The cerebral vessels have a unique, perfect structure that perfectly regulates blood flow, ensuring the stability of blood circulation. They are arranged in such a way that when the blood flow to the coronary vessels increases approximately 10-fold during physical activity, the amount of circulating blood in the brain, with increasing mental activity, remains at the same level. That is, there is a redistribution of blood flow. Part of the blood from the brain regions with less stress is redirected to areas with enhanced brain activity.
However, this perfect process of blood circulation is disturbed if the amount of blood entering the brain does not satisfy its need for it. It should be noted that its redistribution across the brain regions is necessary not only for its normal functionality. It occurs also in the occurrence of various pathologies, for example, stenosis of the lumen of the vessel (constriction) or obturation (closure). As a result of impaired self-regulation, the rate of movement of blood in certain parts of the brain and their ischemia slow down.