I am boran2, tonight's KosAbility diarist. Upon first seeing this series, I considered posting about my ulcerative colitis, currently in remission. Instead, I thought it might be interesting to post about my color blindness.
KosAbility is a community diary series posted at 5 PM ET every Sunday and 5 PM every Wednesday by volunteer diarists. This is a gathering place for people who are living with disabilities, who love someone with a disability, or who want to know more about the issues surrounding this topic. There are two parts to each diary. First, a volunteer diarist will offer their specific knowledge and insight about a topic they know intimately. Then, readers are invited to comment on what they've read and or ask general questions about disabilities, share something they've learned, tell bad jokes, post photos, or rage about the unfairness of their situation. Our only rule is to be kind; trolls will be spayed or neutered.
This story began for me in the 4th or 5th grade, I can't remember exactly which one. Some unknown purpose required that the entire student body of my suburban Long Island school be marched through the nurse's office, in one door and out the other. The line of students stretched for a seemingly endless distance. When I got within the entry door I saw that the students were looking at something on the nurse's desk and then moving along. When it was my turn I was asked to identify the numbers contained within a circle of colored spots. The trouble was that I couldn't see any numbers. In the less than enlightened practices of the time, I was pulled out of line and made to stand off to the side until the entire student body was finished. I was never told why. As best as I can recall, I was simply dismissed back to my class afterwards, apparently the only student of several hundred to have been pulled from the line.
It was only later on that I learned exactly what had happened that day. I was unable to see what was within the circle of spots because of color blindness. Exactly Why this condition was not identified previously by my parents will forever remain a question unanswered. Perhaps they were to busy abusing caring for us 5 kids.
Color blindness comes in several different varieties. There are those rare individuals that are unable to see any colors at all. For most people, it is more a matter of being color impaired. That is, some portion of the color spectrum can't be accurately seen. A full discussion of color blindness would require technical knowledge far beyond my own. For those seeking such an inquiry, Wikipedia has that and more.
Here is a good simple statement regarding color blindness:
People with normal colour vision are "trichromats". That is, the receptors in the retina of the eyes process light as a blend of all three primary colours. Colour-blind people are dichromats, and can only process colours using a blend of two out of the three primary colours. Which two primary colours used dictates the type of colour vision defect that person has, and there are several different types the commonest being the red/green type, and the one most people have heard of.
An example of the circle-of-spots test, the Ishihara test (from Wikipedia commons) is seen directly below. I can't see any figures within the circle. The number "74" is seen by those with normal perception.
The everyday impact of this condition is actually hard to convey because I'm never quite sure of things. What I do know is that beyond the bright primary colors of toddler toys things can become difficult. Most prominent amongst my difficulties is the frequent inability to differentiate greens and browns. (Not helpful when pruning dead branches from my bonsai juniper.) While the bright greens of toys are usually no problem, other shades can be impossible to determine. Recently, we made a weekend trip to Cape May, New Jersey, home of some 600 Victorian structures. Many of these are brightly painted, some less so. madam boran expressed her admiration for one example that I thought to be painted a nice shade of brown. To my surprise, it was actually sea foam green, a color that I am apparently unable to appreciate. Blues and purples can present a similar difficulty. In fact many subtle shades also present a problem. I am often left asking companions to identify colors.
Green traffic lights look almost white to me. Fortunately, amber and red lights are no problem. Don't ask me to pick out ripe/near-ripe bananas. madame boran recently experienced disappointment after asking me to do so. Then there are those color-coded charts and graphs, the darling of political junkies everywhere. Often featured on the dkos front page, they are often perhaps only partly useful to me.
Clothing is a particular problem. I have simplified things by wearing mostly blacks and grays and a few blues. (There is that one daring brown outfit.) Even my socks are all black. Clothes shopping is always interesting, especially if I have to find someone to confirm my color choices. Sales clerks only have so much patience for my color-related questions.
It has been suggested that color blindness is actually an evolutionary advantage. Color blind individuals are less subject to the effects of camouflage, an advantage for hunters and warriors. Furthermore, color blind individuals are somewhat better able to see at night, having greater sensitivity to luminescence. While these are interesting, I'd be far happier with something approaching full color perception.