Bioelectric sources muscles

Bioelectric sources are endogenous sources found in the body. At a short distance the signals may be dominated by the nervous parts of the organ, at larger distance by the muscle mass under nervous control. The signals are generated by the electrical activity of the cell membranes. 

In living tissue, important communication control is implemented by hormones and nerves. Hormones are slow broadcasting information carriers nerves are quick prewired point-to-point information carriers. Some cells are not excitable, such as adipose, connective tissue, and blood. They are passive, not under nerve control, and only weakly polarized. However, nerve, muscle, and gland cells are polarized and excitable within a 1/1000 s, such cells may react on trigger signals. The excitation of a cell is accompanied by an action potential. The action potential is the basic bioelectric event and signal source in the body. 

Parallel with the discovery of new sources of electricity, the detection of small bioelectric currents became possible. Soon after 0rsted s discovery in 1820, the first galvanometers appeared. The problem was twofold to increase sensitivity and to make the new sources follow the rapid changes of muscle and nerve currents. 

---