Interesting first-hand account here: I Visited the Church of Scientology; Here is What Happened, from The Federalist.
@mountaineer "Next, my friend and I were led to an E-meter machine, which passes a small amount of electricity through your body in an attempt to read how “strong” a particular thought, memory, or sensation is.
Our tour guide, named Kenny, handed me two can-like objects which were attached to the wires stemming from the E-meter. With my permission, he pinched me, and I watched as the needle on the machine ticked upwards on the screen. He explained this indicates this had a strong reaction in my reactive mind and that I needed to think about it a few more times to bring my experience out of the reactive mind and into the analytical mind.
I was asked to think about the pain again and again until the needle didn’t tick up as high on the reader. He told me that this was because I had rationalized the painful experience and all problems could be rationalized through auditing sessions. "
It's amazing that people fall for this kind of hokum.