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Whats up with my vision?
January 30, 2012 12:36 AM   Subscribe

Whats up with my vision? I sporadically have a condition I have trouble describing.

Sometimes, when looking at something with lots of complicated 3d details, for example a large crowd strolling through dappled sunlight, or closely watching water come to a boil in a glass pot, my vision shifts oddly. Yesterday it happened while looking at a huge mass of fine ice crystals I found on freezer-burned food.

Its hard to describe objectively... I can look around normally, see all the usual colors and details, everything still in focus, same brightness, nothing concrete missing. But somehow it what I see seems less cohesive, no solidity, just a bunch of details that no longer form a whole. Then a minute or two later, its all back to normal.

Is this some obscure medical condition? I have difficulty even coming up with a proper description or search keywords. It doesn't cause me any problems other than being distracting. Its occurred sporadically since childhood - maybe once per month at most. My right eye is strongly dominant, if thats important.
posted by Hither to Health & Fitness (12 answers total)
I get it so I vote for it being completely and utterly normal. Or a terrible sign of impending madness.

I have an astigmatism in one eye and had always put it down to astigmatic shenanigans. I'm also curious about it.

I also can't do those 3d stereograohicy pictures .
It's like an enormous joke that everyone else is in on, to me. Can you "do" those?
posted by taff at 1:03 AM on January 30, 2012

Um, guessing at words to google...changes in closeup depth perception...?
posted by taff at 1:05 AM on January 30, 2012

If I'm understanding right, I get the same thing when I look fairly closely at a pattern that replicates (or nearly replicates) horizontally relative to my orientation. It's the opposite of the Magic Eye stereoscopic pictures. Your eyes cross, "lock on" to the overlapping similar parts of the pattern, and you see some parts clearly, closer than they actually are, and other parts that don't match up are indistinct and confusing.

Now, if this is happening for more than a few seconds at a time, with moving, changing objects, it might not be this. Or it could be and it's just a weird brain fluke.

To test, find a regular pattern - maybe your keyboard will do. Place your face about 5 inches away from it, with a repeating part of the pattern aligning with your eyes. Cross your eyes slowly, so you see double, and align one double image of the pattern (or keyboard key) with a different part of the other eye's image. The pattern will "pop out" at you. Does that look similar?
posted by WasabiFlux at 1:13 AM on January 30, 2012

Or when looking through a window screen you suddenly focus on the screen and not what's outside? And once focused on the screen, it's hard to refocus beyond it? How old are you?
posted by three blind mice at 2:26 AM on January 30, 2012

I'll pop in with a neuroscience fact or two. I'm certainly not any kind of doctor, though - just a student.

There are neurological conditions of vision in which people cannot see a whole scene; they can LITERALLY only see one object at a time, at the expense of even recognizing the presence of anything else. This is called simultagnosia (agnosia is the general word for a specific neurological deficit). Less severely it is possible to have a kind of agnosia where one only perceives details, not a whole, but is still able to recognize that other visual information is present.

I believe that simultagnosia often comes with anosagnosia (not knowing that you have a deficit). Clearly you don't have that, and it sure doesn't sound to me like you have any of the official conditions I've heard of (though, again, I'm no kind of doctor). But the brain is unimaginably complex, and almost all brain "disorders" fall on a spectrum - none of us are 100% "normal". If I had to take a guess, I'd say you have a harmless window in to the incredible processing your brain does all the time - cool!

(Personally, I *think* I have experienced something similar. It always happens in the shower when I'm looking at tiles on the wall, very close up. Suddenly my sense of depth disappears and it seems that I'm looking in to a strangely 3D abstract scene. The "wall-ness" just disappears.)

By the way, these are fascinating conditions which give us insight in to how vision works. The fact that people are capable of seeing "only one object" indicates that our brains parse the visual world in to "objects" - which is no simple task! (Plus, what constitutes an object is being constantly redefined! If the view is of a large room, a chair might be an object-unit. If one is directed to look closely at a chair, the arm of the chair might become an object-unit, and so on.)

Here is a YouTube video I just found of a man describing his simultagnosia and autism. Unfortunately I can't link you to the videos I was shown in my neuroscience classes of people with this condition because they are behind a paywall.
posted by Cygnet at 5:01 AM on January 30, 2012 [1 favorite]

It could be a migraine headache. These can produce vision problems. Your head may not hurt but it still is the same mechanism
posted by thermonuclear.jive.turkey at 5:15 AM on January 30, 2012 [1 favorite]

If I go to a website with a dark background and light colored text my vision goes all wonky - triggers a visual migraine if I stare at it too long. This got notably worse in my late 40s. When did you get your vision tested last?
posted by leslies at 5:43 AM on January 30, 2012

Hit post too soon - meant to add that I also have significant astigmatism.
posted by leslies at 5:44 AM on January 30, 2012

I get optical migraines that are caused by movement of light. Dappled light, moving water, light moving on crowds or ice all the things you mentioned can set them off randomly. Once I get one my vision goes crazy for a while, no headaches or similar just my vision gets "weird", the weirdness can vary from attack to attack and usually takes an hour or so to get back to normal.

I would mention it to a doctor next time you are there, as mine is indirectly caused by a mild but annoying neurological problem, having said that when ever the subject has come up conversation it appears a lot of people get them without having anything else wrong.

I'd get my eyes checked though it could just be you need glasses.
posted by wwax at 7:00 AM on January 30, 2012 [1 favorite]

taff: Indeed, I've never had any luck with stereograms.

WasabiFlux: I had thought it might have something to do with motion, because often it has come from seeing lots of complex motion, but the latest instance where it was just some ice in front of me makes me think otherwise.

three blind mice, leslies: I don't think I've ever had those happen. I'm 29. I think these episodes might actually be decreasing in frequency as I get older, though I haven't really been keeping records or anything.

Cygnet: I have idly wondered what it says about my brain's processing. My hand-wavey hypothesis was that processing the object-identification information became too 'computationally complex', so that processing functioning is turned off or broken until its had a chance to 'reset'.
posted by Hither at 7:46 AM on January 30, 2012

This sounds familiar to me. I have some challenges in perception and stereoscopy because of a lazy eye in childhood. Something that works for me in "rebooting" from this is to close one eye for several seconds.
posted by Sidhedevil at 10:54 AM on January 30, 2012

I have a similar thing happen sometimes, notably when I'm reading the newspaper in the morning. It just lasts a few seconds, until I make it stop (I'm not sure how I do this). I also have a strongly dominant right eye, a lazy left eye, and have never been able to see a "Magic Eye" picture. It happens more with my glasses than with my contacts, I believe.

So... no idea about what it is or what it's called, but hi there.
posted by The corpse in the library at 10:30 AM on January 31, 2012

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