Injury StatisticsApproximately 1.4 million people suffer a traumatic brain injury in the United States each year.1 Of these 1.4 million, 235,000 injuries are severe enough to require hospitalization and 50,000 cause death. More than half (over 700,000) of all these annual brain injuries result from sports-related activities, falls and physical assaults. In 2000, traumatic brain injury cost approximately $60 billion in the United States, in total in both direct medical expenses and indirect costs such as lost productivity. Functions The brain is your body's central processor, responsible for the critical functions that keep you alive: such as controlling your heart rate, breathing, and immune system. The brain also receives information about its surroundings through the senses: touch, taste, smell, sight, hearing and a sense of balance. Your brain processes this “sensory” information and sends signals to your muscles that make your body move in response to what was sensed. For example, if something moves near one of your eyes, the brain sends a signal to the muscles that control the eyelids, causing them to close and protect the eye. Your brain is housed within the skull, protecting the bone from direct impact damage. However, soft brain tissue essentially floats in a thin layer of fluid inside the skull and is close to the hard inner surface of the skull. For this reason it is possible to damage the brain indirectly. InjuriesBrain injuries can occur even without a visible injury to the head itself. There are 3 common types of brain injuries, defined by the amount of visible damage to the brain. These range from invisible trauma, to contusions with bruises, to widespread tissue damage (diffuse axon... middle of the paper... and other brain disorders that become more common with age. Due to the life-sustaining functions performed by the brain, death is always a possible outcome of any brain injury, which can occur within days, weeks, or even months after the initial damaging event. Mechanisms of InjuryTraumatic brain injuries occur with very rapid movement or arrest of the head can occur when the head hits a stationary object or is hit with a blunt object; either of these actions can cause the brain to collide with the inside of the skull created in the brain tissue and nearby blood vessels. The brain injuries discussed above can occur when these stresses are high enough. As the brain moves inside the skull, it can tear the blood vessels, causing intracranial hemorrhage.