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March 2010
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How Light Boosts Migraine Pain

Light can make migraine pain worse. A new study of blind patients may help explain why. The finding could eventually lead to better treatments.

More than 1 in 10 people nationwide get recurring migraines—often described as a pulsing or throbbing in one area of the head. To discover how light can worsen the pain, NIH-funded scientists studied 20 blind patients who suffer from migraines.

Six of the volunteers couldn’t detect any light, either because their eyes were removed due to disease or because of damage to the optic nerves, which connect the eyes to the brain. The other 14 patients could detect some light but couldn’t perceive images.

When the 14 patients were exposed to light, their migraine pain got worse. In contrast, light had no effect on the 6 volunteers who were totally blind. The scientists concluded that the optic nerve must play a key role in light-induced migraine.

The researchers then searched for the cells in the eye that might trigger the pain. They knew that the eye’s main light-detecting and image-producing cells were not responsible, because these cells were damaged in the 14 blind patients. Instead, the researchers focused on rare light-sensing cells that help maintain the sleep-wake cycle and help the eye’s pupil enlarge or shrink in response to light.

Animal studies showed that these rare cells carry light signals through the optic nerve and on to brain cells that transmit pain. The research suggests that non-image-forming eye cells may help trigger migraines.

“Clinically, this research sets the stage for identifying ways to block the pathway so that migraine patients can endure light without pain,” says lead researcher Dr. Rami Burstein of Harvard Medical School.

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  Health on the Go

Wondering what the side effects are for your new prescription? Or the symptoms of H1N1 flu when the school nurse calls to say your child doesn’t feel well? A new NIH web site called Mobile MedlinePlus can help.

Mobile MedlinePlus lets you gain ready access to reliable health information that’s optimized for your mobile phone. It’s available in English at and Spanish at

Some experts predict that within the next 5 years, more people will connect to the Internet using mobile devices than with desktop or laptop computers. NIH’s National Library of Medicine created Mobile MedlinePlus based on the popular MedlinePlus web site. The MedlinePlus web site provides authoritative consumer health information to over 10 million visitors per month.

The mobile version of MedlinePlus includes summaries for over 800 diseases, wellness topics, the latest health news, an illustrated medical encyclopedia and information on prescription and over-the-counter medications.

You can use the site to get tips on healthy food choices when grocery shopping, or select an over-the-counter cold medicine at the drug store. Or you can learn about safe drinking water when you’re traveling abroad.

If you access the Internet with mobile devices, bookmark Mobile MedlinePlus. It puts reliable health information at your fingertips.



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We Can!

Want to help your family avoid excess pounds? Check out the newly redesigned web site for We Can!, a national education program designed to give parents and communities ways to help kids stay at a healthy weight. Get tips on choosing low-calorie snacks, getting active and cooking fun, healthy meals.

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