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URL of this page: https://medlineplus.gov/lab-tests/concussion-tests/

Concussion Tests

What are concussion tests?

Concussion tests can help find out if an adult or child has had a concussion after a head injury. A concussion is also called a mild traumatic brain injury (mTBI).

A concussion happens when sudden movement causes the brain to bounce around or twist inside the skull. It can be caused by a bump or blow to the head. It may also happen if a hit to the body causes the head and brain to move rapidly back and forth. This jolting movement can create chemical changes in the brain. And it can stretch and damage brain cells.

Even though a concussion is a "mild" brain injury, it can seriously affect the brain. Most people don't lose consciousness when they have a concussion. But some signs and symptoms usually show up right away after the injury and others may appear hours or days later. Symptoms are different for each person, but often include headaches, problems with memory, and changes in how a person thinks, acts, feels, and sleeps.

The symptoms of a concussion are usually temporary. With treatment most people feel better in a couple weeks. The main treatment is physical and mental rest. Without proper rest, recovery from a concussion may take longer.

There are many types of concussion tests that health care providers use to help diagnose concussions. They usually include questionnaires that you fill out and tests of mental and physical abilities. Some tests have special versions for children. All concussion tests have scoring systems that help show how much an injury has affected the brain. The tests check:

  • How well your brain processes information. This includes testing memory, problem solving, and other brain functions. These tests are often done on a computer or on paper.
  • How well your nervous system is working. These tests check balance, muscle coordination, and other physical abilities. A provider often does these tests as part of a physical exam.

A concussion will not show up on imaging tests that take pictures of the brain. So, these tests usually aren't needed to diagnose a concussion. But a CT or MRI scan of the brain may be done if there are signs of a more serious brain injury, such as bleeding in the brain.

Some concussion tests are designed for sports coaches or trainers to use with athletes of all ages who have hurt their heads playing sports. These tests are sometimes called "sideline assessments." They are not a substitute for a medical examination after a blow to the head.

Other names: concussion assessment

What are they used for?

Concussion tests are used after a head injury to see if the injury is affecting brain function. The tests are also be used to monitor recovery after a concussion.

Athletes, including student athletes, may have a routine concussion test at the start of the sports season even when they haven't had a brain injury. This is called a "baseline test," and it's usually done by a trained health care professional.

The purpose of baseline testing is to have a record of the athlete's normal brain function. Later on, if the athlete has a head injury, a provider can compare the baseline test results with the results of a concussion test done after the injury. This helps to:

  • Confirm or rule out a concussion
  • Find out how severe a concussion is
  • Know when an athlete is fully recovered and ready to return to normal activities

Baseline concussion tests are mostly done on athletes who play contacts sports that have a high risk for concussion, such as football and hockey.

Why do I need concussion testing?

You may need concussion testing if you have had a head injury or a blow to the body that jolts your head. Testing may be necessary even if you think the injury isn't serious. That's because it's possible to have a concussion and not even know it.

Concussion symptoms usually show up soon after a head injury. But sometimes, they don't show up for hours or days. So, it's important to keep watching for signs and symptoms of a concussion for a day or two after a head injury. Signs and symptoms of a concussion include:

  • Appearing dazed or stunned
  • Clumsy movements
  • Answering questions slowly
  • Headache
  • Nausea or vomiting
  • Fatigue
  • Confusion
  • Dizziness
  • Sensitivity to light and/or blurry or double vision
  • Changes in sleep and/or mood
  • Difficulty paying attention
  • Memory problems

In rare cases, a dangerous blood clot can form on the brain a day or two after a head injury. This is a medical emergency. Call 911 or go to an emergency department right away if a child or adult has one or more of these symptoms:

  • A headache that gets worse or doesn't go away
  • Weakness, numbness, decreased coordination, or seizures
  • Repeated vomiting
  • Slurred speech and/or unusual behavior
  • One pupil (the black part in the middle of the eye) that's larger than the other
  • Confusion
  • Not being able to wake up, a loss of consciousness, or looking very drowsy

For infants and toddlers, the symptoms of a medical emergency are the same as for adults and children, but also include:

  • Crying that won't stop
  • Not eating or nursing

What happens during concussion testing?

To do concussion testing a provider will usually use one or more standard concussion tests to learn about the injury and how it's affecting the brain. During the testing you'll usually:

  • Answer questions about the injury, such as:
    • How the head injury happened
    • Whether the injured person was unconscious and for how long
    • Signs and symptoms after the injury
  • Take a test, often on a computer, to check for problems with:
    • Learning
    • Memory
    • Thinking and reasoning
    • Ability to pay attention
  • Have a physical exam that checks for problems with:
    • Vision and eye movement
    • Hearing
    • Balance
    • Coordination
    • Reflexes

In certain cases, your provider may order a blood test to help decide if a brain scan is needed to check for a more serious injury. The test checks a blood sample for certain proteins that may show up in the bloodstream after a mild concussion. To collect a blood sample, a health care professional inserts a small needle into a vein in your arm and collects a small amount of blood into a test tube or vial.

Will I need to do anything to prepare for a concussion test?

You don't need any special preparations for concussion testing.

Are there any risks to the tests?

There's little risk to having concussion testing. If you have a blood test, you may have slight pain or bruising at the spot where the needle was put in, but it usually goes away quickly.

What do the results mean?

If concussion testing shows that a head injury has caused a concussion, the treatment is physical and mental rest to help the brain heal. This often includes limiting time spent on electronic screens (televisions, computers, phones, and tablets). It may also be necessary to take two or three days off from school or work.

Ask your provider about a recovery plan, including how to relieve symptoms. As symptoms improve, physical and mental activities can gradually be increased. But it's important to make sure that the concussion is fully healed before returning to all usual activities. That's because having a second concussion before the first has healed can cause serious brain damage. Your provider may do another concussion test to see if recovery is complete.

Complete healing is very important for athletes who want to return to their sport after a concussion. Different sports organizations may have "concussion protocols" that set guidelines for when an athlete can participate again after having a concussion.

Learn more about laboratory tests, reference ranges, and understanding results.

Is there anything else I need to know about concussion testing?

Concussions are common among children and young adults. Adults age 75 and up also have a higher-than-average risk of concussion because they have a higher risk for falls. But there are steps you can take to prevent concussions at any age, including:

  • Wearing the correct helmet and making sure it fits when you or your child play sports such as, biking, skiing, skating, hockey, football, and batting in baseball or softball
  • Wearing seat belts
  • Preventing falls by keeping your home well-lit, removing tripping hazards, and using nonslip mats and grab bars in the bathroom
  • Making home and play areas safe for young children:
    • Making sure playgrounds have shock-absorbing material, such as mulch or sand
    • Installing window guards
    • Using safety gates on stairs
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The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.