Chronic Traumatic Encephalopathy



Chronic traumatic encephalopathy (CTE) is a deterioration of the brain. It is caused by the buildup of a protein called tau. The brain damage caused by CTE can lead to severe mental and physical disabilities. The condition gets worse over time.


Researchers have a found a link between repetitive head injuries and CTE. The head injury may involve:

  • A blow or jolt to the head
  • Severe jarring or shaking
  • Abruptly coming to a stop

Over time, these injuries can be associated with a build up of abnormal groups of tau proteins. These proteins can create tangled masses in the brain. The tangles can block normal brain function. Similar tangles are seen in people with Alzheimer disease.

Risk Factors

Having a history of head injuries puts you at risk for CTE later in life. Repetitive brain trauma (RBT) is the greatest risk factor for CTE. People who may be at the highest risk include those who:

  • Participate in contact sports, especially professional boxers, football players, hockey players, wrestlers, and soccer players
  • Have been in combat military service
  • Have been physically abused
  • Have severe seizures
  • Have a developmental disability and engage in self-abusive behavior (head banging)


Symptoms include:

  • Depression, including feeling suicidal
  • Paranoia
  • Aggression
  • Apathy
  • Irritability
  • Agitation
  • Impulsiveness
  • Poor concentration
  • Memory problems
  • Confusion
  • Poor judgment
  • Tremor
  • Muscle twitching

The symptoms may develop many years after the head injuries.


Your doctor will:

  • Ask about your symptoms.—It is important that you and your family members talk about any behavior or personality changes that you have had.
  • Take your medical history.—Your doctor will focus on your history of head injuries
  • Do a physical exam.

To gain more information about your brain and to rule out other conditions, your doctor may order tests, such as:

CT Scan of the Head

Breast self-exam, step 5
Copyright © Nucleus Medical Media, Inc.

At the present time, the only way to clearly diagnose CTE is for a doctor to examine the brain after a person has died. This is how researchers are learning more about CTE.


Treatment for CTE is an area that is being studied. Depending on your symptoms, though, your doctor may recommend:

  • Taking certain medications, such as antidepressants, antipsychotics, and mood stabilizers
  • Making lifestyle changes, such as exercising regularly, eating a healthy diet, and avoiding alcohol and drugs
  • Working with a therapist and joining a support group to help with the emotional challenges

You may be referred to a doctor who specializes in head injuries.


When playing sports, you can reduce your risk of CTE by:

  • Following your doctor’s instructions after suffering a concussion—This includes waiting to return to sports until your doctor says it is safe to do so.
  • Avoiding dangerous game play
  • Wearing proper protective equipment, such as helmets

Other steps that you can take to reduce head injuries off the field include:

  • Wear a helmet when doing any at-risk activity, like riding a motorcycle or bicycle, skiing, snowboarding.
  • Wear a seatbelt in the car.
  • Do not drink and drive or get into a vehicle with someone who is under the influence.
  • Make your home safe; for example, remove items that you could easily trip over and install night lights.
  • Get help right away if you are in an abusive relationship.


Boston University Center for Traumatic Brain Injury
Concussion Legacy Foundation


Ontario Brain Injury Association


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Published November 2010. Accessed November 10, 2017.
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Prevention: What Can I do to Help Prevent Concussion and other forms of TBI? Centers for Disease Control and Prevention website. Available at:
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Updated January 22, 2016. Accessed November 10, 2017.
Traumatic brain injury: hope through research. National Institute of Neurological Disorders and Stroke website. Available at: Accessed November 10, 2017.
Last reviewed November 2018 by EBSCO Medical Review Board Rimas Lukas, MD
Last Updated: 8/30/2013

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