Brain injuries may result from motor vehicle accidents, assaults, falls, industrial accidents, sporting events, gunshot wounds and other incidents. Sometimes injury is caused by internal factors, such as surgery, infection or lack of oxygen to the brain, as in the case of stroke.

Over 1.5 million people each year experience brain injury. Of those, 80,000 experience physical disability requiring extensive rehabilitation. At least 1.3 million people a year experience mild brain injury and over half of them require some degree of rehabilitation.

Because of the brain's complexity, each person's response to brain injury can be different. Recovery depends on many factors, including the extent of damage, pre-injury personality and learning style, abilities prior to injury, age and amount of time that has passed since the injury occurred.

A person's support system (family, friends, employer, etc.) significantly affects recovery. Since recovery is a long-term process, those who have a strong support system stand a better chance of continuing to make improvements over a period of time, even after the formal rehabilitation process has ended.