Why do dreams cause electrical impulses

The dreamer immerses himself in a new reality with all of his senses

The experiences in the lucid dream are as intense as if they were reality. This distinguishes the lucid state from the daydream, whose fantasy images appear paler than real sensory impressions, and from a movie that only passes us two-dimensionally on a piece of canvas. And also from a computer game that we only experience in a section of our field of vision. In a lucid dream, you immerse yourself in a self-generated reality with all your senses. When Richard Feynman turned around in the railroad car, the room seemed to continue behind his back. In another lucid dream he experimented with a thumbtack stuck in a door frame. When he ran his fingers over the frame, he could feel it. Lucid dreamers also feel hot and cold, dry and wet.

The British psychologist Hugh Callaway has vividly described the intensity of such experiences: “The quality of the dream changed in a way that is very difficult to convey to someone who has never had the experience. Immediately, clarity and vibrancy increased a hundredfold. The sea, the sky and the trees had never exuded such enchanting beauty; even the ordinary houses were filled with inner life and mystically beautiful. I've never felt so comfortable, so clear in my head, and so free. "

A strange hybrid of sleeping and waking

The new measurements confirm such reports. In lucid dreams, people can see too clearly because certain areas on the back of the head that contribute to the conscious perception of images are exceptionally active. Because the lucid state is a strange hybrid of sleeping and waking; it comes about through a special constellation of active and deactivated brain centers.

When the lucid dream sets in, the waves of electrical brain waves accelerate up to 40 oscillations per second. That is the frequency that these waves also have during the day. The waking consciousness breaks into sleep. And the frontal lobe, the prefrontal cortex, which is normally turned down at night, wakes up. This allows the dreamer to think critically and direct his attention. He gains a different feeling for himself than usual in dreams; While one otherwise blindly pursues goals and the knowledge of one's own identity at most flashes, the ego is almost continuously present in the lucid dream. It can analyze its own condition and suddenly realizes: My goodness, I'm dreaming!

Some of the finest accounts of lucid dreams ever come from Mary Arnold-Forster, a London writer who spent her long life from 1861 to 1951 exploring her nocturnal state of mind in depth. It tells of the intricate thoughts the mind is capable of in lucid dreams. As the daughter of the Victorian era, Arnold-Forster even tried to maintain decency in the lucid dream.

Float over the street in a flight dress

“Now I always see myself in my flight dress - a dress with dense, tight-fitting folds that fall at least a hand's breadth below the soles of my feet. When I was floating a little above the ground through busy streets, I thought that people must have noticed that my feet move differently than theirs. In Oxford Street, where there were crowds of people on the sidewalk, I was afraid that it would cause a nuisance, ”she wrote.

Lucid dreams almost always begin with the sleeper noticing a discrepancy. Hugh Callaway experienced the sea, the sky and the trees in an unprecedented beauty after he saw himself standing on the sidewalk in front of his house one morning and noticed that the paving stones were lying differently than usual. he realized the only possible explanation: it's a dream.

Usually we carelessly pass by the oddities in the dream. Therefore, one effective way to induce lucid dreams is to raise one's awareness of weirdness during the day. The training simply consists of asking yourself the question as often as possible during the day: “Am I awake or am I dreaming?” It is crucial not only to give the answer, but also to justify it. For example, you can check the current state of your own memory, whether you feel firmly connected to the earth or are flying, or whether a wall gives way when you lean against it. And what happens if you let your eyes wander for a moment? Does everything look like it did before, or did people appear out of nowhere, things disappeared?

The goal is to make the reality test so habitual that you run it automatically, literally while you sleep. If, after a few weeks of practice, such a nocturnal routine check turns out that your hand has six fingers or the person you are talking to is floating, the case is clear: you have awakened in a dream world.

You couldn't fly on your back

Amazingly, even tests that require some thought will do their job. Once I saw myself sitting on my back in a jet, and I was afraid. My physicist mind seemed to stir. It occurred to me that an airplane couldn't stay in the air for a moment because the flow was stalling at the wings. Now I knew that it was harmless because I was dreaming - and I enjoyed the wild flight.

The heroes in the Hollywood cult film “Inception”, on the other hand, have got used to handling special objects called “totems”. Leonardo DiCaprio, as Dominick Cobb, repeatedly sets a small spinning top in motion. If the toy falls over, Cobb is obviously awake; if it goes on and on, he knows he is dreaming.

Many lucid dreamers use these insights to direct the action. So you can fulfill all imaginable wishes in virtual reality. But we are not granted such freedom of design in every lucid dream. I myself often just admired the beauty of the dream images in amazement and excitement - but never even got the idea to change them.

If you stimulate the brain electrically, lucid dreams arise

In May 2014, the Frankfurt psychologist Ursula Voss caused a sensation with the news that lucid states can be specifically triggered by electrical stimulation of the brain during sleep. The frequency of the current was 40 oscillations per second; so it corresponded to the brain waves during lucid dreaming and in the waking state. And as if the convolutions of the frontal lobe had only been waiting for this impulse, the dreamers really fell into a lucid state. Their brains gave all appropriate electrical signals, and if you woke the sleepers after a few minutes, they reported a lucid dream.

If, on the other hand, Voss set a different frequency or switched off the device, the lucid dreams stayed away. There is no doubt that the 40-Hertz vibrations triggered the special state of consciousness. Without interrupting the dream, they activated precisely those regions of the cerebrum that are responsible for action control and conscious memory. This enabled the test subjects to gain control over their dreams.

For the first time it has been possible to lead people to the limit where waking reason is combined with the unlimited inventiveness of dreams. This success not only promises new training methods or more effective psychotherapies, but could also unleash unimagined creative powers in people. Will we still watch TV, go to the cinema or travel when we have the opportunity to create every longed-for experience at the push of a button in our sleep? Tinkerers are already thinking about having a usable lucid dream machine manufactured in series.

The author has published a book on the subject: Stefan Klein: Dreams. A journey into our inner reality. S. Fischer, Frankfurt am Main, 2014. 320 pages, 19.99 euros.

  • The art of lucid dream
  • The dreamer immerses himself in a new reality with all of his senses
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