and x gets the square

Boogaard had chronic traumatic encephalopathy, commonly known as C.T.E., a close relative of Alzheimer’s disease. It is believed to be caused by repeated blows to the head. It can be diagnosed only posthumously, but scientists say it shows itself in symptoms like memory loss, impulsiveness, mood swings, even addiction.

More than 20 dead former N.F.L. players and many boxers have had C.T.E. diagnosed. It generally hollowed out the final years of their lives into something unrecognizable to loved ones.