What is lucid dreaming?

A lucid dream is one in which you know you are dreaming while it is happening. Control over the dream is a common consequence, but it is not the definition. Awareness is.

How it was verified

The obvious objection to lucid dreaming is that it is unfalsifiable self-report. That objection was answered in 1980, and the design is lovely.

During REM the body is paralysed, except the eyes. So LaBerge and colleagues asked trained lucid dreamers to signal, once lucid, with a pre-agreed sequence of deliberate eye movements. The signals appeared on the recording, during verified REM sleep, exactly as agreed.

That converted lucid dreaming from a claim into a measurable state.

What it is like

Reports vary enormously. Some describe full waking-level clarity; others a partial awareness that slips away. Control varies too, from changing one small detail to reshaping the environment.

The most common first reaction, by a distance, is to try to fly.

What it is not

• Not something everyone can do easily. Frequency varies a great deal between people.
• Not dangerous in itself, though chasing it badly costs sleep. See the safety guide.
• Not a route to information you do not have. A dream figure that tells you something you did not know is a dream figure your own mind wrote.