color vision deficiency

[meridannight]

i discovered today that in addition to color blindness, some people are color-deficient. they have trichromatic vision (meaning they can distinguish red, green, and blue like in normal color vision) but they can have one cone cell (cone cells are responsible for our ability to detect colors) shifted in spectral sensitivity (they can, for example, have a 'weak green' or a 'weak red' vision).

physiologically, it means the pigment protein in the cone cell is different from what individuals with normal color vision have, and this different protein will have a different sensitivity to the wavelength of light (i.e. color). it's called anomalous trichromacy. so, while they are not impaired in a sense that color blind individuals are, they do see a slightly different world than people with normal color vision (reds can appear darkened, for example).

i found that interesting, i didn't even know it existed.

the Farnsworth-Munsell 100 is one of the more detailed tests to measure color vision deficiency. i know online versions aren't very reliable, but it's fun to do it. i got a score of 16, with minor errors in the G, BG, and YR areas (adding up to 'no defect' in color vision).

if anybody wants to try it:

Farnsworth-Munsell 100 online version

[MikeW]

I see color slightly differently between one eye and the other… I've never had it checked so I don't really understand "why" it is… I just know that if I close one eye and then the other in rapid succession, the colors vibrance between one eye and the other is slightly different. It could just as well be psychological (right brain / left brain) as physiological, I suppose. As a painter I often used it to help me evaluate color tones I was matching.

[Bowyn Aerrow]

I have slight color blindness - It hasn't been an issue to me, but has lead to some misunderstandings and lowers my ability to be 100% homosexual since I cannot coordinate colors to save my arse. So alas, no sense of fashion, no sense of decor.

[erectrician4u]

said im color blind dont know if i agree or not been an electrician for 40 years never had any problems with colors

[meridannight]

said im color blind dont know if i agree or not been an electrician for 40 years never had any problems with colors

lol. as i said, these internet tests are not 100% accurate. it could be that the spectrum of your monitor is off, or it could be that you have some slight deficiency in color perception. enough to deviate from normal, but not enough to make you incapable of functioning normally under most circumstances.

if you couldn't distinguish between red and green, or between yellow and pink (in case of the lack of a blue cone), you would know it already from your work as an electrician.

you could investigate it further to see if there's anything there, or if it was just an anomalous result.

[MENTION=20947]MikeW[/MENTION], that's interesting. thanks for sharing. for your information, if it's only affecting one eye it can't be a brain problem. it's most definitely in the eye then. problem in the brain affecting vision, would affect vision in both eyes the same way (it's to do with the way the neural pathways from the retina to the visual cortex are arranged).

[Beaux]

My husband is color blind, which is what led him to join the Marines rather than joining the Airforce which was what he wanted to do originally. Most of the time I don't even think about it, but there are times when it can be frustrating. I pick all of his cloths, and he doesn't argue about that, but we had an argument a couple of months ago about a new rug. I liked it and he didn't. It took a couple of days before I realized that he couldn't see the variations in the rug's pattern because the blues and greens are not visible to him...

I recently read an article about a new kind of glasses that will be coming out in the next year or so that correct color blindness, and am looking forward to seeing my husband in a pair! Apparently, the inventor wasn't trying to cure color blindness, he was just making a new kind of safty glasses until a friend who was color blind tried out the glasses and freaked out over seeing colors he had never seen before! The only thing that worries me, is what if my husband gets a pair and then we realize that our personal tastes don't match-up after all!!! LOL :-o
~Beaux

[Cridders88]

I recently read an article about a new kind of glasses that will be coming out in the next year or so that correct color blindness, and am looking forward to seeing my husband in a pair! Apparently, the inventor wasn't trying to cure color blindness, he was just making a new kind of safty glasses until a friend who was color blind tried out the glasses and freaked out over seeing colors he had never seen before! The only thing that worries me, is what if my husband gets a pair and then we realize that our personal tastes don't match-up after all!!! LOL :-o
~Beaux

Really? Being red-green colour blind myself I would love to try a pair!

[meridannight]

I recently read an article about a new kind of glasses that will be coming out in the next year or so that correct color blindness, and am looking forward to seeing my husband in a pair! Apparently, the inventor wasn't trying to cure color blindness, he was just making a new kind of safty glasses until a friend who was color blind tried out the glasses and freaked out over seeing colors he had never seen before! The only thing that worries me, is what if my husband gets a pair and then we realize that our personal tastes don't match-up after all!!! LOL :-o

Beaux,
they don't correct color blindness (it is not possible to correct it because the problem is in the retina, and the genes; in order to correct it you have to correct the eye itself). what these glasses do, is they assist the vision, they make certain hues stand out a little more.

see this:

iso glasses

anybody who makes a claim that their product (glasses) correct or cure color blindness is scamming people. what that person in the example quoted may have seen was an enhanced spectrum, just like you would see a different color balance when putting on purple glasses.

a person who is color blind has one of the three cones that are responsible for color detection missing. mostly it is either the red or the green cone that is missing. in very rare cases it is the blue cone.

you cannot correct or cure such a defect in vision with glasses/lenses (they have tried to do it since 1981, at least). because the retina is still incapable of seeing whatever color they are deficient in. they still don't have that cone. you can throw all the e.g. red at them, and there's still no red there. in order to see red you need the pigment in that red cone. if you don't have the red cone, no pigment, no red. (if you are interested i can explain the physiology behind it in more detail to you, it's fascinating).

in sum, the glasses out there designed to assist color blind individuals won't give them the color vision you have. they alter it, yes, but to say they correct it is completely false.

There is generally no treatment to cure color deficiencies. ″The American Optometric Association reports a contact lens on one eye can increase the ability to differentiate between colors, though nothing can make you truly see the deficient color.″

Optometrists can supply colored spectacle lenses or a single red-tint contact lens to wear on the non-dominant eye, but although this may improve discrimination of some colors, it can make other colors more difficult to distinguish.

In September 2009, the journal Nature reported that researchers at the University of Washington and University of Florida were able to give trichromatic vision to squirrel monkeys, which normally have only dichromatic vision, using gene therapy

Recent advances in technology have lead to new types of lenses being developed that allow around 80% of people diagnosed with colour blindness to see a better spectrum of colours, especially those with classic "red/green" colour blindness. They work by blocking certain wavelengths of visible light in order to heighten the differences between colours.[47][48]

[himself]

I got 16. I think it was an accurate test. I didn't have to think about it. I just shifted the blocks if they looked wrong, which I assume is the way to do it. Usually with online tests, it's really hard to give accurate answers to the questions.

[Bookworm]

I'm red/green colour blind so I thought I'd give this a bash - my result was an error score of 212 (border line severe) :eek:

I really had to concentrate but I didn't think I'd done this badly :biggrin: