I could see my feet or the front tire of my bicycle – things that were until then completely ignored because they were outside the field of view of my glasses.
A year ago I got progressive lenses in my glasses and it took several weeks to adapt to them because I could no longer see where I was going while walking downstairs unless I tilted my head down. The brain adapts.
I got glasses later in life and experienced this exact same phenomenon. I felt like my eyes were far worse than they had been before I got glasses. I mentioned it to my optometrist and he explained that it’s not your eyes that get worse, but your brain just stops working so hard to interpret the blur. Your eyes see the same blur as before, but now your brain has relaxed, because it has gotten used to seeing clearly.
I found that if I wake up and do not put my glasses on, my brain does a better job of adapting to the blur and my vision seems to go most of the way back to how it was before I ever had glasses. But if you wear glasses and then take them off, you “see” the fully blurred image because your brain has relaxed.