The brain disease that the NFL has now acknowledged can be caused by playing football appears to be more widespread than originally thought, according to new scientific evidence that has alarmed some of the nation's top researchers.
The research, much of it published within the past year, includes brain bank studies that detected chronic traumatic encephalopathy, or CTE, in a large percentage of former high school football players and other athletes; scans that showed signs of the disease in NFL players decades after their retirement; animal models -- designed to replicate NFL-style head banging -- that suggest repetitive trauma can cause permanent brain damage; and a consensus statement issued by two dozen neuroscientists, who noted that CTE has "only been found in individuals who were exposed to brain trauma, typically multiple episodes.