Megan Scudellari @ Bloomberg Businessweek reports on a recent study, involving a handful of athletes, that found merely one season of high-school football, even without concussions, leads to noticeable brain abnormalities. All it takes for brain changes to occur is a number of “small, successive blows to the head” — damage that affects learning and memory. The study leaves open a series of unanswered questions, including long-term damage concerns.