Teaching about pain is one of the central problems of biology, medicine and psychology. Pain, one of the most common sensations, is characterized by a variety of manifestations. Many people know that the nature, severity, duration, location and other characteristics of pain can vary greatly. Pain is always unpleasant and the person is trying to get rid of this feeling. At the same time, it turns out that the pain is useful as it signals the occurrence of problems in the body. The ancient Greeks said that pain is "a watchdog of health".
The feeling of pain warns the body of the harmful effects of mechanical, chemical, electrical and other factors. Pain not only informs about the disadvantage, but also forces the body to take a number of measures to eliminate the causes of pain. This happens in a reflexive way. It is known that reflex is the body's response to various stimuli. In fact, when a person touches something hot or very cold, sharp, etc., they are instinctively instinctively removed from the effect of the harmful factor.
In the course of the evolution of the organic world, pain has become a signal of danger, an important biological factor that ensures the preservation of the life of the individual and thus of the species. Pain mobilises the body's defences to eliminate irritations and restore normal activity of organs and physiological systems.
Among all types of sensitivity, pain occupies a special place. While other types of sensitivity have a certain physical factor as sufficient stimulus (thermal, tactile, electric, etc.), pain signals states of organs that require special complex adaptive reactions. There is not a single universal stimulant for pain. As a general expression in the consciousness of a person, pain is caused by a variety of factors in different organs.
Pain is a subjective feeling that depends not only on the size of the stimulant it causes, but also on a person's mental, emotional response to pain.
1.1 Sensitivity to pain
The multifactorial nature of pain processes prevents researchers from achieving a single definition of pain at all. "Pain should be considered as an integrative function of the body that includes components such as consciousness, feelings, emotions, memory, motivation and behavioural responses.
Is an unpleasant feeling or suffering caused by irritation of specific nerve endings in damaged or already damaged tissues of the body. It seems that the biological meaning of pain is that it serves as a wake-up call and makes it necessary to reduce physical activity in the event of injury or illness, which facilitates the recovery process.
Pain is not only a signalling pain, but also a protective device. People who do not feel pain, which in rare cases can be a birth defect or a consequence of a disease of the nervous system, are unable to avoid the effects of the harmful factor in time and can become victims of accidents, although they constantly take precautions and try to protect themselves from burns, injuries, radiation exposure, etc. These people are easily identified during the examination: They usually have numerous scars on their skin caused by burns, wounds, etc.
However difficult it may be for a person who is not in pain, it is even more difficult for someone who is in pain for a long time. After the pain has fulfilled its protective function, it becomes the worst enemy of the body. It withdraws strength, pushes the psyche, disturbs the functions of different systems of the body. Reduces the motor activity of man, sleep, appetite, etc..
As you know, the feeling of pain in the human body is formed by the nervous system. The main parts of the nervous system are the brain, spinal cord, nerve trunks and their end devices (receptors), which convert the energy of external irritation into nerve impulses.
The brain and spinal cord are the central nervous system, and all other units of the nervous system are peripheral. In the brain, the hemispheres and brain stems are secreted. Hemispheres are represented by the white substance - nerve conductor and the grey substance - nerve cells. The grey substance is mainly located on the surface of the hemispheres and forms the cerebral cortex. It is also located in the depths of the hemispheres in the form of separate clusters of cell groups.
These are so-called subcortical nodes. Among the latter, visual hills (left and right) are of great importance for the formation of pain. They concentrate cells of all kinds of body sensitivity. In the brain stem, the accumulation of gray matter cells forms the nuclei of the craniocerebral nerves, from which various nerves begin to provide sensitive and motorized innervation of the head, face, mouth, throat and larynx.