What is a concussion?

A concussion is a mild traumatic brain injury caused by a bump, jolt, or blow to the head. The sudden movement causes the brain to bounce around or twist inside the skull. This leads to stretching and damaging of brain cells and chemical changes in the brain. A jolt to the body can also cause a concussion if the impact is strong enough to cause the head to forcefully jerk backwards, forwards, or to the side.

A concussion is classified as "mild" because it is not usually life-threatening. However, the effects from a concussion can be serious and last for days, weeks, or even longer.

What factor does age play in concussion risk?

Adolescents are at higher risk because of their developing brains. The high school athlete has a greater risk than the college athlete, and the college athlete a greater risk than the professional athlete.

What causes a concussion?

Motor vehicle accidents, falls, and sports injuries are common causes of concussions. Any sport that involves contact can result in a concussion.

Among children, most concussions happen on the playground, while bike riding, or when playing sports such as football, basketball, or soccer.

What are the symptoms of a concussion?

The most common symptom of a concussion is a headache. This is an especially serious symptom if the headache gets worse over time, which might mean that there is bleeding in the skull.

Other symptoms include:

  • nausea
  • balance problems/dizziness
  • double or blurry vision
  • sensitivity to light and noise
  • fatigue or drowsiness
  • changes in sleep patterns
  • trouble comprehending and/or concentrating
  • depression
  • irritability, nervousness, or sadness
  • feelings of being "just not right" or in a "fog"

Other danger signs are:

  • seizures
  • not knowing people or places
  • unusual behavior

In children, the signs to seek emergency treatment include:

  • any of the adult symptoms listed above
  • will not stop crying or calm down
  • will not nurse or eat

When do concussion symptoms appear?

Concussion symptoms usually appear within minutes of the blow to the head. Some symptoms may take several hours to appear. Symptoms can change days later; others can develop when the brain is stressed by such activities as reading or running.

When should an athlete with a possible concussion go to the emergency room?

A loss of consciousness (greater than one minute), a neck injury, or symptoms such as weakness or numbness that persists are reasons to send the athlete to the emergency room.

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