For me it is usually more like needing to "wake up", so to speak, and realize things around me are actually real. It is quite common for me to suddenly find myself feeling and acting like something is only a dream, and there are times when I must stop everything for a few moments so I can collect my senses (sometimes even shaking my head a bit to awaken my intellect or whatever) before crashing the car (for example) because I had been in a daydream-like state rather than fully aware I was in a very real situation and *not* merely fly-dreaming.