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Colors Help Set Body's Internal Clock

Posted by samzenpus on from the sleepy-blue dept.

First time accepted submitter MakeItGlow writes A new study by researchers from the University of Manchester found that mice use the color of light to set their body clock. The researchers investigated whether color signals from the eyes wound up in the suprachiasmatic nucleus—the part of the brain in vertebrates that keeps time using electrical and chemical signals. From the article: "Scientists have long known about the role light plays in governing circadian rhythms, which synchronize life’s ebb and flow with the 24-hour day. But they weren’t sure how different properties of light, such as color and brightness, contributed to winding up that clock. 'As a sort of common sense notion people have assumed that the clock somehow measures the amount of light in the outside world,' says Tim Brown, a neuroscientist at the University of Manchester in the United Kingdom and an author of the new study. 'Our idea was that it might be doing something more sophisticated than that.'”

1 of 52 comments (clear)

  1. Been there, done that. by Okian+Warrior · · Score: 5, Interesting

    I'll just leave this here:

    http://science.slashdot.org/co...

    Noontime clear-sky sun measures 9500, blue light through office window with indirect daylight is 250, a desk lamp measures 45, and an LCD TV up close measures 7 uW/cm^2 in the frequency range of the retinal ganglia (480 nm) which is thought to be the part of the eye that senses daily cycles. (Mammalian Eye [wikipedia.org] on Wikipedia.)

    So far as I can tell laptops and related devices don't generate an appreciable amount of energy in this range, it's more the artificial indoor lighting.

    As an experiment, I've started wearing red-tinted wrap-around sun glasses 2 hours before bedtime. I can still work, read, watch TV and all that, but the glasses mask off the blue frequencies, telling the brain that the sun has gone down.

    It had an almost immediate effect. I'm a long-time sufferer of insomnia who has tried everything, but wearing the glasses fixed the problem in the first week.

    I'm also a lot more "peppy" during the day, and I wonder if long term exposure to late-night artificial lighting (and low level during the day) is a cause of depression. Depression meds take about 6 weeks to have an effect, so I'm guessing that it would take about 6 weeks for the glasses to have an anti-depressive effect as well. I'm on week 3 with the glasses.