Sarah Shourd, along with two fellow Americans, was arrested by Iranian officials during a hiking trip in the Zagros Mountains near the Iraq-Iran border in July 2009. In their new book, released Tuesday, the three hikers describe what it was like being in solitary confinement in an Iranian prison, NBC News reported. In, "A Sliver of Light: Three Americans Imprisoned in Iran," Shourd describes the mental anguish she endured living alone in a small room with a metal sink, bed and unrelenting fluorescent lights. "It erases you," she said of living alone in the cell. "It's like being buried alive. You can't talk to anyone, you can't laugh, you can't have a personality. Your world shrinks. It becomes smaller and smaller. Everything you know, everything you loved, seems far away. I would think about that person I once was. I would long for that person."