Tuesday, March 10, 2009

Mental Relativity

I've been thinking about color perception lately. It's hard for me to even imagine being colorblind! What is that experience like?

If you suffer from a more common form of colorblindness, you won't be able to make out the symbols in the above picture. In an example like this, I've always assumed that a colorblind person must just see brownish red everywhere.

Then again, maybe he or she just sees green. Maybe gray. Then I got to wonderin'...

Color wavelengths are real and measurable. When I see a red barn, you see a red barn, and we can agree on a color because we're sensing the same wavelength. But what if I switched brains with yours and discovered that your perception of red is more like my perception of green! Because we can't swap each others sensing organs, we'll never know if our consensus about a stimulus is exacting or if we're thinking analogously.

I wonder what kind of mental relativity is at play. How different are we, really, from one another, and how can we ever know?


SuiginChou said...

I had this thought (and still do) all the time as a kid. I asked Mr. Hauptmann about it in the 9th grade. He (being colorblind) had naturally given it a lot of thought since his own childhood, and he said it's one of those things that can never be scientifically proven in that any attempts to link empirical evidence with perception are always subject to criticism from those who would argue, "Well how do you know?" You never "know" anything in science, or in life for that matter: you infer. You draw conclusions based on the evidence. We are by nature creatures who take correlations to be causations. That is to say, there is technically no way to ever prove causation because the person who chooses to believe that is merely correlation of the most absurd measure cannot be made wrong by the evidence: he has already "made" the evidence wrong in his own mind. :)

Sorry, I'm babbling. Back to the point: Mr. Hauptmann and I talked about this, and (I don't remember which of us said it, but) we discussed how even if you were to take my brain and put it with your eyes, and even if I was to then see that your world looked different to me (e.g. red was blue, green was yellow, brown was white), there would be a great deal of scientific skepticism:
- did you line the wiring up correctly? (i.e. the J-optic nerve to the R-optic chiasm) or is the wiring maybe off in such a way as to distort the signal, just as any cable repairman could tell you about if a cable is cut in half and then crudely reattached?
- did Ryan's brain change during the transplantation as a result of the transplantation, and thus it's his own brain which is now misinterpreting normal colors and parsing them off as Jay being the one who had had bizarro vision?
- same as above but with Jay's eyes instead of Ryan's brain

On and on and on it goes. To give you an obvious example (which would naturally be caught quite quickly, so it's not the sort of thing we'd expect to REALLY botch the experiment, but still!), let's say that during the surgery your eyes got a little bit of blood in them and so when my brain was turned back on inside your head I reported to the scientists that Jay's hues were all the same as mine with respect to one another but that his overall absolute values for his hues were a little too high in their Red hexadecimal value, i.e. "it's like I'm looking at the world through rose-colored lenses -- SERIOUSLY!". Let's say this happened. And let's suppose the scientists did NOT catch it. They would conclude, "Wow! Human vision *IS* relative! Wow! Jay sees things redder! Ryan sees things bluer! Wow!" Even though we see things exactly the same but the imperfect surgery created a false positive.

So anyway!

Is it cool to consider? Yeah! :) I still do all the time. (I'd say I think about it at least once every one to two months. Something'll set it off. The relativity of human sensation is one of the most fascinating things to me, perhaps because I love biology, physics, and a little bit of philosophy and perception is one thing which brings all three disciplines together.) But could you really ever hope to get anywhere with it? No, probably not.

Other fun food for thought, since (duh) this ought not to be restricted to just seeing. ;D I'll save it for the next reply, okay?

SuiginChou said...

More fun food for thought:

Q1. Ask the same question you did for sight but apply it to the other senses. For example, is my hot your cold? Is my soft your rough? Is my bright your dark? Et cetera.

Q2. What if a person's brain (during development) links the quote unquote "incorrect" organ to the "incorrect" part of the brain? So that, for example, people's eyes translate EM radiation into what is perceived inside the person's head as sound? (so that the higher the wavelength, the higher the pitch, i.e. violets sound higher pitched, reds sound lower pitched) And what if they see colors as a result of the compressed and rarefacted air? so that high dB is violet and low dB is red? You say, "But Ryan! We know this isn't possible!" But we don't know, do we? ;D Because after all, we teach a child from a young age, without really knowing what is happening inside of his own unique brain, "this goes with this, that with that." We tell a child that an apple has a property called color and its color is red, etc. So a child may learn to call what he sees with his eyes as red EM light and hears in his head as low-pitched sounds "red," and teachers will tell him, "Good! Very good!" And he'll learn to call bright intensely red lights in his head "loud, low-pitched sounds" and he'll call dim, barely visible purple lights "high-pitched whines." He really is 'hearing' with his ears, because the human ear's function is independent of human perception: it translates compressed and rarefacted physical media into "sound." But what sound is depends entirely on the individual, doesn't it? :D :D :D Just like the colorblind boy who sees blue apples but they're a slightly different shade of blue that his mummy and daddy call "red" so he learns to call it "red" too, so too could this be true. :)

Q3. Ask yourself if other people may have fewer or more numerous degrees to which their five senses operate within the realm of measured scientific thresholds. What I mean by this is:
- we are taught that for most people the phenomenon of flavour is actually determined 90% in part by smell and only 10% by taste-proper. This is because most people can relate to this when they have a stuffed-up nose and everything tastes more bland.
- and indeed! maybe everything does taste more bland for almost everyone alive!
- but what if, for some reason, some individuals' sense of taste-proper is really much stronger than science gives credit for? so that even though foods taste worse to them when they have a cold, it's only 80% flavour lost instead of 90%? This would be hard to tell apart because it's subjective and otherwise too close to tell apart without an objective measure of some kind.
- or what if one person "tastes" things 100x more intensely than others, but his thresholds are the same as ours? in other words, like us, he can't tell the difference in taste between pure water and water with x% salt. And like us, he can't tell the difference between water with y% salt and completely saturated saltwater. They're just too close to tell apart for either of us, let's say. But what if for him, the axis is pure water=0 and saturated saltwater=1000000 (in terms of experienced intensity), but for us the axis is only from 0 to 10000? Could this not possibly explain why some people think food is too salty while others think it is not salty enough? (etc etc) That we human beings all in unity strive to taste food which ranks at around a 6000 to our brains, and so for most people that might be 6000/10000 (rather salty) but for this individual it's also 6000 but out of 100000000 or more (so barely salty at all), thus making him seemingly "unable to tolerate much salt" when in fact he tolerates the same MENTAL amount of "saltiness" as the rest of us?

I could go on for hours, but need to finish my lunch. :) The point is, I love thinking about the relativity of human perception. Heck, I thought of you and of binocular vision JUST YESTERDAY when I saw some (bullshit) video about how much we rely on our binocular setup for 3D perception. (Yes, I agree that it probably lends some function; NO, I have NEVER EVER personally found that the world suddenly changes or looks different at all when I close one eye vs. having both eyes open, the ONLY ONLY ONLY difference being that both eyes open = stuff's straight ahead of me, but one or the other eye open alone = shift it 2 cm to the left or 2 cm to the right. GEE, I WONDER WHY. :p :))

We should totally talk about this for hours and hours if you want. :) Or ... not, if you don't want to. But I think this stuff is really quite cool. If, as Mr. Hauptmann scolded me all those years ago ;D , ultimately kinda fruitless.

SuiginChou said...

In case it wasn't clear (sorry!), in my Q2 example, I was saying this:

(1) Eyes are designed to translate EM radiation into a signal. Period.

(2) But how that signal is decoded depends entirely on where it winds up in the cortex.

For example, a phone internet signal going into a phone modem port makes magic happen, but a phone internet signal decoded by a housephone sounds like screeches and chirps.

(3) Education in early childhood is concerned simply with getting children to learn the labels that are already in place, i.e. there is such a thing as colors that we see with our eyes, the colors are red, blue, yellow, green, etc, apples are red, etc.

(4) The success or failure of #3 has little to do with whether the phone modem or the housephone is what receives the internet signal: it has only to do with how the child generates back an output.

In other words, if (theoretically) the child could creepily chirp and whistle back into the receiver of the phone and insodoing create a signal which could be interpreted by the ISP as "websurfing", then the child could surf the internet just by hearing the noises and emitting the chirps.

(5) And all I was trying to say was that maybe children *DO* do these "creepy" things but they do it in a way which seems perfectly normal from our own frame of reference! i.e. maybe a child really does look at an apple with his eyes, and his eyes detect the light allowing him to tell that it is red, round, and small; but in his brain, the eye's signals were converted as follows:
- the child's red --> what I would normally call "low-pitch sound"
- the child's round --> what I would normally call "sustained pitch" (rather than staccato or some such)
- the child's small --> what I would normally call "very few instruments generating the sound, e.g. a soloist is small vs an orchestra is large"

And so the child is really experiencing for his sense of vision what I think of as my sense of hearing, but I'll never know and neither will he: because when asked to describe the apple, he will correctly report "it is red, round, and small" and he will be given a sticker and a pat on the head. He will correctly report "I can no longer see it when I close my eyes," even though from my perspective what he really means to say is "I can no longer hear it."

Anyway ... I'm going on and on, aren't I? :) Gotta go!!

Jay said...

I'm glad to see you know exactly what I'm talking about. I was afraid I didn't do a good job explaining myself. It's a really kind of fun, mind-bending thought experiment, isn't it? Like the "maybe we're in the matrix" argument and just as insolvable. Have you talked in any of your medical classes about the phenomena that I believe is called synecdoche? Wherein patients report a strange mixture of senses, like being seeing colors in music, or tasting sounds? I've seen a couple really interesting discovery programs about it, but a quick google search only brought up hits of a movie about Synecdoche, NY.

SuiginChou said...

Yes, we did. I'd heard about it previously, but we did discuss it in school.

And these discussions certainly do share in common with Matrix and The Man theories of existence the element of intractability. For every proof that we're not in the Matrix, a person may say "but maybe that's just what the machines want you to believe?" e.g. "Why haven't they killed me yet for having these thoughts? Heck, why'd they even let me see the film in the first place?" --> "Well because! They wanted you to see it as an entertaining piece of fiction and insodoing to embed it in your brain as not really being real!" "But what about you? You think it's real, don't you? So how come they haven't killed you yet?" At which point the maniac may be likely to kill you if his mind instructs him, "Oh shit! They're on to me! Ryan is probably one of the Agents!!"