What is the circadian rhythm? Circadian rhythms and their disturbances

Almost all vital processes in nature go through a cycle. The simplest example of a cycle is the change of seasons. Every year, all living things go through four seasons: spring, summer, autumn and winter. Another example is the cycle of the complete rotation of our planet around the sun. One such rotation lasts a year. Or the complete rotation of the Earth around its axis, forming a day.

In our body, certain cycles also occur. Why does the human body have a need for sleep? Or what facilitates his awakening? What is the circadian rhythm? The human body is subject to a 24-hour cycle. The most important thing in this cycle is the change of sleep and wakefulness. This process is automatically regulated by the brain.

The concept of circadian rhythm

Circadian rhythms are a change in the intensity of biological processes occurring in the human body throughout the day. In other words, these are biological clock inside the body. Shoot down their rhythm can not, because it is fraught with various diseases of the psyche and vital organs.

Circadian rhythms normally create a circadian balance. The state when a person has a perfect state of health is called a circadian balance.

With a circadian balance, a person feels physically healthy, has a great appetite, a great mood, his body is rested and full of energy. Man is in his rhythm. But when the circadian balance is absent, the circadian rhythm is broken, then this leaves its imprint on the health of the body.

Occurrence of circadian rhythms

Everyone probably noticed for himself that he feels more efficient, energetic and full of vitality and energy at one time of the day and more exhausted, sluggish and sleepy - in others. This is due precisely to biological rhythms. For the work of the biological clock in the human body responsible for about 20 thousand neurons in the hypothalamus. Till now it is precisely not known, how these hours work. However, scientists are sure that for normal functioning of the body their work should be clear and well-coordinated, the circadian rhythm of the heart should always be normal.

On average, a person's mental activity has two peaks: 9:00 am and 9:00 pm. The physical strength of its peak reaches 11:00 in the morning and 19:00 in the evening.

The "sleep-wake" cycle

The constant change of day and night is a cycle from which the state of the human body, its circadian rhythm, directly depends. The cycle of changing night and day, responsible for the process of changing sleep and wakefulness. It is from the cycle "sleep - wakefulness" that the flow of many processes in the body, its normal functioning and work capacity depends.

Insufficient amount of sleep can cause a decrease in concentration, disability. In the absence of a full healthy sleep, intellectual functions deteriorate, metabolic processes in the body are disrupted. This is not all that is fraught with an abnormal circadian rhythm of sleep for the body. Also it is fraught with early brain aging, mental disorders and even schizophrenia.

The influence of daylight on circadian rhythms

When the sun goes beyond the horizon, the level of illumination falls. The human visual system sends signals to the brain. The development of a hormone such as melatonin is stimulated. It helps reduce human activity. Melatonin relaxes a person, makes you feel sleepy.

Conversely, when the sun appears on the horizon, a signal is sent to the human brain to increase the illumination. The production of melatonin goes to decrease. As a consequence, the activity of the human body rises.

In the regulation of the "sleep-wake" cycle, other stimuli also participate. For example, taking a shower or a bath, a familiar alarm clock, going to the bedroom, taking a horizontal position and any other habits.

Sunrises and sunsets

Scientists believe that it is the early ascent with dawn and retirement to sleep after the sun has left the horizon to make the work of biological clocks clear and well-coordinated.

It is for this reason that late dawn and early sunset in winter often leads to people feeling sleepy, sluggish and inhibited. This is a normal reaction of the body to daylight. Human biological clock can not tune in to normal work. Diurnal circadian rhythms fail, and various health problems arise.

The same decline in mood, a decrease in activity and a sense of impotence is experienced by people who live in the conditions of a polar night or when the weather is rainy for a very long time.

Chronotypes of man

Human circadian rhythms are still being investigated. Scientists suggested that there are three main chronotypes of the human body.

The first chronotypes include "larks" - people of the morning type. They wake up early, with the rising of the sun. The morning and the first half of the day the peak of their vigor, capacity for work and cheerfulness falls. In the evening, "larks" are drowsy, they go to bed early.

The second chronotype includes people of the evening type. They are called "owls". The "owls" behave in the opposite way to "larks". They go to bed very late and can not stand the morning awakenings. In the morning, the "owls" are drowsy, sluggish, working capacity is extremely low.

Morning inhibition of "owls" can be accompanied by a headache. Their efficiency rises only in the afternoon, often even after six in the evening. There are times when the peak of the "owl" efficiency drops out at night.

The third chronotype is people with fluctuations in the intensity of physiological possibilities throughout the day. They are called "pigeons" or, in other words, arrhythmics. Such people fall from one extreme to the other. They can equally effectively work both in the daytime and in the evening.

"Larks", "owls" or "pigeons" are people born, or do they become such? Answers to this question have not yet been found. However, many studies have been carried out, proving the existence of the relationship between the chronotype and the genus of human activity. For example: employees in most cases are "larks". People who work mentally are "owls." And the people of manual labor are "doves." That is, it turns out that a person is in power to adjust his biological clock, adapt to his rhythm of life. The main thing is not to hurt yourself.

Causes of circadian rhythm failure

Violation of circadian rhythms can occur for various reasons. The most basic and common causes of the failure of the biological clock:

• Work shifts.
• Pregnancy.
• Long trip, flight.
• Drug use.
• Various changes in the habitual way of life.
• Crossing other time zones.
• Owl syndrome. People with this chronotype prefer to go to bed very late. For this reason, they have difficulty with waking up in the morning.
• Syndrome of the lark. This chronotype is characterized by an early awakening. These people have difficulties when there is a need to work in the evening.
• When moving to summer or winter time. At many people in this period there is a decrease in working capacity, increase of irritability, impotence, apathy. And the translation of the arrows for winter time is easier than for summer.
• Fans of spending the night at the computer are also at risk of a circadian rhythm failure.
• Night work is very stressful for the body. At first it may not be felt, but fatigue accumulates every day, sleep deteriorates, work capacity decreases, apathy arises, which can be replaced by depression.
• Unforeseen situations, when day and night are interchanged.
• Young mothers often suffer from the fact that her circadian rhythms do not coincide with the rhythms of the child. Often children have a basic sleep during the day, and at night they sleep in small pieces of time. These children are said to have mixed up day and night. Mom in this case, of course, can not get enough sleep. Here there is a serious disruption of the circadian rhythm of the mother.

Regulation of circadian rhythms

A person should be able to adjust to any schedule, because life can provide many surprises that can be displayed extremely negatively on the work of biological clocks. Here are some tips that can help support circadian rhythms of a person:

• If a person is to fly, then from the east to the west it is better to choose the morning flight, and from the west to the east - on the contrary, the evening one. In this case, before flying westward for five days, one should try to retire to sleep a couple of hours later. In the east, on the contrary - a couple of hours earlier.
• Similarly, when you go to bed earlier or later, you can prepare for the translation of the hands of the watch for summer or winter time.
• It is necessary to try to go to bed not later than 23:00 - this is provided that the dream will last 7-8 hours. Otherwise, lie down earlier.
• In the case of shift work or some other circumstances, a person should receive his portion of sleep in the other half of the day or, in extreme cases, the next day.
• Do not delay sleep for the weekend. For 4-5 days the body can become so tired that it will not be enough sleep at the weekend. Or else something else may happen - there may be a deceptive opinion that there is no fatigue, and the body will suffer from insomnia. You can not bring the body to extremes, to test it for strength. The consequences can be very serious.

Treatment of circadian rhythm failure

Disorders of the circadian rhythm are treated after the diagnosis. The goal of the treatment is the return of the human body to the normal mode of operation, the restoration of the work of its biological clock. The main and most common method of treating circadian rhythm disorder is treatment with bright light or chronotherapy. Therapy with bright light is used to restore the normal functioning of the human body, to adjust the work of its internal biological clock. This technique gives significant results to people who have disrupted circadian rhythms of sleep.