“The same mechanism that enhances our creativity – juicing up the right-sided limbic and prefrontal brain regions with dopamine – also opens us up to religious ideas and experience. But if these brain circuits are pushed too far, thinking becomes not merely divergent but outright deviant and psychotic.”
http://aeon.co/magazine/world-views/dopamine-marks-the-line-between-religious-believer-and-fanatic/