The huge problem is that we lack vocabulary to talk about unique qualia. Our words come from talking to other people and if nobody around us has the same qualia as we are, nobody gave us a word.
At the moment I'm learning to distinguish colors better via an Anki deck. I use the CSS color name definition. Seeing the difference between navy and midnightblue is still hard for me but I'm confident that I can learn it with practice. Some day I will hopefully even be able to tell apart snow from floralwhite.
I like the particular deck and if someone wants to train their color perception I'm happy to share it. It's build in a way that you get progressively more difficult decisions and provides years of fun at 5 new cards per day.
I would also like to create a deck to train sound perception. Does anyone know of a good tool that can automatically produce sound files with a specific pitch for pitch training? At best a tool that can be used via the command line.
From time to time I hear about people going to their physician when they realise something is off about their body accidentally when someone mentions something that makes them realise they are unusual in some respect. I am then often surprised that these people report the physician saying something along the lines of the phenomenon being well documented and benign.
Personally, I have a couple of tones in my ears for the first two decades of my life without realising that tinnitus is unusual and I do not know what absolute silence is. Ironically, I also have exceptionally great sensitivity to quiet sounds. And, again ironically, I have trouble understanding human speech when there is background noise.
I was surprised when I first moved in with roommates to see how one of them and some of the neighbours were just absolutely noisy. After some inquiry I realised that they are just not as bothered by noise as I am. Oh and apparently they are unable to hear as sensitively as I do.
Further, I hate background music above a certain, quite low, threshhold if I want to maintain a conversation. Other people's conversations are similarly challenging. These facts do explain quite nicely why so many people like clubs, bars or pubs but I do not.
There are plenty of these little things and it maddens me every time I see psychological studies or policy assuming homogenity in the human population. We are different in so many often quantifiable ways. I am not sure yet of the practical use of these little facts but I am sure there is.
The presence of an object (or even my own finger) near the center of my forehead causes a tingling sensation, which can even shift directions (but still, always centered on my forehead) as the object moves.
I suspect I'm a supertaster. I'm extremely sensitive to bitter flavors, to the point where I can't eat olives or drink beer or coffee. It's torture for me. My father always complained that I put too much sugar into the coffee I made for him, but whenever I tested it I couldn't imagine how anyone was able to stand it without at least four spoonfuls. Every single person I know will swear to me that bell peppers are sweet, but in my mouth they taste a murderous bitter. Celery is out of the question for the same reason.
Both my eyes may from time to time perceive colors in a different way. When they do, one would see everything in more greenish-blue hues, the other in more red-yellowish hues. It's often the case when I closed one eye for a moment, or when that eye was on the pillow side after resting. So I assume it's either temperature-related, or simply that one of my eyes' cone cells were too exposed to, say, red, because of red light filtering through my closed eyelid, and therefore were less sensitive to it afterwards.
(I scored 3 on http://www.apartmenttherapy.com/how-well-do-you-see-color-173018)
I think I have qualia associated with small numbers.
The closest analogy I can think of is "butterflies in your stomach, but with a pitch". I say pitch not because it's auditory (it's not), but because it seems to be the same feeling but higher or lower for different numbers (not in intensity, but in ... pitch).
I think that I lack a precise sense of relative pitch over time - as in I can only easily compare tones that are simultaneous or directly one after the other. Give me three tones where pitch first, say, raises and then lowers again, unless they are either identical or a good octave apart I have a hard time telling if the first or third is higher in pitch.
I have a friend who was surprised to discover the concept of a "lucid dream". It turns out all of his dreams are lucid and he assumed it's the same for all people.
A psychological experience I have (albeit very rarely). I suddenly realize that I am really me. In comparison, all the rest of life feels like watching a movie in which I am just one of the characters. Sorry if it came out confusing, it's a bit hard to explain! With age the occurrence seem to have become even rarer (I don't remember when I had the last one but it might have been over 10 years ago).
When I am in familiar surroundings, I feel like I can very easily go to the next room or out of the building at all, and it's a bit like I have already gone there. I don't mean any kind of 'out of body experience', just that there's some fuzziness in my mind about where exactly I am. In contrast, when I got stuck in an airport halfway across North America, with some uncertainty as to whether I would reach my destination the next day or the day after that, I felt very clearly that I was exactly bound by my body. The world began, sharply, just outside my eyes. Has anybody felt the same?
Ability to distinguish taste varies quite a bit, with some people only really tasting strong flavors.
I can distinguish patterns in higher tones in music better than low tones. All drum and bass music sounds indistinguishable to me.
Vocal patterns have a bigger influence on interpersonal communication than generally assumed. Interruption vs waiting, deeper vs higher tone voices, pace, non-word vocalization, physical expressiveness (hands, face, body) etc. Some people find certain patterns attractive/aversive and this influences how seriously you take the speaker.
I have two such perceptions which may or may not be related.
Since I am very young every now and then I have had an temporary alternation of vision. Suddenly everything looks much farther away than it is and as if I'm looking through a tunnel with dark and/or blurry sides. When I was young, maybe 12 years old and told my parents this the thought I were tired. But I wasn't. It happens during the day. It is distracting but it goes away after closing the eyes for some time and resting. Or whatever. Doesn't stay longer than an hour.
The other thing is a highte...
Human genetic diversity is huge and still increasing quickly:
http://www.sciencedaily.com/releases/2012/11/121128132259.htm
I bet half of the 'deleterious' mutations mentioned in the article relate to more or less unusual experiences.
Still ongoing? Of course. Huge? Not at all. We had a population bottleneck a few thousands of years ago, and our diversity suffered as a consequence. An extended family of chimpanzees displays more genetic variation than the entire human species:
In his recent excellent blog post, Yvain discusses a few "universal" (commonplace) human experiences that many people never notice they don't have, such as the ability to smell, see some colors, see mental pictures, and feel emotions. I was reminded of a longstanding argument I had with a friend. She always insisted that she would rather be blind than deaf. I could not understand how that was possible, since the visual world is so much richer and more interesting. We later found out that I can see an order of magnitude more colors than she can, but have subpar ability to distinguish tones. And I thought she was just being a contrarian for its own sake. I thought the experience of that many colors was universal, and had rarely seen evidence that challenged that belief.
More seriously, a good friend of mine did not realize he suffered from a serious genetic disorder that caused him extreme body pain and terrible headaches whenever he became tired or dehydrated for the first three decades of his life. He thought everyone felt that way, but considered it whiny to talk about it. He almost never mentioned it, and never realized what it was, until <bragging> I noticed how tense his expressions became when he got tired, asked him about it, then put it together with some other unusual physical experiences I knew he had </bragging>
This got me thinking about when it is likely we might be having unusual sensory experiences and not realize for long periods of time. I am calling these "secretly secret experiences." Here are the factors that might increase the likelihood of having a secretly secret experience.
1) When they are rarely consciously mentally examined: experiences such as the ability to distinguish subtle differences in shades of color are tested occasionally (when choosing paint or ripe fruit), but few people besides interior decorators think about how good their shade-distinguishing skills are. Others include that feeling of being in different moods or mental states, breathing, sensing commonly-sensed things (the look of roads or the sound of voices, etc.) Most of the examples from the blog post fall under this category. People might not notice that they over- or under-experience or differently experience such feelings, relative to others.
2) When they are rarely discussed in everyday life: If my experience of pooping feels very different from other peoples' I may never know, because I don't discuss the experience in detail with anyone. If people talked about their experiences, I would probably notice if mine didn't match up, but that's unlikely to happen. The same might apply for other experiences that are taboo to discuss, such as masturbation, sex (in some cultures), anything considered gross or unhygienic, or socially awkward experiences (in some cultures).
3) When there is social pressure to experience something a certain way: it may be socially dangerous to admit you don't find members of the opposite sex attractive, or you didn't enjoy The Godfather or whatever. Depending on your sensitivity to social pressure (see 4) and the strength of the pressure, this could lead to unawareness about true rare preferences.
4) Sensitivity to external influences: Some people pick up on social cues more easily than others. Some notice social norms more readily, and some seem more or less willing to violate some norms (partly because of how well they perceive them, plus some other factors). I can imagine that a deeply autistic person might be influenced far less by mainstream descriptions of different experiences. Exceptionally socially attuned people might (perhaps) take social influences to heart and be less able to distinguish their own from those they know about.
5) When skills are redundant or you have good substitutes: For example, if we live in a world with only fish and mammals, and all mammals are brown and warm and all fish are cold and silver, you might never notice that you can't feel temperature because you are still a perfectly good mammal and fish distinguisher. In the real world, it's harder to find clear examples, but I can think of substitutes for color-sightedness such as shade and textural cues that increase the likelihood of a color-blind person not realizing zir blindness. Similarly, empathy and social adeptness may increase someone's ability both to mask that ze is having a different experience than others, and the likelihood that ze will believe all others are good at hiding a different experience than the one they portray openly.
What else can people think of?
Special thanks to JT for his feedback and for letting me share his story.