Unlike white, blue, and red, green light does not make migraine headaches worse, but soothes them. This is the conclusion reached by American scientists, the authors of an article in the journal Brain, and briefly about the discovery is reported by New Scientist.
During migraines, people also suffer from increased sensitivity to light. Due to photophobia, patients are forced to wear sunglasses and hide in dark rooms. Scientists explain this by the pathological mixing of two types of neurons in the thalamus: those that transmit visual information from the retina, and those that are responsible for pain. As a result, in migraine headaches, light increases pain, which in turn causes visual problems.
Rami Burstein of Harvard and his colleagues conducted an experiment with volunteers suffering from migraines. They were placed in a dark room and gradually increased the intensity of white, blue, green, yellow and red light. Scientists recorded the reactions of patients, and also measured the activity of neurons that send signals from the eyes to the brain (using an electrode attached to the eyelid), and the activity of the brain in general.
It was found that blue, white and yellow increase pain in the same way. However, green light (low intensity) eased the pain. Scientists have no idea why radiation on this particular wavelength was an exception to the rule. Green light induces less electrical activity in the eyes and brain than other colored rays.
Scientists obtained a similar result by connecting electrodes to the brain of experimental rats.
Burstein hopes his discovery will lead to the development of sunglasses for migraine sufferers that filter all light except green.