You should be concerned about traumatic brain injuries because they can happen easily from any number of causes, such as an automobile wreck, a fall, a workplace accident, or non-contact sports, like bicycling. All that is required is a bump or a blow to the head, although a penetrating head injury, such as one from a bullet, qualifies as well.
Obviously, some people experience a bump to the head or a mild concussion and they recover completely. This may have happened to you or someone you know, maybe more than once. Unfortunately, not all traumatic brain injuries are so innocuous.
A person can suffer a closed head injury that is serious, but he or she might not experience any immediate, obvious signs that something is wrong. Sometimes the symptoms that signal a serious problem may not show up for days or even weeks.