I have occasional visual blackouts that last about 4 seconds, probably something to do with blood flow.
Sometimes I'll also see these spots shooting all over the place that look solid enough I'll think they're bugs at first glance, but they're more like tiny points of grey light. Can't pin down exactly what causes that, but it's a purely visual hallucination. Once heard my great-grandmother saw "bugs" when dehydrated, and given my weird metabolism that causes me to sweat buckets, I could become relatively dehydrated at any time, so maybe it's that.
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No one in the world ever gets what they want,
and that is beautiful.
Everybody dies frustrated and sad,
and that is beautiful.
-TMBG