Drug-free migraine therapy Green light for the headache

Migraine is not only characterized by severe headaches, but many sufferers also suffer from extreme photosensitivity. However, scientists at Harvard Medical School have now found that a certain range of green light is unaffected and that this light can even reduce migraine headaches.

About 15 percent of the world's population, according to the researchers suffer from migraine headaches, which are often amplified by light and associated with extreme photosensitivity. Many sufferers therefore retire to a darkened room until the acute attack is over. However, the research team led by Rami Burstein of Harvard Medical School in his recent research showed that exposure to a narrow spectrum of green light reduces photosensitivity and headache. The researchers published their results in the specialist magazine "Brain".

A narrow spectrum of green light can relieve headaches in migraine sufferers. (Image: dundanim / fotolia.com)

Connection between photosensitivity and migraine
More than 80 percent of migraine attacks are related to photosensitivity and are exacerbated by these, explain the researchers. "Many migraine sufferers therefore seek the comfort of darkness and isolate themselves from work, family and everyday life," says study leader Burstein. Although the photosensitivity is usually less stressful than the headache itself, the inability to tolerate light could additionally severely restrict those affected.

Even blind migraine patients respond to blue light
The researchers came across the surprising discovery five years ago that blue light causes a reaction even in blind migraine patients. So they came to the idea that the abnormal photosensitivity in migraine patients could be alleviated by blocking the blue light. They did further research on patients who could not see all the colors of the light and "developed a way to study the effects of different colors of light on headaches in patients with no visual impairment," reports Havard Medical School in a press release of the study findings.

Red light pain reduced by 20 percent
As part of their current study, Burstein and colleagues have now found that the condition of migraine sufferers worsened in all colors of the light spectrum, except for a narrow spectrum of green light. At high intensity of light, such as in a well-lit office, nearly 80 percent of patients complained of headache intensification - in all colors except green, according to Harvard Medical School. In low intensities, the special range of green light has even relieved headaches. The pain had decreased by about 20 percent.

Different signal strength in the brain
In order to understand the effect of green light in migraine patients, the researchers used special experiments to measure the strength of the electrical signals generated by the retina (in the eye) in the different colors and the response of the cerebral cortex (in the brain) to each Color of the light determined. They found that blue and red lights produced the largest amount of signals - both in the retina and in the cerebral cortex. On the other hand, the green light has triggered the smallest signals. There were also differences in signal transmission in the thalamus. The neurons in the area of ​​the brain, which carries the information about the light from the eye to the cortex, responded the fastest to blue light and the slowest to green light, the researchers report. This could explain why migraine patients react positively to green light.

Hope for therapeutic applications
The new findings "offer real hope for patients with migraine and a promising path for the future," emphasizes study leader Rami Burstein. So scientists are already working to develop a cheap light bulb that emits "pure" (narrow band wavelength) green light at low intensity. So far, the cost of a corresponding light bulb according to the researchers, however, still unaffordable high. Even cost-effective sunglasses that block the entire spectrum of light except the narrow range of pure green light, are already in planning. But the technology to block everything with sunglasses except for pure green light is only in light microscopy, which is also very expensive. In the long term, the use of the green light, according to the scientists, however, could represent a very attractive treatment method for migraine. (Fp)