Well, I have a book on Shamanism, but have only really dipped in and out of it. Just out of curiousity really. At one low point (and high point as far as drugs were concerned) the idea of Shamanism seemed rather attractive and I could relate to the concepts of spirits being attached to pretty much everything from a tree to a wolf and these spirits acting as our guide, protector and possibly even our nemesis.
I do find it rather interesting that an isolated group of humans has a tendency to look beyond the imediate. Our traditional forms of objective reasoning do not seem to apply within these tribes, intuition being paramount.
They connect to ' the invisible ' instinctively.
In a way, the early Christian congregations moved closer to this form of worship by applying faith to objective reality. When the Greeks & Romans observed the Christians they were baffled by their ability to accept God as being invisible yet capable of producing something out of nothing.
Greek & Roman philosophy is built up rationalizing what is visible (for the most part - from what I have read) and I think we in the West are part of that mindset. We have to be able to touch and measure to believe. There is little room for faith.
A Christian observes life as being underpinned by an invisible yet tangible spirit - a Shaman could relate to that concept, no doubt.
My thoughts are that faith impacts the psychology of a person and opens another dimension to ones personality and it takes faith to see beyond the imediate representation of matter and energy.
Anyway, I'm not sure where I am going with these thoughts now, so I'll clear off ! My mind gets chaotic at times and I sit in the middle trying to make sense of it all.