What if it's strictly anthropology and she's made us all out to be lunatics? I read an interesting book called (erm) 'Shamanism and neo-shamanism' (or something similar) recently, and it included interviews with gyrus, and quoted from the TMA, and all sorts. I felt like looking at animals in a zoo. It was interesting to see a different take on the kind of view-on-life many people round here presume 'normal'. Ah, found it it's Shamans/Neo-Shamans: Ecstasy, alternative archaeologies and contemporary Pagans by Dr Robert Wallis - interesting stuff. Not necessarily how people believe, but I'm sure you'd find it interesting.