4040. When the brain is denuded of the skull and the integuments that encompass it, there are seen therein wonderful circumvolutions and foldings, within which are situated the substances called cortical. From these run out fibers which constitute the medulla of the brain. These fibers proceed thence through the nerves into the body, and there perform functions in accordance with the orders and determinations of the brain. All these things are in exact accordance with the heavenly form; for such a form is impressed by the Lord on the heavens, and thence on the things that exist in man, and especially on his cerebrum and cerebellum.