Any theory's on the affect Salvia has on human perception?

A few years ago I smoked some 20x about 10 times throughout the year. It had an overwhelming feeling of a cycle restarting. Like I've seen it all before some very fleshy and organic way. Like I was seeing a clock of sorts made of perpetual, spinning, human thought. Does this make any sense to anyone? Or in other words, are there any real theory's on the reasons behind these perceptions?