SCP is one of the oldest, if not “ancient” electrophysiological indicators. As early as 1827, L. Nobile described the so-called “frog current”, which spread from the limbs to the head. In humans, the direction of such currents was worn by the opposite character actor . At this time, galvanometers and non-polarizable electrodes were used to record electrophysiological processes. Registration of bioelectric phenomena using galvanometers was accompanied by numerous artifacts that arose in connection with the drift of the device, human movements, changes in electrode potentials. Therefore, in electrophysiology we switched to the use of amplifiers with low-pass activity filters, which guaranteed a stable recording level. Such recording devices eliminated the slow-wave activity, and the main attention of electrophysiologists at that time switched to the study of activity in the EEG frequency range. Improving the quality of DC amplifiers and non-polarizable electrodes in 30-60 years. XX century the researchers again aroused great interest in the study of constant currents and voltages, then a period of disappointment and calm began, and finally, starting around the middle of the 80s. XX century a new stage in the history of studying the constant potentials of the brain. At that time, Western studies began to pay much attention to the slow components of evoked potentials, and in the domestic, besides this, to constant potentials of the millivolt range . In addition, there were also works devoted to the potential difference between the BBB and other potentials from a vascular origin .
The initial interest in constant potentials, their gradients and currents was associated with the ideas that dominated science in the 30-40s. XX century So, it was believed that the electric field is an essential part of the organization that ensures existence or is a manifestation of vital energy. According to the generally accepted hypothesis at that time, in particular, it was believed that the potential gradient existing in the fertilized egg promotes the normal development of the embryo by directing and orienting the body molecules in a certain way, especially in the early stages of development. These assumptions were based on experiments on the influence of weak electric fields on the direction of axon growth in cell culture, as well as on regeneration processes in amphibians. In a certain form, these ideas came to our time .
Similarly, it was believed that clusters of neurons in the nerve centers of the brain are also subject to the controlling influence of an organized electric field. In the widespread hypothesis, it was argued that the electric field of the brain has vertical and horizontal gradients, due to which the unity of action of the nerve center is maintained . This area of research at the present stage is largely associated with the work of W. Adie and his students.
One of the most striking researchers of constant potentials, which had a significant impact on subsequent generations of scientists, was Harold Burr. His works were published from 1916 to 1956, the last book, “A Sketch for Immortality,” was published in 1972. In his work, G. Burr studied the constant potentials of the brain, as well as other organs. He came to the conclusion that in a living organism there are electric fields, not only reflecting the activity of various organs and formations, but also ensuring their normal existence and functioning. In his opinion, electric fields are a reflection of the vital energy existing in the body. Therefore, these fields were called them L-fields (L – from the English life). In the works of G. Burr and his closest students (F. Northrop and L. Ravitz), changes in SCP were observed for various functional conditions of humans and animals (hypnosis, various stages of the ovulation cycle, hunger and satiety, etc.), as well as age dynamics SCP (when registering potentials between the arm and the head). In addition, in these studies it was found that a change in the functional state is associated with an asymmetric distribution of constant potentials in the body. In particular, when the functional state changed, the interdigital index changed (when registering constant potentials between the fingers of the same name in both hands). This was, in fact, one of the first examples of the relationship of a functional state with an electrophysiological indicator of functional asymmetry.
Rusinova historically approached the study of slow electrical activity from a position based on the notion of a dominant lesion in her works, using the hypothesis of a stationary excitation focus characterized by altered thresholds for the excitation of nerve cells. Therefore, he was close to the views of G. Boer and other researchers on the gradients of the electric field. In one of the works it was said: “A longitudinal, transverse and transcallosal gradient of constant potential (cortex) is regularly conserved from object to object.” Particular attention is paid scientists of this school of slow change of electrical potentials at different stages of development of a conditioned reflex, and nerve centers work modification via brain polarization constant yannym current .
At one time, the idea of modifying the work of nerve centers with the help of electric fields created due to the structural ordering of neurons in the brain was of great interest. In many works , the influence of an electric field created by the activity of nerve cells on neighboring neurons was assumed. From the fact that the oscillations of constant potential, impedance, impulse activity are isorhythmic , she concluded that “the genesis of super slow oscillations is induced by electric charge oscillations and the configuration of the intercellular electric matrix”, which can combine neural ensembles into a single system. A hypothesis was expressed about the participation of a constant potential in the control of the conformational state of protein molecules that fix the information . It was believed that the SCP cortex reflects the magnitude of the stationary excitation of the nerve center, and the constant potential can play the role of a factor involved in the formation of simple forms of temporary communication.
It is also necessary to mention the works of N.A. Aladzha Lova and her students , who approached the study of SCP from electroencephalographic positions, i.e. considered constant potentials as EEG waves, only very slow. According to V.A. Ilyukhina et al. , There is a relationship between the potential difference recorded between the tener of the hand and the vertex, and the functional energetic states of a person. suggested a connection between SCP and energy-deficient states of the body. In the works of these authors, slow waves are called omega potentials.