In this week’s Medical Discovery News with UTMB’s David Niesel and Norbert Herzog: Swiss scientists found that when a hormone called erythropoietin (EPO) was elevated in the brains of mice, they were more active. EPO is the same performance-enhancing hormone banned by various sporting events and leagues, including the Olympics and the Tour de France. In the past 15 years, about 18 cyclists have died suddenly in their sleep from using EPO.