Brain damage was diagnosed in 87 percent of donated brains of 202 football players, including all but one of 111 brains of National Football League athletes. This new study, published today in the journal JAMA, is the latest linking dangerous head injuries to football, though the authors note that the true risk may be lower than the results suggest. Chronic traumatic encephalopathy, or CTE, is the term for brain damage that occurs after repeated blunt impact, like head tackles in football. Previous research has shown that CTE is linked to — among other things — memory loss, depression, and dementia,...