Saturday, December 6, 2008

Living in a world of muted shades

Colour blindness. In most cases, it's an inelegant and inaccurate term - certainly not very PC (that is, politically correct, not Progressive Conservative or President's Choice). In general, the term colour blindness is used to describe some form of colour deficiency. Affected persons usually have difficulty distinguishing between certain colours, but still retain some level of colour vision. The degree of impairment varies from person to person, but colour deficiency affects between 7 and 10 of every 100 males. It is rare in women.

Red-green colour deficiency (the most common kind) is a genetic abnormality. The eye detects colour through the use of cone-like receptors on the retina (the back of the eye). Cones exist for each primary colour of light - red, green, and blue (not to be confused with the primary colours in art, which are red, yellow, and blue). Colour deficiency results from a defect or deficit (but not absence) in the red and green colour receptors. Thus, affected persons can detect red and green, but not to the degree that normal people can.

Men and women share an identical genetic makeup save for two sex chromosomes. Women carry two X chromosomes (XX) whereas men carry one X and one Y (XY). The genes that code for red-green colour deficiency are carried on the X chromosome. They are referred to as X-linked recessive, because a person with an affected X and a normal X will have normal colour vision (the normal X being dominant to the affected X).

This explains why colour deficiency is so much more prevalent in males. If males inherit one affected X chromosome, then they have the disorder - since they have only one X chromosome to express. If women inherit one affected X chromosome, then they are carriers, and do not express the disorder. In order for a woman to express the disorder, they would need to inherit two affected X chromosomes - one from their mother, and one from their father - which is particularly rare (though this is a possible scenario were Evey and I to one day have children, her being a carrier).

Colour deficiency has dogged me throughout my life. On occasion, I have been particularly dejected because of it, thought it is by no means the worst genetic anomaly to inherit. As a result, while I have relatively intact colour vision and can see the world in colour, I have ceased noting colour the way a normal person notes colour. When a normal person observes someone on the street, they intuitively have noted the colours on that person. When they recall that person, they can recall the colours. They recall that stranger's hair was brown, their hat was red, and their jacket was green... I tend not to do this, because while I will usually be able to distinguish colours upon careful inspection, and while I can identify bright colours as easily as the next bloke, colour identification is often not so simple. Because I cannot instantly discern many colours, and because when I try I will sometimes be wrong, in many situations the colour of objects simply does not register in my brain - not that I am unable to see them.

When people discover my condition, they often spend the next period of time quizzing me. "What colour is this?" and "What colour is that?" This is because for them, it's fascinating. They cannot fathom what the world looks like from my perspective any more than I can fathom what it can be like to look at a colour and instantaneously intuit its composition. Today, I'm going to do my best to give you a taste of the world as I see it.

I learned my colours as a child, just like every other child. I learned them fine. But I learned them on very bright templates. The following two swatches demonstrate blue and purple as I learned them:

To you, it's probably quite plain that one of these is blue, and one of these is violet. To me, the major difference between these two colours is that one is light and one is dark. This is because my deficiency in red-green detection makes it difficult for me to identify that there is a little bit of red in the purple. It looks blue enough to me. The following two swatches, both of blue, look only marginally different from the blue and purple above:

Imagine my surprise as a child to put on my navy blue socks, proclaiming proudly, "These socks are purple" only to have my Mom correct, "Actually they're navy blue." I was dumbfounded. Baffled. What was navy blue? Was this some kind of alternate name for purple?

My parents had already discovered my colour deficiency when we were on vacation in the United States. I had looked up at a cloudy sky and declared, "They sky is pink." My Mom, who had taught me colours early because her brother is also colour deficient (it is in fact the same gene, which I inherited from my Mom, a carrier), said that upon hearing me make that statement, her heart sunk. Indeed, I had no concept of grey and pink. The swatches I had learned pink on looked indiscernibly similar to the cloudy sky in my childlike mind.

The two colours above look virtually identical to me, even laid side by side (which usually improves my colour discrimination). To me, they might as well look like this:

The above grey vs. grey gives you a taste of what I see in the pink vs. grey block. Just imagine yourself staring at those two grey blocks of colour knowing that they are different but at a loss to detect it. It's infuriating.

Blue-purple, grey-pink, red-brown, and light green-yellow are my most common errors in colour identification. But so far we have only talked about identifying discrete colours. Colour deficiency affects your life in ways much more profound than this.

Let us consider the colour above. It's identified as blue-violet. It's not quite blue, it's not quite violet. It's somewhere in between. What are the implications of making such an identification? First of all, it means you have a firm idea of what is blue and what is violet, and that they are very different things. The second is that you have identified that this is blue, but it has a little bit more violet in it than the usual blue. Or a little bit more blue in it than the usual violet. For me, such an analysis is not only not instantaneous, but entirely out of reach.

This put a dampener on my artistic aspirations. A lot of art involves shading. An artist who draws a red shirt will use a darker red to make the shadows and a lighter red to make the parts on which light is shining. In this way they generate contour. They might use ten different shades of red, and they can intuitively mix them - knowing exactly what matches with what. If I were to eyeball this, then I would likely shade parts of that red shirt brown by accident without noticing (and I have). Or I might colour Pikachu green instead of yellow (which I also have).

Let me provide an even more poignant example. Skin. What colour is skin? It's hard to quantify. Skin is a mixture of all sorts of colours. In grade 7 or 8, we learned how to paint and I attempted to mix a skin tone for myself. When I thought I was done, my friend kindly informed me that I had actually generated a particularly nauseating shade of green. At that point, I realized that I would never truly be able to take my art anywhere.

The left is a normal skin tone and on the right is a pastel green. While they do look different to me, the one of the right could just as easily pass off as a skin colour in my mind as the one on the left. Similarly:

The left is a normal skin tone and the right is a pastel pea green. Again, they both look like they would be normal skin tones to me. You can see that pastel colours are a particular problem for me. The brighter the colour, the easier it is for me to detect. Although skin is still an enigma.

You can begin to imagine what a damning effect this condition has on everyday life. Not only do I have trouble identifying colours but also difficulty intuiting their composition. Traffic lights look red, orange, and white. Green and yellow radars in video games make friend indistinguishable from foe. Gray stripes on a shirt are mistaken for red ones.

Let me conclude with a more recent example. Before I went to visit Evey in Kingston, I bought the game Puzzle Quest: Challenge of the Warlords of the Playstation store for my PSP. It had got some pretty rave reviews despite being a cheesy little puzzle game like Bejeweled. The goal is to line up crystals of the same colour in order to damage your opponent to death. The colours are blue, red, green, and yellow. Imagine my shock when I turned on the game and realized... I couldn't tell the green and the yellow crystals apart! After a few minutes of staring at the screen intently and giving myself an aneurysm, I realized that the crystals actually had little runic symbols on them - and that the symbols for the green crystal and the yellow crystal are different. It was a clever inclusion, though what would have been even more clever would be to have made the yellow and green colours more different. Or using yellow and white.

How do I get by in art then? Well there are two tricks I use, and neither of them are as good as colour vision. For skin, I usually look up a picture of a person online, and then I use the "magic wand" to steal their skin colour and use it in my pictures. I can adjust the brightness up and down to create lighter and darker shades. This works, but it is not the same as being able to intuit colours because usually when you shade lighter and darker, you are adjusting more than just the brightness, you have actually tweaked the amount of red-green-blue by a little (or a lot). For other colours, I depend on prelabelled and very useful swatches. This greatly limits the number of colours I can and do use in my artwork, but it is the best I can do. I'm also, as a result, more or less tied to PhotoShop, because Adobe seems to have been the only ones clever enough to label all their colours. It's essentially the digital equivalent to having labelled pencil crayons.

Still perplexed? Let's try one more exercise. The colour on the left is green. The colour on the right is purple. It's very minute though. Just keep looking at them, and you will realize that there is a little bit of green in the block to the left and a little bit of red in the block to the right.

So the swatches above are actually yellow and blue. But if you did the exercise properly and actually strained yourself trying to see what you were told was there, you've experienced a little bit of what it is to live my life, and that of almost 1 in 10 North American men.

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