Yes, very definitely. The diagnosis of CTE, chronic traumatic encephalopathy, has definite criteria. For example, you have to see deposits of this abnormal protein called phosphorylated tau. It's quite easy to identify that protein because it stains a dark brown if the brain is prepared with the appropriate stain according to now-established techniques. Yes, we can identify brains that have that problem specifically.
For example, you may know the name Steve Montador. He played for six NHL teams during his career. We went over his records very carefully, and I personally counted that he had had 19 documented concussions. He was a very aggressive player. When he died unexpectedly at the age of 35, his brain had lots of deposits of this abnormal protein, which is very specifically located in areas that are characteristic of CTE.
The answer is yes. There are some people, even young people of 35 years of age, who are showing this abnormality after multiple concussions.