Paula Duncan looks for delirium, a serious problem that often goes undetected in older hospital patients. So Duncan, a registered nurse at Park Nicollet Methodist Hospital in St. Louis Park, Minn., has learned to look beneath the surface, including in patients’ dreams.

People who’ve experienced delirium often have horrific and haunting dreams, she says. It’s not always something they’ll readily talk about. She asks them how they’re sleeping and if they’re dreaming, and watches their faces for clues. “Sometimes you can see by the look on their face that they’re having this experience, but they don’t want to tell you because it’s so awful,” Duncan said.