What is a concussion?

A concussion is a mild traumatic brain injury (mTBI) caused by a blow or jolt to the head or body that causes the brain to shake. The shaking can cause the brain to not work normally and can result in serious side effects. Each year, thousands of children and youth are diagnosed with concussion — only half are sports related.

Concussions can occur even when a child does not lose consciousness. In fact, only 10 percent of children with concussions report being “knocked out.” Some of the symptoms of a concussion can appear immediately after the injury, while others may not show up for several days. Symptoms may last days, weeks or months. Sometimes symptoms may be subtle and not obvious.

Signs and symptoms of concussion

The symptoms of a concussion are related to how well the brain cells are functioning and working together. The most common symptoms are related to four groups: physical, sleep, thinking/remembering, and mood disruption.


  • Headache
  • Nausea and vomiting
  • Balance problems
  • Slowed reaction time
  • Dizziness
  • Sensitivity to light
  • Sensitivity to sound
  • Fuzzy or blurry vision


  • Sleeping more or less than usual
  • Trouble falling asleep
  • Feeling fatigued or drowsy


  • Difficulty concentrating
  • Difficulty remembering
  • Confusion
  • Feeling “mentally foggy”
  • Feeling slowed down

Mood disruption

  • More emotional
  • Irritable
  • Sad
  • Nervous
  • Depressed

Often, symptoms will worsen over a matter of days, and it is common for new symptoms to appear in the days following the injury. Symptoms may also worsen when the brain is stressed, for example, when a child is doing schoolwork or participating in a physical activity.

This video about concussion symptoms answers questions such as: How do I know if I have a concussion? What are the signs of a concussion and when should I be concerned?

Pre-existing conditions and concussion symptoms

For children with pre-existing conditions, such as migraine headaches, learning disabilities, attention deficit disorder (ADD), attention deficit hyperactivity disorder (ADHD), visual disorders, and emotional and mental health conditions, concussion symptoms may be more severe or prolonged. It is important to know that a concussion may also worsen these underlying conditions and make them more difficult to control. Read more about the link between concussion and mental health.

When to call 911 after a head injury or suspected concussion

Call 911 if your child has any of the following symptoms:

  • Seizures (twitching or jerking movement of parts of the body; may look stiff)
  • Weakness or tingling in the arms or legs
  • Cannot recognize people or places
  • Confused, restless or agitated
  • Difficult to arouse or unable to awaken
  • Repeated vomiting
  • Blurred speech
  • Bloody or clear fluid from the nose or ears

Testing and diagnosis

Your child’s primary care provider will ask a lot of questions to understand how the injury happened and what symptoms your child is experiencing. The primary care provider will do a physical exam to test your child’s head-and-neck range of motion, balance, eye movement and neurocognitive ability.

There is not a single test to diagnose a concussion, but your child’s primary care provider may assess your child’s condition with a combination of tests. A physical exam will include eye tracking and balance tests. Cognitive testing can also help diagnose a concussion. Your child may be asked to play a memory game that challenges their “delayed recall” ability. Or, your child may be asked to take a computerized test to better understand how their brain is functioning.

Because a concussion affects the function of the brain, not the structure, you cannot see a concussion on brain imaging like a CT scan or an MRI. These tests only look for structural changes. 

Primary care providers will use all of the information they have gathered to diagnose and manage your child’s concussion.

CHOP clinicians and researchers have developed several cutting-edge tools to better diagnose concussion in youth, provide information regarding prognosis, and assess treatment outcomes. Learn more about the concussion diagnostic tools we continue to evaluate.

How do you diagnose a concussion? CHOP physicians explain:

What to do for a concussion

Your child should see their primary care provider if you think they have a concussion. The primary care provider can discuss symptoms and help you create a plan. CHOP Primary Care physicians are located in more than 30 locations across Southeastern Pennsylvania and New Jersey, and are especially equipped with training and diagnostic support tools for concussion.

After seeing your primary care provider, if you have further questions, please call CHOP's Sports Medicine and Performance Center at 215-590-6919, the Trauma Center at 215-590-5932, or Division of Neurology at 215-590-1719.

Physical recovery

Initial treatment for a concussion is rest, both mental and physical. Rest allows the brain to heal.

If your child has a concussion, they should not participate in activities that will exert her brain or body. Such activities may include:

  • Activities that could cause another head injury (such as sports, gym class, riding a bike, etc.)
  • Other physical activities that cause a sustained increase in your child’s heart rate and make her symptoms worse (such as any activity that causes them to break a sweat, lifting heavy items, etc.)
  • Activities that require a lot of concentration (attending school, doing homework, playing video games, texting, social media, etc.)

It is important to allow for sufficient brain rest (also called cognitive rest) so that the brain is able to heal. Allow your child to sleep as much as they need in the first few days after the injury. Your child should stay home from school until their symptoms are significantly improved. Reintroduce mental activity slowly as your child feels better. Your pediatrician can help guide this gradual process.

With guidance from your primary care provider, your child can slowly return to mental and physical activity as they begin to feel better.

It is important to watch your child closely, pay attention to their specific symptoms, and contact your physician with any concerns.

Learn more about the importance of cognitive rest after a concussion.

Emotional recovery

Full recovery goes beyond physical healing. Experts at CHOP have designed an evidenced-based website to help families with emotional recovery.

Follow-up care

During follow-up visits, your child’s primary care provider may redo some of the cognitive testing to see if concussion symptoms are improving or if other interventions are needed.

Common concussion questions

Our educational video series addresses some of the most common questions our concussion specialists hear from patients, parents, coaches and schools.

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