Here are some other things you may have noticed about your dreams:

* Dreams tell a story. They are like a TV show, with scenes, characters and props.

* Dreams are egocentric. They almost always involve you.

* Dreams incorporate things that have happened to you recently. They can also incorporate deep wishes and fears.

* A noise in the environment is often worked in to a dream in some way, giving some credibility to the idea that dreams are simply the brain's response to random impulses.

* You usually cannot control a dream -- in fact, many dreams emphasize your lack of control by making it impossible to run or yell. (However, proponents of lucid dreaming try to help you gain control.)