You are a non-physical being and chose to have this temporary human experience. Only a small part of your consciousness is focused in this physical experience, with the greater part of You always remaining in non-physical.
When your physical body dies the part of You that has been focused here will re-merge with your Higher Self in non-physical.
The physical brain acts as an interface connecting your non-physical Self to the physical body, in much the same way that a radio translates non-physical radio waves into the sound we can perceive with our physical sense of hearing.
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