For instance, when I get (got: my blood pressure is treated) migraine visual effects, I would say "lightning bolt" but thats just a textual analogue/simile. What I actually saw was more complex than that: lightning is white. My effect was polychrome.

When I had posterior vitreous detachment (PVD), the visual effect was as if I was looking at TV "snow" from the analogue days, combined with a shape unquestionably like red blood cells. Was I seeing blood? I am told no: I was seeing small points inside the focal zone of my eye, below the minimum resolving size, and the optical path turns points into rings.

So is "little people" moving stimulation of the nerve endings interpreted as "walking" and a strong vertical alignment for some reason? Is the colour an aspect of rods and cones being involved, or the nerves going to rods and cones being differentially effected?

Worth noting micropsia ("Alice in Wonderland syndrome") shows up in migraines and epilepsy too, so maybe the mushroom just hits a failure mode that's already wired in. Still, "evolved its own psychoactive pathway, and it's closer to porcini than to anything in Psilocybe" is a great sentence.