If you've ever had a migraine, you've probably experienced photophobia, the painful sensitivity to light that sends you scurrying, eyes closed, to the darkest dungeon you can find. In that moment, you're probably wishing for a way to (temporarily) unplug your eyeballs and put an end to the agony. Researchers at The Salk Institute could have a potential answer: A compound that switches off light sensitivity without affecting vision.
Scientists have known for a century that the ability to sense light is separate from vision. Blind humans still tend to wake in daylight and sleep at night, and newborn mice scurry away from bright light before their eyes are developed enough to see. This light-sensing mechanism uses melanopsin receptors in the eye, which also control how the pupil reacts to different light levels. Research biologist Dr. Satchin Panda and his team discovered that chemicals called opsinamides could knock out melanopsin's activity, removing the pupil's reaction to bright light, without disturbing vision in mice.
While clinical use is still far off, these light sensitivity blocking compounds could be a boon for migraine sufferers dealing with light sensitivity, as well as night shift workers who have difficulty sleeping when the sun's out. Then again, since we're all messing up our sleep cycles by staring at glowing screens all night and day, maybe this stuff will have a much broader impact. [MedicalXpress]