Introduction
The electrical properties and processes exhibited by biological tissue are of interest because of the insights that knowledge of them may provide concerning the way the body regulates its myriad processes, and because they may help explain the effects produced by applied electromagnetic energy. It is perhaps teleological to suggest that some electrical properties of tissue must have physiological significance simply because they are there. On the other hand, nature does not frequently endow living things with useless characteristics and it is especially important to explore those electrical properties that do not readily fit into present orthodox concepts.
The following brief discussion of the electrical characteristics of tissue provides a framework for understanding the studies that are described in later chapters. For a more comprehensive treatment, the reader should consult the original literature.