Reddit mentions of Inside the Neolithic Mind: Consciousness, Cosmos and the Realm of the Gods

Altered states of consciousness can be achieved by many methods:Exhaustion, repetitive rhythms, dancing, drugs, vivid imagery and stories, music, staring into a fire. These are all used by shamans when they are attempting to 'commune with the spirits' (or whatever takes their fancy). This book has interesting things to say on the issue.

As Christians we need to be careful that we cannot be accused of influencing people by these methods (as a cult might), but there is nothing wrong using them to explore God's creation from an altered perspective