"Mike Marsh (Chapter 15) critically reviews assertions that NDE/OBE offer proof of extra-corporeal existence when the brain is supposedly “dead” or “clinically dead.” Marsh argues that studies have failed to produce corroborative empirical evidence for these assertions and that it is unclear how the memory required for recall could be set down with a properly dead brain at that critical time-point. He suggests that NDE/OBE occur as subjects are regaining full conscious-awareness and are analogous to hypnopompic dream awakenings. He points out that most recollections are intensely geo-physical, anthropomorphic, banal, and illogical: they provide nothing revelatory about life without a brain, or importantly, about other supposed cosmic contexts. There is also a marked chasm, Marsh argues, dividing NDE and the associated conceptualizations of “heaven” from true, classical spiritual encounters with the divine: the former are inconsistent with dogmatic (Christian) understandings of the afterlife and are decidedly not excursions of “souls” to some “heavenly” abode. Since prevalence rates are extremely low (< 1% globally), Marsh suggests that those undergoing NDE/OBE may have predisposed brains, genetically, structurally, or resulting from previous psychological stress."
(Loose, Jonathan J., Angus J. L. Menuge, and J. P. Moreland. "Introduction: Substance Dualism and Its Physicalist Rivals." In The Blackwell Companion to Substance Dualism, edited by Jonathan J. Loose, Angus J. L. Menuge, and J. P. Moreland, 1-21. Hoboken, NJ: Wiley, 2018. p. 15)
Note that Marsh is a theist himself:
"In introducing this chapter, I declared myself a monist in indicating my belief that human beings are integrated “psychophysical units.” Sustaining a stroke or vascular dementia informs us of the catastrophic cognitive and motor outcomes. The brain is the central coordinator of that psychophysical unit, while the “soul” could be envisaged as the emergent personality – encompassing body, developed mind, demeanor, vitality, extraversion or introversion, memory, planning for the future, conscientiousness, and so on. We, ourselves, are souls (Jeeves 1994, 134). Religious believers would wish to add a propensity for sin and guilt (Brown 1998), an apprehension of the divine and tendency for behaving spiritually. Cottingham (2005, 3–8) defines spirituality in terms of behaviors filling the creative and meditative space beyond material satisfactions, concerned thus with action not theory, ways of living rather than doctrinal allegiance, and praxis rather than belief. It is beyond truism that any part of the brain may be involved in religious experience (Saver and Rabin 1997). There is no cerebrally localized holy shrine, shrouded from the day-to-day vulgar commerce of secular neurophysiology.
Antithetically, true death is final and, eschatologically, must be firmly grasped. There can be no residual glowing embers, or “soul” like a beautiful butterfly emerging fromthe dried-up shrunken chrysalis of a corpse (Fiddes 2000, 66). Fiddes envisages a cosmic incorporation into Christ’s body where, ultimately, we shall finally come to see and knowourselves. My own view is that we shall be incorporated within the Godhead (Father, Son, and Spirit) through baptism. Baptism is here envisaged, within its cosmic and eschatological domains, as a “dying and rising with Christ”: a “re-birth” – “not of blood, nor of the will of man, nor of the will of the flesh, but of God” – and thus from “above”: an “adoption” anticipating ultimate union within the Godhead, in whom there is “perfect freedom.” Therefore we “rejoice that our names are forever enrolled into the heavens.” These and analogous quotations acquire meaning only in a metaphysical, rather than earthly, connotation (Marsh 2016b, 90– 97, 243– 249).
On these lines, it could never be convincingly argued that the recorded deposits of ND/OBE experience represent occasions on which, specifically, so-called “souls” leave the body on excursion to the “heavenly” realm, there to sample “divine presence.” Nor that this deposited archive affords cogent revelatory perspectives, hitherto unrevealed, concerning the life eternal. That is far more subtle a prospect than any ND/OBE report comes near to understanding or elucidating. I have been at pains to demonstrate the neurological underpinnings of much of the phenomenology undergone, believing it to represent reawakening phenomena during which extremely vivid illusory/hallucinatory material (hypnopompic) is conjured up by recovering brains – whatever the anterior physiologic insult. Critically, memory is necessary to facilitate later recall: and that can only occur during the wakening period but never when the brain is temporarily inactive due to preceding metabolic breakdown."
(Marsh, Michael N. "The Phenomenology of Near-Death and Out-of-Body Experiences: No Heavenly Excursion for 'Soul'." In The Blackwell Companion to Substance Dualism, edited by Jonathan J. Loose, Angus J. L. Menuge, and J. P. Moreland, 247-266. Hoboken, NJ: Wiley, 2018. pp. 262-3)
"We may philosophize well or ill, but we must philosophize." – Wilfrid Sellars