How do you break the glass before using if you need what's underneath the glass to break the glass in the first place? In this way the koan exists to break through maya.
Look, consciousness doesn't appear in the brain, so neuroscience needs to research the opposite, starting with your basic nondualities.
Individual dreams are born. Universal dreams are reborn. Birth and rebirth are superimpositions on pure existence. Know that.
In the emptiness of the universe, a binary mind interprets disappearance as death and appearance as life, although all it knows from day zero is the existence principle.