Neuroscientists are solving the mystery of insight -- the lightening bolt that delivers a perfect answer to your brain. Talk, mental focus and caffeine, it turns out, can suppress sudden breakthroughs. To invite insight into your mind, immerse yourself in the problem until you reach an impasse, then take a walk or a warm shower. "You've got to know when to step back," says one insight researcher. "If you're in an environment that forces you to produce and produce ... then you're not going to have any insights."