Neuroscience researchers from Boston University recently confirmed that former NFL player Dave Duerson suffered from chronic traumatic encephalopathy (CTE), a serious degenerative brain disease. Duerson committed suicide in February, leaving behind a note (and sending a text message) for his family, asking that his brain be donated to the CSTE Brain Bank, also known as the NFL Brain Bank.
Duerson is the latest example of several retired professional sports figures who have met early deaths due in part to CTE. As this sports blog at ESPN illustrates, there are a wide range of fervently held opinions regarding concussions on the playing field. Many comments accurately point out that hundreds of thousands of players (at school and collegiate levels) probably have been exposed to a concussion over the past several decades, with most players remaining cognitively intact over the long term.
So why the apparent disconnect between the rash of CTE symptoms in the NFL (and the NHL and the boxing world), and the relative lack of symptoms in the non-professional sporting world? I believe in time research will point at two variables: (1) repetitive head impact and (2) personal genetics.
My interview with the Chief Medical Officer of CogState points out the potential role of repetitive “subconcussive” head injuries (garden variety knocks on the head) in triggering an outsize inflammation response in the brain. Long term inflammation anywhere in the body is never a good thing.
The other variable can be stated like this: personal genetics will always trump strength and speed in the end. I think we will find out in the coming years that some people are genetically more prone to long term cognitive trauma caused by concussions. Some tantalizing research findings on CNS genes already point in this direction.
This also leads to the future possibility of screening for “concussion resistant” genetic profiles. In addition to pro sports, I can see how the military would find this capability useful. However, we’re still probably many years away from having a practical screening application on this.