Dreams are the playground of the mind. Anything can happen when one is dreaming. The only limitation is that we only rarely realize the freedoms granted to us in our dreams while we have them. Lucid dreaming is the ability to know when one is dreaming, and be able to influence what will be dreamt. A normal dream is much like passively watching a movie take place in your skull. In a lucid dream, the dreamer is the writer, director, and star of the movie. Lucid dreams are exceptionally interesting.
Lucid dreaming is defined as dreaming when the dreamer knows that they are dreaming. The term was coined during the 1910Õs by Frederik van Eeden who used the word "lucid" in the sense of mental clarity (Green, 1968). Lucidity usually begins in the midst of a dream, when the dreamer realizes that the experience is not occurring in physical reality, but is a dream. Often this realization is triggered by the dreamer noticing some impossible or unlikely occurrence in the dream, such as meeting a person who is dead, or flying with or without wings. Sometimes people become lucid without noticing any particular clue in the dream; they just suddenly realize that they are in a dream. A minority of lucid dreams (about 10 percent) are the result of returning to REM sleep directly from an awakening with unbroken reflective consciousness (LaBerge, 1985). These types of lucid dreams occur most often during daytime napping. If the napper has been REM deprived from a previous night of little sleep their chances of having a REM period at sleep onset are increased. If the napper is able to continue his or her train of thought up to the point of sleep, a lucid dream may develop due to an immediate REM period.
The basic definition of lucid dreaming requires nothing more than the dreamer becoming aware that they are dreaming. However, the quality of lucidity varies greatly. When lucidity is at a high level, the dreamer is aware that everything experienced in the dream is occurring in their mind, that there is no real danger, and that they are asleep in bed and will awaken eventually. With low-level lucidity they may be aware to a certain extent that they are dreaming, perhaps enough to fly, or alter what they are doing, but not enough to realize that the people in the dream are just figments of their imagination. They are also unaware that they can suffer no physical damage while in the dream or that they are actually in bed. Lucidity and control in dreams are not the same thing. It is possible to be lucid and have little control over dream content, and conversely, to have a great deal of control without being explicitly aware that one is dreaming.
Lucid dreams usually happen during REM sleep. Working at Stanford University, Dr. Stephen LaBerge proved this by eliciting deliberate eye movement signals given by lucid dreamers during their REM sleep. LaBerge's subjects slept in the laboratory, while the standard measures of sleep physiology (brain waves, muscle tone and eye movements) were recorded. As soon as they became lucid in a dream, they moved their eyes in large sweeping motions left-right-left-right, as far as possible. This left an unmistakable marker on the physiological record of the eye movements. Analysis of the records showed that in every case, the eye movements marking the times when the subjects realized they were dreaming occurred in the middle of unambiguous REM sleep. LaBerge has done several experiments on lucid dreaming using the eye-movement signaling method, demonstrating interesting connections between dreamed actions and physiological responses.
It has been debated if lucid dreaming interferes with the function of Ò normalÓ dreaming. According to one way of thinking, lucid dreaming is normal dreaming. The brain and body are in the same physiological state of REM sleep during lucid dreaming as they are during most ordinary non-lucid dreaming. In dreams the mind creates experiences...