Nervous Impulse

more commonly called "all or nothing".

The nerve impulse is the main mechanism for transmitting information in the nervous system of living organisms. It arises as a result of electrochemical excitation of nerve cells and is transmitted along nerve fibers. Initially, scientists for a long time could not understand how the transmission of a nerve impulse occurs, since no visible changes occur as it passes along the nerve.

With the development of microchemical methods, it was possible to show that in the process of transmitting a nerve impulse, the nerve spends more energy, consumes more oxygen and releases more carbon dioxide than at rest. This indicates that oxidative reactions are involved in the conduction of an impulse, in the restoration of the initial state after conduction, or in both of these processes.

However, when it was discovered that a nerve impulse was accompanied by certain electrical phenomena, many scientists mistakenly believed that the impulse itself represented an electrical current. But further research showed that the nerve impulse is not an electric current, but is an electrochemical disturbance in the nerve fiber.

The transmission of a nerve impulse is similar to the burning of a fuse, where the heat released during the combustion of one section of the cord lights up the next section, etc. In the nerve, the role of heat is played by electrical phenomena, which, having arisen in one area, stimulate the next.

The speed of nerve impulse transmission depends on many factors, including the diameter of the nerve fibers, myelination (the presence of a myelin sheath around the nerve fibers), the concentration of ions inside and outside the nerve fibers, temperature, etc. The speed of impulse transmission can reach up to 120 m/s in myelinated nerves, which makes possible the fast and efficient transmission of information in the nervous system.

Thus, a nerve impulse is a complex process of electrochemical excitation of nerve cells and transmission of signals along nerve fibers. Understanding the nature of the nerve impulse is an important step in understanding the functioning of the nervous system and developing new methods for treating nervous diseases.