Mac said: "Just as it says in the Gita, about pure consciousness being unable to be influenced or destroyed, yes, the witness of pure awareness, continues, through any permutation of awareness the mind is in - sleep, dreaming, intoxicated, awake...."
"BINGO!!! Yes, it is our eternal self, that lives beyond time and space." What is the role of the brain in Samadhi and higher states? Sparaig recently quoted MMY: "Every experience has its level of physiology, and so unbounded awareness has its own level of physiology which can be measured. … Everything is physical. Consciousness is the product of the functioning of the brain." This implies or opens the door to a model that Samadhi and higher states are achieved via neuroplasticity of the brain -- "culturing" and "refining" it in ways as to enable Samadhi, eventually on permanent basis. That is, the brain is "optimized" via new neural connections, long-term potentiation (persistent increase in synaptic strength following high-frequency stimulation of a chemical synapse) across existing neural pathways, changes in activation potential of long cascades of neurons, modification of mix, availability and persistence of neurotransmitters (NT), changes in NT receptors, etc. Which is a fascinating prospect. And might imply a genetic propensity towards Samadhi in some populations or families relative to others. That is, while everyone could culture Samadhi via systematic neuroplasticity methods, some may have a genetic head start -- the brain is already has some requisite pre-wiring. However, if Samadhi is brain dependent, then established Samadhi would not be sustained upon death of the body. And may not persevere with large changes to brain chemistry or structural changes from accidents or disease such as Alzheimers. And cessation of Samadhi at death would be inconsistent with significant portions of traditional literature, which in turn would then tend to place all statements in traditional literature in question. On the other hand, if Samadhi is not brain dependent, then what are physiological / brain research on meditation / yoga measuring? And why would the body or brain matter in modalities to culture Samadhi? These questions keep me awake at night.