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What Do Blind People Actually See?

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Re: What Do Blind People Actually See?

#81

Post by mkoryak »

A couple of years ago I read a non-fiction book called Crashing Through[1] - about a guy who was blinded by some chemical at a very young age (It went on about some difficulties he had processing the new data. His brain had to "learn" how to see. It was so difficult that he would sometimes close his eyes and and rely on his echolocation skills to navigate.

Very interesting book if you want a first hand account of what it is like to go from being blind to being able to see. (and also about being blind)

[1] http://www.amazon.com/Crashing-Through-Extraordinary-Story-D...

Re: What Do Blind People Actually See?

#82

Post by pje »

Herzog's Land of Silence and Darkness [0], which follows some elderly members of the German deaf-blind community, is one of the most fascinating documentaries I've ever seen. One quote in particular has stuck with me since I saw it years ago:

“People think that deafness means silence, but they are wrong. It is a constant noise that ranges from a gentle whisper going through some cracks to a constant buzz, which is worse.”

[0]: http://en.wikipedia.org/wiki/Land_of_Silence_and_Darkness

Re: What Do Blind People Actually See?

#83

Post by V-2 »

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.

I once read about a blind guy who got his eyesight - thanks to a surgery - after a life-long blindness of about 30 years. He did see, but couldn't process visual information like a normal person (eg. he would only recognize a human face to be a human face after the person began talking)

Re: What Do Blind People Actually See?

#84

Post by agumonkey »

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.

I am fascinated by the notion of color and tone. I suppose you're not deaf so you can feel tone (low and high pitch). I thought that these two 'abstraction' were conceptually the same and hardwired into our brain. But then there might be different roots for blindness and maybe childhood-blind people are having issues at that level (as opposed to eye / optic nerve level).

Re: What Do Blind People Actually See?

#85

Post by agumonkey »

jes5199 wrote: post #56
kazinator wrote: post #45

Earlier quoted context omitted.

I've had a few auras, and my experience was different. There was an ever increasing spot of vision missing, which came to engulf half my vision, but of course I'm aware that the missing part is cutting into my field of vision; I could still map the places in the field of vision where I should see external objects, and imagine something superimposed there. I would say that it was similar to (but eventually larger than…

"scintillating scotoma" is the one with the shimmering edge. I've had that a couple times.

Incredible. I could never find a name for that. I used to have it in early 2Ks. I also had weird brain issues[1], and also have many floaters so I just thought it was one placed just in the worst place, causing refraction. It usually started as a small patch that gradually stretched, moving along the outer edge of my vision. As Wikipedia says, the migraine came a little after that. The last 3 pictures in the article are quite on point : http://en.wikipedia.org/wiki/Scintillating_scotoma

ps : Many thanks

[1] As far as I could search, it's close to sleep epilepsy.

Re: What Do Blind People Actually See?

#86

Post by deanclatworthy »

A great article. I recently visited the "Blind Exhibition" in Warsaw. They show you some items that blind and visually impaired people use on a daily basis and then you have to guess what they are for. I'd never contemplated how blind people know when a coffee cup is full, or pair their socks.

They then take you into a series of rooms (bathroom, the street, art gallery, kitchen etc.) which are completely black. Not a shred of light. You are blind. I can't describe how it felt other than terrifying. I didn't know if my eyes were open or not. It wasn't the black that I saw when closing my eyes, or am sleeping in a dark room. It was this empty hollow of nothingness.

As someone who has always wondered what it's like to be blind then closed my eyes for a few minutes and stumbled around my home - it's nothing like that at all. I left having found a new sense of understanding for the struggles that blind and visually impaired people go through on a daily basis.

An interesting but harrowing statistic they mentioned at the end of our trip was that the majority of people go blind, instead of are born blind. And the main cause is diabetes. It's not uncommon that those with diabetes lose their sight and then their sense of touch. Imagine not being able to feel your way around after going blind.

I highly recommend the exhibition if you're ever in Warsaw, and I think they have it in a couple of other cities: http://niewidzialna.pl/en/

Re: What Do Blind People Actually See?

#87

Post by glaugh »

quantumet wrote: post #34
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…

http://en.wikipedia.org/wiki/Aura_(symptom) It's a grab bag of weird perceptual effects that can precede migrane attacks (and apparently epileptic seizures), and they can be very disconcerting if you don't know about them. In my case (only had them once or twice), I experienced the same visual field disassociation as you did (in addition to the scintillating scotoma thing) - I could see individual things in my field…

I get the blindness aura thing just before I have a migraine (which doesn't happen much anymore since I stopped accidentally suffocating myself with my pillow..).

The experience for me is absolutely identical to that of a blind spot optical illusion, except bigger and in a different area (just a bit off from the center). It's not generally obvious that there's an issue, the brain fills it in, but if I put text in that part of my vision I'll notice I can't actually read it.

Re: What Do Blind People Actually See?

#88

Post by tallanvor »

I'm mostly blind in one eye. --The center of the pupil was destroyed by a parasite when I was very young, and I have no memories of normal sight. I do have some peripheral vision in that eye, but not enough to read or perform normal activities, especially because I have to turn my head to see, such as it is - I can make out certain objects and get a sense of colors, but nothing is clear - reading would be out of the question, for example.

Describing my lack of sight is difficult, because few people have the necessary frame of reference to understand. The best way I've found to describe it is to say that I can only see one side of my nose. Now, I know the other side is there, obviously, because I can look in a mirror and see it with my good eye. But without a mirror, that side of my nose doesn't exist to my vision. --There's not a dark blob or anything like that - it simply does not exist.

It also means I have no real depth perception. I have to try and estimate the distance of an object based on what I know of it's true size - when it's moving towards me, I don't get a real sense that it's actually coming at me, just that it's getting larger at some rate. Needless to say, that makes playing games like baseball very diffciult as there is not necessarily other objects around that make it easier for me to recognize the rate at which the ball is flying towards me.

Re: What Do Blind People Actually See?

#89

Post by gd1 »

DigitalJack wrote: post #23
gd1 wrote: post #11

I suspect you experience true blindness (briefly) during laser eye surgery, when the flap is cut in the cornea. I remember how odd it felt - the feeling of seeing nothing at all, not even darkness.

I could see after the flap was lifted. This was 2005 so I don't know the procedure anymore, but I was supposed to keep my eye trained on a flashing dot while the laser ablated my cornea.

I meant when the blade goes into the eye. There were a few seconds after that before vision came back.

Re: What Do Blind People Actually See?

#90

Post by gd1 »

gd1 wrote: post #11

I suspect you experience true blindness (briefly) during laser eye surgery, when the flap is cut in the cornea. I remember how odd it felt - the feeling of seeing nothing at all, not even darkness.

Here's a reference, you downvoting HN twits:

http://www.realself.com/blog/terrible-lasik-surgery-complica...

"you have to pump the pressure up in the eye to about 6x normal in order to cut a good flap, as you can't cut an accurate flap in a floppy eye. The pressure is actually higher than your blood pressure, so the eye stops perfusing with blood, and you go temporarily blind."

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