Altered awareness states
The ancient Buddha, Siddartha, is said to have self-induced mild to deep allegedly lucid reduced awareness (i.e. coma) states (called the 4 Jhanas) by gradually reducing his focal (meaning contact response) range (hence consciousness) from wide-angle (i.e. selecting a lot of stressor responses) to narrow angle (i.e. selecting a few stressor responses), to on-end (i.e. selecting one stressor response) and finally to no-end (i.e. avoiding any stressor response, thus avoiding re-birth) and which produced, so he claimed, awareness (itself a response, hence itself a stressor) of emptiness,* Sanskrit: sunjata). He self-induced the various selective awareness (i.e. coma) states firstly to eliminate (i.e. de-select) contact with the world, both outer and inner, and to which he (possibly an Asperger’s syndrome victim; note he showed now signs of personal warmth though plenty of cool non-directed compassion) appears to have responded with chronic stress = suffering, and, secondly, to achieve euphoria (to wit, “the bliss of liberation” (possibly from distress, possibly from its cause)).
Likewise, some ancient Hindus (i.e. the Vedantins) claimed that the deepest restricted awareness (interpreted as sleep/coma) state (called: turīya, i.e. the ‘fourth’) brought about euphoric oneness of the self, i.e. the atman, with the Self, i.e. the Brahman, meaning one’s personal self as all, because alone.
Recent experiments into normal human sleep/coma states have discovered 4 distinct brainwave patterns that happen during ordinary (or induced) sleep (likewise in hypnotic and meditation induced selective awareness/non-awareness). That might suggest that there is no fundamental difference between normal sleep (general reduced awareness) and artificially induced (i.e. by means of hypnosis, meditation or barbiturates) sleep/coma.
The Scottish East India Company surgeon James Esdaile performed more than 300 hundred major surgical operations on patients he or his helpers induced into a highly reduced = deep (actually lucid, because the subjects claimed later on that they were not unconscious) coma (meaning selective unawareness) state by means of mental misdirection (i.e. mesmerism)). His surgical operations appeared to have been pain free. Moreover, post-operative infection was reduced to a minimum and which suggest further experiments into the affect of normal and induced (via, for instance, barbiturates) coma states on immune system functioning. On his return to England, Esdaile’s medical peers ridiculed him and rubbished his technique (don’t they always!) probably because he failed to prove his point by being unable to reproduce the profound selective non-awareness (i.e. coma) state he had been able to induce back in India.
In the 1950’s, genial American hypnotists like David Elman, Gil Boyne and Milton Erickson regularly induced the Esdaile deep coma/sleep state (to wit, the 3rd Jhana). Indeed, Elman claimed that he could induce an even deeper coma/sleep state, and which he called hypno-sleep.
* A note for those who have chosen any one of the 84.000 pre- or post- modern Buddhists selective non-awareness (hence non-rebirth) paths to personal liberation. Hearsay has it that the Buddha (and who never called himself Buddha but chose the name Tathagata) originally understood ‘empty’ to mean: ‘empty of abiding substance or essence’ (to wit: Pali: atta, supposedly meaning self), meaning: impermanent (Pali: annica). Later on and following the deliberate ad absurdum reduction of all traditional Buddhist dharmas by the loony Mahayana Buddhist scholiast Nagarjuna (born and educated a Brahmin, a true 5th column saboteur), the content of emptiness, namely ‘abiding substance or essence’, was dropped so that the bland and meaningless surface structure notion of ‘emptiness’ (as such) remained. By so doing the initial (deep structure) emptiness focus was reduced/flattened so that it could be freely generalised, indeed universalised. The more intense response to the reduced notion of emptiness was equated, falsely, with both full awakening (Pali: samma-sambodhi) and full liberation (but not enlightenment). This sorry (Occam’s Razor like) reduction from more to less (so that the less could be generalised to more = all) can be clearly observed in the full version of the Heart Sutra. Nagarjuna’s deliberate, dastardly reductionism reduced Buddhism’s distinctive because unique message to nil. A few centuries later Buddhism had completed disappeared from India and the Brahmins once again ruled as top dogs.