Why do people go to sleep and who are sleepwalkers?
“Lunatics, ” as people used to call rooftops and cornices at night, are mentioned even in the Bible, in the Gospel of Matthew. This strange behavior of some of us in ancient times and today seems creepy and mysterious. However, over time, there have been fewer riddles, and if the mechanisms of the occurrence of sleepwalking are still not fully understood, something science already knows about them.
Violence in a dream
“Sleepwalking” is an outdated concept, since the influence of the moon on such manifestations of the human psyche is not considered a scientific fact. Another term is used: somnambulism, that is, “dreaming” (from the Latin words somnus - sleep and ambulare - to walk). There is a broader concept - “parasomnia”, combining a number of sleep disorders (obviously of a similar nature), which lead to unaccountable actions, not necessarily associated with walking. Here, for example, bruxism is a gnashing of teeth at night. The sleeping person suddenly suddenly strains the muscles of the jaw and larynx, and an unpleasant rattle is heard. The phenomenon has been known for a long time and has various popular interpretations - from indicating the presence of worms to a rudimentary instinct - they say, ancestors sharpened their teeth in a dream. Be that as it may, this is just one example of the fact that the body can live some kind of its own special life, while the owner is sleeping and does not suspect anything. The main thing is that this "life" does not go beyond a certain framework, and this sometimes happens.
Early in the morning of May 23, 1987, American Kenneth James Parks, the father of his five-month-old daughter, left the house, got into the car and went to the house of his wife's parents. In principle, he was going to visit relatives that day, with whom he was in excellent relations, but, of course, not in such an early age. Instead of gatherings at a party there was a tragedy. Parks burst into the house, beat his father-in-law, and stabbed his 42-year-old mother-in-law. Then the killer got into his car again, reached the police station and surrendered, claiming he had killed several people. Parks had no excuses, except for one: during the investigation, he stated that he did not remember at all what was done. The defense insisted that the murder was committed in an unconscious state, that is, it was a special case of somnambulism. Allegedly, Parks was in a serious psychological state due to failures in gambling, and this could cause such a severe sleep disturbance. The case was examined by a jury. It turned out that the young man didn’t really have any motives to crack down on his wife’s parents so cruelly - they always got along very well. It turned out that the electroencephalogram made during the investigation (at the time of sleep) shows a very strange state of the brain. As a result of the charge of killing the mother-in-law and attempted murder of her father-in-law, Parks was dropped. The decision was upheld by the US Supreme Court.
One can imagine how much skepticism many reacted to this verdict then, but jurisprudence is a serious matter, and it is unlikely that the court would have taken into account unfounded speculation. Cases of homicide in a state of somnambulia are rare, but not single, and there is evidence of them since the 17th century.
These are not dreams at all
But even if a person does no harm to anyone and does not drive (there are many such cases, for example, a person came to work in his pajamas), his behavior, say, while walking around the apartment at night, looks very strange. On the one hand, there is an absent look, an expressionless face, on the other - open eyes and actions, clearly subordinate to some plan. Often the "sleepwalkers" do not just wander around the house, but as if they are looking for something, open the doors of the cabinets, push the drawers. The simplest thing that can be assumed: these people have a dream, and they lose it without an account in reality. But this does not seem to be the case.
As you know, during a night's sleep a person goes through several cycles. About 25% of the time of each of these cycles, lasting 70-100 minutes, falls on the so-called phase of desynchronized sleep, also known as BDG-sleep. BDG (English abbreviation REM - rapid eyes movement) is a “rapid eye movement” that occurs behind closed eyelids. The brain is actively working in this phase, but the skeletal muscles are relaxed. It is at this time that we see dreams, and if a person is woken up in the phase of the BDG, he will most likely be able to tell what he dreamed about. In the series of "parasomnias" there is a sleep disorder, occurring just at this phase. Contrary to natural conditions, the sleeping muscles in the BDG phase may not be relaxed, but, on the contrary, may be active. A person moves his limbs, makes body movements, and most likely, these movements will be a reflection of what a person dreams. But this is not somnambulism. Studies show that it does not occur in the fifth, BDG phase of sleep, but in the third or fourth stages related to slow sleep, which makes up 75% of the cycle. These two stages are the exact opposite of the BDH phase, since they are a period of deep sleep, and brain activity during their course is at its lowest point. If you wake an ordinary person in the phase of deep sleep, he will recover for a long time until he understands where he is and what is happening to him. Exactly the same thing will happen with the awakened "sleepwalker."
By the way, among the parasomnia related to the phase of slow sleep, in addition to the mentioned somnambulia and bruxism, there are several more. Among them is food addiction. A person in a state of somnambulism sometimes, without waking up, can begin to actively eat something, and not necessarily edible, such as a pack of cigarettes. And for one of the disorders, even a very resonant term was coined: sexism. It is easy to guess its meaning: a person in a somnambulistic state begins to show sexual activity. Upon awakening, of course, he does not remember anything. Jokes? Not at all!
Too long and deep sleep
Ten years ago, in the English city of York, a trial was held on charges of a serious crime. 22-year-old bartender James Bilton was accused of raping a friend of the girl who spent the night at his house, but slept separately and did not give consent to sexual relations. The guy claimed that he did not remember anything and that he was extremely surprised by the accusations in the morning. The case was examined by a jury of seven women and five men, so it would seem that the defendant could not count on indulgence. However, the court took into account that Bilton had cases of somnambulism regularly occurred since the age of 13. In addition, this disorder was noted in members of his family. By decision of the jury, the rape charge was dropped.
The James Bilton case contains two important points regarding the nature of somnambulia. Firstly, it most often begins and occurs in childhood and adolescence. And if there are not so many adult “sleepwalkers”, then many have vague memories of night walks in childhood. Secondly, it is established that a genetic role plays a role in the occurrence of this sleep disorder. You can also add stress, the use of alcohol, drugs, certain medications, in general, everything that actively and negatively affects the psyche. On the other hand, the phenomenon of parasomnia itself is not fully understood, there are only a number of hypotheses.
One thing is almost certain: the awakening of a person in the phases of deep sleep is not very natural, and nevertheless, those suffering from sleep parasomnias have some kind of incentive for awakening. However, the attempt to wake up is unsuccessful: waking up, a person does not wake up, but goes to a special, unaccountable state.
A study published in 2012 in the scientific journal Neurology showed, in particular, the relationship between cases of somnambulism and other concomitant disorders with the duration of the stages of deep sleep. That is, the longer these stages, the consciousness, it turns out, it is more difficult to break out of Morpheus’s tight embrace, and strange phenomena occur. And the length of these stages can be affected by various stress factors, fatigue, chronic lack of sleep, or a variety of chemistry.
Two popular myths are associated with the "sleepwalkers", which are worth telling about. The first myth: a person cannot be woken up during the night walks. Allegedly, this is dangerous for himself and the one who wakes up (the “sleepwalker” may show aggression). In fact, all this is far from reality. It is difficult to wake a sleepwalker (like a person in general at the stages of deep sleep), but it is possible, and then he will think for a very long time how he got to where he was woken up. The second myth: that the "sleepwalkers" are not a goddamn brother and that in their night walks they are unable to injure themselves or do other harm to themselves (for example, fall or eat some muck). All this is also untrue, therefore help to a person moping about in a somnambulistic state will not hurt: it is best to try to unobtrusively take him back to bed.The article “The World Between Sleep and Awakening” was published in the journal Popular Mechanics (No. 5, May 2015).