(…) Mark’s condition is called hyperacusis. It can be caused by overexposure to loud sounds, although no one knows why some people are more susceptible than others. There is no known cure. Before the onset of his symptoms, Mark lived a life that was noise-filled but similar to those of millions of his contemporaries: garage band, earbuds, crowded bars, concerts. The pain feels like “raw inflammation,” he said, and is accompanied by pressure on his ears and his temples, by tension in the back of his head, and, occasionally, by an especially disturbing form of tinnitus: “You and I would have a conversation, and then after you’d left I’d go upstairs and some phrase you had been saying would repeat over and over in my ear, almost like a song when they have the reverb going.” (…)