Comment by guessmyname

Same here. I also recall them when I had fevers in my childhood.

I attribute them to the fact that, while trying to sleep with a fever, my eyes are half-open, and any sharp object becomes a visible geometric shape that my brain attempts to comprehend but almost fails to. I still experience them in adulthood. I’ve never had sleep paralysis, but whenever I think of people who have it, I imagine it feels as debilitating as these half-sleep experiences where you’re unable to move while your brain processes distressing memories.

“Geometric Nightmares” is not a scientific name. It is simply the name given to this phenomenon in forums [1][2] where people discuss and share their experiences.

[1] https://www.reddit.com/r/Dreams/comments/7ofu86/x/

[2] https://www.reddit.com/r/geometricnightmares/