Neuroscientists scanned radicals’ brains to determine what makes them turn violent

The young man sitting in the waiting room of our neuroimaging facility wearing skinny jeans and trainers looked like a typical Spanish 20-year-old of Moroccan origin. Yassine* was bouncy, chatting up the research assistants, and generally in good spirits. He was like so many other Barcelona youths, except he openly expressed a desire to engage in violence for jihadist causes. As we took him through a battery of tests and questionnaires, we were barely able to keep him in his seat as he kept pro