Whippoorwill, regarding your question above, the effects of trance states whether induced by music, singing, dancing, or other methods have been quite well studied. Check out the web site for the American Family Foundation. It will lead you to research at Ohio University's Cultic Studies Laboratory, as well as books by other researchers such as "Cults In Our Midst" by Margaret Singer. Music seems like such a completely benign experience, that we forget that anything, even music, can be used for manipulative purposes. Now that I know more about this power, I am more conscious of how easy it is for me to trance out when the celtic music at the session is pounding along. Especially when playing the bodhran, I find myself caught up in the beat and suddenly feel suspended in time, then become conscious that I have been in a trancelike state of mind. There is also a large component of feeling like "belonging" to the group in a special way.