Most brain injuries are the result of an accident or an assault.
Injury to the brain may also occur any time oxygen to the brain is cut off, such as in a stroke, or because of infection. A closed brain injury occurs when the head hits another surface or is seriously jarred. An open brain injury occurs when an object penetrates the brain. The effects of a brain injury vary enormously depending on the area and extent of damage. The person may have difficulty learning, concentrating, comprehending , planning or thinking quickly.