The arteries transport oxygen and nutrient-rich blood to the brain and a constant flow of blood is necessary for the health of the brain tissues and nerves. Information from California State University notes that the brain uses almost 20 percent of the blood in circulation and it requires approximately 25 percent of the oxygen in the body. The brain also needs a continuous supply of glucose for energy metabolism because it cannot store glucose, unlike other body tissues. During sleep, oxygen consumption remains the same though the flow of blood to the brain actually increases. The arteries to the brain and within it ensure that nourishing blood reaches all its nerves and cells.
The Carotid Artery
The internal carotid arteries run along each side of the neck after subdividing from the common carotid and subclavian arteries, which extend from the heart to the area of the collar bones. The internal carotid arteries carry blood to the brain while the external carotid arteries supply the face with blood. From the neck, the internal carotids pass behind the ear to the temporal or side lobes of the brain and then enter the subarachnoid space. In the inner brain the internal carotid arteries divide to give rise to other brain arteries. The internal carotids have twisting and turning pathways to the brain making it susceptible to plaque buildup and clot blockages. The Annals of Internal Medicine reports that the left internal carotid artery supplies the areas of the brain that control cognitive function in right-handed individuals and vice versa for left-handed individuals.
The Cerebral Artery
In the internal brain, the internal carotid arteries divide to become the anterior cerebral artery and the middle cerebral artery. The anterior cerebral arteries supply blood to the motor and sensory areas at the inner sides of the cerebrum, the uppermost and front areas of the brain that is involved in intellect, reasoning, understanding and other cognitive functions. The middle cerebral artery is a larger artery that has treelike branches to deliver blood to the outer sides of each hemisphere of the brain. This artery is important to supply blood to areas of the brain involved in speech, language and swallowing.
The Vertebral Artery
The two vertebral arteries ascend from the spinal column to the brain through the magnum foramen, a large opening at the base of the skull. Inside the brain, these arteries run along the brain stem and then join together to create an artery called the verterbro-basilar artery. These arteries follow fairly straight pathways and are therefore not as susceptible to blockages as other brain arteries. Other arteries branch off this looped artery to deliver blood throughout the brain.
