There are lots of biochemical explanations for "mystical states". Many people on LSD or peyote claim to have mystical experiences.
Sure, it was the subject of my first research as it happens, and i have kept up to date with the literature. (And a quick interesting note -- I think Geoffrey PArrinder was completely right back in the late 60's to note there are, contra Wilber and others, actually two basic types of mystical experience - the monistic "I am he as you are he as you are me and we are all together." experience, and the "Encounter" experience more common in much of the mysticism of the Semitic religions - ego loss versus a feeling of encountering another cosmic ego (no joke intended!)
Mystical experiences can be produced by electrically stimulating certain locations in the brain.
If you can cite me a paper i'd be fascinated - I'm well aware of Persinger's work, but I'm afraid the failure of replication and the fact that people who do not know they are going to have a "mystical experience" don't - and indeed some who do, like Richard Dawkins f'rinstance when he tried it - does not fill me with confidence. Persinger strikes me as a great an brilliant guy, but still nowhere like demonstrating this.
There is absolutely nothing to suggest that such experiences have anything other than a biological origin.
There is absolutely nothing to suggest any experience has anything but a biological mechanism - that tells us nothing about the origin. If we see a rainbow, the experience is biologically mediated by the brain, as is eating an icecream - I don't think anyone doubts mystical states are mediated by the brain.
Best neurological mechanism I have seen suggested is that of d'Aquili and Newberg (1993, 1999) which is in theory falsifiable. Earlier models explain the monistic state as arising from something like a breakdown in the reciprocal relationship between the ergotropic and trophoptropic systems (Gellhorn, 1969). d'Aquili and Newberg suggest instead desire to eliminate thought in right prefrontal cortex passes impulses to right posterior superior parietal lobule, and from there to right hippocampus to the right amagydala, through to the ventromedial structures of the hypothalmus (part of the trophotropic system) then back to the right amagydala, the right hippocampus, and finally back to the right prefrontal cortex. (Wulff 2006) This describes what they think may have occurred in their study of Buddhist monks meditating: but while it describes perhaps - and it is far from definite - the neurology, they are careful to avoid ontological reductionism - the experience may be mediated this way, but that tells us nothing about the quality or value of the experience. They state
It is not obvious that the "objective reality" of ordinary consciousness has a higher ontological status than the "hyper lucid" an "highly integrated and integrating visions" of mystical experience (cited in Wulff,2006)
Like Jaynes (bicameralist) and Persingers hypothesis, I have doubts, not least because i am not convinced as I said that we are dealing with a single experience type. I can cheerfully talk about the subject for hours, but usually resist the temptation! I have never personally had a mystical experience. Maybe know you can see why!
Once again we come to the Great Divide between theists and atheists. Theists take belief in God as the default position and argue that one must take an active step in order to disbelieve. Atheists take nonbelief as the default, and it's belief that takes an active step. Each side continually fails to understand this about the other.
I'm not saying that atheism is about believing 100% there. 73% of atheists polled on RD.net disagree with the notion "I know there is no God". Only 26% were certain of that.
CJ, can I get you to indicate your understanding that "most atheists" (generalising, I know) do not feel that nonbelief is an active state? That for us, nonbelief is the default condition? I'm not asking you to actually accept it as factual, but can I get you to understand that we do?
Absolutely - I think such atheism is a perfectly sensible working assumption. The whole point of the thread was to falsify the theory theists are irrational (see other thread), and I regret using the term atheism at all. One does not have to demonstrate atheism irrationality ot render theism rational - I think both are perfectly rational...
cj x