What is a concussion?

A concussion is a brain injury that is caused by a sudden blow to the head or to the body. The blow shakes the brain inside the skull, which temporarily prevents the brain from working normally.

Some people have obvious symptoms of a concussion (such as passing out or feeling lightheaded), while others do not. With rest, most people fully recover from concussions within a few hours to a few weeks.

On rare occasions, concussions cause more serious problems. Repeated concussions or a severe concussion may require surgery or lead to long-lasting problems with movement, learning, or speaking. Because of the small chance of permanent brain problems, it is important to contact a doctor if you or someone you know has symptoms of a concussion.

What causes a concussion?

Your brain is a soft organ that is surrounded by spinal fluid and protected by your hard skull. Normally, the fluid around your brain acts like a cushion that keeps your brain from banging into your skull. However, if your head or your body is hit unexpectedly hard, your brain can suddenly crash into your skull and temporarily stop working normally.

There are many ways to get a concussion. Some common ways include fights, falls, playground injuries, car crashes, and bike accidents. Concussions can also happen while participating in rough or high-speed sports such as football, boxing, hockey, soccer, skiing, or snowboarding.

What are the symptoms?

It is not always easy to know if someone has a concussion. Not everyone who has a concussion passes out. A person who might have a concussion should immediately stop any kind of activity or sport. Becoming active again before the brain returns to normal functioning increases the person's risk of having a more serious brain injury.

Symptoms of a concussion range from mild to severe and can last for hours, days, weeks, or even months. If you notice any symptoms of a concussion, contact your doctor.

Symptoms of a concussion include:

• Passing out.
• Not being able to remember what happened after the injury.
• Acting confused, asking the same question over and over, slurring words, or not being able to concentrate.
• Feeling lightheaded, seeing "stars," having blurry vision, or experiencing ringing in the ears.
• Not being able to stand or walk; or having coordination and balance problems.
• Feeling nauseous or throwing up.

Sometimes it can be hard to tell if a small child has a concussion. If your child has had a head injury, call your doctor for advice on what to do.

Occasionally a person who has a more serious concussion develops new symptoms over time and feels worse than he or she did before the injury. This is called post-concussive syndrome. If you have symptoms of post-concussive syndrome, call your doctor. Symptoms of post-concussive syndrome include:

• Changes in your ability to think, concentrate, or remember.
• Headaches or blurry vision.
• Changes in your sleep patterns, such as not being able to sleep or sleeping all the time.
• Changes in your personality such as becoming angry or anxious for no clear reason.
• Lack of interest in your usual activities.
• Changes in your sex drive.
• Loss of your sense of taste or smell.
• Feeling that you are spinning, whirling, falling, or tilting. These describe vertigo, or a sensation that you or your surroundings are moving when there is no movement. Vertigo may make you lightheaded or nauseous, and you may throw up. You may also have trouble standing or walking and lose your balance.