Phosphenes refer to the “stars” we sometimes see when we accidentally bump our heads… or, the weird light we see when we rub our eyes – even in a pitch dark room. In both cases, our brain is being tricked into seeing light that’s NOT really there… and the fake light images are known as phosphenes.
So, where do they come from? Well, normally when we look at something, the light-sensing cells in our retinas translate what we see into electrical signals… and our brain interprets those signals to figure out what we’re seeing, whether it’s a bunch of flowers or a pizza!
But you can also trigger those electrical signals by physically manipulating ANY part of your visual system. So, if you rub your eyes, the pressure from your fingers activates your retinal cells in a way that makes you think you’re seeing light… and if you suffer a concussion, the actual movement of your brain within your skull can trigger an electrical current similar to seeing stars!
And get this: There are also many cases of blind people claiming to “see” colors when they listen to music. What they’re actually seeing are phosphenes generated by sound waves stimulating their visual system.
The good news? Most phosphenes are completely harmless. But talk to your doctor if you’re seeing weird lights on a regular basis, WITHOUT any outside stimulation. Because that could signal a serious injury.