Bioelectric potentials

Electrical signals are used extensively within the human body to transfer information from one point to another. The signals travel through the nervous system and muscle fibers in what are known as excitable cells. The biopotentials are produced as a result of interactions between electrical and chemical activities. Electrically, a cell exhibits an ionic voltage, a resting potential, across its membrane. When the cell is appropriately stimulated, the membrane´s voltage changes and an action potential occurs. These action potentials propagate from one cell to the next, and information is transmitted through the body. The signals can be viewed as digital pulses because the action potentials are either “on” or “off”. Furthermore, the information is digitally encoded by the body´s ability to vary the frequency at which the action potentials occur. As a result, the overall communication system is a digital frequency modulated procedure