have you read the book "the spirit molecule"? its about a doc who performed experiments with injecting people with dmt, that active agent in salvia. truly amazing stuff. the weirdest thing about it was that people had similar hallucinations and visions and saw very similar characters, tho none talked to each other or even knew who each other were. its like the entered into some other dimension, it wasn't just random weird hallucinations. but there was a sinister side to the whole thing, the clowns, they were freaky. anyway, you might really be interested in that book.