Traumatic brain injury is a common cause of permanent disability in patients who have had a serious automobile accident. The injury can affect mood, speech, mobility, vision and hearing. The part of the brain affected by trauma determines what kind of injury the patient has.
Some people have serious problems with agitation and aggression following a severe traumatic brain injury. The part of the brain affected can be the frontal lobe or the limbic system deeper in the brain. The trauma causes the damaged areas of the brain to make too many or too few neurotransmitters, resulting in changes in behavior.