What Exactly Is CTE?
Chronic Traumatic Encephalopathy (CTE) is a progressive neurodegenerative disease, similar in some ways to Alzheimer's. It occurs when repeated trauma to the head causes a crucial protein in the brain, called tau, to malfunction. Instead of stabilizing
brain cells, the tau protein clumps together, slowly spreading and killing neurons. This process doesn't happen overnight; symptoms can take years or even decades to appear after the last head impact, leading to changes in thinking, mood, and behavior.
The Devastating Symptoms
The symptoms of CTE often appear in two waves. Early on, sometimes in a person's late 20s or 30s, they can manifest as issues with mood and behavior. This includes depression, anxiety, impulsive actions, and aggression. As the disease progresses, a second wave of symptoms can appear later in life, often around age 60. These are more cognitive, involving memory loss, confusion, and impaired judgment that can eventually progress to full-blown dementia. In its most advanced stages, CTE can impact motor function, causing tremors, balance problems, and difficulty speaking.
The Link to Football: A Disease of Repetition
The primary risk factor for CTE is repetitive head impact. This is why contact sports, and football in particular, are so closely associated with the disease. It's not just the violent, highlight-reel concussions that cause the damage. Scientists now believe that the thousands of smaller, sub-concussive hits that don't necessarily cause immediate symptoms are a major contributor. For a lineman, these can occur on nearly every play. Over a long career from high school to the pros, these impacts accumulate, triggering the destructive tau protein cascade in the brain.
The Sobering Statistics
At present, CTE can only be definitively diagnosed by studying brain tissue after death. Research led by Boston University's CTE Center has been central to our understanding of its prevalence. In one widely cited study, they examined the brains of 111 former NFL players and found evidence of CTE in 110 of them—or 99%. A more recent update from the center in 2023 reported that CTE had been diagnosed in 345 of 376 former NFL players studied, a rate of nearly 92%. Researchers caution that these numbers come from a self-selected group of families who donated brains, often because the player was showing symptoms. Therefore, it doesn't mean 92% of all former players have CTE, but it does confirm that the disease is shockingly common in this population.
What Is Being Done?
The NFL has implemented rule changes aimed at making the game safer, such as altering kickoff rules to reduce high-speed collisions and banning certain types of tackles. The league has also invested in research and improved concussion protocols. However, the biggest challenge remains diagnosing the disease in living patients, which is currently not possible. Researchers are actively working to develop diagnostic tools, like specialized brain imaging or biomarkers found in spinal fluid, that could one day identify CTE in the living. For now, treatment focuses on managing individual symptoms like depression or behavioral issues, as there is no cure.
