In a fascinating interview Stanford University psychological anthropologist Tanya Luhrmann describes meeting modern day "witches", taking a "magic" course, experiencing bizarre (non-drug-induced) hallucinations and generally "hanging out in the magical world". Luhrmann also shares her thoughts on the biomedical model of psychiatry, her experiences spending time with evangelical Christians and the mechanism through which she believes individuals can enable themselves to have imagined conversations with God. She describes an example of a pastor telling her to pour herself a coffee and "a second cup of coffee for God" and how she believes there is a process where religious people learn to believe their thoughts are not "self authored" but rather they are "other authored". The discussion really starts to get interesting at about 17 minutes in:
Luhrmann's books “When God Talks Back” and "Persuasions of the Witch's Craft: Ritual Magic in Contemporary England" investigate how rational people come to believe and indeed experience the absurd.