Optic Nerve Plays a Major Role in Migraine Pain
At Axon Optics, we conduct clinical studies and keep an eye on studies regarding light and migraine. The results of this particular study are rather striking when you see it for the first time – light can trigger migraine pain even in blind subjects. Part of the study took place in our hometown of Salt Lake City. The study’s co-author, Dr. Kathleen Digre, is a researcher at the University of Utah. For many people, light plays a significant role in either triggering or exacerbating migraines. Because we use our eyes to see, it’s easy to think of migraines being triggered by the visual or image-making effects of light. But the study by researchers at Harvard Medical School and the University of Utah found light causes migraines even in non-seeing subjects, indicating a much more complex nerve response that doesn’t depend on the image-making aspect of vision and sight.
Light Triggers Migraine in Blind Subjects
For anyone who’s ever had a migraine, the idea that light can cause migraines to occur or become worse is nothing new; but the concept of light as a nerve stimulator independent of sight and vision is still being explored. In the current study, the researchers evaluated the effects of light in 15 blind women and 5 blind men who suffer migraines. Aside from blindness, the people in the study had similar demographics to migraine sufferers who were not blind.
Six of the subjects who had no light perception at all due to optic nerve damage or removal were unaffected by light during their migraine episodes, suggesting the retina plays a role even when the eyes don’t “see.” The remaining 14 subjects were able to detect bright lights directed at their faces, and had significant reactions when light was shone on them during migraine attacks. Using a subjective scale from 0 to 10, these subjects rated migraines at an average of 9.2 in a lighted environment compared to 6.2 in a dark environment. The researchers say their results underscore the presence and role of pathways triggered by the optic nerve that are not related to image formation, and also indicate people who suffer from migraines may be more sensitive to these effects. Overall, the study underscores the importance of wearing protective eyewear to cut down on light brightness and glare as an important tool in helping to avoid migraines and in modulating or reducing symptoms when headaches do occur.
Blocking Painful Light
Does that mean migraine sufferers need to wear dark lenses at all times to prevent migraines from occurring? No – not all types of light cause painful symptoms, and the key to avoiding migraines or reducing symptoms when they do occur is to wear lenses that block the types of light that trigger pain. Axon Optics’ therapeutic eyewear was designed specifically for that purpose; in fact, a study conducted by researchers in England found the lenses reduced the number of migraines from six to two per month in the subjects they tested. If you suffer from migraines, find out about Axon Optics’ migraine glasses and how they could help you reduce your headaches and your symptoms.
Article Source: Noseda R, Kainz V, Jakubowski M, et al. A neural mechanism for exacerbation of headache by light. Nature neuroscience. 2010;13(2):239-245. doi:10.1038/nn.2475. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2818758/
