What is a concussion?

Video narrated by Concussion Legacy Foundation CEO Dr. Chris Nowinski

A concussion is a type of traumatic brain injury caused by a bump, blow, or jolt to the head or by a hit to the body that causes the head and brain to move rapidly back and forth. Rapid movement causes brain tissue to change shape, which can stretch and damage brain cells. This damage also causes chemical and metabolic changes within the brain cells, making it more difficult for cells to function and communicate. Since the brain is the body’s control center, the effects of a concussion can be far-reaching.

Concussions are usually not life-threatening, but the effects of a concussion can change a life and the injury should be treated seriously.

More common than we realize

The CDC estimates as many as 3.8 million concussions occur in the U.S. annually through sports and recreational activities, however only a fraction are recognized by athletes, coaches, parents, and are treated by medical professionals.

Concussions can occur in any sport, during practice or competition. In fact, according to a 2019 study by the Journal of Pediatrics, 36% of all diagnosed high school sport concussions occurred during practice, with Cheerleading being the only sport with a higher rate during practice than competition.

Teenagers are especially vulnerable to concussion. A 2017 survey of teenagers by the CDC found that 2.5 million teenagers experienced a concussion in a sport or recreational activity, and 1 million teenagers reported two concussions in the previous year.

Signs and Symptoms of a Concussion

The signs and symptoms of a concussion are incredibly important because a concussion doesn’t show up on imaging like an x-ray, CT, or MRI scan and there is no objective test, like a blood or saliva test, that can determine if a patient has a concussion. A doctor makes a concussion diagnosis based on the results of a comprehensive examination, which includes observing signs of concussion and patients reporting symptoms of concussion appearing after an impact to the head or body. Concussion signs and symptoms are the brain’s way of showing it is injured and not functioning normally.

Concussion Signs

Concussion signs are what someone could observe about you to determine if you have a concussion. Signs of a concussion range from obvious to much more nuanced, but even one sign of a concussion after a hit to the head should be reported to a medical professional.

Common concussion signs include:

  • Loss of consciousness
  • Problems with balance
  • Glazed look in the eyes
  • Amnesia
  • Delayed response to questions
  • Forgetting an instruction, confusion about an assignment or position, or  confusion of the game, score, or opponent
  • Inappropriate crying
  • Inappropriate laughter
  • Vomiting

Concussion Symptoms

Concussion symptoms are what someone who is concussed will tell you that they are experiencing. Concussion symptoms typically fall into four major categories:

1- Somatic (Physical) Symptoms

  • Headache
  • Light-headedness
  • Dizziness
  • Nausea
  • Sensitivity to light
  • Sensitivity to noise

2- Cognitive Symptoms

  • Difficulties with attention
  • Memory problems
  • Loss of focus
  • Difficulty multitasking
  • Difficulty completing mental tasks

3- Sleep Symptoms

  • Sleeping more than usual
  • Sleeping less than usual
  • Having trouble falling asleep

4- Emotional Symptoms

  • Anxiety
  • Depression
  • Panic attacks

Note: This is not an exhaustive list of concussion signs and symptoms, and it may take a few days for concussion symptoms to appear after the initial injury.

Concussion Response

If you suspect a concussion in an athlete, it is extremely important to remove that athlete from play immediately so they can be evaluated by a trained professional. A 2018 University of Florida study found that among college athletes across 18 sports who ceased activity once they were injured missed three fewer days of competition than those who delayed reporting. Additionally, immediate removal from activity reduced concussion symptoms by about two days and decreased the likelihood of missing more than two weeks of participation by 39 percent. To learn more about what you should do after a concussion, visit our Concussion Response page.

After removal from play, doctors recommend physical and cognitive rest for a few days following a concussion, or until you see a medical professional. Hear from Dr. Robert Cantu, medical director of the Concussion Legacy Foundation, about why the brain needs rest after it has been injured:

Complex Recovery: Post-Concussion Syndrome

Recovering from concussion means your brain cells must return to the normal function by rebalancing levels of chemicals, like sodium and calcium, inside and outside of the cell. This process takes a lot of energy, so it is important to conserve energy during recovery. When properly managed, the majority of concussion symptoms will resolve within a couple of weeks, however over-exertion of brain cells during recovery can cause symptoms to persist for months or even years. A significant percentage (estimates vary between 10% and 30%) of concussion patients suffer from extended recovery, known as Post-Concussion Syndrome

Finding the right doctor to help you with your concussion is key to making a full recovery. To help you find treatment in your area, we developed our Concussion Clinics Tool. Just type in your area code and find specialized concussion treatment near you.

The importance of prompt concussion reporting inspired our Team Up Speak Up campaign. The goal of Team Up Speak Up is to make sure that every youth athlete knows that being a good teammate means getting them help as soon as they might have a concussion. Sign your team up for Team Up Speak Up today.

Catastrophic re-injury: Second Impact Syndrome

During recovery, the brain is more vulnerable to re-injury. In rare cases, a second concussion sustained during recovery can cause the brain to undergo massive swelling. This extremely rare condition is known as Second Impact Syndrome (SIS). Approximately half of SIS patients die from their injuries, and the survivors often suffer from life-long disability.

Read the heartbreaking stories of Rowan Stringer and Nathan Stiles to learn about young athletes who lost their lives to SIS.

A preventable epidemic

The good news is we can stop concussions before they happen. There are many opportunities to reduce concussions through smart policy decisions. Research has shown more than half of all head impacts and concussions in football occur during practice; in middle school soccer players there are 100,000 concussions caused by heading every three years. The Concussion Legacy Foundation has led the movement to reduce hitting in football practices at the youthcollege and professional levels. Our Safer Soccer campaign led to a rule change in soccer that prohibits players 10 and younger from heading the ball and reduces headers for 11 to 13-year-old players. There is still a lot to do to make sports safer for all athletes and the Concussion Legacy Foundation will continue to be on the forefront of research and education.

Leading to a Safer Future

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