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What is a brain injury?

Traumatic Brain Injury

What is a Traumatic Brain Injury?

A traumatic brain injury, also called a TBI, occurs when brain function is altered by an external force. This can happen when something strikes the head, the head hits something, or a jolt causes sudden brain movement.

What are the different types of traumatic brain injury?

Brain injuries may be classified as mild, moderate, or severe to indicate the initial severity of the injury.

Concussion or Mild TBI (mTBI): An mTBI is also commonly referred to as a concussion. In this case, “mild” refers to the fact that concussions are not generally life threatening. Symptoms of an mTBI can include a brief loss of consciousness, vomiting, lethargy, and memory loss. Learn more about concussion here.

Moderate TBI: A moderate TBI is classified by a loss of consciousness for up to 24 hours, signs of injury that show up on neuroimaging, and signs of brain trauma.

Severe TBI: The key indicator that someone has a severe brain injury is a loss of consciousness for more than 24 hours. Severe brain injuries also often have more severe and persistent symptoms.

What causes a TBI?

A TBI is caused by an external force and can come from many different sources. Common causes of TBI include:

  • Falls (the leading cause of concussions)
  • Assaults
  • Motor vehicle accidents
  • Sports
  • Combat

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If you or a loved one has sustained a TBI, the Brain Injury Association of America is here to help.

  • The Brain Injury Specialists at our National Brain Injury Information Center (NBIIC) are ready to answer any and all questions that you have. To get in contact with them, call 1-800-444-6443 or fill out our contact form.
  • Our publication Moderate to Severe Brain Injury: A Practical Guide for Families contains a wealth of information on how to navigate recovery after brain injury.
  • The Resource Center on our website contains dozens of articles on a wide range of topics from getting financial assistance to how to deal with specific symptoms.