It seemed like a textbook case of depression. The patient, a male in his late 30s, was in counseling for marital difficulties. He was socially withdrawn and had started drinking heavily. His speech and movements were slow. Yet even as he fought back tears in a session with his psychiatrist, Natasha Thomas, he could not describe how he felt. “When he would cry, I'd ask, ‘How are you feeling?' and he would shrug,” Thomas says. “I would give him words like, ‘sad, hopeless, frustrated.’” Her patient would reply, “What do those things feel like?”