C&EN tackles chronic traumatic encephalopathy

Lauren Wolf looks at scientists trying to track the accumulation of tau (and other signs of CTE) in vivo: 

...One question they’d like to answer is how much brain injury a person can handle before CTE sets in. With support from the Nevada Athletic Commission and local fight promoters, the group is gathering data by periodically testing its fighters and comparing them with a control group of age- and education-matched people who have never had head trauma. When the test subjects visit the Lou Ruvo Center, they update their fight records, take cognitive tests, and lie down inside a magnetic resonance imaging machine. 

“We’re looking at a variety of MRI modalities,” Bernick explains. He isn’t yet sure which combination of MRI scan types will be most useful for detecting CTE-related brain damage and tracking it over time, so his group is running a full battery of them. 

A few have shown promise so far. Volumetric MRI, which constructs a three-dimensional view of the brain, has indicated that subjects who fought more bouts during the study’s first year had greater tissue loss in regions of the brain called the corpus callosum and putamen. The corpus callosum is a bundle of nerve fibers that connects the right and left hemispheres of the brain, and the putamen is a structure deeper within the brain that helps regulate movement and learning.
The results of diffusion tensor imaging, another type of MRI, also suggested that some of the study’s fighters have a thinning corpus callosum. This type of imaging maps the 3-D movement of water throughout the brain. Water typically flows parallel to nerve fibers, so when that flow pattern changes in a particular brain region, scientists take it as a sign of neuronal damage in that spot.

[snip]

...Four years ago, when Robert A. Stern was writing grants for a large-scale CTE study, he says it was far-fetched that scientists would be able to see phosphorylated tau in the living brain anytime soon. “Much to my delight, there are a couple groups who have now done it,” says Stern, a neuropsychologist at Boston University who collaborates with McKee. 

Stern is working with one of the groups, now at Eli Lilly & Co. subsidiary Avid Radiopharmaceuticals, to test a tau radiotracer in retired NFL players. The trial has been tacked onto Stern’s larger study, called DETECT (Diagnosing & Evaluating Traumatic Encephalopathy using Clinical Tests), which is comparing participants with a control group of age-matched athletes, such as baseball players, who never played contact sports... 

I am really disturbed at the mounting scientific evidence that some contact sports are actively harmful to players' brains. Here's hoping that, over the years, we can understand if all or just some individuals tend to get CTE and why. Is there a correlation between sport/position played and likelihood of CTE diagnosis? How long does it take before CTE sets in? (The article says that it has been detected in high school athletes.) Yikes.

Am I crazy, or did most folks know Chris Benoit as just "Chris Benoit"? I never heard the "Canadian Crippler" nickname until now.