I hope I can describe this adequately. With my eyes closed, I can apply gentle pressure to my eyes with my fingertips and generate patterns that I can see clearly. At the lightest pressure, the pattern appears to be the blood vessels in my eyes. As the pressure increases, the patterns change to varying geometric arrangements, mostly looking like black and white (or more accurately, red and white) “twisted” or “bent” checkerboards.
A number of years ago, I came across a study of this phenomenon in a magazine or science journal of some sort, but never actually had the time to read the article. Now, I’m curious; what causes these patterns? The blood vessel patterns I can pretty much understand, but what about the geometrics?
Just so you don’t feel alone, I can do the exact same thing. I could make the patterns vary and speed up/slow down with my thoughts, but it was always the same ‘going through a tunnel’ motif.
IIRC, the paterns and “light” flashes are generated by your brain’s attempt to interperate the signals your eyes are sending. When you push on your eyes, your rods and cones still react and send signals to your brain. I’m sure another doper will prove me wrong or provide a link or something.
The light displays are called phosphenes. Here’s a few threads on them:
What do I see?
Odd geometric patterns when I close my eyes
How do phosphenes (light shows behind the eyelids) happen?
Beautiful. Insightful. And perfectly the answer I was looking for. Thanks, all!
Isaac Newton was so fascinated by these that he took a blunt pin and stuck it in his eye socket to study the patterns it made.
Interesting that you see these as red and white- I see them as various intensities of cyan and white. I wonder what colors different people see, if it varies across the whole spectrum or only within a certain range.
I used to LOVE doing this as a kid.
I had RK surgery about 14 years ago, and I was told not to rub my eyes, so I haven’t done it in a long time.
Why do they continue for a few seconds after I relieve the pressure and open my eyes? When I just close my eyes and then reopen them, I can see everything around me instantly–but not when I apply pressure.