What Is CTE? NFL's Vincent Jackson Had Disease Linked to Head Trauma When He Died

NFL star Vincent Jackson had chronic traumatic encephalopathy (CTE) at the time of his death, his family have said.

Jackson, a former wide receiver for the San Diego Chargers and the Tampa Bay Buccaneers, was found dead in a hotel room in Florida in February this year. He was 38 years old.

His cause of death was not immediately clear, but his family have told The New York Times that the NFL player was diagnosed with CTE, a degenerative brain disease, after his death.

CTE is found in people who have a history of repetitive trauma to the head and brain, such as athletes who play contact sports, according to the CTE Center in Boston University.

The effects of CTE have been recorded in boxers since the 1920s, when it was known as "punch drunk syndrome." In more recent years, cases have been confirmed in active and retired football and hockey players. The disease has also been found in people who did not play sports after high school or college.

CTE occurs when repeated brain trauma leads to the malfunction of a protein called tau. This malfunction causes a chain reaction in other proteins and the damage spreads throughout the brain.

The progress of CTE can be slow and it may take years for symptoms to emerge after head impacts. Symptoms associated with the disease include memory loss, confusion, impaired judgment, impulse control problems, aggression, depression and eventually progressive dementia, according to the Boston CTE Center.

Research is being undertaken in order to find out more about how CTE progresses, how to diagnose it and what the risk factors are. It is unclear, for example, how many hits to the head are needed to cause degenerative changes to the brain or what type of impact would do this.

CTE cannot be diagnosed in living people. It requires a neuropathological examination of the brain tissue, according to Dr. Ann McKee, director of the VA-BU-CLF Brain Bank at Boston University School of Medicine, which studies the disease using a large collection of donated brains.

Often, CTE can cause a personality shift, McKee says in a YouTube explainer for the Concussion Legacy Foundation. According to The New York Times, Vincent Jackson's widow Lindsey Jackson agreed to speak out about the condition in order to help families of other former football players spot CTE's effects.

"I think the message is, if you played for a long time and you're experiencing symptoms, it's very likely that this is what it is," she told the newspaper.

On Tuesday, it was reported that CTE may have been a factor in the case of Phillip Adams, a former NFL player accused of shooting and killing six people in April this year. Adams then took his own life.

If you have thoughts of suicide, confidential help is available for free at the National Suicide Prevention Lifeline. Call 1-800-273-8255. The line is available 24 hours every day.

Vincent Jackson
Vincent Jackson, seen here playing with the Tampa Bay Buccaneers against the New Orleans Saints in September 2015. Jackson had CTE at the time of his death, his family have said. Wesley Hitt/Getty