Andras Bilkei-Gorzo welcomes people to his laboratory at the University Hospital of Bonn. In addition to all sorts of instruments, there are computers here. This is where he evaluates the data he gets from his research. One of them was recently published in a professional journal. Together with other researchers, Bilkei-Gorzo investigated how small doses of cannabis affect the brains of rats. They found that it reverses brain aging and increases cognitive abilities. He talks to Dennis Scherer about this.