I think its more of a trick of the eyes, I've had it off pills before, I've had it off sleep deprivation and weed aswell, objects that are really there have more pronounced features, especially in the dark and u'll find it striking in its resemblence to summat completely out of scene, once I was stoned out of my mind, and I saw an olde tyme horse a chariot, as I approached it is was just a Ford fiesta...........I laffed, worst time was on shrooms, watching apocalypse now, u know the bit at the end, when he's walkin out of the temple Brando's in, and all those tribemen are there, for about 5 mins I was contemplating whether they were tribesmen, or a cornfield blowin in the wind, I decided on a cornfield, and it turned out to be tribesmen, and I'd seen the film about 3 time before that
Don't worry ureself, overactive imagination man