Dreaming LifeDreaming Life

Do people really have lucid dreams?

How do we know that people really have lucid dreams? Well, for one thing, many people say they've had them. But people say they have predicted the future, moved objects with their minds and been abducted by aliens. That doesn't mean that these things really happened. Suppose you've never had a lucid dream. If someone told you that they were aware that they were dreaming as they dreamed, you might not believe them.

According to science, saying that you've experienced something isn't proof that it actually has happened. A scientific way of proving that something really happens is to observe it happening in a controlled environment (a laboratory) and to record your observations.

In fact, scientists have observed lucid dreaming in the laboratory. Researchers took advantage of the fact that during the REM (rapid eye movement) stage of sleep, the stage in which we are most likely to dream, people can move their eyes. Beginning in the 1970s, scientists performed experiments in which they asked people who claimed to have lucid dreams to move their eyes in their dreams. They used polygraphs to measure the sleepers' eye movements. Almost all of the time, the polygraph records of eye movements matched the eye movements in the dreams. Other experiments have shown that actions in lucid dreams match real small muscle movements in the body of the sleeper. For example, if a lucid dreamer attempted to signal to an observer by writing something while in a dream, the observer would detect real corresponding movements in the hand muscles.

Why do some, but not all, people have lucid dreams?

Some neuroscientists think that lucid dreaming may have something to do with the dorsolateral prefontal cortex, which is part of the prefrontal cortex, the area of the brain that lies just below your forehead. The dorsolateral prefrontal cortex is involved with logical reasoning, integrating sensory information into short-term memory and with developing long-term memory.

In most people, the dorsolateral prefrontal cortex shuts down during REM sleep. This may be why people usually don't recognize that aspects of a dream are unreal or illogical, and why they often don't remember what they've dreamt once they awaken. It is possible that with lucid dreamers, the dorsolateral prefrontal cortex still functions while they are dreaming. The ability to recognize that you are dreaming may be a function of the dorsolateral prefrontal cortex.

When does lucid dreaming occur?

Dreaming usually occurs during REM sleep. There are two phases of REM sleep. One is called "phasic" and the other is called "tonic." During the phasic stage, irregular, short-lived activities, such as rapid eye movement and muscle twitching, occur. During the tonic stage, these activities temporarily subside.

Research shows that lucid dreaming occurs during the phasic stage of REM sleep. This stage seems to be the only stage of sleep where there is enough neural activity for you to become lucid.

Recent studies seem to show that during a lucid dream, some areas of the dreamer's brain are asleep while other areas are awake.