What do Blind People See?

[ddviper]

ive always wondered what blind people see, especially ones that may have had cancer and now dont have any phyiscal eyes at all (poor people ) do they see black? or do they see nothing?

(by nothing i mean close your eyes and turn your head. Sitck your finger out and point it at the monitor. Trying seeing with your finger, thats what i mean by nothiningness.)

 

[imported_Snagle]

whoaw....

 

[CycloWizard]

Depends on which blind person you ask. I don't actually know anyone that has been blind their entire life. I do know people that have suffered from severe macular degeneration that leads to blindness. In the case I'm most familiar with, my grandmother, she still 'saw' things, though mostly they were hallucinations. I'm not sure if the hallucinations were independent of the onset of blindness or if they were inherently linked.

As for the general case, I would suppose it would depend on the cause of blindness. I've heard of cases where the optic nerve is damaged or severed. I would assume that in such cases, the people see nothing unless their brain can somehow decode the noise electricity in the optic nerve. I'll be able to tell you a lot more in a few weeks, as I'm just starting research in this area (as of last week ).

 

[ahurtt]

Originally posted by: CycloWizard
In the case I'm most familiar with, my grandmother, she still 'saw' things, though mostly they were hallucinations. I'm not sure if the hallucinations were independent of the onset of blindness or if they were inherently linked.

I wonder if her hallucinations were analogous to the "phantom pains" that people feel who loose limbs?

 

[Nebben]

I've always wondered the same thing... let me know if you find anything out. My best guess is that they don't "see" anything...

When I close my eyes, I see black, because I know what it's like to see, and the blackness I see is the inside of my eyelids lacking any light. So if somebody's been blind since birth, and their eyes have zero ability to sense light, I'm not sure what they'd "see" because there's no sensation in existence.

I'm going to guess that there's no way for a person with normal vision to understand what a person who is completely blind since birth "sees" because that person has no understanding of what vision is.

 

[hondAS2ooo170]

they c white

 

[ddviper]

Originally posted by: Nebben
I've always wondered the same thing... let me know if you find anything out. My best guess is that they don't "see" anything...

When I close my eyes, I see black, because I know what it's like to see, and the blackness I see is the inside of my eyelids lacking any light. So if somebody's been blind since birth, and their eyes have zero ability to sense light, I'm not sure what they'd "see" because there's no sensation in existence.

I'm going to guess that there's no way for a person with normal vision to understand what a person who is completely blind since birth "sees" because that person has no understanding of what vision is.

thats wat i was thinking too, but was just cing if nebody else had any explination that could explain it a little better to me

 

[Matthias99]

Originally posted by: ddviper

Originally posted by: Nebben
I've always wondered the same thing... let me know if you find anything out. My best guess is that they don't "see" anything...

When I close my eyes, I see black, because I know what it's like to see, and the blackness I see is the inside of my eyelids lacking any light. So if somebody's been blind since birth, and their eyes have zero ability to sense light, I'm not sure what they'd "see" because there's no sensation in existence.

I'm going to guess that there's no way for a person with normal vision to understand what a person who is completely blind since birth "sees" because that person has no understanding of what vision is.

thats wat i was thinking too, but was just cing if nebody else had any explination that could explain it a little better to me

Odds are they really incapable of "seeing" anything, and probably wouldn't see much even if you somehow fixed their eyes. The visual processing areas of their brain would be dramatically underdeveloped and less connected to the rest of their brain than in someone who could see from birth. The extra neurons would have probably been assimilated into their other senses (hearing, touch, etc.) Someone who could see but was then blinded might see "blackness", since that's what their brain "knows" to tell them when it's not getting any input from the rods and cones in the eyes. Interestingly, people like this still have visually-based dreams; the wiring's there in the brain, but there's no input going to it.

Asking what someone who has been blind since birth "sees" is a philosophical question (like one of those Zen riddles, eg. tree falling in forest, etc.). There's no good way to answer it in a definitive fashion.

 

[spaceghost21]

I don't know anyone blind, but I've always thought about it this way: Someone blind trying to see would be like you or me trying to use some sixth sense, you just plain can't.

 

[mrCide]

going along the same lines, a person who's born deaf, what do they hear in their head? you teach them sign language, do they think in sign?

weird thought.

 

[sao123]

The most common myth is that blind people live in a world of total
darkness.

In fact only about 18 per cent of blind people are classed as
totally blind and the majority of these can still distinguish between light
and dark.

The only cause for absolute blindness would be the severing of the optical nerve from the brain. Absolute blind people don't see anything, not even black. Depending on the condition, the brain simply doesn't process any information from the eyes. It would be like trying to view the world using the palm of your hand as the organ of sight.

Plenty of FAQs available on the internet. Google---Use It.

 

[lavaheadache]

Originally posted by: ddviper
ive always wondered what blind people see, especially ones that may have had cancer and now dont have any phyiscal eyes at all (poor people ) do they see black? or do they see nothing?

(by nothing i mean close your eyes and turn your head. Sitck your finger out and point it at the monitor. Trying seeing with your finger, thats what i mean by nothiningness.)

Thats an incredible concept, I couldnt have decribed seeing nothing better

 

[Steffenm]

I guess we really can never know. The same way a man can never know exactly how it is to be a woman... surgery won't do it a 100%, or will it? We can never know. People who are born with no eyesight at all are known to have stronger senses than others. Like better hearing and smelling. I guess that is because all the brain acitivty and focus we use on eyesight will be used on our other senses. Eyesight would then be entirely gone and we would only know of it as a myth... somethiing that "everybody else has" and we would like to try. I feel more sorry for those (especially young people) who lose their eyesight during normal life, than those who have never had it. A shame for both of course, but you get my point. So don't you guys go out and play with fireworks!

 

[chukwaggin]

I think they see magenta or blue. That's what most capture cards see when you disconnect the s-video cable.

 

[walla]

does everyone (with normal vision) perceive color in the same way?

True, the visible spectrum has a basis in physics and can be defined in terms of wavelength. But what truly makes red, "red"? Perhaps that looks something completely different to you.

Without thinking of it much more than that, I realize its just one of those things you can't ever know.

 

[CycloWizard]

Originally posted by: ahurtt
I wonder if her hallucinations were analogous to the "phantom pains" that people feel who loose limbs?

Yeah, that's kind of what I was thinking. Some sort of residual 'memory'.

Originally posted by: Matthias99
Odds are they really incapable of "seeing" anything, and probably wouldn't see much even if you somehow fixed their eyes. The visual processing areas of their brain would be dramatically underdeveloped and less connected to the rest of their brain than in someone who could see from birth. The extra neurons would have probably been assimilated into their other senses (hearing, touch, etc.) Someone who could see but was then blinded might see "blackness", since that's what their brain "knows" to tell them when it's not getting any input from the rods and cones in the eyes. Interestingly, people like this still have visually-based dreams; the wiring's there in the brain, but there's no input going to it.

Asking what someone who has been blind since birth "sees" is a philosophical question (like one of those Zen riddles, eg. tree falling in forest, etc.). There's no good way to answer it in a definitive fashion.

:beer: As always, probably the best answer. Though now I'm curious as to how those blind from birth dream... I guess it would be just through the other senses?

Originally posted by: chukwaggin
I think they see magenta or blue. That's what most capture cards see when you disconnect the s-video cable.

LOL! :thumbsup:

Originally posted by: walla
does everyone (with normal vision) perceive color in the same way?

True, the visible spectrum has a basis in physics and can be defined in terms of wavelength. But what truly makes red, "red"? Perhaps that looks something completely different to you.

Without thinking of it much more than that, I realize its just one of those things you can't ever know.

I've read that bees see yellow as 'hot pink', though I think that's pretty hokey, as no human would ever really be able to quantify how a bee sees things. This is more of a philosophical question that we'll never know the answer to.

 

[firstimeposter]

A better question would be: Is it possible to describe colour to a person who has been born blind?

 

[Matthias99]

As always, probably the best answer. Though now I'm curious as to how those blind from birth dream... I guess it would be just through the other senses?

From the cursory coverage this was given in my neuroscience classes, yes.

 

[Gibsons]

Originally posted by: firstimeposter
A better question would be: Is it possible to describe colour to a person who has been born blind?

This is kind of like what's the sound of one hand clapping.

IIRC, there are some individuals who were blind from birth, but later gained sight through surgery. Supposedly it takes them a while to recognize objects that they already know. eg they know what a triangle is, but have to train in order to recognize it visually. Anyway, if anyone could attempt to answer the question, someone like that could.

 

[w00t]

Originally posted by: hondAS2ooo170
they c white

^^ he was blind he knows

 

[Peter]

I've spoken to a mate who is partially blind (after suffering a brain cancer that damaged the visual nerve). He's "lost" the upper left corner of his field of vision. He says there's just plain nothing there, not any color or black or white or whatever. Vision there is just totally gone. So I guess the answer is, you don't see - there's nothing there because there is no "there". Or somesuch.

 

[xSauronx]

Originally posted by: Peter
I've spoken to a mate who is partially blind (after suffering a brain cancer that damaged the visual nerve). He's "lost" the upper left corner of his field of vision. He says there's just plain nothing there, not any color or black or white or whatever. Vision there is just totally gone. So I guess the answer is, you don't see - there's nothing there because there is no "there". Or somesuch.

perhaps you could liken that to "what do people with normal vision see behind their head?"

nothing, it's not "there"

 

[Armitage]

Originally posted by: Peter
I've spoken to a mate who is partially blind (after suffering a brain cancer that damaged the visual nerve). He's "lost" the upper left corner of his field of vision. He says there's just plain nothing there, not any color or black or white or whatever. Vision there is just totally gone. So I guess the answer is, you don't see - there's nothing there because there is no "there". Or somesuch.

I've read some interesting articles about mapping out how the brain works by studying people who have had brain injuries. Some really interesting stuff on what it really means to see. There was stuff like you describe - people that couldn't "see" anything in the lower half of their visual field. People that couldn't "see" vertical lines, or such. They'd look at at letter 'L' and only see the horizontal part. Really interesting.

 

[xSauronx]

Originally posted by: Armitage

Originally posted by: Peter
I've spoken to a mate who is partially blind (after suffering a brain cancer that damaged the visual nerve). He's "lost" the upper left corner of his field of vision. He says there's just plain nothing there, not any color or black or white or whatever. Vision there is just totally gone. So I guess the answer is, you don't see - there's nothing there because there is no "there". Or somesuch.

I've read some interesting articles about mapping out how the brain works by studying people who have had brain injuries. Some really interesting stuff on what it really means to see. There was stuff like you describe - people that couldn't "see" anything in the lower half of their visual field. People that couldn't "see" vertical lines, or such. They'd look at at letter 'L' and only see the horizontal part. Really interesting.

linkage by any chance?

 

[RelaxTheMind]

I have a friend that has one eye (one glass eye). he grew up with partial site in that eye and sees nothing at all from that eye. no colors nothing. so bascially a cyclops.

"what if question"

A question that has always bothered me is that what if the color as my eyes see to be red is actually blue to everyone else or something like that. I wouldnt know because the color I see as red was called blue my whole life. I wonder if there are people that actually never figure this out.