is a brain injury that occurs from a blow to the head. But it's not just concussions that have researchers worried. Most scientists believe that CTE is a result of repeated, or sub-concussive, hits to the head. The concern is that each time the head takes a pounding, it shakes the brain inside the skull. All that sloshing around can lead to a buildup of an abnormal protein called tau, which can take over parts of the brain.
People like to point to safer helmets as a solution, but helmets can't do anything to protect your brain from sub-concussive hits. Imagine your brain like an egg; the shell is the helmet; the yolk is your brain. Just because you have a thicker shell, like an egg carton, doesn't protect the yolk from moving back and forth whenever the egg is shaken or moved around.
3. Football players aren't the only ones who need to worry about CTE
Despite all the talk about football players, they aren't the only ones concerned about CTE. The disease has been diagnosed in soccer
and baseball players
, and possibly even in military veterans
. In fact, the first mention of CTE was a disease in boxers called "dementia pugilistica" or "punch-drunk" syndrome in a 1928 issue of the Journal of American Medical Association.
The article said, "For some time, fans and promoters have recognized a peculiar condition occurring among prize fighters which, in ring parlance, they speak of as 'punch drunk.' Fighters in whom the early symptoms are well recognized are said by the fans to be 'cuckoo,' 'goofy,' 'cutting paper dolls,' or 'slug nutty.' "
4. No one knows how prevalent CTE is
Scientists can't say with certainty who will get CTE. They believe there maybe be genetic and environmental components at play. Researchers at Boston University have found 96% of ex-NFL players
suffer from the disease. But that doesn't mean 96% of all football players are at risk of having the disease. Remember, the disease has been studied in brains that have been donated by family members who suspected their loved ones may have CTE. It's not completely random -- it's known as selective bias.
5. There is no known cure for CTE
There's no way to diagnose it in living people. The only way to diagnose it is by autopsy. However, researchers hope that if they can identify it in living people, it will put them a step closer to understanding how the disease progresses and in turn lead them to a possible cure.
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