Posted tagged ‘Meares-Irlen Syndrome’

Colour tolerance and myopia

May 11, 2010

I’ve mentioned before that my partner really hates coloured light.  I haven’t tried that many colours on him, just the blue lightbox and a range of yellow and amber bulbs, but he has strongly disliked all of them.  My eye specialist has finally given a reason for why this might be the case. Colour, she says, is very important to myopes (short-sighted folks), and the more myopic you are, the more colour will matter to you.  I’m fairly fussy about colour myself, I can’t stand fluorescent light (though that’s probably a case of colour and flicker) and I’m very picky about colours when it comes to reading and tinted lenses, though I don’t know how far that is caused by having Meares-Irlen Syndrome.  I’d be curious to test my partner some time and see how much colour he can tolerate, if there are any colours he finds easier than others, or if he’s only really happy when the light is white or close to it.  I mentioned to the eye specialist that I find yellow and orange light mercifully comfortable, and she said, “Oh yes, yellow light is very soothing for the eyes.”  For reference, here is how myopia is usually categorised:

0 to -3: mild myopia
-3 to -6: moderate myopia
-6 to -10: severe myopia
over -10: extreme myopia (not usually listed as it’s so rare)

Including astigmatism, I’m about -7, so my eyesight’s worse than that of most people but I still know a fair few people who are at a similar level to me.  My partner, on the other hand, is about -19.  Before I met him, the worst myopia I’d encountered was one guy at -12 and a woman at -10.  Several opticians he’s been to have never seen myopia as bad as his, although it’s by no means the worst around.

So his reaction is unlikely to be the norm, and even my degree of fussiness about light colour seems fairly unusual.  To people who have tried different coloured light or lenses, are you myopic, and have you found difficulty in tolerating the colour?

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Are there any risks to light or darkness therapies?

January 26, 2010

There are risks to everything in life, but the risks for light and darkness therapies are minimal.  For starters, neither therapy interferes with medication, so that you may combine bright light therapy with antidepressants or darkness therapy with sleep aids if you need to.  Here are all the risks that I am aware of.

If you have macular degeneration, the current consensus seems to be that blue light may be damaging, though this appears to be largely theoretical.  This covers all bright lightboxes, as the ones which produce white light still contain blue light within the white, and in fact may contain even more light at the damaging wavelengths, which are actually below blue light.  You should probably avoid bright light therapy if you have macular degeneration, and will want to think about it carefully if you are at high risk of macular degeneration.  More information here, where the possibility of using green light instead is also discussed, and here.

Some lightbox manufacturers claim that their rivals’ products will cause untold damage in all sorts of ways.  Read the above link, which explains what’s really going on.  Short version: ignore them unless you already have, or are at high risk of, maculuar degeneration, in which case look into dawn simulation and/or darkness therapy instead of bright light therapy.  I find it extremely off-putting when manufacturers spread bad science in an attempt to knock the competition, but up to a certain level I think we just have to put up with it here, as they’re all doing it.

Bright light therapy may cause mania in bipolar disorder.  Read more about this here.  Changing the time of the light therapy may help, or just going for darkness therapy instead.

Traditional bright light boxes use very bright fluorescent light, and a number of people react poorly to fluorescent light (migraines, visual disturbances, nausea etc.)  Conditions which make this reaction more likely include migraine, ME/CFIDS,  MS, epilepsy, Meares-Irlen Syndrome, dyslexia.  Stay away from fluorescent lightboxes if you already know that you react badly to fluorescent light, and in general it’s a good idea to try before you buy with lightboxes anyway.

The other type of bright lightbox uses LEDs, either white or blue.  Some people don’t get on well with these either, although I think it’s a much smaller group.  Again, try before you buy, especially if you know that you’re sensitive to light. As the LEDs are displayed in a grid of little dots of light, some people report that they experience “spotting” in their vision.  It’s generally thought that these people were using the lightbox incorrectly, however.  It should be off to one side or above your field of vision, and you should not be staring directly at it.  This is how all bright lightboxes should be positioned, including fluorescent models.

For any problem relating to light sensitivity, you may be able to get past it by gradually increasing the brightness and length of time you spend in front of the lightbox, or using the lightbox for longer at a dimmer setting.  Take note of which lightboxes allow you to adjust the brightness if you think this will apply to you.  If you can’t handle bright light, consider dawn simulation and/or darkness therapy instead.

If you have ME/CFIDS or another condition which is highly debilitating, I now recommend making these changes gradually, just in case the shift in your sleep hormones sets anything off.  Start the darkness therapy one hour or even thirty minutes before bedtime, then gradually increase it.  Use a lightbox for short periods only to begin with, and on a dimmer setting if one is available and you are concerned about this.  I doubt that dawn simulation would cause any problems, but I’d suggest only introducing one change at a time.

A few people just don’t get on with coloured light in general or certain colours of light, including my partner, who reports reactions similar to the way I react to fluorescent lighting (including nausea).  This is more likely to occur if you have Meares-Irlen Syndrome and/or dyslexia.  Personally, although I have MIS I’m fine with blue and orange light.  It’s a highly individualised condition.  If this is the case for you, and it’s easily tested by buying a conventional coloured lightbulb that’s the same colour that you will be using, then go for a white lightbox instead of a blue one if you want bright light therapy.  Dawn simulation won’t be affected.  It may not be possible to practice darkness therapy fully, but at the very least you can dim the lights in the evening and avoid TV and computer screens.  Using brown-tinted glasses instead of orange glasses may work, as they don’t distort colours in the same way, although they’ll need to be fairly dark (brown is orange + black) to block blue light entirely.  There isn’t an option for coloured lightbulbs, but again, a brown screen filter for computers/TVs may be acceptable.

A disadvantage rather than a risk: if you do any sorts of art or crafts work, remember that colours will appear fairly different with a blue lightbox on and completely changed under yellow/orange lighting/glasses.  I try to plan my quilting so that I don’t need to judge colours for anything I do in the evenings, and have found that restricting my activities at that time helps me to wind down for sleep anyway.  Both fluorescent and LED white lightboxes give off rather a cold white light, which may make a difference if you usually use incandescent bulbs. I use a mixture of incandescent (yellowy white) and halogen incandescent (still a warm white but brighter than incandescent) bulbs on my sewing desk along with a white LED lightbox, and while I can see that the lights are a slightly different colour, it’s not causing problems in my work.

A friend of mine who suffers from depression and poor sleep reports that his mood drops significantly if he is in a dimly-lighted room, so if this is the case for you, darkness therapy is probably not an option.  On the other hand, this may be a short-term effect only.