"While it cannot be proved retrospectively that any experience of possession,
conversion, revelation, or divine ecstasy was merely an epileptic discharge,
we must ask how one differentiates "real transcendence" from neuropathies
that produce the same extreme realness, profundity, ineffability, and sense
of cosmic unity. When accounts of sudden religious conversions in TLEs
(temporal-lobe epileptics) are laid alongside the epiphanous revelations of
the religious tradition, the parallels are striking. The same is true of
the recent spate of alleged UFO abductees. Parsimony alone argues against
invoking spirits, demons, or extraterrestrials when natural causes will
suffice."
[Barry L. Beyerstein, "Neuropathology and the Legacy of Spiritual
Possession", The Skeptical Inquirer, Vol. XII, No. 3, pg. 255]