Watch Lizzie Borden Videos

UC Irvine neuroscientist James Fallon had already been studying the brains of psychopathic killers for years when his mother told him that he comes from a long line of murderers (including his infamous cousin, Lizzie Borden). After studying himself, Fallon discovered that he has two of the three ingredients for psychopathology. Fallon sat down with Reason.tv to explain why he's not a murderer, why others are.