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What is a concussion?

A concussion is a type of traumatic brain injury that is caused by a blow to the head or body, a fall, or another injury that jars or shakes the brain inside the skull. Although there may be cuts or bruises on the head or face, there may be no other visible signs of a brain injury.

You don't have to pass out (lose consciousness) to have a concussion. Some people will have obvious symptoms of a concussion, such as passing out or forgetting what happened right before the injury. But other people won't. With rest, most people fully recover from a concussion. Some people recover within a few hours. Other people take a few weeks to recover.

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It's important to know that after a concussion the brain is more sensitive to damage. So while you are recovering, be sure to avoid activities that might injure you again.

In rare cases, concussions cause more serious problems. Repeated concussions or a severe concussion may lead to long-lasting problems with movement, learning, or speaking. Because of the small chance of serious 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. But if your head or your body is hit hard, your brain can crash into your skull and be injured.

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 any sport or activity 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. You don't have to pass out (lose consciousness) to have a concussion.

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 fit into four main categories:

  • Thinking and remembering
    • Not thinking clearly
    • Feeling slowed down
    • Not being able to concentrate
    • Not being able to remember new information
  • Physical
    • Nausea and vomiting
    • Headache
    • Fuzzy or blurry vision
    • Dizziness
    • Sensitivity to light or noise
    • Balance problems
    • Feeling tired or having no energy
  • Emotional and mood
    • Easily upset or angered
    • Sad
    • Nervous or anxious
    • More emotional
  • Sleep
    • Sleeping more than usual
    • Sleeping less than usual
    • Having a hard time falling asleep

Young children can have the same symptoms of a concussion as older children and adults. But sometimes it can be hard to tell if a small child has a concussion. Young children may also have symptoms like:

  • Crying more than usual.
  • Headache that does not go away.
  • Changes in the way they play or act.
  • Changes in the way they nurse, eat, or sleep.
  • Being upset easily or having more temper tantrums.
  • A sad mood.
  • Lack of interest in their usual activities or favorite toys.
  • Loss of new skills, such as toilet training.
  • Loss of balance and trouble walking.
  • Not being able to pay attention.
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