Where do dreams come from? What are they needed for? Professor Michel Jouvet, the discoverer of the REM sleep phase, answers.
Psychologies: Dreams appear during paradoxical sleep. What is it and how did you manage to discover the existence of this phase?
Michel Jouvet: REM sleep was discovered by our laboratory in 1959. Studying the formation of conditioned reflexes in cats, we unexpectedly recorded an amazing phenomenon that has not been described anywhere before. The sleeping animal showed rapid eye movements, intense brain activity, almost like during wakefulness, while the muscles were completely relaxed. This discovery turned all our ideas about dreams upside down.
Previously, it was believed that a dream is a series of short images that a person sees immediately before waking up. The state of the organism that we have discovered is not classical sleep and wakefulness, but a special, third state. We called it “paradoxical sleep” because it paradoxically combines complete relaxation of the muscles of the body and intense brain activity; it is active wakefulness directed inwards.
How many times a night does a person dream?
Four five. The duration of the first dreams is no more than 18-20 minutes, the last two “sessions” are longer, 25-30 minutes each. We usually remember the most recent dream, which ends with our awakening. It can be long or consist of four or five short episodes – and then it seems to us that we have been dreaming all night.
There are special dreams when the sleeper realizes that the action is not happening in reality
In total, all our nightly dreams last about 90 minutes. Their duration depends on age. In newborns, dreams make up 60% of their total sleep time, while in adults it is only 20%. This is why some scientists argue that sleep plays an important role in brain maturation.
You also discovered that there are two types of memory involved in dreaming…
I came to this conclusion by analyzing my own dreams – 6600, by the way! It was already known that dreams reflect the events of the past day, the experiences of the last week. But here you go, say, to the Amazon.
In the first week of your trip, your dreams will take place in your home “settings”, and their hero may well be an Indian who is located in your apartment. This example shows that not only short-term memory for upcoming events, but also long-term memory is involved in the creation of our dreams.
Why do some people not remember their dreams?
There are twenty percent of us among us. A person does not remember his dreams in two cases. The first is that if he woke up a few minutes after the end of the dream, during this time it disappears from memory. Another explanation is provided by psychoanalysis: a person wakes up, and his “I” – one of the main structures of personality – severely censors the images that “surfaced” from the unconscious. And everything is forgotten.
What is a dream made of?
For 40% – from the impressions of the day, and the rest – from the scenes associated with our fears, anxieties, worries. There are special dreams during which the sleeper realizes that the action is not happening in reality; there are – why not? – and prophetic dreams. I recently studied the dreams of two Africans. They have been in France for a long time, but every night they dream of their native Africa. The theme of dreams is far from exhausted by science, and each new study only confirms this.
After 40 years of research, can you answer the question why a person needs dreams?
Disappointing – no! It’s still a mystery. Neuroscientists don’t know what dreams are for, just as they don’t know exactly what consciousness is. For a long time it was believed that dreams are needed to fill the storerooms of our memory. Then they found that in the absence of a phase of paradoxical sleep and dreams, a person does not experience problems with either memory or thinking.
Dreams facilitate some learning processes and are directly related to our future.
English biophysicist Francis Crick put forward the opposite hypothesis: dreams help to forget! That is, the brain, like a supercomputer, uses dreams to erase insignificant memories. But in this case, a person who does not see dreams would have serious memory impairment. And this is not so. In theory, there are many white spots in general. For example, during the phase of REM sleep, our body consumes more oxygen than during wakefulness. And no one knows why!
You hypothesized that dreams keep our brains running.
I will say more: tomorrow is born in dreams, they prepare it. Their action can be compared with the method of mental visualization: for example, on the eve of the competition, a skier mentally runs the entire track with his eyes closed. If we measure the activity of his brain with the help of instruments, we will get the same data as if he was already on the track!
During the phase of paradoxical sleep, the same brain processes take place as in a waking person. And during the day, our brain quickly activates that part of the neurons that was involved during night dreams. Thus, dreams facilitate some learning processes and are directly related to our future. You can paraphrase the aphorism: I dream, therefore, the future exists!
About expert
Michel Jouvet – neurophysiologist and neurologist, one of the three “founding fathers” of modern somnology (sleep science), member of the National Academy of Sciences of France, directs research on the nature of sleep and dreams at the French National Institute of Health and Medical Research.