An insidious, microscopic protein that has been found in the brain tissue of professional football players after death may now be detectable in living people by scanning their brains.
Researchers say they found tau protein in the brains of five living retired National Football League players with varying levels of cognitive and emotional problems.
"It's definite, we found it, it's there," said Dr. Julian Bailes, co-director of the NorthShore Neurological Institute in Evanston, Illinois, and co-author of a new study that identified the tau. "It was there consistently and in all the right places."
Using a scan called positron emission tomography, or PET -- typically used to measure nascent Alzheimer's disease -- researchers injected the players with a radioactive marker that travels through the body, crosses the blood-brain barrier and latches on to tau.
What has stymied researchers for years is that tau can only be uncovered after death. Finding it in living players is considered by many researchers to be the "holy grail" of concussion research, according to Bailes.
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