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How Chronic Traumatic Encephalopathy Works


Concussion Repercussion
Ann McKee, professor of neurology and pathology at Boston University School of Medicine and co-director of the Veterans Affairs Center for the Study of Traumatic Encephalopathy, inspects a brain in the Bedford Veteran Medical Center.
Ann McKee, professor of neurology and pathology at Boston University School of Medicine and co-director of the Veterans Affairs Center for the Study of Traumatic Encephalopathy, inspects a brain in the Bedford Veteran Medical Center.
Stan Grossfeld/The Boston Globe via Getty Images

Since McKee and Omalu began their research into the connection between CTE and contact sports, professional sports organizations have been under pressure. In April 2015, the NFL settled a lawsuit with 5,000 retired players for $1 billion. The lawsuit claimed that the league had covered up evidence of the harm caused by concussions [source: Beck].

In the wake of that settlement, the NFL has implemented changes designed to reduce serious head trauma. These changes include banning tackles that injure the crown of the head. They're even thinking of changing the nature of tackling altogether, making it closer to the rugby style of grabbing legs. But as we now know, concussions are just the tip of the iceberg. Researchers are discovering CTE in the brains of deceased rugby players, hockey players and even soccer players [source: Branch]. It seems any activity that involves players getting repeatedly hit in the head, whether it's by other players or by soccer balls when heading, could have long-term consequences for brain health.

One recent study looked at the brains of 165 people who had played football at some point in their lives, whether it was in high school, college or the NFL. Of those, 131 had CTE — that's 79 percent — and 91 of them played in the NFL. Eighty-seven of those 91 pros had CTE — that's fully 96 percent [source: Beck]. Even if you account for the fact that people who donate their brains to research are probably more likely to have suffered from some disorder, those statistics are extraordinary.

A 2008 survey discovered that 4.6 percent of former NFL players had been diagnosed with Alzheimer's, dementia or some other memory-related condition. That rate is six times higher than the prevalence in the general population [source: Engber]. Whether these diagnoses are actually the result of CTE remains unknown, of course, and will remain so until after those surveyed die and are autopsied (if they are).

One problem with trying to find a way to prevent CTE from occurring is that, in the case of contact sports like football, it would seemingly require altering the game to the point of it becoming unrecognizable. Would football still be football if it didn't involve gladiatorial, head-crunching impacts? Would fans still be excited to watch it?


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