A lot of the time someone's life is in its last moments *because* the brain
is malfunctioning. And I don't see the likelihood of the brain performing
as it should if the whole system is spiralling toward its demise. The brain
seems to let go of all that it has in a last-minute attempt to avoid death,
so chaos ensues.
I sort of remember seeing something on TV about NDEs and how there's
usually a light at the end of a dark tunnel. The explanation that I
remember is that the occipital lobe (responsible for sight) is overloaded
with electrochemical activity, so what happens is that there's an intense
whiteness in the center of someone's field of vision and it becomes dimmer
towards the peripheral.
(sleep deprived,)
Mark