Yogis and drugless highs

[Euphoric]

SWIM was thinking about some things he's heard about yogis and others who are well practiced in the art of meditation. Something striking was in regards to their capabilities of controlling internal functions, like slowing down heart rates and changing the temperature (blood flow?) to specific parts of their bodies. SWIM has heard of Tibetan monks who as a test must go to a mountain top with nothing but their basic monk attire and survive the biting cold only with the help of mental concentration to keep their bodies warm. He has also read of men in India who would bury themselves in the sand for months at a time, lowering their heartbeats to ridiculous levels. Another example of internal control SWIM can think of is selective regurgitation, like swallowing somethings, and then choosing something specific to bring back up.

Anyways, this made SWIM ponder some things. For example, could one learn to trigger an acute serotonin dump? Stimulate the pineal gland? Basically do the things drugs do, minus the drugs?

Any thoughts/theories? Has anyone been able to do similar things? Can anyone recommend a place to start learning about such meditation/self-control techniques?

Thanks