At the death of an individual, at first a biological event at this point in time, there is oxygen deprivation to the brain resulting in tunnel vision and euphoria, but this may be only the beginning of an overwhelmingly beautiful conscious event in which every individual 'meets and flows into' the Super-Conscious Unity.
This event could possibly tie together an individual's conscious moments into a 'four dimensional conscious node'; or a beautiful, unimaginable (at this point), conscious state that doesn't include any new experiences(and yet is not a prison), that is characterized by a powerful unifying glimpse of eternity.
An Individual's spirit therefore doesn't have to 'go' anywhere, but would reside in the same four dimensional physical space the individual has occupied their whole life.
This 'afterlife state' would therefore be a form of eternal life, not eternal consciousness (eternal consciousness being a never ending stream of conscious moments), and must also evolve in general; or in other words, be different for later (as well as earlier) conscious beings.
Only the SCU has eternal consciousness, although as sentient beings evolve closer and closer to the SCU, the distinction will become less and less clear. As to an eternal string of conscious experiences (eternal consciousness) for an individual who is not the SCU, it seems very unlikely.
Our conscious moments are eternal, but we probably don't have a never-ending string of them, since we did experience a beginning.
Correlating works, ideas or systems:
The large number of hauntingly similar 'Near Death Experiences' chronicled by everyone from your uncle to Carl Jung.
The extremely pervasive and critical idea (and promise) of eternal life throughout all cultures down through the centuries.
The question, "How would Alzheimer's disease patients go to 'Heaven' ?"