A History of Sleep

The history of sleep and dreaming goes back to the BC era, when ancient Greeks and Egyptians were the leading technological force.

The Egyptians analyzed the meaning behind dreams and they analyzed dream symbols, searching for prophecies from the gods. They believed in three bodies: Shat (the corpse body), Ka (the living physical body) and Ba (the soul).

Ba was often represented in hieroglyphics as a human-headed bird floating above the sleeping body or corpse. According to one expert “...the Ba is the person but in another form. The Ba could be defined as an individual in an out-of-body state.” Was the Ba actually the lucid dreaming consciousness?

As with many Egyptian concepts, the Greeks soon wove this idea into their own culture. Superstition aside, the Greek philosopher Aristotle actually came up with the first scientific theory of sleep in 350 BC when he wrote: “a person awakes from sleep when digestion is complete”.

Actually, this is not true at all. But Aristotle deserves kudos for trying. The rest of the scientific community would ignore the science of sleep for another 2,000 years... And sleep and dreaming would become one of the most under-researched areas of human behavior.

Circadian Rhythms

In 1729, a French geophysicist identified biological rhythms by conducting a now-classic Circadian experiment.

Intrigued by the daily opening and closing of the leaves of a heliotrope plant, the frivolously named Jean-Jacques d'Ortous de Mairan decided to test whether this biological behavior was simply a response to the sun.

To do so, he confined a plant to the dark - yet the daily rhythmic motions of the heliotrope's leaves persisted even in the absence of sunlight. de Mairan had discovered Circadian Rhythms in plants, thought to originate from an endogenous clock.

Similarly, the human Circadian Rhythm is a 24-hour cycle driven by our biochemical, physiological, and behavioral processes.

For example, we enter our deepest sleep around 2am, and we have the lowest body temperature around 4.30am. Our greatest level of alertness occurs around 10am and we have the best co-ordination around 2.30pm.

This biological clock evolves to match your daily habits, and can even resynchronize itself when you cross multiple time zones in a matter of hours.

Sigmund Freud

The history of sleep and dreaming was changed forever when, in 1900, the infamous psychoanalyst Sigmund Freud published his controversial book, The Interpretation of Dreams.

Whether we love or hate Sigmund Freud, we have to admit that he revolutionized the way we think about ourselves. Much of this revolution can be traced to his seminal work, which outlined his theory of unconscious forces in the context of dream analysis.

Introducing the id, the superego, and their problem child, the ego, Sigmund Freud advanced scientific understanding of the mind immeasurably by exposing motivations normally invisible to our consciousness. While there's no question that his own biases and neuroses influenced his observations, the details are less important than the paradigm shift as a whole.

After Freud, our interior lives became richer and vastly more mysterious. He revealed that our minds are full of hidden memories and desires. He also believed in a meaning behind dreams - but rather than foretelling the future, they held psychological insights.

Soon after, some important advances in technology kick-started a revolution in sleep research. The history of sleep was being remodeled. Scientists all over Europe began documenting the physiology of sleep, measuring brainwaves with the EEG machine, and linking Rapid Eye Movement (REM) patterns to stages of dreaming.

Who Discovered Lucid Dreaming?

We can thank the eighth century Tibetan Buddhists for being the first to formally tutor the ability to lucid dream. They learned how to control dreams with Dream Yoga, using a technique that is now described as Wake Induced Lucid Dreams (WILD) in which you maintain full consciousness while slipping directly into the dream state.

In the Western world, the term "lucid dreaming" was first identified by Marquis d'Hervey de Saint-Denys in 1867 in his book, Les Rêves et les Moyens de les Diriger; Observations Pratiques - which translates as Dreams and the Ways to Direct Them: Practical Observations.

However the honor is usually credited to the Dutch psychiatrist, Frederik van Eeden. In his (much later) 1913 book, A Study of Dreams, he wrote:

"The seventh type of dreams, which I call lucid dreams, seems to me the most interesting and worthy of the most careful observation and study. Of this type I experienced and wrote down 352 cases in the period between January 20, 1898, and December 26, 1912.

In these lucid dreams the reintegration of the psychic functions is so complete that the sleeper remembers day-life and his own condition, reaches a state of perfect awareness, and is able to direct his attention, and to attempt different acts of free volition. Yet the sleep, as I am able confidently to state, is undisturbed, deep and refreshing. I obtained my first glimpse of this lucidity during sleep in June, 1897, in the following way. I dreamt that I was floating through a landscape with bare trees, knowing that it was April, and I remarked that the perspective of the branches and twigs changed quite naturally. Then I made the reflection, during sleep, that my fancy would never be able to invent or to make an image as intricate as the perspective movement of little twigs seen in floating by."

Lucid dreaming was later scientifically classified in the 1960s by Celia Green. She realized it was a separate state of consciousness and identified the scientific potential. Green was also the first to make the connection with REM sleep and false awakenings.

However, it was not until 1975 that lucid dreaming was scientifically proven in the laboratory. Lucid dreamer Alan Worsley at the University of Hull in England managed to signal to researcher Keith Hearne in the outside world. Upon gaining lucidity, he would indicate his consciousness and free will within the dreamstate with a pre-determined set of eye movements.

However, the Hearne's research went under the radar of mainstream science journals. So it was Stephen LaBerge in 1978 who famously performed this experiment and published data on the first scientifically-verified signal from a dreamer's mind to the outside world. LaBerge continues to be a leading force in lucid dream research as the founder of The Lucidity Institute and author of Exploring the World of Lucid Dreaming.

Recent Lucidity Studies

Scientists continue to learn more about lucid dreaming, whether it's measuring electronic activity in the brain or discovering potential new psychological applications.

In 2009, a German study conducted at the Neurological Laboratory in Frankfurt revealed significantly increased brain activity during lucid dreams. An EEG machine recorded frequencies in the 40 Hz (or GAMMA) range in lucid dreamers enjoying a bit of conscious REM. This is far higher than the normal dream state (THETA range, or 4-7 Hz).

The researchers also saw heightened activity in the frontal and frontolateral areas of the brain which are the seat of linguistic thought as well as other higher mental functions linked to self-awareness. It supports the theory that lucid dreaming is a unique state of consciousness separate from any other mental state.

And that is our rapid overview of the history of sleep and dreaming... Read on to continue learning about the science of sleep and dream analysis.