Football has long since been recognized as a dangerous sport, but for long, and for most, this view was held in reaction to frequent sprained ankles and torn ACLs. In recent years, however, awareness surrounding the dangers of football-related head trauma have come to the forefront. Concussion protocol in professional sports has increased. Players are treated with extra caution when displaying concussion like symptoms, and coaches are advised not to put their players back in the game because the dangers of concussions are known.
As dangerous as concussions are, the ultimate result of repeated head trauma can be even more devastating. CTE, (chronic traumatic encephalopathy) is a progressive, degenerative brain disease heavily correlated to football-related head trauma.
While scientists have found a correlation between football and this disease, we know that correlation does not always equal causality. Scientists have, however, developed a plausible mechanism for the development of the brain disease. Nadia Kounang draws a parallel between the brain inside of the skull and an egg inside of a shell to illustrate how the disease is contracted from sub-concussive impact. The brain is suspended in fluid inside your skull, much like the yolk of an egg that sits within the whites of the egg. When severe impact is made, the brain sloshes back and forth within the fluid. This repeated movement is damaging for the brain and leads to the development of CTE (Kounang). Furthermore, Kounang notes that harder helmets or more padding cannot prevent the brain from being damaged. For example, putting a dozen eggs in a carton may prevent them a bit from breaking, but cannot stop the yolk from moving back and forth within the shell (Kounang).
After reading this one source, I tried to find a more definitive answer as to how CTE is developed, as the first only provided the analogy between brain and egg. I wondered if a confounding variable could be at work. For example, could CTE be due not necessarily to the being hit in the head but perhaps wearing helmets that are tight on the skull. mayoclinic.org, though, notes that players of all sports are at risk. The back and forth movement of the brain causes a protein called tau to build up surrounding the blood vessels, which deteriorates brain functioning and damages nerve cells, a main symptom of CTE (Wexler). By the end of CTE’s development, the state of the brain is fully altered from its original state.
The tau buildup in the brain of a CTE patient mirrors that of an Alzheimer’s patient; football is the fast track to Alzheimer’s related symptoms. While the repeated head trauma does ultimately cause CTE, the tau buildup is an intermediary. This is to say that repeated blows to the head cause the tau protein in our brains to clump together and clout, which advances the symptoms of CTE.
The next issue is dealing with how to recognize CTE in a living brain. Up to now, recognition of tau build up in CTE-diagnosed brains only happened after the player had died. Tau is in all human brains. It is the deposits and clots of tau that are extremely dangerous, the hard endpoint.
In order to judge how much head trauma affects tau buildup in the brain, scientists studied the brains of five retired NFL players and five control brains. The brains of the NFL retirees had much higher levels of tau deposits in their brain. The deposits were mostly found in the amygdala, a part of the brain that dictates fear and anger (Roth), which corresponds with the second stage of CTE, as pictured above (Wexler).
While this is a very small study, paired with the standing belief that tau deposits could cause CTE, I think it is very promising. I would like to see a much larger control study in which the brains of retired NFL players are compared to control brains of say, white collar workers. This could lead to concluding that it is too unlikely for chance to be at work. As such, it could be confirmed through a large control study that head trauma causes tau deposits, and tau deposits cause CTE.
Identifying the link between tau deposits and CTE is crucial, because scientists believe they have found a correctional method by which they can prevent the loss of tau’s function in the brain (Roth). With deaths of football retirees increasing, a study such as this that finds correctional means may be able to silence the rising sentiment that football is too dangerous to play.