I'm reminded of the mechanics of Persinger's God Helmet when reading this. The helmet functions by magnetically overstimulating the left amygdala (responsible for fear/anxiety reactions) which causes it to dump it's neuro-electric load on the right amygdala responsible for reactions of bliss and the like. It's after that cross-over that 2% (or 20 people) reported having an encounter with God. As a side note, a much larger percent had entity contact of some kind, and it must also be assumed that under the scrutiny of rational scientist-types, volunteers might also be skeptical to reveal the full nature of a spiritual experience with the scientists. Whenever I've had a godhead encounter, it usually starts off with this sense of "impending doom" in the air. From a rational standpoint, I can always reassure myself that it's just a biological reaction of sorts, and that I'm not gonna die (at least in the literal sense) so that there's this sense of alarm and urgency where the inanimate objects in the room seem to be concerned for my safety cause I've "really done it this time" which after some intense build up transforms into an encounter with the godhead. So as you said, we must often go to hell to find heaven.