You’re in a classroom and the teacher puts an exam face down on your desk. You pick it up and can’t really make out what’s on it; it’s blurry, or it’s in another language, or it’s in a subject you didn’t study. You feel like you’re going to fail, even though it’s been years since you’ve actually been in school. People commonly relive this scenario in their dreams, even decades after their last graduation. While many high school, college and graduate school students are cramming for real exams this week, you may dream about it if you have anxiety about being judged, or if you’re in a situation you don’t know how to handle, experts say. Dreams are “an extremely rich source of practical advice, and other alternatives about what we’re doing in our lives,” said Deirdre Barrett, Harvard psychologist and author of “The Committee of Sleep” and “Trauma and Dreams.” “They’re just coming from such a different part of ourselves that they’re a very good supplement to our waking, rational thinking.” The dreaming brain Scientists know about as much about the dreaming brain as they do the waking brain — in other words, there’s still a lot to learn […]