How seasonal sleep reduction affects brain function. Answered by a psychologist

With the arrival of the fall and winter months, many people often experience a worsening of mood, decreased efficiency, increased fatigue and apathy, decreased concentration, lethargy or insomnia. And there are good reasons for that.

Candidate of Psychological Sciences, Associate Professor

The beginning of the autumn-winter season and the associated autumn moping, according to the All-Russian Center for Public Opinion Research, in one way or another affects about 42% of the adult population of Russia.

This is primarily due to the fact that at this time people start spending more time at work and at home, at their TV screens, at computers, with tablets and smartphones in their hands.

There is a natural change in the major brain and central nervous system neurotransmitters that regulate mood and natural circadian sleep/wake rhythms: serotonin, dopamine and melatonin.

Reduced natural light levels also lead to a significant reduction in levels of serotonin and melatonin, hormones that are closely related. This, in turn, is accompanied by symptoms of seasonal moping.

One of the main signs is a disruption of the circadian rhythm, the sleep/wake cycle, in which many people feel drowsy, and at night, on the contrary, cannot fall asleep for a long time or wake up early/frequently during the night.

At the same time, the human body is in dire need of adequate sleep to restore and maintain physical, mental, and emotional health, because sleep is the time when the cells of the entire body regenerate.

When a person goes to bed, his body rests, muscles relax, there is a decrease in the level of cortisol – the stress hormone, and the brain at this time continues to work.

On the quality of sleep depends on the health of the brain, which regulates the work of all other human organs, and thus the emotional and psychophysiological state of the person as a whole.

How the reduction of sleep affects the work of the brain

Sleep performs a number of essential and indispensable functions for a person.

First, during a night’s sleep, the central nervous system is cleansed of metabolites. In sleep, under the guidance of the brain in the body there is a “cleaning”, the processes of binding and neutralization of toxins are actively going on.

In 2012, foreign scientists discovered the glymphatic system – a system of microchannels in the brain, which opens during sleep and is responsible for the removal of toxins from the central nervous system.

During night rest, the brain performs a “scan” of the body – analyzing the state of the organs, as well as the elimination of detected malfunctions.

Secondly, during sleep, especially its fast phase, there is removal of unnecessary information accumulated during the day and emotional restructuring, manifested in a decrease in the excitability of foci of motivational arousal.

Thirdly, during sleep there is a transition of information from short-term memory to long-term memory. For this reason, it is much more effective to learn material before going to bed.

Thus, in sleep many autonomic functions are activated (respiration, blood circulation, digestion) and processes necessary for the normal functioning of the body during the day.

These processes can not be carried out when awake, so a person should follow biological rhythms and sleep at least seven to eight hours.

The main reason for seasonal sleep disturbance, besides the low amount of sunlight affecting serotonin/melatonin production, is the presence of constant information overload in modern man.

A person wakes up in the morning and immediately grabs the phone, reading news or messages from social networks, looks at the phone on the way to work and back, during work and before going to bed.

All this leads to a dramatic increase in the brain’s activating systems throughout the day, each of which has its own mediator. Meanwhile, these are important biologically active chemicals, through which the transmission of impulse between neurons is carried out.

Therefore, a full, regular sleep is essential for a person. This is a kind of prevention of cognitive changes associated with attention, memory, speech, perception.