The brain-mind interface and alternate realities
It is said our consciousness is projected into this reality, through this living being that we become. This connection between the immortal or timeless Self and the physical body seems to brain (and nervous system) based.
Because when brain input-output signals are interrupted people experience alternate realities, ones have the qualities of being a real world, populated with strange beings, when compared to, say, dreams.
In other words, the consciousness can be freed to experience other worlds when it can no longer interface with this one.