A concussion is a traumatic brain injury that affects your brain function. Effects are usually temporary but can include headaches and problems with concentration, memory, balance and coordination. Concussions are usually caused by a traumatic blow to the head. Violently shaking the head and upper body can cause concussions as well.
Some concussions cause you to lose consciousness, but most do not. It’s possible to have a concussion and not realize it. Concussions are particularly common if you play a contact sport, such as football. The signs and symptoms of a concussion can be subtle and may not show up immediately. Symptoms can last for days, weeks or even longer.
Common symptoms after a concussive traumatic brain injury are headache, loss of memory (amnesia) and confusion. The amnesia usually involves forgetting the event that caused the concussion.
While concussion usually resolves on its own without lasting effect, it can set the stage for a much more serious condition. “Second impact syndrome” occurs when a person with a concussion, even a very mild one, suffers a second blow before fully recovering from the first. The brain swelling and increased intracranial pressure that can result is potentially fatal.
According to the Centers for Disease Control and Prevention, approximately 300,000 people sustain mild to moderate sports-related brain injuries each year, most of them young men between 16 and 25.