‘Alter’ is not the right word (tho it also is). Before we apply the meditation, the system is already altered, what we call ‘conditioned’ (also known as, entrenched). What Osho’s active meditations do is de-condition the system. So yes, there is ‘an alteration’, but it is a reversion back to baseline.

Again to use the term ‘to alter brain chemistry’ is a bit loose because even tho the final result will be an alteration in the brain chemistry, the method with which the change is achieved (with Osho’s active meditations) is thru the physical manipulation of the body … rather than (let’s say) direct chemical, err… assistance.

These days, I am hearing that Osho’s active meditations were a combination of bio-energetic exercises (from the growth movement) mixed with eastern traditional meditation methods. Back in ‘80s, the stories I used to hear were that Osho ‘borrowed’ the techniques from a snake cult in the north of India but I cannot find any references to it. The hoo part of Dynamic in definitely sufi.