As defined by Wikipedia a lucid dream is…
…any dream in which one is aware that one is dreaming.
The phenomenon had also been referred to by Greek philosopher Aristotle who had observed:
often when one is asleep, there is something in consciousness which declares that what then presents itself is but a dream.
One of the earliest references to personal experiences with lucid dreaming was by Marie-Jean-Léon, Marquis d'Hervey de Saint Denys. The person most widely acknowledged as having coined the term is Dutch psychiatrist and writer Frederik (Willem) van Eeden (1860–1932).
In a lucid dream, the dreamer has greater chances to exert some degree of control over their participation within the dream or be able to manipulate their imaginary experiences in the dream environment. Lucid dreams can be realistic and vivid. It is shown that there are higher amounts of beta-1 frequency band (13–19 Hz) experienced by lucid dreamers, hence there is an increased amount of activity in the parietal lobes making lucid dreaming a conscious process.
Skeptics of the phenomenon suggest that it is not a state of sleep, but of brief wakefulness. Others point out that there is no way to prove the truth of lucid dreaming other than to ask the dreamer. Lucid dreaming has been researched scientifically, with test subjects performing pre-determined physical responses while experiencing a lucid dream.
Is lucid dreaming haram?