I am sitting here writing this post with an eyepatch over my right eye. I had surgery 2 and a half years ago to make my eyes look straight (they were slightly crossed), and had wonderful single-vision afterward. Recently, however, my left eye has been getting weaker and has started to turn in again.
Now, this is causing me a lot of eye strain and general annoyance, especially with my upcoming departure to foreign lands. I visited my optometrist, who agreed that my left eye has gotten pretty crossed and is, in fact, awfully close to as crossed as it was before I had the surgery. This was disappointing, to say the least. So I made an appointment with my surgeon the next day to see what he thought I could do about it for the next two years, since there is certainly no way that I could have surgery before I leave.
The surgeon thinks that it is a muscle weakness problem, which is apparently not that rare of an occurrence a few years after surgery. We decided that my best bet would be to patch my right eye for a few hours every day to force my left eye to get stronger.
There are several interesting results of one-eyed vision that you lucky people with two, functional, straight-looking eyeballs would never even think of. The first is that, although my body is good at knowing where its parts are in space, it turns out that the brain relies quite heavily on being able to simultaneously see that body part. It can certainly get by without it, and it does this by automatically relying more on tough. Where previously I would reach for a coffee cup handle, even just using my peripheral vision to guide my hand to the right place, my body now guesses where it is, and then carefully bumps my hand into it and adjusts according to what was felt.
This is true even for things that are in the visual field of my left eye (the seeing one), because I am lacking depth perception. My hands are much less sure of where to go to hit light switches, pick things up, etc, but it ends up not being a problem because my brain shifts dominance from sight to touch. Automatically. Not at first though; it seemed to take about half an hour of being patched.
The wierdest thing is that, if I am not paying attention at all to the fact that my right eye is patches, I actually start to see things in my periphery that are not in my visual field. For example, there is a coffee cup to my right, and all I can see with my left eye is the very edge of it. However, while I look straight ahead and type, I can actually “see” most of the cup. It’s pretty fuzzy, but apparently my brain knows what it looks like and just fills it in as if my right eye was seeing to some degree.
Anyway, this is just a long, rambling way of saying that having two eyes is great, even if one of them doesn’t work properly. For anyone reading this with two eyeballs, GIVE YOUR EYES A HUG.