What Is a Concussion?

A concussion is a mild form of traumatic brain injury (TBI) that can occur from a bump, blow, or jolt to the head. Depending on the severity, they can cause temporary loss of consciousness. Concussions are relatively common among people of all ages, but young children, the elderly, and young adults (especially teen athletes) are the people most likely to get a concussion.

In 2019, there were approximately 223,135 hospitalizations related to traumatic brain injuries in the United States—and these were just the people who sought medical care. It is estimated that 1.6 to 3.8 million sports-related concussions occur in the U.S. every year.

Because every concussion—no matter how mild—should be seen by a provider, it’s important to know how concussions occur, what symptoms to look for, and how to prevent and treat them.


Each person who sustains a concussion will have a different set of symptoms; some people may have many symptoms while some only have one or two. Surprisingly, loss of consciousness is actually not a common symptom of concussion, only occurring in about 10% of cases. 

The typical symptoms of concussion can be separated into four groups:

  • Physical: Headache, dizziness, nausea and/or vomiting, sensitivity to light and sound  
  • Cognitive: Confusion, forgetfulness, inattentiveness, inability to follow directions
  • Emotional: Anxiety, depression, irritability, mood swings
  • Sleep: Sleeping too much or too little, inability to fall asleep

Which symptoms you experience depend on a variety of factors, including how severe the concussion is and where on the head it occurred. Some symptoms may occur immediately and some may not appear until days or weeks after the initial injury.

What Causes a Concussion? 

In a concussion, the brain moves quickly back and forth within the skull, usually as a result of a blow or bump to the head or a sudden jolt to the body. This causes chemical changes and, in some cases, damage to brain cells, which leads to the symptoms frequently associated with concussions.

The most common causes of concussions are:

  • Falls
  • Being hit by an object or crashing into an object or person
  • Physical fights or assaults
  • Motor vehicle accidents
  • Sports injuries

Risk Factors

The people most likely to get a concussion include people over the age of 75, babies, and toddlers aged 4 and under, and young adults between the ages of 15 and 24. Males are at a higher risk than females.

While young children and the elderly are more likely to get a concussion from an accidental injury (like slipping and falling), young adults are most at risk if they play a sport. In the United States, as many as 300,000 sports-related concussions occur each year, with more than 60,000 of them caused by contact sports in high school. Football and soccer, in particular, carry higher than average rates of concussion for high school and college-level players.

How Is a Concussion Diagnosed?  

Diagnosing a concussion usually only involves a physical exam by a trained healthcare provider. The provider will assess a person’s hearing, vision, and balance, as well as other cognitive symptoms—like memory loss and confusion—while asking questions about the injury that occurred.

In most cases, a computerized tomography (CT) scan or magnetic resonance imaging (MRI) isn’t required since they won’t show evidence of a concussion. A provider will usually only order these diagnostic tests if concussion symptoms are severe and they need to rule out a more serious side effect, like swelling or hemorrhage. In these cases, you’ll likely be referred to a  neurologist (a medical doctor specializing in the brain, spinal cord, and nervous system) for further treatment.


Unfortunately, there’s no quick fix to treating concussion: a combination of rest and symptom management will allow the brain to heal. It usually takes about seven to 14 days for this to happen, but some people need up to one month to fully heal.

It is extremely important to seek medical care after a head injury of any kind. Concussion severity varies significantly. Your healthcare provider will be able to provide a treatment plan that is best for your individual case.


A short period of rest followed by a gradual increase in light activity is usually the best way to begin recovery from a concussion. In the first few days, you should not do any strenuous activity and make an effort to avoid any activities that pose a risk of re-injury. Reinjuring yourself while you have a concussion puts you at high risk of complications and negative long-term effects.

Once symptoms start to improve, you can add in small amounts of activity at home (while still taking care to avoid injury and get plenty of rest). Then, once symptoms become mild or start to resolve, you can make a gradual return to work or school with some accommodations (i.e. planning to take as many breaks as needed and keeping your workload and stress minimal). 

It’s important to practice both physical rest and cognitive rest; it may be some time before a young athlete can resume practicing or playing sports, and an extended break from strenuous mental activities, like studying and test-taking, may also be needed, especially if they increase symptoms like headache and fatigue.

At the same time, experts no longer recommend that all physical activity be restricted in the days and weeks after a concussion: if you are feeling well enough, light activity such as walking may actually speed up the recovery period.

Symptom Management

There isn’t a lot that can be done to reduce or improve symptoms such as dizziness, fatigue, or memory loss. If you are experiencing headaches, over-the-counter pain relievers can be used. Your provider may recommend Tylenol (acetaminophen) rather than non-steroidal anti-inflammatory drugs (NSAIDs) such as Advil (ibuprofen) to reduce your risk of bleeding. It’s also important to stay hydrated and eat whatever foods your stomach can tolerate.

If concussion symptoms linger and begin to affect your quality of life, seeing a behavioral health therapist, physical therapist, or occupational therapist can help with some of the physical, cognitive, and emotional side effects.

How to Prevent a Concussion

Concussions can’t always be prevented—accidents happen, and sports injuries are a part of most players’ careers, even as teens and young adults. However, there are some best practices for preventing TBIs, which include:

  • Practicing motor vehicle safety (i.e. wearing a seat belt and never driving under the influence of drugs or alcohol)
  • Wearing a helmet when participating in high-risk or contact sports, or riding a motorcycle, bicycle, or other ride-on vehicles
  • Securing the home environment so it’s safer for elderly adults or babies and toddlers

For sport-related concussions, there are a few additional tips that can reduce the likelihood of TBI:

  • Increasing concussion education, including symptom awareness, for coaches, trainers, parents, and all players
  • Encouraging a positive sports culture around injuries, so players feel safe speaking up about suspected concussions
  • Making and enforcing rules designed to keep players safe
  • Having the right equipment for the sport, keeping it in good condition, and making sure it fits all players properly

Comorbid Conditions   

Until recently, there wasn’t a lot known about the relationship between concussion and other health conditions. However, researchers are now discovering that concussion does increase your risk for several physical and mental health conditions, including long-term conditions:

  • Cardiovascular disease: People who have had a concussion are more likely to have subsequent cardiovascular disease and hypertension. This may be, in part, because concussion is linked to weight gain, fatigue, sleep disorders, and reduced physical activity. 
  • Endocrine disorders: Traumatic brain injuries may cause damage to the pituitary system, which can lead to endocrine disorders like type 2 diabetes. A 2022 study suggests that this might be one reason why the rate of type 2 diabetes in veterans is so high. 
  • Neurological disorders: Because of the damage to the brain after a concussion, the risk for neurological conditions such as stroke and epilepsy increases. The risk of developing Alzheimer’s disease is also heightened post-concussion.
  • Psychiatric conditions: Emotional symptoms are common in people with a concussion, and these can persist or worsen in the long term. The rates of psychosis, sleep disorders, substance use disorders, anxiety, and depression are all higher in people who have had a concussion.

Living With a Concussion  

A concussion isn’t a lifelong or permanent condition; eventually, the brain heals itself and symptoms resolve. During that time, it’s important to follow the treatment protocol prescribed to you by your healthcare provider and get sufficient rest. 

Rarely, concussion symptoms continue past the usual timeframe. If your symptoms are still lingering after three months, you may be diagnosed with postconcussive syndrome, though this only happens in about 10% to 15% of cases. Postconcussive syndrome is also typically not a permanent condition: while your symptoms may last longer than normal, most people fully recover in three months.

Again, the goal is to manage your symptoms using the treatments recommended to you by your provider and try to be as patient as possible while your brain heals. 

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17 Sources
Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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