IamA Fellow Living With No Depth Perception. AMA!

Would you ever want to try the Oculus Rift to see how you can see with that since many people have been talking about the Rift and that uses the persons sight, so wondering how that would affect you being able to use it?

I wouldn't buy one for myself (I don't have that kinda money lying around), but if somebody let me borrow theirs, I'd try it out. Based on previous experience, for me it'd probably just be like having two separate computer screens strapped to my face with no real 3D effect.

I can, however, imagine specific software that adjusted the viewpoint for each Oculus screen to fool my eyes into thinking they were looking at the same object. That might be handy for vision therapy, if I ever got around to it.

As soon as I read this I thought of that.

Assuming your eyes are at a constant "off" angle they could easily design a program around that.

That's actually something I might look into in the future. Because all my visual pathways are still intact (I'm not blind in one eye, etc.), it may be possible for me to "learn" stereo-vision. An Oculus Rift training program and some eye exercises could help with that.

Wow, if you ever do get around trying something like that, please do record the process. It would be as interesting as watching a blind person see again, or a deaf person getting a hearing implant to hear again.

I most certainly will!

Ever tried a 3DS?

I remember reading somewhere that a guy with a similar problem tried one and cried as it was the first time he'd ever seen depth.

I don't know anybody who owns a 3DS, but the concept intrigues me. I don't honestly think it would work for me, for two reasons. One: my eyes turn out at quite an angle, as you saw in the picture, which would make it hard to get the 3DS screen into the frame of both eyes at the same time, so to speak. And two: the way my brain decided to adapt, I very strongly favor whichever eye I happen to be using at the moment, so I think the 3DS effect would be limited even if my eyes pointed the right way.

But like I've been discussing with the other responders, I'm probably going to do vision therapy exercises, which will eliminate the first problem. Then, maybe I'll get a 3DS and see if I can have the same experience. :)

How do you deal with traffic and such? Probably the most-asked question, but I'm gonna do it anyhow.

I do get that question a lot, but it's a question worth answering.

I deal with traffic the same way I deal with all issues of navigating 3D space with 2D vision: my brain's learned to adapt. I was born like this, so I'm used to it. I can judge depth very approximately by the size of objects and depth cues like parallax and the obvious fact that, if the car is behind the stop sign, it's farther away than the stop sign.

I can drive about as well as anybody else (better than some people around here, I daresay). I did have to get a special note from my eye doctor when I was taking driver's ed, though.

I imagine for someone who, say, lost an eye at 25, driving would be really difficult, but since I've never been able to use both eyes together, I grew up in a flat world and my brain uses different math to get to the same 3D geometry.

Great explanation! I'm blind in one eye (since a stroke at 15) and I think that's how I see. Sort of a mental triangulation. It was hard adjusting to 2-D from 3-D but my brain seems to have done most of the math for me.

I'm sorry you had to experience that. For me, there was never really a feeling of loss, because I was born like this. With you, at least you were pretty young when it happened, so your brain was still nice and malleable. What sometimes makes me sad is wondering what it would be like if somebody lost vision in one eye at 45 or something, when the brain is less plastic.

As someone with no depth perception (monocular vision) I've always struggled with lots of things, like picking up cups, playing some sports, and I've never been able to thread a needle. My optician says I'd be fine to drive, but I don't really see why it would be any easier, especially for things like parallel parking? Is it maybe because it's on a much larger scale?

Ah! I forgot to mention threading needles, which is an enormous pain for me.

To be honest, I was pretty scared when I was learning to drive, and I still despise parallel parking and avoid it like the plague, but to be honest, you adapt to driving like you adapt to anything else. I think when I first started driving, I was excessively cautious. I remember my Driver's Ed teacher telling me not to hit the brakes so early when we came to stoplights. But in ten years of driving, I've only had two accidents, neither of them related to my stereoblindness.

Did you start out with stereovision and then lose it at a young age? That might make the difference.

I was about ten by the time I found out I have refractive amblyopia (a form of lazy eye), so I assume it started to be a problem some time around then. Because my sight is so bad in my left eye, my brain just completely ignores it altogether and relies entirely on my right eye.

Good to hear people with monocular vision have no trouble driving. There may be hope for me yet. :D

Driving should be no problem for you, although be careful, because using one eye exclusively, you might have a slightly restricted field of view. And take my advice: make sure you get a note from your eye doctor when you start driver's ed, or they'll hassle you when they put you on that street-sign machine. XD

I imagine for someone who, say, lost an eye at 25, driving would be really difficult

I lost useful vision in my left eye (some kind of lump arose behind the retina, it distorts the left eye vision into funhouse-like wavers, plus some rotation) when I was 50. I'm nearly 60 now. There are a few small issues, but generally speaking I adapted quickly. I found that my knowledge of the general and relative size of things like cars and so forth pretty much gives me a solid "near-enough" guide so that I can manage just fine. I don't even see the trash my left eye feeds me any more unless I close my right eye and really think about it.

I should have known better than to word that so strongly. :) I've learned a lot about the powers of the brain to adjust to things. And, as somebody else pointed out, actual stereo-vision plays a minimal role beyond a distance of about 10 meters (give or take; I need to look those figures up for myself), which covers almost all of driving.

I've been sort of turning it over in the back of my mind since I saw your post, and I think I've identified the thing that gave me the most trouble; it was pouring wine. I have a heck of a time telling if the wine bottle is over the glass. So I compensate by using the side of my hand to locate the distance of the glass from me, then pull pack, and "tink" touch the bottle neck to the glass before I pour. Completely different approach than what I could do with both eyes, which was aim visually, pour, done.

I can't catch anything that's thrown anymore, either. Doesn't get in my way, I just make sure people don't throw things at me. :)

I'm sure I look very strange when I pour liquids. I don't have (much) trouble aiming the bottle/carton/whatever, but I have to squat down just slightly so I can see how full my glass is, and if my attention is diverted for half a second, I'll usually either track to the side and pour whatever on the counter, or I'll overflow the glass.

Interestingly, one of the extra cues I've developed is to listen to the pitch of the pouring sound, which gives me a more reliable indication of how full the glass is than my eyes do.

Same here.

I drive. I drive pretty well. I ride a bike fast. I do a lot of things that need depth perception. But I don't have it. (Screwed up in one eye). Fuck the system.

Also, there should be a sub for this sort of thing.

I think that's why it's an interesting question. When I mention that I'm stereoblind, the first thing people ask is "Are you able to drive?" It's amazing how well you adapt. Like you, I can drive pretty well, I ride a bike about as well as anybody else, and I very rarely bump into anything.

And there should be a sub for this, if there isn't already. I'll check, and if there's not one, I'll create it. :D

Turns out there is a sub for this sort of thing. It's /r/monocular. I created /r/stereoblind anyway, just because I can.

I also have no depth perception......sounds like the same thing. In some ways, it seems like the way my brain has adapted makes me better at gauging distances than those with the perception. Like driving a car around a parking lot and easily approximating how close the corner of the car is to something when depth see-ers can't.

I can only speak for myself, but I notice that I tend to be more cautious than other drivers, probably because they are able to take driving for granted more than me, whereas I have to be very vigilant to make sure I don't crash into somebody's car.

I also was born with out depth perception due to a lazy eye, it sounds like you have something similar. I forced to wear a patch for ~3 years as a child. Though my lazy eye is more or less undetectable, I still have no stereo vision. However, my brain can still perceive 3D if 2 different images are projected directly to both eyes. Avatar was mind blowing to me in more than one ways man... in like... a WHOLE NEW DIMENSION!

My lazy eye was corrected, but the exotropia wasn't, so I don't think even a 3D movie would do anything for me. I remember when I was a boy I had a science book with those red-cyan 3D anaglyph pictures in it. I looked through one eye and all the red was gone. I looked through the other eye and all the cyan was gone. I didn't get the point, and didn't understand what was going on until much later.

Are you able to choose which eye you're looking out of and switch between on command?

I am! I think that's one of the coolest things about this condition. I just did a quick test, and I can actually switch which eye I'm looking out of a little less than 1.3 times a second, although if I did that too much, it'd probably tire my eyes out.

I feel your pain. I have a different issue- I am long sighted in one eye and short sighted in the other- so my brain only uses one eye at a time.

Do you miss door handles and objects when you reach for them? I still do this often ;-;

It's funny you should mention that, because I'm actually nearsighted in one eye and farsighted in the other, as well.

Proof: my glasses.

And I have trouble reaching for things, too. The paint around my car's doorhandle is all scratched up because I always miss the keyhole, and I have an irritating tendency to knock coffee cups over if I reach for them without paying attention. So I empathize.

Hah, you are my new spirit animal. This is me all over. I wear glasses too.

My parents once tried eye patches when I was kid. Truly awful ;-; and obviously did eff all for me lol.

:D I don't know about you, but it's always a pain when I have to get a new prescription for my glasses, since they have to grind the lenses to two completely different and opposite prescriptions. Makes them more expensive, too, I think.

Yes! And optometrists always get uncomfortably excited about it :/

XD I've been going to the same optometry practice since I was about six months old, so the optometrists there are so jaded they don't even blink when I show up. I'm sure I've got a nice thick file, though.

I should get a regular so they stop flipping out haha. I had a few operations on my eyes as a kid (my eyes turned inwards) so they love my history check lol.

I had 3 operations myself, so if I ever went to a different doctor, I'm sure they'd bring in all the interns to poke and prod me XD

I work in a large optical lab and we only up-charge on power if the power is over a + or - 6.00D. And it can add up depending on the amount of power above that range. We could care less if you are a +5.00 in one eye and a -5.00 in the other (aside from verification of the RX for correctness). The material the lenses are made out of tends to be where the expense comes from on the lab side. But we also don't control how much your office up-charges you on the final product.

My prescription definitely isn't that strong. Thanks for letting me know! Now, if they give me trouble, I can raise a ruckus.

Lol! Well good. Having truly poor vision is such a challenge. Some of the RXs I see on a daily basis provide unique challenges to find something that will even work successfully. Then of course adding in "opticians" that aren't really opticians and have no understanding of how the lenses will turn out and sell customers with super high RXs frames that are totally inappropriate is a daily frustration.

I imagine with all those budget eyeglass places around, and you working in a proper legitimate optical lab, you get frustrated pretty often...

I did work for one of the national chains first. But yet still was competent enough to understand how the final product would turn out to properly advise the patients. But I love the challenge of the lab so much more.

Though, what really scares me are the online retailers. There's really no accountability there. And I've dealt with patients of our accounts that have purchased X-high-end-lens product online and have gotten really really cheap lenses instead (like basically buying a Porche and getting a Kia). Plus, are the RXs verified for accuracy properly? A recent Canadian study said No! I just read it like 2 days ago. Out of 36 single lenses (16 pair of glasses) 6 lenses didn't match the RX and 13 of the 16 frames weren't four-pointed correctly.

I seethe every time some one suggests buying glasses online. My ex did and made up his own RX and the company made it without verifying with a Doctor that is was a legal RX!!!

It doesn't bother me in terms of interfering with my business, but people being duped and thinking they are getting exactly what they want when it's totally not. I got it off the internet so it must be perfect.

I can't buy glasses on the Internet, I wouldn't imagine, but even if my eyes were more normal, I don't think I would. That'd be like buying medication off a dodgy website...

My people!! I am also the same!! I personally have more trouble with navigating doorways LOL

I do tend to brush my shoulders against doorways a lot, but that might be more my general clumsiness than my lack of depth perception.

I thought that, too, but after reading how many of "us" do it, I am now claiming I was never clumsy but I was discriminated against because doorways aren't friendly for people who have no depth perception ;)

I always save that one for the times I do something really clumsy like back into a wall. Then I can say "Hey, you try living with no innate ability to sense three-dimensional position and see how graceful you are." XD

Have you ever walked into a bar?

When I walked in, I walked into the bar. When I left after a few Jack and Cokes, I walked into the bar.

I have exotropia also, so I live in your world. Just wanted to say, it's a bit inaccurate to say we have no "depth perception." We have no binocular vision. We are at a disadvantage compared to those who have binocular vision--but there are monocular depth perception cues, too.

That's a fair point. I was torn between saying "no binocular vision" and "no depth perception," but I didn't want to get too technical in the AMA's title. I'm glad you brought that up, though, because it's an important distinction.

Are you able to play sports? How is your hand-eye-coordination? I'm asking because kids can be ruthless in P.E... Also, thanks for the AMA!

Actually, my lack of depth perception caused me to really dislike sports when I was in school. I have a lot of trouble catching things thrown at me, and like you said, kids in P.E. can be brutal, especially to a clumsy kid who can't catch.

I don't really have the desire to play sports, but I probably could if I wanted to. I can throw pretty accurately, in spite of my problems catching, and I'm a big, sturdy dude. I do still have some hand-eye coordination trouble, so I certainly wouldn't be anybody's most valuable player...

Jeez..hope they didn't poke too much fun at you. Interesting that you're able to aim though. Is it easier if things are close or far away?

Well, I won't pretend they didn't poke fun at me, but I grew a thick skin after a while, and then (around high school), it went from people making fun of my eyes to being curious about them, which is kinda the reason I did this AMA. :)

To be honest, my difficulty catching might be unrelated to my poor depth perception; it might just be that I'm clumsy. But for some reason, I can pretty reliably hit targets. I'm not a great thrower, by any means, but I'm better than you would expect. I can occasionally get a basketball into a hoop, and I'm actually a decent shot with a slingshot or a BB gun or a rifle or a pistol.

Do you have to close one eye when aiming? I do it automatically sometimes (not sure why to be honest). Oh, and do you have a favorite eye?

I think that's one of my advantages when it comes to shooting: I don't have to close one eye; sometimes I still do, though, so my other eye doesn't distract me.

Because one of my eyes is farsighted and the other nearsighted, my favorite eye depends on my activity (and whether or not I'm wearing my glasses). For instance, I almost always use my right eye to look at computer screens, but for driving and long-distance seeing, I almost always use my left.

Ah..which country do you live in? Because for driving I would imagine that it's beneficial to have that left eye being the prominent one because of roundabouts and trying to get out of parking lots and such.

I live in the United States, where we drive on the right, which makes changing lanes a little dodgy. But with my glasses on, both my eyes see in 20/20, so it's not too much of a problem. The real problem is that I've developed a bad habit of leaving my glasses at home. <_<

Do glasses help when looking people in the eyes? My mind is imagining the eye balls just immediatly facing forward as soon as glasses are put on. Please, tell me I'm right..because then it would make all your friends immediatly cross-eyed if they try them on. chuckle

Unfortunately, my eyes are still crossed through the glasses. Fortunately, when I make new friends, I can trick them into trying my glasses on, and the fact that the prescriptions for the two eyes are so radically different makes them go "Woah!", look around like stoners, and then say "Oh god I'm nauseous" and give them back. XD

I had a coworker once who didn't have much depth perception. Tossed a set of keys at him from like ten feet away and he had no idea where to grab for them. I felt kinda bad, that must be a pain in the ass

It's really not too big of a handicap. Somebody mentioned earlier that stereo-vision only works out to a limited distance anyway, and that there are lots of other cues we use to judge the depths of objects.

So it's not a pain in the ass, but there are things about it that are kind of annoying. Not being able to catch worth a crap, for one. And an annoying tendency to mis-reach and knock over coffee cups. But I think one of the most annoying things about it as an adult is knowing that everybody's got this extra dimension to their vision that I don't. I'm not jealous, necessarily (I've never known any other kind of vision than this, so how could I be?), but I am curious what proper stereo-vision would be like.

Meh. You get used to stereo vision and its normal and both thought about much. Either way at least you're pretty used to it. If I walk around with an eye closed, would that put my perception closer to yours? Or is there some other difference?

Walking around with one eye closed is (I imagine) a pretty good approximation of how my vision works. Actually, since I've had almost 26 years to adapt to this, my depth perception would probably be a bit better than yours with one eye closed.

So...Sue Barry, author of Fixing My Gaze, has addressed this question. If someone with binocular vision closes one eye, they actually are not approximating what a stereoblind person sees. The reason for this is that those with binocular vision can close an eye, but still retain the fact that they have experienced binocular vision. So their brain sort of fills in the gaps.

The person with monocular vision does not have that benefit, so it's a poor approximation.

I own that book, but I didn't read far enough to see that. This AMA makes me want to pick it back up.

Having stereovision is no big deal. It comes in handy for fine detail things like catching a ball or sewing, but as you said for the major things it doesn't make a big difference. It makes no difference at all for tv and books because those things are flat anyway. If I close my eyes I don't feel like I see any different but I will still over reach or knock things over. So it's more of a subconscious thing that makes me less clumsy.

I'm pretty much exactly the same way. If we were hunting and gathering on the savannah, you and me would survive just fine :)

Whats the biggest day to day annoyance with this condition?

Thanks for the AMA.

Thanks for the question!

Since my brain's learned to adapt to having no stereo-vision, I don't (usually) have physical trouble getting around. I'd say the biggest day-to-day annoyance is the difficulty I have making eye contact with people. Because of the way my brain adapted, I can choose to either look out my left eye or my right eye, but not both, and because my eyes turn out from each other, if, say I was making eye contact between my left eye and your right eye, my right eye wouldn't be making contact with your left. That unnerves some people. Plus, as a result of having "weird eyes," I got kind of skittish about looking people in the eye at all, which makes social interaction, especially with strangers, a little more awkward.

It's funny you mention that. I am also stereoblind with a similar situation. I tend to look people in the eyes more often from the side, with my head turned slightly. That seems to make people more receptive to it.

My personal strategy is to make eye contact using one eye and to remind myself not to switch which eye I'm using during conversation, because that tends to make people uneasy.

You know, some of that awkwardness is coming from them not knowing what to do either - because they are trying not to make you feel bad. Maybe knowing that it's all coming from a good place will ease the eye-contact scenario for ya

You're absolutely right. When I'm talking to somebody I think is going to end up being more than a casual acquaintance, I always end up explaining the eye thing to them. In my adult life, I've never had a single person be mean about it once I explained it, and once I've explained it, they know why I seem shifty-eyed and they get along with me just fine.

There is a trick you can learn to help with that. If you know which eye you are seeing with you can look slightly to the left or right of the person so that it looks like both your eyes are about even. Also, depending on the angle of your eye turn you can ask an optometrist to prescribe a cosmetic prism lens which will make your eyes appear to be looking more straight.

I usually settle for just making eye contact with one particular eye (usually my left), because, since I'm a little socially awkward anyway, I need a conversation-starter, and my weird eyes make for a good one.

TIL I have a condition worthy of an AMA.

I didn't honestly know whether people would think it worthy or not, but for me, it's always been a sort of ice-breaker, and some people get really curious about it.

Is it scary navigating you're way down stairs?

Not really, although I do have to rely on things like balance and touching handrails more than the average person. Actually, I handle stairs pretty darn well: the only times I've fallen down stairs its' either been because I was in too much of a hurry or I was wearing slippery socks.

does wearing eyepatch help or hinder visual perception?

Excellent question! For me, wearing an eyepatch changes almost nothing. The way my brain has adapted, I can only use one eye at a time, like I said. For example, as I type this, I'm using my right eye. The visual input I get from my left eye is minimal at best: while I'm using my right eye, my left eye goes into corner-of-the-eye vision where I can't discern details, but I can detect movement and color and things like that.

I wouldn't like to wear an eyepatch, though, because one of the ways I've adapted is, if I'm using my right eye and see something that might be threatening or interesting in the low-quality field of my left eye, I switch quickly to my left eye, which I couldn't do with an eyepatch on, meaning I'd still lose a good portion of my visual field.

When I was a kid, I actually had to wear an eyepatch to keep me from becoming so reliant on one eye that I went blind in the other one.

Not to mention ask that extra peripheral vision. It's not all bad.

It's really not that bad at all. At this point in my life, it's nothing but a very occasional annoyance and a curiosity to discuss with people on the Internet. And, like you say, I've got a few extra degrees of peripheral vision, all told.

Hey, me too! I never found out until I was 27 years old. There's no outwardly evident reason why I don't have any depth perception, but I never had an eye test where they checked for it until I was 27..I remember the optometrist telling me "Each one of these circles has another one blah blah something thing floating above it and offset in a certain direction. Just tell me which direction." My response: "Is this some kind of a joke?"

But yeah, that's about how unessential depth perception is. Although it does make a lot of sense because like you, I could never catch for shit (although throwing wasn't a problem) or hit small objects with a stick. I still tend to misjudge distances sometimes and bounce off of doorframes when I try to enter a room and I'm not being careful. Or I could just be really fucking clumsy.

It's really not too hard to get by without stereovision. Even me, with my obviously mis-aligned eyes, I didn't realize my vision worked differently to everybody else's until I was in high school.

Hey there!

I have a similar issue, but never diagnosed or anything like you have done, but my right eye goes off to the right slightly. My left eye is my dominant one and what I normally look at stuff with.

Mine is slight enough that most people don't notice it unless I point it out and sometimes my head decides that it should be normal, and this causes me a huge headache because my head isn't used to seeing things "normal."

Have you ever attempted to watch a 3D movie? How'd that go? Usually ends with a headache for me.

I've never even bothered spending the extra money on a 3D movie. I was just telling another commenter about my experience with those red-blue 3D glasses. I got basically the same experience a person with normal eyes would get if they used the glasses with an eyepatch on. I have no reason to believe a 3D movie would be any different.

My eye dominance is very strong, though, even though it alternates: whichever eye I'm not using has no better than peripheral vision throughout its whole field, so that eye's effectively almost blind.

Same here. Even eye exams where they tell me to focus on something I need to tell them I can't do it with both eyes. lol.

I always just hope something like this will happen: http://www.bbc.com/future/story/20120719-awoken-from-a-2d-world

It's amazing what our brains can deal with, though

I envy that man. I don't think that would work for me, since, as I've said, my eyes turn out so much they get very different views. I think I'd need vision therapy to fix the dodgy eye-muscles before I could have an experience like that.

I suggest vision therapy.

I can loose depth perception at will. I had a lazy eye that I worked on. If i'm uninterested my eye drifts out and I loose 3D. I don't see double, I tend to ignore the vision of an eye. When I am interested in something both my eyes focus and I get proper depth perception. My eyes can look like your proof picture except I can cross my eyes now which is something that I couldn't do when I was young.

If you used a 3D game with an adjusted viewpoint your brain would get used to depth perception and help your muscles to pull into center more. My vision improvement seemed to snowball and get better exponentially. For some of these issues an altered binocular with mirrors can be used compensate for the vision. I highly suggest trying something like this to stimulate the eye by forcing a 3D perspective. It may be a matter of the mind not realizing how depth perception works as well as lazy muscles and the mind may have to be addressed before the muscles.

I've been considering vision therapy for a few years now, but I've been too lazy to look into it, since I'm so used to seeing the world this way. I actually think I'd need to train the muscles and nerves before I trained the neural circuitry. I suspect there's something wrong with one of my cranial nerves, since, after three surgeries, my eyes still turn out. But I have a direct line to one of the best strabismus surgeons in the United States, so maybe he can suggest a place.

You are correct about VT training the muscles first and then the neural circuitry. COVD.org can help you find a place with people trained in vision therapy, they are the association that regulates the optometrists trained in that. I would be interested to hear what your surgeon has to say if you bring it up - most surgeons are not supporters of vision therapy.

And, when I've brought it up, my surgeon did more or less say that I'd never have stereovision, but I never really listened. Besides, I've had three surgeries to correct the outward drift, and the drift has always come back, so the surgeon doesn't have much choice but to admit we need to try another option.

The reason why eye surgery does not fix your problem is because controlling your eyes are way complex and a simple surgery won't teach you how to use your eyes together well. Interesting fact, strabismus (eye turn) is not caused by weak muscles but by the inability to properly control those muscles. It's like doing piano exercises. Though they are called exercises they aren't about making your fingers stronger. They are about learning how to control your fingers to play quickly and accurately. Just as finger surgery won't make you a great piano player, eye surgery won't teach your brain how to control your eyes. I definitely recommend vision therapy. I worked in a vision therapy practice for a while and it really helps a lot. Even if you don't get stereovision at the very least you can learn how to keep your eyes straight while talking to people.

To my limited understanding, you are exactly right. I was really young when I had the first two surgeries, and I think they were done mainly so I wouldn't go blind in either eye. But I never thought to try exercising the nerves and muscles that turn my eyes inward until much later on. Now, like I said, I'm seriously considering looking into vision therapy, especially after talking to all you nice people.

Why haven't you done vision therapy if that could help you gain stereo?

Edit: Just saw your comment below, would stroooongly encourage it to anyone who has this issue, the brain is very plastic and these people* are specialists in retraining it to see in 3-D. Just try it!

*Optometrists trained to do vision therapy - behavioral or developmental optometrists specifically, it's like a specialty within optometry. See COVD.org for more info. They can also help with poor peripheral vision, eye-hand coordination, visual imagery/memory, etc. PM me with questions, I'm not paid to talk about this but I'm good friends with someone who does this professionally and have a couple of friends who did did it for similar reasons.

Thanks for the information! Like I said, I've been considering vision therapy the last few years, and as soon as my family situation stabilizes, I probably will look into it.

Can you see why kids love the taste of Cinnamon Toast Crunch?

I can. It's because cinnamon and sugar are delicious in any number of dimensions.

After reading this I am pretty sure I have a mild form. I used to think I was just clumsy but now I think it is my eyes.

I lay up the table and put the cutlery onto the napkin and then in a split second, ive managed to knock it all onto the floor, eventhough I just placed it down!

Putting things down and picking them up are hard, I often miss. I make a few attempts at grabbing a door handle before I managed to grasp it.

I wear glasses and I do see a little improvement when ive got them on.

I have a lot of trouble with door handles. I don't really notice it, because I'm used to it, but that kind of accurate reaching-and-touching is hard for me. I end up fumbling, sometimes by feel, to find it.

The only thing my glasses help with is improving the vision in my individual eyes (my left is farsighted and my right is very nearsighted). But for people with mild forms, like yourself, I believe you can get special prismatic glasses made which will help adjust the angle of the incoming light so that it hits your eyes in a way that they can form 3D images. But I'm not an optometrist.

Kevin Nealon?

I had to look him up to make sure I wasn't him. I am not him. Who is he? I know he's an actor. Is he stereoblind, too? (Forrest Whittaker has strabismus. I know that much.)

He is an actor who was on SNL back in the late 80's/early 90's. He had a recurring character called "Mr. No Depth Perception", where he would say inappropriate things about people sitting really close to him, believing them to be farther away and out of hearing range.

XD I'll have to look that up.

Protip for anyone wanting to experience /u/hobosullivan 's depth perception limitation for themselves:

(Cool, a lab!)

Close one eye. Go do stuff.

WOW!

^{Was that it?}

XD

Does having exotropia hinder your ability to pluck your eyebrows?

Well, being a man whose personal grooming doesn't extend beyond showering, shaving, and brushing my hair, I wouldn't know, but I imagine I'd be slower at plucking my eyebrows than most people. Shaving (a vaguely similar activity) is interesting for me, because I have to shave one side of my face by looking at the mirror with one eye, and I have to shave the other side using the other eye, so a lot of the time, my shaving is a little asymmetrical, which is embarrassing.

So, straight-razor shaving is out, right?

And your favorite song is *Meatloafs", "Objects in Rear View Mirror, May be Closer than they Appear?

But seriously, my father only had one eye (war injury), and he his lifestyle didn't seem to suffer much for it. He could drive, bowl---I guess the brain adapts. Don't mean to take away from the OP's disability, and I thank him for sharing. I mostly wanted to make a couple of bad deep-perception jokes.

XD Straight-razor shaving is out, but that's more because good luck finding a straight razor these days.

And right you are: the brain adapts. Pretty darn well, actually. Honestly, I wouldn't call myself disabled. I don't feel any more disabled than, say, a guy who's missing a pinkie finger or somebody who's just a little clumsier than average. When you live with it long enough, it becomes more an interesting quirk to tell people about at parties (and on reddit) than a disability. Although catching things is still a pain (and sometimes dangerous).

So, the chainsaw juggling gig didn't work out, eh? Okay, I'll stop. Thanks for being a good sport.

I wouldn't say it didn't work out. It worked out fine for me. It's the audience I felt sorry for...

Do you drink? If so, do you think drunkenness is even more confusing for you than a person with 'normal' vision?

I used to drink sometimes. I've quit at the moment.

Actually, I think extreme drunkenness was less confusing for me than it is for most people, because I'm incapable of getting double vision.

Have you ever had a brief moment of "normal" vision?

For some reason during my reading here my mind wandered to instances of people making themselves go cross eyed. Somehow that lead to wondering whether or not you could force something similar to that for a moment. I'm sure this particular example is ridiculous, but I hope you know what I'm getting at here.

That's actually a really good question. I imagine if I could get my eyes to turn inward enough to point at the same thing, I could have a flash of normal vision. Trouble is, the muscles that do that are very weak and stiff, so I'd probably need to practice for a while before I did it. Also, for some reason, whenever I cross my eyes like that, my eyes go out of focus and I can't make them go back in focus, which spoils the fun.

I can imagine it's hard to do things like drive, etc., but what would people without exotropia be surprised that it affects?

That's a really good question, and I'm having to rack my brain to answer it, because I'm so used to this.

One of the bigger long-term things I have to compensate for is the tendency to become reliant on one eye. I find that I almost always look through my left eye when I drive, but I force myself to use my right eye occasionally so that that visual field doesn't atrophy and get bad at tracking moving objects.

It also makes pouring things into a cup a noticeable hassle. If I look at the cup from the top, I have a lot of trouble accurately judging how full it is by sight alone. I have to listen to the pitch of the flowing liquid. I think the problem there is that pouring is one of those activities that happens close enough to the body that stereovision is very important for doing it right.

I also had a much easier time learning to draw (in spite of my clumsy hands, which aren't related to the exotropia) than most people. The laws of perspective were very intuitive to me, because that's how my brain learned to compensate.

Have you ever been in a fight?

If so, how did it go?

If not, how do you think it would?

Solely from a depth perception standpoint and not your or your opponents actual fighting ability.

I've only been in one fight, and that was in fourth grade, so I don't think it counts. :)

I don't imagine it would go too well for me (because I have trouble aiming things like punches, and, outside of fighting, things like baseball bats and axes). But it would not go well for the other guy, either, because I'm a big sturdy fellow, and probably because of my bad depth perception, I pretty much have no choice but to fight dirty and vicious and take him down as quick as I can by whatever means necessary.

Do you have to pee sitting down?

That's a great question. I don't: I can pee sitting down or standing up. I mentioned before that, for reasons I don't entirely understand, although I'm really bad at catching things accurately, I'm pretty good at aiming things I throw myself. Like, for instance, a stream of urine.

So what do you see exactly? I know this is a vague question. Do you know what 3D is like from looking at a TV? If so how does it compare?

You can do a crude simulation of what I see by putting a bandage or a patch over one of your eyes. At first, it'll probably be disorienting and scary (DON'T try driving like that), but I imagine you'd get used to it pretty quickly.

There's also the fact that whichever eye I'm not using still sends me some visual input. Right now, for instance, I'm using my right eye to look at things. But I still have some vision coming in from my left eye, so it's like the peripheral vision on the left side of my right eye spans forty-five extra degrees.

The only hint I've got for what stereovision would be like comes from things like (wiggle stereoscopy)[http://en.wikipedia.org/wiki/Wiggle_stereoscopy]. For me, in my everyday life, things just don't "pop out." My sense of depth is less intuitive and more abstract, and things certainly don't look 3D.

I was also born with no depth perception! You are not alone! :) (and I am SO glad those 3D pictures aren't as popular as they once were - "but it's RIGHT THERE!" "But I can't see it")

XD I came to hate those magic eye pictures. When they were popular, I was too young to really understand what was going on with my eyes. I would look at them and think "Okay. Here's a jumble of multicolored dots. I'm doing what the instructions say. I don't see any dolphins. What's the deal here? Stop showing me this nonsense!"

Can you draw extremely well as everything is already in 2D?

If my hands weren't so darn clumsy, I could probably draw really well. As it is, I learned to draw perspective a lot faster than most of the other kids, and I paint pretty well since, like you said, everything's already in 2D so I don't have any 3D intuition to fight against.

There's a self-portrait of some famous painter (I couldn't find it) who had very obvious exotropia. I read an article theorizing the same thing: he was a good painter because he didn't have to compensate.

That's awesome, too bad ya got shaky fingers

I could probably have become a painter if I'd ever bothered to practice at it. Maybe someday I will.

Do any optical illusions look different to you? For example: (which way is this lady spinning?)[http://en.wikipedia.org/wiki/Spinning_Dancer]

Well, obviously I can't do that illusion where you cross your eyes and put your fingertips together and see a third hot-dog-shaped finger between them. Or the one where you look through a tube with one eye and see a hole in your hand with the other eye.

At the moment, the lady is spinning clockwise, but for a while, when I looked at her, sometimes I could make her switch directions at will, and sometimes she'd switch directions at random. And I really like things like that spinning PET scan: they are the only things which give me an impression of what it would be like to see in 3D. I could stare at spinning PET scans for hours, probably <_<

Interesting! I was born with a form of this myself: http://en.wikipedia.org/wiki/Amblyopia - but mine was 'curable'.

"In young children with any form of strabismus, the brain may learn to ignore the misaligned eye's image and see only the image from the best-seeing eye. This is called amblyopia, or lazy eye, and results in a loss of binocular vision, impairing depth perception."

See, what they do is they make you wear an eyepatch for a while over your "good" eye, causing you to use only your "bad/weak" eye and making it stronger.

I take it you don't drive in the rain? My father has it worse than me and he doesn't drive in the rain.

I got lucky as far as amblyopia is concerned. One of my aunts had strabismus really bad, and she went completely blind in her non-dominant eye, so my mother was vigilant about that when she saw how my eyes acted. Then, I had the good fortune to work with one of the best eye doctors in the United States, who did aggressive patch therapy when I was very young. My right eye is still a little lazy, but I can use either eye for pretty much any vision task (as long as I remember to wear my glasses, because my right eye is quite nearsighted.)

It is a myth that we need two eyes to see depth.

Wikipedia lists 17 cues that we use for depth perception. Only 3 of them use both eyes. I therefore doubt you have no depth perception at all.

In general, the depth perception cues that use both eyes work only at short distance (Wikipedia mentions 10 meters). For distances larger than that, I expect you to be able to see depth as well as anyone else. I'm therefore also not surprised that you have no problems with driving.

Fair enough.

As somebody else pointed out, I should have titled this AMA "IamA fellow living with no stereovision," but I wasn't sure how widely-known that term was.

Like you say, there are plenty of other cues I can rely on. Perspective and parallax give me all the depth perception I need to survive. But my visual experience of the world within 10 meters is different enough that I thought people might be curious.

When were you diagnosed and how? I was dx'd at 19 with a spatial learning disability but when I take selfies sometimes I notice that I have something similar going on. Dunno if that's just me being paranoid/fixating but I have spatial issues including depth perception problems and awareness of my own body in space.

I was diagnosed when I was an infant. Around six months old, I believe. Exotropia runs in my family, and mine was obvious enough that the eye doctor spotted it right away. And I do have some minor spatial difficulties, but I don't think they're related to my eyes. My father is dyslexic, and I have a lot of trouble remembering which is left and which is right, so I think I inherited some of it from him.

I can't see death either.

You never do. It always sneaks up from behind.

I guess that means you can't use tweezers.

Find someone who can.

I actually have a whole entourage. They're always following me around, constantly threading needles and picking things up with tweezers and looking at Magic Eye pictures for me XD

A little late to the party, so I don't know if you're still answering questions. Can you see a photograph which uses depth as a theme (something with background blur, say) as depth? Being that it's not your eyes perceiving it, but the print of film/digital itself?

I am aware of the depth, but photographs like that don't actually pop out at me the way certain kinds of things like wiggle stereographs do.

Hey! I have double Duane syndrome which has limited my depth perception because it's hard for my eyes to work together but not impossible. I read what you said about occulus rift and I can relate a little bit. If I go to a 3D movie I have a miserable time because it puts an incredible amount of strain on my eyes getting them to render the 3D. The only 3D test I can pass at the optometrist is the fly wings. It's not really relevant to the AMA but it's interesting to see people with similar eye conditions.

I'd never heard of Duane syndrome until you mentioned it and I looked it up.

I've never been to a 3D movie myself because I just assume I wouldn't see any effect. I never saw anything with those red-blue 3D glasses. Besides, I don't wanna pay the extra money to see the darn things. XD

What's the fly wing test? I've never heard of that one.

From my understanding of the fly wing test it's the most basic form of 3D that our eyes are capable of. You put those awkward glasses on and look at a 3D type book thing. There is a picture of a fly and the way the book is made is such that when you put these glasses on the wings are supposed to pop out into 3D space. You are supposed to be able to pinch the wings. There are other 3D tests that normal every day people are supposed to be able to pass pretty easily but I've never been able to.

Edit: Here is the test.

I recognize that booklet, but I don't think my eye doctor ever gave me the fly test. Maybe he didn't think it was worth the trouble. I do believe he gave me some kind of dot-stereoisogram test, which I failed miserably every time.

CATCH!

Does it count if I catch it with my chest and/or face?

I also have exotropia. I've trained my right non-dominant eye to cooperate when necessary, but unless im focusing on it, there is a drift to the right of about 25-30deg off center. Doing this I can get what I think is stereo-vision for about 10 seconds at a time.

One time sticks out in my mind as when i first needed and used stereo-vision. I was in the right hand lane driving next to a large freight truck on my left, another truck was pulling on to the highway at the same speed as the truck on my left. I had to, in about 2 seconds, decide how to handle the situation. Instinctively I locked my eyes in step and was able to determine that at maximum acceleration I would be in front of the merging truck by the time it finished merging.

The only thing that really bothers me about it is that I have the capacity for stereo vision, but my eyes are basically mis-calibrated. That and people who have stereo vision take it for granted. Catching something would be SO much easier if I could see in stereo.

Catching things is one of the most frustrating reminders of my peculiar vision. That, and all these 3D movies that keep coming out.

I can't remember which eye my optometrist told me was my dominant one, but I believe my outward drift is about 10-15 degrees. Like you, I can force my eyes to look at roughly the same point, but for some reason, in order to do this, I have to let them go out of focus, and even then, I just get blurry double vision.

So you're saying you see in 2D, and watch TV in 1D?

I watch TV in 2D, but it's mostly written in 1D.