The soul gathers the powers of life to itself, and descends with them into the heart. As life leaves the eye, and returns to its source within the soul, the eye no longer sees... As life leaves the mind, and returns to its source within the soul, the mind no longer thinks. As life leaves the skin, and returns to its source within the soul, the sense of touch is lost. 'By the light of the heart the soul leaves the body; and as the soul leaves, the powers of life follow. Since the soul is consciousness, the body loses consciousness as the soul departs; and the soul carries the spiritual effects of all that the person has done, experienced and known.'
Brihadaranyaka Upanishad 4:1-2