Head and neck anatomy may be important in the development of the BBB. Astrocytes may also be responsible for transporting ions (electrolytes) from the brain to the blood. Blood from the brain and neck flows from: (1) within the cranium via the internal jugular veins, a continuation of the sigmoid sinuses. The right and left external jugular veins drain from the parotid glands, facial muscles, scalp into the subclavian veins. The right and left vertebral veins drain the vertebrae and muscles into the right subclavian vein and into the superior vena cava, into the right atrium of the heart. The lymphatic system drains the
History of the location of the soul the heart does not need the brain to move. Galen recognized the importance of both the heart and the brain in the proper functioning of a human but saw these as two distinct system governed separately. Therefore there are two souls in combat, the brain representing the logical soul and driving logical being, the heart representing spirited actions of movement and impulse constantly at odds with each other and supplied by different supporting systems. Galen states the "liver is the archai" or the source of the veins and blood of the body and is therefore important in regards to the