Phosphenes: Your Own Personal Aurora Borealis
One night while sleeping, I rolled over, partially awake, but with my eyes closed. I noticed something strange: swirls and flashes of greenish light projecting across my eyelids.
What could be causing this strange display of lights in my eyes?
Naturally, my eyes shot open and I was no longer partially, but completely, awake. There were no lights in my room that might have instigated such a phenomenon. It was after three in the morning, and I live in the woods, away from traffic, buildings, or other external light sources. In fact, it was so dark that I’m pretty sure it was a New Moon.
I closed my eyes again, and there they were, again! Strange green ghosts flitting across the screen of my eyelids.
My own personal aurora borealis!
Since then, I’ve experienced lights that were yellow or pink or lavender, or the lights came as quick darting flashes or temporary dots instead of swirls or vapors.
Naturally, I blamed it on having multiple sclerosis. So easy to cast aspersions on the monster, after all.
MS is the pesky trouble-maker who messes with many of our sensory experiences, including our vision. We can have strange “shaking” eyeballs (nystagmus), extreme pain and blurriness from optic nerve damage or droopy eyelids …why not some strange, colored vapor when our eyes are closed?
Say hello to phosphenes
It turns out my “northern lights” have a name: phosphenes.
Phosphenes are a kind of visual experience in which unusual lights are generated in the eyes due to pressure against the actual eyeball or through stimulation of the visual field directly through a source other than light itself.
They occur when the cells in the retina fire in the absence of light, leading to impressions “seen” on the inside of the eyelids that are perceived as stars, bursts, defined shapes like circles, or swirls of light.
Usually, they are caused by sounds, sudden movement, or pressure on the eye, all of which can aggravate or inflame the optic nerve. Strong magnetic fields might also elicit a phosphene response.
If you’ve ever closed your eyes and rubbed really hard, you may experience an eye-shaped phosphene projected onto your eyelid afterward that lasts for a second or more before disappearing.
Phosphenes and multiple sclerosis
Phosphenes are considered a normal phenomenon, but they have also made a brief acquaintance with MS.
The most obvious relationship phosphenes have with MS is by way of the common symptom, optic neuritis.
In optic neuritis, misfiring nerves in the brain by way of the optic nerve can render these strange little light shows.
Interestingly, they don’t happen only at night, but at any time when dysfunctional optic nerve behavior occurs. You’re just more likely to notice at night.
About a third of those with MS who experience optic neuritis also experience phosphenes.
Phosphenes in those with MS may be sparked by sudden noises or movement of the gelatinous coating in the eyes, as well.
So-called “movement phosphenes” are known to follow any side-to-side movement of the eye. The imagery will fade eventually, but may still repeat itself after a brief period of rest.
Phosphenes are thought to be related to another MS-related symptom: L’Hermitte’s sign, in which a buzzing electrical sensation takes place briefly in the spine when the head is tilted forward. In either case, these strange sensations are considered characteristic only to those who have MS.
It’s important to note that phosphenes are not necessarily a sign of relapse or disease progression. They can be caused by other conditions or may just be a random and harmless occurrence with no known cause.
In my case, they have no relationship to MS, as far as my doctors and I can tell. My optic nerves are healthy, and I don’t have any of the other conditions that might bring on a sudden and unexpected display of dancing lights.
So don’t panic if you suddenly find yourself witnessing an aurora with your eyes closed; unless you have other active symptoms suggesting an exacerbation, chances are good it’s just a pretty light show and nothing worse.
The way I see it (pun intended), I may still have witness the aurora borealis to check off my bucket list, but at least I can also claim to “make my own Northern lights!”