Dreaming in Colour: Can Color-Blind People Dream in Color?

[Danger]

Hi, all. A weird question popped into my head this morning, after I swatted W across the snout because I dreamed that a wasp was bothering me. I know that it wasn't really a wasp because it was brilliant crimson. That reminded me of the olden days question of whether or not people dream in colour. I know that I certainly do, but it raised another question. Can someone who has been colour-blind (grey-scale vision only) his entire life dream in colour, or does it have to be something that has been experienced in waking life? I'm pretty sure, for instance, that I've never dreamed in UV or IR, which I figure is because I can't see them normally. Any colour-blind PFers care to enlighten me?

 

[DaveC426913]

"I'm pretty sure, for instance, that I've never dreamed in UV or IR, which I figure is because I can't see them normally."

Leave aside the colour blind fellow for a moment, and think about what it means to have sight beyond the normal human range.

Instead of dark flower petals or dark butterfly wings you would see light and dark patterns not noticeable otherwise. That's what seeing in UV would be. It doesn't mean you would see colours you've never seen before, it just means certain things (like wings or petals) that were dark before would now be brighter or would exhibit a variation that was invisible without your extended sight.

Whereas now, when you look at road pavement on a sunny day you see only black, with IR sensitivity, you would look at it and see it as a light grey.

Regardless of how your brain decides to interpret these new bright patches (i.e. if it assigned them colour) they are first simply a stimulation of the retina, and thus, rather than having a colour, are simply ... bright ... where before there was dark.

Does that put the idea of seeing extra colours in better perspective?

 

[Danger]

I see your point, Dave, but I'm not sure that I agree with it 100%. As a 'for instance', I can see patterns that a colour-blind person can't, which is the basis for most tests on the matter. If you had a red & green checkerboard, a r/g colour blind person would see it as solid brown. It doesn't seem that different to me than me not seeing the patterns that a honeybee does in a flower. I realize that it's a distinction between range of sensitivity and discrimination of frequencies, but the net result seems the same. On a similar, but different, note, one of my best friends hears low-range ultrasonics. The burglar alarm at Birk's used to irritate the hell out of him when he had to walk by at night. It wasn't a matter of it being louder than other noises; it was out of range for the rest of us. There are other people who can hear high and low pitches, but miss out on some mid-range. Either way, it's a form of 'deafness'.

 

[DaveC426913]

Well, that's true. I have an abnormally high range of hearing (apparently it's genetically related to asthma). I curl up in a ball and bleed from the ears when exposed to very high-pitched tones, while other people stand by and look at me askance.

 

[Tzemach]

Well, that's true. I have an abnormally high range of hearing (apparently it's genetically related to asthma). I curl up in a ball and bleed from the ears when exposed to very high-pitched tones, while other people stand by and look at me askance.

Now that is interesting I am asthmatic and I can hear the sound of bats, people used to tell me it couldn't happen because the bat's chirp is beyond the range of human hearing, but when I could point out that a bat was near they accepted that I could hear it. It is easier to hear the bat after he has passed (a great example of the Doppler effect).
If the condition is genetic it is possible that we have had a common ancestor somewhere.

 

[nrqed]

"
Whereas now, when you look at road pavement on a sunny day you see only black, with IR sensitivity, you would look at it and see it as a light grey.

Regardless of how your brain decides to interpret these new bright patches (i.e. if it assigned them colour) they are first simply a stimulation of the retina, and thus, rather than having a colour, are simply ... bright ... where before there was dark.

Does that put the idea of seeing extra colours in better perspective?

It's not clear to me at all that one would see the road as light grey. There is no telling what the sensation would be for such a brain. It could something so different in terms of perception that there would be no way to relate to anything we "normal humans" see.

For example, let's say that someone can not see blue at all but can see all the other wavelengths of the visible spectrum (above 500 nm, say). How could one describe what blue is like? There is no way to describe it in terms of grey or red or yellow and so on. It is qualitatively different.

Just my thoughts...

Very interesting thread, btw.

 

[Danger]

I can sympathize, Dave. While I don't hear higher notes than other people, the high end of the range that I can hear absolutely tortures me.
So, of course, W went and hung wind-chimes all over our balcony. At least now I don't feel so bad about swatting her.

 

[Q_Goest]

Hey Danger, Sorry you haven't gotten any colorblind folks answering this yet. Good question to research though. Somehow I doubt folks dream in colors that they've not seen.

I wonder in fact, if anyone can even IMAGINE a single color they've not seen. I can't, my imagination doesn't go there. I can't imagine a single color that I don't already have some reference for.

When I was a kid, I read a book by Edgar Rice Burrows (one of the Mars series) in which the heroine, John Carter, goes to Mars and sees colors he's never seen before. Of course, that's impossible, unless our minds somehow create colors they've never created before. The 'new' colors don't simply exist on another planet, the colors are all inside our head. We're limited to what we can see by the hardware (eyeballs, brains) that sees them, not by some limit on the wavelength.

So how can we force our brain to create a color? How can we force our imagination to create a new color we've never seen before, something that is not simply a shade of an existing color? To visualize a new color, our brain would have to do something it's never done before. I don't know why that would be impossible, but I bet it is.

 

[DaveC426913]

It's not clear to me at all that one would see the road as light grey. There is no telling what the sensation would be for such a brain. It could something so different in terms of perception that there would be no way to relate to anything we "normal humans" see.

Well, there's two elements here - I'm separating them.

The first element is that the retina is stimulated at all. By default, this will show up in the brain as something brighter (i.e. less black).

The second element is how the brain, once it has received this stimulus, decides to interpret it. Possibly a "different colour", possibly not.

Now that I think about it, we can look even closer.

We are already wired to receive and interpret signals from specific receptors in our retinae. We only have three: red green and blue. If we have IR or UV sensitivity, the question is how do we have it?

If IR radiation is stimulating our existing receptors (say, the red receptors are stimulated) then we will see more red (brighter, less black) where someone else might see black. In this case, the hot pavement, rather than looking black, would look dark red.

If we are sensitive to UV radiation becasue it is stimulating existing receptors (say, our blue receptors), we will see more blue (brighter, less black) where others will see darkness.


IF, on the other hand, we are sensitive to IR or UV becasue we have a whole new set of IR or UV-sensitive receptors in our eyes, well THEN we'd have no idea how to conceive of it.

 

[selfAdjoint]

I believe mammalian eyes can't have receptors that work in the IR or UV because
1) IR photons have too little energy to raise an electron to a higher energy level in the opsin molecule, which is the go-nogo condition for receiving a signal.

2)UV photons have enough energy to kick the electrons entirely free, essentially breaking the molecule.

This means there are good physical reasons that we see the spectrum we do.

 

[Danger]

I'd have to argue against item #2 there, Self. If UV ionizes retinal cells, nothing should be able to see it. It's been demonstrated that insects do (and possibly some other critters). I'm not sure why it isn't as harmful to them as it is to us, but the ionization energy in our cells can't be much different than theirs.

edit: I just realized that I never got around to clarifying the point of the question, which Q addressed directly, and why it's here instead of in Biology. The human brain is wired to accommodate colour vision, even if the eyes can't deliver it. It occurred to me that it might then be capable of 'imagining' it even without the optical stimulus. We are not, on the other hand, wired for other EM (as far as I know).

 

[eeka chu]

Interesting points.

Of coarse, younger kids can hear high pitched sounds. I dislike ultrasonic sounds also. Things like having the TV on, the hiss from the powersupply annoys me. A small general goods shop, not a million miles from me, was getting annoyed with having kids hanging around outside 'causing trouble' so they fitted an ultrasonic horn over the shop door because only the kids could really hear it. The council had them take it down for obvious reasons. I find I can usually hear better than other people but I think the biggest reason for that is that I spend a lot of time listening to music and trying to pick apart distortion profiles etc for electronics, so I'm used to concentrating on what I'm listening to. It's an important skill you need to appreciate things like Mozart's work, in which he'll have a few different things going on in simultaneously that you only 'see' when you get used to listening in a different way. Eventually the different voices end up adding a kind of depth to the music, you can start it playing and follow different pathways of instruments through it, listening to how they interact with the others.

Terry Pratchett discusses the idea of another colour in some of his books. I don't read them myself, but my family do. I think he mentions it in "The Colour Of Magic" and it's called Octarine.

The idea of our eyes not being able to see UV or IR is limited only by the light harvesting molecules in our retina. If they were changed, we would see those bandwidths. And as somone has already pointed out, they we appear to be the colours who's receptor sites they had been situated in. So if your new UV pigment was only located in the green cones, you'd see UV as a greeny hue on things. But that's an obvious point and nothing special.

Do colour blind people dream in colours? I suspect not very much. But it's like deafness, there are vary stages of it. And even the most extreme rarely extends right back to the circuitary of the brain, it's usually just a fault at the receptor side of things. Therefore, random / fluke firings of the colour neurons in a colour blind person's brain would probably allow them to see 'speckles' of colour occasionally but these wouldn't be assigned to objects, and so it'd be next to impossible for them to reference them to the names used by others. For instance, think about just before you go to sleep. Sometimes I see faint patterns of colour. That could be to activity on my retina, but it might also be due to neurons towards my brain.

But to give my conclusion, even if colour blind people do see these speckles and other traces from time to time, the fact that they can't assign them to objects (that they don't experience the colours of objects, and only perhaps some random noise), I would seriously doubt they'd dream in colour. Most colour blind people are only partially colour blind. I'm quite sure these guys dream the 'wrong' colours for objects.

You might be interested to know that the area in your brain where visual processing occurs has about 2.5 times the neuron density found elsewhere. To me that would seem to be an indicator that a huge amount of work needs doing on the input to filter it down to something understandable. For example, I would expect that at least some of these neurons are busy 'decoding' the edges of objects for shape recognition.

Expanding your visual depths of perception is a really interesting idea for me. We already do it to some extent with IR / UV cameras, X-rays and other such stuff. Jordie (or however it's spelt) for trek has his visor which let's him pickup the entire spectrum. The more I think about that idea, the cooler and cooler it becomes. If I had enough money, I'd really like to try that idea out. To make some sort of headset equipped with a multitude of CCD's for different bandwidths and to them feeding it down to some VR goggles or something like that.

The output of the CCD's could be processed into something my normal eyes could understand better, like IR cameras already do. You could then have lots of different ways of sweeping to different bandwidths to detect things. For instance, you could have the hideously limited bandwidth of our own eyes sweeping from one end of the available spectral output to the other over a few seconds; you might actually be able to do this quite quickly once the person gets used to it because certain types of radiation will behave differently to others, allowing them to be distinguished quickly. You may even be able to superimpose one spectrum on another, UV onto green for instance. Again, the differences in radiation behavior might allow you to tell normal green light and UV green light apart, even though they both look the same colour to you.

Alternatively, you could have event detectors preprocessing the output of the CCDs and then feeding you the most relevant. So that would work maybe by watching for bright emitters. If the headset detects a bright UV source, it switches you to that channel.

Lots of different ideas.

What seems interesting to me about this is the idea of leaving the headset on for prolonged lengths of time. We'd suddenly be seeing the universe in something closer to '3D' (if you like). All the information we were previously missing would start showing up. Perhaps a lot of it would just be junk and not much use. But perhaps some of it would present possible new scientific or engineering solutions. Previously, these might have been missed because no one thought to look for them, and needed a special instrument to do so. With your headset on though, you could walk around looking and anything and everything to see if there's anything funny happening. If there's one thing the human brain is great at, it's spotting patterns and things that are unique to it.

I guess I'll probably get some stick for this but... this kind of thinking is where I begin seeing a practical use for hallucinogens. Granted, what you actually see on a trip probably isn't of much use directly, but it allows you compare and contrast operations of the brain by providing an alternative to the normal. A lot of inventions are just linear development of empirically gained knowledge; memories. A trip is a like rolling a dice to some degree, it produces a series of 'off the path' alternatives. You go crazy when you start believing all those alternatives. But if you're intelligent and have at least some will power you can sort through those alternatives and 'viability' check them. The intensity of the sensual demonstration of things being entirely 'wrong' to the normal I think is also useful because, again not due directly to the content of the experience, it helps you really, truly appreciate that your senses are less than perfect and just how much you trust in everything they're telling you, how much of a part of you as a consciousness they are and how pretty much everything you base your world around relies on them.

Of coarse, I don't recommend you try this yourself unless it's totally your own decision and something you're enthusiatic about (for the right reasons). And even then, a lot of these are class A drugs. But there are a lot more uses to hallucinogens than you ever hear about. Most of them are also entirely none addictive (I know from direct personal experience that a MacDonald's Flurry is more addictive than magic mushrooms are. I haven't heard of a single person, literally, ever becoming addicted to LSD / magic mushrooms etc) and are virtually impossible to overdose with (you have to eat tens, hundreds or thousands of times more than the quantity you actually need). Just because the government has decided to make something a class A drug it most definately doesn't mean they know precisely what they're talking about, it's just numbers on paper to the people actually passing those laws.

 

[selfAdjoint]

I'd have to argue against item #2 there, Self. If UV ionizes retinal cells, nothing should be able to see it. It's been demonstrated that insects do (and possibly some other critters). I'm not sure why it isn't as harmful to them as it is to us, but the ionization energy in our cells can't be much different than theirs.

edit: I just realized that I never got around to clarifying the point of the question, which Q addressed directly, and why it's here instead of in Biology. The human brain is wired to accommodate colour vision, even if the eyes can't deliver it. It occurred to me that it might then be capable of 'imagining' it even without the optical stimulus. We are not, on the other hand, wired for other EM (as far as I know).

Yes I am aware of the insect ability to see UV. I don't know how they protect their retinas, perhaps the "fly-eye" evolutionary technology plays some part. But the point about UV and the mamalian retina is solid, think what UV does to unpigmented skin!

And your argument about imagining color even when we don't see it is good. I think our brains have an upper level of analysis for colors and language both, that can produce sensations without being stimulated by the sensory level. I don't "dream in color" but I sometimes see colored objects in my dreams. Usually exaggerated saturations of red or bright blue. You could say I only dream a color when a color plays a part in whatever story I am telling myself in the dream.

 

[matthew baird]

I guess I'll probably get some stick for this but... this kind of thinking is where I begin seeing a practical use for hallucinogens. Granted, what you actually see on a trip probably isn't of much use directly, but it allows you compare and contrast operations of the brain by providing an alternative to the normal.

Hehehe I must say that my experiences with the magic mush definitely open your mind to other alternatives. I seemed to focus on my thoughts much more than what I was seeing (although what I was seeing was incredible). I also think the effects of mush on me are different than other who experienced them with me. Everyone else just sits around being lazy and or stuck to the couch claiming they cannot move...lol..meanwhile I can act as nothing is different or wrong. If it weren't for my pupils being overly dialated no one can tell I'm not sober. From my personal experiences, mush really helped me to see things from other perspectives, and really fed me more passion to learn about this world (especially when I had experiences that were isolated out in nature, for me any man made things around at this time seem to ruin it somewhat)

 

[Danger]

Jordie (or however it's spelt) for trek has his visor which let's him pickup the entire spectrum. The more I think about that idea, the cooler and cooler it becomes. If I had enough money, I'd really like to try that idea out. To make some sort of headset equipped with a multitude of CCD's for different bandwidths and to them feeding it down to some VR goggles or something like that.

It's spelled 'Geordi'. We're probably closer to something like that than most people think. Remember that his VISOR (it was an acronym for something) fed directly into his visual cortex. Researchers are already doing that on human subjects, although I believe that the results are still rather like a very low-quality silouette effect. It's been a while since I saw anything about it. (As a side note: Although they soon began ignoring it, the original predicament was that it caused him extreme pain. For the first few episodes, he took it off whenever possible. His choice was to be comfortable, or to see.) What you refer to is more of a 'transformer' than an extended sense. Regardless of what frequency you are scanning, it's still being converted to a normal 'human vision' one and processed as such by the eyes. You aren't really experiencing a new sensation.
I don't quite agree with usefulness of hallucinogens for the purpose that you propose, although I have no sound basis for disputing it. It just seems to me that due to the nature of such things, you wouldn't be able to excercise the kind of control over signal processing that you mention.

Yes I am aware of the insect ability to see UV. I don't know how they protect their retinas, perhaps the "fly-eye" evolutionary technology plays some part. But the point about UV and the mamalian retina is solid, think what UV does to unpigmented skin!

Maybe all of those multiple refractions from the compound eyes reduce the energy (even down-shift the wavelength) to something harmless. Any entymologists around? As for the effect on ours, and skin... I pretty much never sunburn, but I'm severely photophobic. It's primarily UV that hurts, although any bright light (which to me is normal room lighting) is somewhat painful. I'm quite comfortable reading by the light from the TV, although at my advanced age I now have to tilt the page to get the maximum amount of that light.

I only dream a color when a color plays a part in whatever story I am telling myself in the dream.

I just find that weird. I've never understood why someone would dream in B&W. Maybe it has something to do with the time-compression effect, wherein a dream that lasts ten minutes can cover several hours of subjective activity. There might not be enough bandwidth in some people to carry a colour signal. (I have more than enough, given my ADD. )

 

[Danger]

Oh, hi Matthew. You sneaked in while I was typing. Perhaps the mushrooms are a different sort of beast. I was thinking along the lines of acid, which didn't seem to leave a lot of control to the user.

 

[eeka chu]

Hehehe I must say that my experiences with the magic mush definitely open your mind to other alternatives. I seemed to focus on my thoughts much more than what I was seeing (although what I was seeing was incredible). I also think the effects of mush on me are different than other who experienced them with me. Everyone else just sits around being lazy and or stuck to the couch claiming they cannot move...lol..meanwhile I can act as nothing is different or wrong. If it weren't for my pupils being overly dialated no one can tell I'm not sober. From my personal experiences, mush really helped me to see things from other perspectives, and really fed me more passion to learn about this world (especially when I had experiences that were isolated out in nature, for me any man made things around at this time seem to ruin it somewhat)

I like to lie, sit or otherwise be nice and comfy and still, like on my bed. I also like being by myself, so I don't have to worry about what other people will be thinking.

I remember my first trip, which was with Salvia Divinorum. I'd seen the walls of the room I was in as 2D surfaces, like they would be in a level designer for a computer game or CAD package. For a little while after I always looked at walls and thought, perhaps this is just a skin and I was kind of tempted to press my hand against them every now and again just to think about it some more. And to an extent you can argue that the thing you're seeing and experiencing as a wall isn't actually there, it's just what your senses are telling you the energy & mass is like; arguably, there is no brick and it's not beige, it's just a brick like pocket of energy & mass that happens to be emitting those wavelengths. That's what my main positive view is on hallucinogens, that it makes you think about things like that. Constantly thinking "all walls are hollow" is the crazy route, but thinking "perhaps it's not precisely what it looks like to me" is where I think they have some use. And it's much more tactile and substantial than just reading into things like quantum mechanics, because you've literally seen and felt it.

It's spelled 'Geordi'. We're probably closer to something like that than most people think. Remember that his VISOR (it
[snip]

I thought I could sneak that one by without complicating the discussion with it, but I see I've met someone who likes trek too. Some would say I like it too much, but I haven't bought any trek outfit to wear... yet. Maybe when, one day, I get married I'll start buying them just to scare my future wife.

I was just watching the first series and the special features bit in which Geordi (I thought it was that but for some reason went with J) talks about the idea of the visor (which, indeedy, is an acronym for some stupid long sentence. I hate acronyms), the idea and how he wanted to see it.

Even connecting that visor directly to his cortex, I still think he'd probably see the normal range of colours humans do, maybe even less if it wasn't a perfect connection. I would strongly suspect that 99% of the neurons relating to things like colours are preset in our genes as opposed to developing depending on the data they're fed from our optical nerves. I think new bandwidths would be more likely to show up in the normal colour range but as strange effects within them, like hues around things maybe.

I think the only way you'd start seeing new colours is if you were to start messing around with the genes belonging right in the occipital cortex that control that particular area of development. Maybe you could implement something manually on a tissue level but I doubt many people would volunteer for that. But then, to test the gene idea you'd have to raise someone who the subject of a test, since you'll probably at least need them to be able to describe things to you.

I'm majorly into neural interfaces and have heard about these kinds of ideas. One was to place an electrode array on the person's tongue with 64, or something like that, contact on it that were hooked up to a CCD. The person could just about make out movement and things like that but the level of resolution was terrible, enough that they'd still qualify as blind even with it. I think they were trying to make the point that the people could visualise what was happening to some extent, not just feel it... but that's loose ground.

Here's an article about a blinded guy with an outline like view provided by a replacement eye...

http://news.bbc.co.uk/1/hi/sci/tech/606938.stm

There's a big conference thing in the US based around neural interfacing that I hope to attend this year. But it means flying all the way over from the UK, which is pretty extreme consider it's not my job and I'm not actually a student.

With the insect retina and UV, the reason they don't get UV burns will just be different absorbers as the light harvesting complexes and / or pigments in the tissue it's self, just the same way that black people don't burn as easily as white people. I'm sure if we had super strength absorbers we could see gamma rays (I'm getting pictures of someone looking at the sun through binoculars and light shining out the back of their head ).

I dream in colour. Dreams are highly focused for me, I expect they are for a lot of people. That the things we remember are only really the points that we were directly paying attention to.

I've experimented with lucid dreaming a little. The best way I've found to have lucid dreams is just to stay in bed for 12 hours plus. After about 9 or 10 you'll start waking up every 30 to 60 minutes and this process of constantly drifting into and out of sleep seems like the easiest way to catch a dream in your memory. I remember one very clear dream in which I did notice something happening away from the focus of the dream and it was two or three people standing beside me, on the edge of my view. Parts of the people were a.) missing b.) not fully formed c.) constantly reforming and 'defining' themselves d.) flickering a little or blurred somehow, distorted. As an example, I could see someone's head but their face didn't really have a photographic quality to it, it was just roughly right and changed a bit as time went by. This I attribute to my not having actually seen these people in reality, or if I did, not paying much attention to them. As a result, my brain is lacking the information to spontaneously draw an exact copy of them (I doubt it can do this even with people we know very well), so I was seeing a rough representation of what a person should look like.

I feel kind of lucky to have seen that happening. I think I've seen it in other dreams as well. It's almost like my mind's view of things while I'm up and about, that it's approximately what things look like and only collecting information about the interesting parts of my sensory experience. Even though pieces of these people seemed wrong or missing, while other bits seemed more correct, I could still identify them as people.

I've also had at least one dream in which I very specifically got the feeling that I was dreaming. I was standing in a shopping center and it started to rain, and it seemed wrong. Although, that could just be like an April shower, when it's sunny and then starts to rain for no particular reason (a speciality of the UK), usually producing a similar feeling. I woke up about 5 - 10s later (in dream time).

It just seems to me that due to the nature of such things, you wouldn't be able to excercise the kind of control over signal processing that you mention.

I would agree that'd be nice if it occurred in a more controllable manner, that we could just mess around with specific fragments of our consciousness to see what happened. But there isn't much out there that will allow that due to the very fact that our brain uses only a handful of neurotransmitters for everything it does.

I'm not trying to say that tripping is a great idea for kids to try out or that it's the correct way to conduct scientific experiments, but just that the different view it gives you of the world can help you understand or learn a bit more about yourself (that sounds very hippyesque). For example, whilst tripping, an otherwise boring and none descript object will have some property of it changed, and it suddenly becomes something you take notice of. The flipside of this, when not tripping, is that bright advertisements grab our attention more than dull ones. It's just like the other side of the coin, I can take something totally unworthy of my attention and it instantly becomes interesting because some change in it's normal attributes has made it unique to my memory (It's as if my memory recognises the object, loads my memory of it, compares it to what I'm experiencing and grants it a level of wothyness for further investigation based on the amount of difference between the two). For me, something like that rams home the point (real hard) that our brains have huge amounts of compression and multiplexing on their input before they ever reach our conscious level. It's the kind of structure that any well designed system that has to operate in a dynamic environment utilises. We don't need to be paying attention to most of what we experience to get by in normal life.

Hallucinogens are in a totally different domain to other drugs. I would go as far as to say they're almost not comparable. They produce artificial changes in your body, but that's about where the similarities stop for me (and most other trippers). I'm happy to eat magic mushrooms but would never bother with things like extacy or any of the equally horrible junk you get in clubs.

 

[Danger]

(I'm getting pictures of someone looking at the sun through binoculars and light shining out the back of their head ).

You have some very interesting thoughts there. Thanks for the video link.

I've experimented (when I had time for such things) with lucid dreaming. My objective, though, was to control what happened in the dream. It's surprisingly easy once you realize that you're dreaming.

 

[larkspur]

Here is a neat site that provides a filter that allows you to view a web page like a colorblind person views it.
http://colorfilter.wickline.org/"

 

[eeka chu]

Here is a neat site that provides a filter that allows you to view a web page like a colorblind person views it.
http://colorfilter.wickline.org/"

Nice find!

 

[moonchild]

People who see color do not necessarily dream color in the same way people who do not see color can never be without the faculty of summoning color to their imagination. One might be without sight but still perceive shape and possesses an aptitude for interpreting its geometry but more from the power of the intellect than from actual sense. Remember that organisms capable of contemplation can determine their reality relative to the power of their minds and in the way that their organs have been designed to facilitate that process. In this context, an organism with weaker mental powers will not produce ideas in terms that will demonstrate any kind of creative thought, rather, perceiving things will not have any effect besides what is absorbed. In a more receptive brain, the aptitude for retention and transmission and creation are far more powerful, and so if one dreams in color, or perceives things it ought not to perceive conventionally, because it lacks the prerequisite organs (eyes, nose, etc), then accordingly the conclusion for doing so would be in the acuity of the intellect not because of experience or a lack thereof.

 

[redargon]

So do blind people dream? I mean people that were blind from birth and have never experienced colour or light. I think that surely they must and what they "see" in their dreams is how they "see" in real life, how they experience real life. Probably through sound and touch. I think a colourblind person, in the same way, will just dream in whichever way they experience normal life. That's my 2 cents.

 

[DaveC426913]

So do blind people dream? I mean people that were blind from birth and have never experienced colour or light. I think that surely they must and what they "see" in their dreams is how they "see" in real life, how they experience real life. Probably through sound and touch. I think a colourblind person, in the same way, will just dream in whichever way they experience normal life. That's my 2 cents.

Read Oliver Sacks' 'Island of the ColorBlind'

IIRC, people who are blind since birth do not dream pictures. People who have had sight do.