3 ms·

The survival bias, but still: I had a normal vision since I was born until I got an artificial lens in my right eye at 9 y.o. to deal with glaucoma caused by t

The survival bias, but still: I had a normal vision since I was born until I got an artificial lens in my right eye at 9 y.o. to deal with glaucoma caused by trauma. As you may guess, this new lens is not even close to the biological, as it has different elasticity and light refraction properties. The picture from my right eye is heavily abberrated, but my brain applies inverted abberation to the left eye's picture to have an almost perfect binocular vision. It wasn't like that on day 1 from operation, but progressed over a couple of years. Same thing with lens focus - it was 20/200 when I leaved the hospital, 20/30 after a year and 20/20 in two more, although the abberations couldn't be fixed.

el_benhameen 7y ago
Similar experience, though kind of in reverse. I was born with a congenital cataract in my left eye, and my brain learned to either correct or tune out the picture from that eye. When I closed my right eye, the left picture was significantly darker and had a large black spot near the center, but with both eyes open I had very good (I guess? Hard to compare when you've known nothing else) vision. I got the bright idea to have cataract surgery in my late 20's despite the cataract never really bothering me. While the sight in my left eye is now objectively "better", the surgery actually made my binocular vision worse because my brain isn't used to the new type and degree of aberration, and so doesn't yet know how to correct for it. I'm a few years out from the surgery and it's definitely better, but I kind of wish I'd left well enough alone.
rcthompson 7y ago
Consider that your brain already has to do this anyway even with all-natural eyes. It receives an independent image from each separate eye, so it has to line the two images up with each other in order to produce binocular vision. It's not as if your eyes come pre-calibrated or something, and even if they did, your skull grows throughout your life, so the alignment of eyes relative to each other must change over time, requiring your brain to gradually recalibrate. So it makes sense that the brain would be able to recalibrate to an artificial change in your vision as well.

el_benhameen 7y ago

Similar experience, though kind of in reverse. I was born with a congenital cataract in my left eye, and my brain learned to either correct or tune out the picture from that eye. When I closed my right eye, the left picture was significantly darker and had a large black spot near the center, but with both eyes open I had very good (I guess? Hard to compare when you've known nothing else) vision. I got the bright idea to have cataract surgery in my late 20's despite the cataract never really bothering me. While the sight in my left eye is now objectively "better", the surgery actually made my binocular vision worse because my brain isn't used to the new type and degree of aberration, and so doesn't yet know how to correct for it. I'm a few years out from the surgery and it's definitely better, but I kind of wish I'd left well enough alone.

rcthompson 7y ago

Consider that your brain already has to do this anyway even with all-natural eyes. It receives an independent image from each separate eye, so it has to line the two images up with each other in order to produce binocular vision. It's not as if your eyes come pre-calibrated or something, and even if they did, your skull grows throughout your life, so the alignment of eyes relative to each other must change over time, requiring your brain to gradually recalibrate. So it makes sense that the brain would be able to recalibrate to an artificial change in your vision as well.