How to manage sleep: direct effects on brain activity

    image
    A source


    Every Friday of the second full week of March, as part of the World Health Organization's project on sleep and health, is World Sleep Day. Today, Morpheus himself ordered to tune up the period when the body processes memories, twists dreams, “washes” the brain and does other useful things.


    There are people in the world who need only 4–5 hours of sleep, but very few of them. Most of the reduction of the night regime threatens destruction and death. Duration of sleep is of great importance, because it does not just take part of the day, but "eats" a third of life! If the duration cannot be reduced, is it possible to increase efficiency? It turns out, yes. There are ways to regulate the brain in a dream so as to increase its productivity without side effects.


    Bottomless pit of dreams


    image
    A source


    The visceral theory of sleep (PTS) states that we need sleep in order for the organs to get the necessary “computational power” for their own tuning. According to VTS, the brain practically does not suffer from sleep deprivation, but the internal organs begin to fail, because sleep is necessary for sequential debugging of all parts of our body. However, recent studies show that the brain also suffers from sleep disorders, like any other organs - lack of sleep not only impairs a person’s cognitive functions, but can also lead to irreversible damage and destruction of neurons.


    Once “sleeping at the weekend” you simply will not succeed - some studies involving people have shown that attention concentration and other cognitive functions cannot fully recover even after three days. In this regard, questions arise about how the theory of “sleep is not enough, but right” actually works and how to determine the measure of this correctness. On the other hand, if reducing sleep time leads to sharply negative consequences, other methods for correcting sleep should be explored.


    Electrical brain stimulation


    image
    A source


    Dr. Rudolph Llinas, one of the founders of neuroscience, in the report “Consciousness and coherent brain activity” proposed a model of the work of consciousness based on synchronization of neural activity. He suggested that the coherent electrical activity of part of the neural structure of the brain creates the necessary conditions for the emergence of visual images in the mind. This happens even if the sensory endings of the neurons do not work, for example, during dreams. It turned out that the 40 Hz oscillations can synchronize the impulses of neurons reacting to various aspects of the perceived image.


    German researcher Ursula Voss, her colleagues, neurophysiologists from Goethe University in Frankfurt and specialists from Harvard Medical School in Boston, investigated 27 volunteers . Scientists wanted to answer the question of what comes first: high frequency activity (about 40 Hz) in the gamma range leads to lucid dreaming or vice versa. They stimulated the brain of the subjects during sleep with weak electric current of different frequencies (from 2 to 100 Hz), that is, in all frequency ranges at which the brain itself operates.


    As it turned out, stimulation with a frequency of 40 Hz, at which the brain “works”, does not violate the usual signs of fast sleep, but leads to the fact that the brain itself begins to generate high-frequency waves of the gamma range (37–43 Hz). Scientists believe that in such conditions, neurons begin to emit synchronously electrical pulses with a given frequency.
    So, stimulation at frequencies of 40 Hz caused dreams in volunteers that they could control.


    [If the very fact of the passage of current through the brain frightens you, think about another phenomenon related to electrical stimulation during sleep. Electrotherapy is a method of treating a human CNS with a pulsed current of low frequency (1–150 Hz), of low power (up to 10 mA) and voltage up to 80 V during sleep. It improves blood circulation, increases the minute volume of respiration, stimulates redox processes, reduces pain sensitivity. In addition, it does not cause a decrease in memory and intelligence.]


    Benefit of Lucid Dreams


    Let's start with the main thing: not proven. In lucid dreaming (OS) you can “play”, the remnants of dreams can help in creative activity ... but they can not. However, this fact does not embarrass the creators of numerous startups, interfering with the work of sleep and do not take into account how the processes of alternating the phases of sleep are important for the brain.


    OSs are undocumented features, with unpredictable delayed effects. This is entertainment, which during long-term activity can seriously erode the barrier between sleep and reality. Nevertheless, there is a sense to deal with the OS at “short distances”. They can be used to treat phobias, aggressive conditions, depression and other problems. When you sleep and at this moment you realize that you are asleep, you can cope with any nightmare.


    Devices to call the OS


    image


    A dream in which you realize that you are sleeping is called lucid. From him to the OS at hand - there are many practices, they are all easily accessible and we will not consider them in detail. They require attention, concentration, motivation and commitment to achieve results. However, for those who are not ready to spend time independently achieving a result, there are a large number of ready-made devices in the world that facilitate entry into controlled sleep.


    image


    Startup Arenar launched a fundraising for the iBand + gadget , consisting of speakers for a cushion, a mobile application and a bandage, equipped with electrodes for encephalography and eye-directed LEDs. As a result, they collected 1289% of the requested amount, and they promise to start the delivery in September 2017.


    Why did you like the product so much? The electrodes pick up a specific moment when the fast sleep phase begins, after which the LEDs together with the loudspeakers emit weak audiovisual signals. The sleeper senses these signals as an anomaly in the dream, realizes his condition and takes control over what is happening (in theory). LEDs paired with EGG electrodes also work as a “smart alarm clock” that selects the most appropriate moment of the sleep cycle in order to awaken a person by imitating sunlight.


    image


    But not everything is as rosy as it looks in advertising. A similar product for many years developed in Ukraine. The Luciding gadget is made in the form of a thin bandage of hypoallergenic fabric, on the inside of which there are four sensor-electrodes: two sensors are in contact with the forehead, and two more are behind the ears. EEG Luciding determines the onset of REM sleep. At this very moment, the gadget sends a 30-second electric signal at a frequency of 40 Hz, which helps to realize the dream.


    image


    After developing numerous prototypes, the company did not come close to creating a stable device that guarantees immersion in lucid dreams. In world practice, this is not a precedent - a fake Luci device designed for managing dreams collected $ 363,000 on Kickstarter , but it never appeared to users.


    image


    Unlike electrical stimulation, light-based devices find more opportunities for use. IWinks Aurora has traditional sensors that monitor the electroencephalogram and electrooculogram (eye movements), as well as an accelerometer responsible for monitoring body movement. The gadget is able to track the phase of fast sleep and using the LED signal to let the user know that he is sleeping at the moment.


    Gadgets for lucid dreams continue to appear, they are in Russia.


    Reprogramming of circadian rhythms


    Impact on circadian rhythms (body clock) allows you to treat a number of disorders: from sleep disorders to behavioral, cognitive and metabolic abnormalities, usually associated with stress, change of work mode, exposure to light at night, as well as with neuropsychiatric conditions such as depression and autism.


    All living things on Earth experience the effects of a 24-hour cycle of light and darkness. Living organisms have adapted to the daily rotation of the Earth, developing biological rhythms, repeated after about 24 hours. These circadian rhythms are generated endogenously (inside the body).


    Biological clocks are “reset” due to protein phosphorylation in the brain — this process is triggered by light. In fact, light stimulates the synthesis of specific proteins, which play a key role in synchronizing the rhythm of a biological clock with the daily cycles of the environment.


    Studies at Stanford University have shown that flashing lights can "deceive" the body, causing it to "think" that it is in a different time zone. According to Mail Online, as a result of light therapy, the body clock can be adjusted by two hours a day.
    Thus, increasing the level of illumination helps to reduce drowsiness and partially level the side effects of seasonal affective disorder . Exposure to light will also help counter the negative effects of using a computer late at night.


    Setting rhythms as an idea for business


    image


    Based on research conducted at Flinders University (Australia), Thim developed a self-titled tracker that adapts the user's sleep pattern to a specific load for a week. On Kickstarter runs a campaign to raise funds to create a full-fledged device, made in the form of a ring for a finger.


    Thim is worn on the finger and wakes you up with gentle vibrations every three minutes for an hour. This process is called a light interruption of sleep and does not allow the user to wake up completely. According to the developers, in just one hour of interrupted sleep per day, a person for five nights in a row can adapt his sleep mode to any necessary workload.


    image


    Rise Science , a “bye-bye” startup from Chicago, provides personalized sleep coaching for colleges and professional athletes to help players get better sleep and perform at their best. The company creates an individual sleep schedule for each player and sends him automatic messages when it is time to go to bed.


    In 2013, they conducted extensive research on the effect of sleep on athletic performance. After taking into account the schedule of classes, age and genetic characteristics of the players, they determined the correct amount of sleep for 20 volunteers. Then they made a calendar and literally set for each player an individually optimal time for falling asleep / awakening, based on genetics. Some players needed seven and a half hours of sleep, and some seven hours and fifty minutes.


    After 8 weeks of the experiment, it was possible to establish that players who live according to their sleep schedules run faster on the field on the day of the game.


    4.20: polyphasic sleep


    image
    Popular sleep modes: in the diagrams, you see the shares of waking and sleeping periods


    At all times there were famous people who successfully used (and advised everyone) a divided dream. Sleep after work, during work, at lunch, double sleep per night, sleep for ten minutes every hour - many ways were invented. Fans of the method claim that a person’s refusal from slow sleep does not carry any negative consequences for the body, but at the same time saves a lot of time.


    In fact, if a person is faced with a lack of sleep, the slow phases will be eliminated, but in the future they will be compensated - the brain will sleep off when it allows (the consequences of this approach may not be very bright). Changes in the phase ratio of sleep are compensated for short periods, but with long-term experiments they can lead to a depletion of the nervous system.


    Scientific research on the effects of multiphase sleep on human health in the long term (a year or more) is not presented. The reason probably lies in the fact that it is extremely difficult to reconcile the schedules of polyphasic sleep with the mode of activity of other people of society. However, in extreme conditions, a nap of 10–20 minutes in the afternoon at regular intervals can help alleviate some of the symptoms of sleep deprivation.


    image


    The lack of scientific experiments does not stop startups and enthusiasts. They invented a NeuroOn mask for polyphasic sleep , which monitors brain waves, eyeball movements during sleep and changes in muscle tension. The mask awakens the person at the moment when he has completed the REM sleep stage. NeuroOn has built-in LEDs and motors for soft vibration, whereby it awakens the wearer.


    The Neuroon mask became available for pre-order in 2014, but the final version of the product appeared only after more than two years. Unlike other products of this class, it has an unusual feature for travelers. The application creates a personalized sleep adjustment program, during which the mask makes a series of light flashes, manipulating the production of melatonin in the body and reprogramming the circadian rhythm.


    Sound impact



    Even during sleep, the brain continues to record and process sounds. Extraneous noise can make you wake up, move in, turn over in bed, switch between sleep stages or even change your heart rate and blood pressure level - and you don’t remember any of this when you wake up. How sounds affect sleep depends on the stage of sleep, time of night, and even your individual perception.


    Based on these data, several devices were created, the performance of which was estimated experimentally. The following studies were conducted: they installed sensors on the forehead and around the ears, which monitored the state of a person’s sleep, measuring brain waves. When the sensors determined the onset of deep sleep, pink noise was turned on at the head of the bed, thanks to which it was possible to more effectively “transfer” the brain to the fast sleep stage.


    How sound affects our ability to sleep


    Scientific studies demonstrate that sounds, such as the roar of waves crashing against the shore, help people remember what they learned the day before. In the human brain, separate neuron networks are often activated together. The collective increase and decrease in the activity of neuron networks causes fluctuations that we see on the EEG. At different times, the brain oscillates at different frequencies. During sleep, the brain produces slow vibrations <1 Hz - hence the term “slow sleep” - and these vibrations are considered important for the consolidation of memories.


    Scientists from the University of Tübingen in Germany have suggested that memory can be improved through auditory stimulation, which causes slow fluctuations. The study was conducted on 11 volunteers who studied the association of words just before bedtime. Their knowledge of the words learned was tested first before bedtime, and then again the next day. While the subjects slept, they included short passages of pink noise . These "slices" of pink noise were confined to the "slow" vibrations of the brain of a sleeping person.


    As a result, we managed to find out that after exposure to pink noise in a dream, people could recall twice as many word associations as they did without stimulation. When the experiment was repeated with pink noise, which was not synchronized with the natural slow oscillations of the brain waves, no improvement was noted in the memory.


    White noise and silence



    In addition to pink, white noise also affects sleep. It blocks other variable noises and provides constant, soothing sounds to help you fall asleep. In fact, any sounds familiar to humans become analogous to white noise: it can be a TV, fan or air conditioner - they provide uneven frequency noise. Some people prefer other sounds: the sound of the waves, the chirping of crickets, the rustle of the wind.


    An alternative approach is associated with the effect of complete silence. Keep in mind that complete silence is individual and not suitable for everyone. Someone just physically cannot fall asleep without the distant noise of the street outside the window (reminiscent of white noise), and someone is forced to sleep in ear plugs.


    image


    Startup Muzo was introduced at Kickstarter in the summer of 2016. The developers planned to collect 100 thousand dollars for the production of the device, but attracted more than 430 thousand. And then on Indiegogo collected for five hundred percent above the required - almost two million dollars. This money went to the development of a device that is mounted on a window or any other flat surface and absorbs vibrations, and also creates sound waves that complement the background noise in such a way that it turns into silence. The device uses the same technology as the headphones with active noise cancellation. Deliveries should start this year.


    Light exposure


    image


    We are accustomed to thinking that sleep is the time of the absence of light. Total darkness, in which only normal existence is possible during sleep. However, light at a certain wavelength helps to sleep, improves mood, reduces depression, or makes us feel more active during work.


    Light is the main way to synchronize a biological clock with a sunny day. If we are not exposed to a sufficient amount of light of the correct spectrum for the amount of time the body needs, our biological clocks desynchronize with the sunny day and we may experience a breakdown.


    A person most often sleeps well when the circadian and homeostatic systems that affect the sleep-wake cycle are aligned. Another very well-known circadian rhythm is the melatonin production cycle. Melatonin is a hormone produced by the pineal gland at night (in dark conditions), signaling that it is time to sleep. Melatonin production time in the evening, occurring about 2 hours before natural sleep, is used as a circadian clock marker. Evening exposure to light slows the onset of melatonin production, delaying the onset of drowsiness. If a bright light wakes you up at night, night melatonin will return to a normal level only after 30–45 minutes in the dark.


    Seasonal Affective Disorder


    image


    Seasonal affective disorder (MAP) is a subtype of depression that occurs in the winter months and is carried by episodes in the fall and spring. The mechanisms for the onset of SAD are not yet known, some researchers have questioned the very existence of such a disorder, but the light can be effectively used as a treatment for some types of depression - and if it helps you, then why and why isn’t so important, is it?


    Late dawn during the winter months retards the circadian rhythms of those more susceptible to SAD. Another hypothesis is based on the assumption that the total amount of melatonin produced in individuals suffering from SAD is greater in the winter than in the summer months, which increases the amount of time that the body considers the night period of the day. In this case, it is recommended to use the light early in the morning or in the evening.


    Studies have demonstrated the effectiveness of treating symptoms of SBP even at low light levels (<500 lux per 470 nm — blue light). Increasing the radiation in the shortwave region allows to reduce the level of illumination, but at the same time get the same effect. It was found that exposure to bright white light (at least 3000 lux and above) for 1 hour in the morning for 2 weeks improves or strengthens night sleep for people with Alzheimer's disease.


    Studies have shown that continuous bright indirect white light (at least 1000 lux) in the daytime evened out circadian rhythms and eased the symptoms of depression.


    Light therapy at different lengths


    image
    24-hour demonstration room in the Research Center for Lighting at the Polytechnic Institute. Rensselara provides daytime electric lighting with cold light during the day and warm lighting in the evening.


    Researchers have proposed a 24-hour lighting scheme, which provides a high degree of stimulation of circadian rhythms during the daytime hours, low circadian stimulation in the evening hours and a special light at nighttime.


    image


    For example, a warm light (2700 K or lower), illuminating the cornea at a level of 1 lux, will allow safe movement in space at night, but does not suppress the hormone melatonin.


    In most studies to date, the disturbing effects of light have been associated with its ability to suppress melatonin, which, in turn, is considered one of the factors that increase the risk of developing certain types of cancer. Televisions, computers, even digital clocks - all of them are common sources of night blue light that violates the circadian rhythm. To work at night without disrupting the melatonin production rhythm, it is recommended to use red light (as from a fire). In addition, long-wave red light can improve the objective and subjective indicators of a healthy body activity.


    Green light causes a quick start to sleep - from 1 to 3 minutes. Blue and violet light delay sleep - the start of sleep takes from 16 to 19 minutes for blue and from 5 to 10 minutes for purple. People who used e-readers (30–50 lux) for 4 hours before going to bed, had trouble falling asleep. Similarly, people who slept with night lights of ~ 40 lux had a worse sleep. Even relatively low levels of night light can be detrimental.


    To maximize the results of light therapy, it is also important to accurately measure the light exposure during the 24-hour day, and not just to take an “instantaneous” measurement of light in a specific place and at a specific time. Light parameters are determined using a dosimeter. To specifically measure the amount of light that the human eye sees, use the device Daysimeter. The device accurately measures the basic characteristics of light: intensity, spectrum, duration.


    By the way, F.lux can be used for a computer , which automatically calibrates the monitor's color temperature depending on the time of day. This program reduces in the evening the proportion of blue in the color spectrum of the monitor.


    Conclusion


    The world of dreams is huge, I want to dive into it again and again, so that next time we will be able to touch on other states that we have not talked about today because of their borderness. For example, sleep deprivation is an extreme degree of exposure, which at the same time can produce a positive effect.


    In addition to the methods described, there is also an obvious tactile way to awaken the sleeping beauty. However, if the prince were a somnologist, he probably would have led his finger across the princess’s palm - in some cases this is one of the safest ways to awaken a person without stress.


    In the meantime, good night and sweet dreams.



    Also popular now: