CTE found in nearly 90 percent of brains donated by football players

Research on 202 former football players found evidence of a brain disease linked to repeated head blows in nearly all of them, from athletes in the National Football League, college and even high school. It's the largest update on chronic traumatic encephalopathy, or CTE, a debilitating brain disease that can cause a range of symptoms including memory loss. "There are many questions that remain unanswered," said lead author Dr. Ann McKee, a Boston University neuroscientist.