Dr. Ann McKee and more than 120 million other Americans watched Sunday's Super Bowl between the Seattle Seahawks and the Denver Broncos. However, it's likely none did so with her perspective as the nation's leading expert on the effect of contact sports on the brain.
"I'm just worried," she said. "I'm just worried about their long-term health. I don't want to see what I've seen in other individuals happen to them."
McKee, an Appleton native and a 1975 University of Wisconsin-Madison graduate, has worked as a neuropathologist at the Edith Nourse Rogers Memorial Veterans Hospital, outside of Boston, for the last two decades. Five years ago, in the morgue where she had autopsied thousands of brains of America's veterans, she received her first brain from a former NFL player.
"I had never seen degenerative disease that severe in a 40-something-year-old, and that just blew my mind," she said. "This should be a disease that only hits people when they get really old, but this disease comes in (their) mid-life, right at the prime of their life."
The disease she discovered was chronic traumatic encephalopathy. Since that initial discovery, the families of dozens more athletes in football, hockey, soccer and rugby have donated their loved ones' brains to McKee's lab to discover whether CTE would explain in death what they witnessed in life.
"They have personality changes," McKee said. "They become irritable and volatile. They can become very aggressive and impulsive. They can become suicidal. They can have difficulties with headaches and judgment."
Throughout her career, McKee has studied a protein called tau that is found in the brain in patients with degenerative diseases like Alzheimer's and Lou Gehrig's disease. Her autopsies have shown a large amount of tau in former players' brains, at the bottom of the cortex as well as in abnormalities clustering around blood vessels.
She said one of the leading hypotheses is that repetitive head trauma triggers an aggressive reaction from people who may be genetically predisposed to getting Alzheimer's disease. So instead of getting the disease in their 80s, they may get it in their 40s and 50s instead.
To the critics, including those in sports who don't want to change the status quo, she remains steadfast in her research. Confusing CTE with normal aging or Alzheimer's disease -- the two most common criticisms of her work -- is ignorant, in her opinion.
"That's like mixing up a car and a piece of fruit," she said. "Those are two crazy, different things. I do get the sense we've sort of lifted a veil that was really hidden to us for quite some time, and that's a paradigm shift. This is a disease that doesn't just happen naturally. We've never seen this disease in a person who didn't get their head banged."
As far as today's parents deciding what sports to allow their children to play, she does not feel comfortable offering recommendations, except to say she values the emotional, mental and physical benefits while simultaneously understanding the risks.
"I couldn't be a more strong supporter of sports in general, but I think we have to be smart," she said. "We have to be careful that we're not getting away from ourselves, that we're not risking our children's long-term health for success in the sport that they're playing."
One look around her office reveals a passion for both pathology and the Packers. There are replicas of the brain and bobblehead dolls of Green Bay players, like quarterback Aaron Rodgers. She said she's having trouble reconciling her love of football with her knowledge of what can happen to its players.
"I grew up a football fan. Football is huge in my family. I feel like it's in my blood," she said. "I don't see any way (CTE) doesn't change football. I don't see any way this doesn't impact how the game is played."