Does anyone know of an online resource (or book) that goes through typical mental illnesses or neurological patterns that lead people to believe they've been possessed by demons? Google is swamped with religious blogs, and my google-fu is failing to cut through. Context: Somebody said (paraphrase) here's a youtube video of a guy acting kinda demonic, then everybody prays and he gets better. What is the "atheist" explanation? So I went around looking and didn't have much luck, and now I am really curious. I'm assuming that even if some are "fake," some people actually believe they are possessed. Also, yes, I know trying to convince a believer is probably a lost cause, but I'm curious for my own sake now.