I’ve only been knocked out once in my life. I was maybe 19 or 20 and was playing tackle football with some friends. I'm no athlete but I'm really hard to knock over so, with three guys hanging off of me already, a fourth gets his arm around my neck and brings me down. I remember falling, but I don't remember the impact.
The next thing I do remember is looking up at the sky with my friends standing over me in a circle. Nothing hurt, I didn't feel dizzy, and I felt fine the rest of the weekend. But something weird happened with my vision for the first time.
Imagine, for a moment, that you start seeing a bright spot in your vision—like what you’d see if you stared too long at an intense light source. But it doesn't fade over time; rather, it persists and grows, tracing an arc around your field of view. And then you realize that it’s not just a bright spot, but you can't even see anything behind it. It looks the same whether you have either one or both eyes open. You wave your hands in front of you and it’s as if they disappear as they pass behind a sparkly obstruction floating in the air. Then after about twenty minutes it just kinda fades away.
The first time I experienced this vision impairment was the very day I was knocked out. Later in the day I was talking to somebody when it started and, as it progressed, I became a little alarmed. I tried to make sense of what I was...partially...seeing, but I was able to piece together all the details in the short time it lasted. Of course as a stupid college kid I didn't think about it after it went away, and I never visited a doctor for a consultation. I connected the experience to my injury, but otherwise had no clue what was going on.
You know those wacky, spider-like head massager thingies? They look kinda like those Maman sculptures by Louise Bourgeois but with thin copper wires that spread open as you push the massager over somebody's (or your own) head.
I was at the mall in my mid-20s with my wife and some friends, and as we passed by a kiosk one of the friends stopped and grabbed a massager dingus.
"You ever see one of these things? They're scalp massagers, and they make your head tingle."
And without missing a beat she plopped it down over that back of my skull. I kind of shivered and felt goosebumps from head to toe, like my whole body convulsed at once. On the way back to the car, I noticed that strange visual anomaly creeping in, and I was glad my wife was driving instead of me.
Six? Maybe seven times all together in the past 17-18 years. This visual weirdness doesn't happen too often. The frequency hasn't increased, the severity hasn't increased, and I’ve never experienced any pain, nausea, or other discomfort/impairment when it happens. The most recent occurrence was just last week at the coffee shop. On the drive over, some intense reflections of the sun off of some windows caught me in the eyes. As I was sitting down to enjoy my espresso, what I thought were merely persistent bright spots spread out into my old surreal, annoying friend.
I'm not one to self-diagnose, but since I’ve historically been lazy about visiting physicians, I have done some research about this condition. It’s called a scintillating scotoma, or migraine aura. It happens when electrical impulses start to spread over the surface of the visual cortex of the brain, which is at the back of the skull. Most folks experience this condition preceding a migraine headache, and while there may be pain, dizziness, nausea, or speech trouble before the headache takes over, it’s possible for people to simply experience the vision problem. Some folks, like me, never get a headache afterward. I'm given to understand that common optical migraine triggers can also trigger the scotoma.
I’ve never had a migraine headache in my life (to date...knock on wood), but I’ve had these visual migraine precursors. I'm fairly certain that head injury in college is the root cause since I landed on the back of my head. The scalp massager seems like a clear trigger based on the overstimulating input at the back of my skull. And the most recent incident involved a common migraine trigger: intense light.
These days I do have a primary care physician. Migraine aura doesn't worry me all that much, but since this all seems to stem from a head injury back in the day, I might as well tell my doctor about it at my next visit.