The Centers for Disease Control and Prevention (CDC) shares there are approximately 1.5 million traumatic brain injuries² each year in the United States. Some accident victims are more fortunate than others and experience only mild TBI symptoms. They may even substantially regain brain function after the initial brain swelling from the trauma goes down.However, others will deal with lifelong issues, severe impairments, and an inability to participate in physical activity after a traumatic head injury. Here are common symptoms of TBI: