Rick Strassman is a clinical associate professor of psychiatry at the University of New Mexico School of Medicine. From 1990 until 1995, he administered more than 400 doses of di-methyltryptamine (DMT) at varying strengths to nearly five dozen volunteers, in the first government authorized studies of psychedelic drugs in the United States since research was halted in the 1970s. Strassman found that the Eastern mysticisms provided both inexact phenomenological comparisons and inadequate theoretic models for his DMT data and he has more recently turned to biblical prophecy and its medieval Jewish understanding. DMT occurs naturally in the human pineal gland, and Strassman hypothesizes that its endogenous effects are consistent with the phenomena that he documented on the basis of its external administration. His book offers what he calls a "neurotheological" theory of prophetic experience. Although his book is addressed to DMT users, encouraging them to turn to the Bible and its medieval commentators for guidance, he is simultaneously offering a neuroscientific model of what used to be called "prophetic consciousness."