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What Do Blind People Actually See?

nautil.us

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Re: What Do Blind People Actually See?

#71

Post by aliakbarkhan »

hentrep wrote: post #27
Chinjut wrote: post #10

Earlier quoted context omitted.

Why should the concept of color be harder to wrap one's mind around or describe than the concept of sight itself? Or, considering any animal with any kind of sensory receptors other than those you yourself have, wrapping your mind around or describing the concept of the data produced by such receptors? [A bat's echolocatory sense, say, or magnetoception...] ["Oh, it's easy to understand the PHYSICS and BIOLOGY of col…

I suppose what I was getting at is this: How do you explain what color is to a natively-blind person in a non-mathematical, non-physics based approach? In other words, the way most of the world learns about color (qualitatively). You can't use words like "shade" or "hue", because the very definition of those words are themselves tied to color. For example, attempt to describe a baseball. Descriptions invoking roundne…

Try looking into qualia. http://en.wikipedia.org/wiki/Qualia

Re: What Do Blind People Actually See?

#72

Post by gohrt »

Rapzid wrote: post #62
jareds wrote: post #57

Earlier quoted context omitted.

Nothing, it looks the same to me.

I suppose it is possible you're perceiving the light as a particular color, but if you can only perceive that color you would mistaken it for white?

I don't know what jareds's situation is, but normal humans have light sensors that are not color sensors, and also have color sensors

http://en.wikipedia.org/wiki/Photoreceptor_cell

Re: What Do Blind People Actually See?

#73

Post by icantthinkofone »

Many years ago, blind people might put their hands on your face to help them get a sense of you. A blind friend of mine, Jim, got in the car with us, one night, and sat next to a friend he did not know. He put his hands on the other guy's face, then paused, then said, "Man, you are uuuuuugly!".

Re: What Do Blind People Actually See?

#74

Post by gohrt »

eranation wrote: post #51
bramd wrote: post #35

First of all, be aware that the group that's actually totally blind is relatively small. Most people who are legally blind have some form of light perception, or can see something. I've been totally blind since birth. Blind people can have a good or bad sense of direction, just like their sighted peers. I think the device described in the article might be more useful on short distances and less relevant for knowing w…

> I've been totally blind since birth. Please forgive me for the naive question, I'm probably full of misconceptions about blindness, but out of pure curiosity, how do you read and write so well without seeing? Is the technology so advanced today? Are you using a screen reader and a regular keyboard? (e.g. typing and than playing it via the reader) how do you know if you made a typo? (e.g. who's and whose sound the s…

TV Raman has done a lot of work and storytelling relating to his blindness. He is a CS researcher at Google:

http://en.wikipedia.org/wiki/T._V._Raman

Re: What Do Blind People Actually See?

#75

Post by gohrt »

janus wrote: post #48

This story reminded me of the guy that had a magnet implanted in his pinky finger, who was then able to sense electromagnetic fields and other stuff http://gizmodo.com/5895555/i-have-a-magnet-implant-in-my-fin...

Implant seems extreme. One could do well with, say, compass armbad with a strong magnet and a pokey attacmhent.

Re: What Do Blind People Actually See?

#76

Post by jtheory »

skygazer wrote: post #68
sillysaurus3 wrote: post #28

Earlier quoted context omitted.

It's extremely odd- one's visual field (at least in our cases) steadily contracts, until there's just nothing left. It's not an annulus of darkness closing in, it's juts nothing- the field you can see is smaller, and there's still nothing outside of it, just like there always isn't. This is the first time I've heard of anyone else experiencing this phenomenon besides myself. Have there ever been any long-term effects…

I suffered something similar, just once, about twenty years ago, in high school, and never since. Although, instead of an impression of nothingness, it felt more like a Photoshop content aware fill, similar to the optic nerve blind spot, but moved to the fovea. I was walking the hall to my first period, mainly looking at the bland floor tiles, and didn't realize anything was abnormal. When I happened to look up at th…

The content-aware fill is what I get as well -- I have some permanent blind areas in my right eye due to optic nerve damage; I lost a lot of peripheral vision, but also the normal optic nerve blind spot is quite a bit larger in that eye -- about 1/4 of the height of my visual field, and half as wide -- fortunately still not affecting the central point of focus.

Obviously no black patch or anything like that; I first noticed the missing section (before I had visual field tests done to detect it properly) while driving, stopped at a light; I rubbed my other eye momentarily, and the traffic light vanished.

Re: What Do Blind People Actually See?

#77

Post by jimmaswell »

hentrep wrote: post #27
Chinjut wrote: post #10

Earlier quoted context omitted.

Why should the concept of color be harder to wrap one's mind around or describe than the concept of sight itself? Or, considering any animal with any kind of sensory receptors other than those you yourself have, wrapping your mind around or describing the concept of the data produced by such receptors? [A bat's echolocatory sense, say, or magnetoception...] ["Oh, it's easy to understand the PHYSICS and BIOLOGY of col…

I suppose what I was getting at is this: How do you explain what color is to a natively-blind person in a non-mathematical, non-physics based approach? In other words, the way most of the world learns about color (qualitatively). You can't use words like "shade" or "hue", because the very definition of those words are themselves tied to color. For example, attempt to describe a baseball. Descriptions invoking roundne…

This was touched on in The Giver, interestingly. The main character becomes able to see color after never having been able to.

Re: What Do Blind People Actually See?

#78

Post by heinrich5991 »

tempestn wrote: post #46
StavrosK wrote: post #30

Earlier quoted context omitted.

I've heard it described that blind people see what we see out of our left eye when we only have our right eye open. It's not blackness, it's just no perception.

That is a very interesting observation! When we close both eyes, we perceive a blackness, or perhaps some sort of reddish/purplish glow of light through eyelids, or the after-effect of light. However, by keeping one eye open, it seems any signal from the closed eye is overridden, so you really don't perceive anything there.

I can differentiate between light or no light in front of my closed eye, even if the other eye is open. Is this the inverse effect of the effect you're talking about?

Re: What Do Blind People Actually See?

#79

Post by jtheory »

einhverfr wrote: post #52
jareds wrote: post #2

As someone who has been blind since birth this is accurate. I know that people who go blind later in life continue to dream in color since they have the memory of color to reference while I do not. I wonder if someone who goes blind later in life experiences things differently, possibly by automatically filling in what they assume they would see based on what they know of there surroundings from there other sences.

Also since blindness is a lack of sight as we know it, it is a very large category of phenomenon. Someone who goes temporarily blind from a blow to the head may experience something differently from someone with retinal damage. Someone who has never been able to see may experience things differently from someone who has recently suffered blindness as a result of injury or illness (and these themselves might have diff…

Right! I felt like no one was quite pointing this out.

Your brain is expecting certain input in given situations, and you have layers and layers of habits based on those expectations.

If you are accustomed to NOT having that input, you don't expect it. You don't fake it (imagining a black space of the size a visual field would be...), you just don't have it, and it's not a part of your interactions with the world.

If the shape of your visual field changes suddenly -- you're about to pass out and you get "tunnel vision" -- it's obvious and startling. If it changes gradually, you don't even notice; you just start hitting your head on low beams more often, or bumping into table edges as you go by, until you adjust (this is from experience...).

Re: What Do Blind People Actually See?

#80

Post by tylerpachal »

For me this raises a question on a slightly different topic: if you're born deaf, what languages do you think in? I can consciously think in English and French, but if you have never heard a spoken language before, what would your thoughts be like?
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