A 67-year-old retired teacher in Kentucky was on the verge of asking for an exorcism after she started seeing oblong faces with large teeth, eyes and ears hovering over her. Doctors confirmed she wasn't on drugs, and wasn't losing her mind. The woman said she knew the hallucinations were not really there, and they didn't speak to her. In fact, the woman's macular degeneration had triggered a peculiar condition called Charles Bonnet syndrome, which causes some people suffering from eye disease to start to see animals, creepy faces or other illusions. "When [the brain] expects sensory input and receives nothing, it often creates its own input," said Dr. Bharat Kumar, an internal medicine resident at the University of Kentucky who treated the woman. Oftentimes, the hallucinations stop once the brain gets used to less visual input, according to the case report, published in February in the journal Age and Aging.