7

Introduction

FIGURE 1.1 Te electromagnetic spectrum forms static feld (0 Hz) through extremely low-frequency felds

(ELF-EMF) high-frequency feld (HF-EMF) to light. Te typical sources are included. (Courtesy of JEIC, Tokyo.)

to understand because of the diferent types of electromagnetic phenomena that are involved in the con­

cept of bioelectromagnetism. Tus, it is an interdisciplinary study that examines the electric, magnetic

and electromagnetic phenomena produced by biological systems, and it also involves the measurement

and stimulation associated with biological tissues. Tis means that the concept of bioelectromagnetism

can be divided in diferent ways; here, it has been divided into two parts. Te frst one is the study of the

interaction between electromagnetic felds up to 300 GHz and biological systems. Te second one is the

research feld that measures electric and magnetic felds originated from bioelectric sources.

Looking back at the history of bioelectromagnetism, the basic research felds can be divided into the

following four academic categories: bioelectricity, electrobiology, biomagnetism and magnetobiology.

Bioelectricity is the study of the electrical phenomena generated in biological systems through the use

of electrophysiological techniques. Te electrical phenomena include properties inherent to the cells,

such as membrane potential, action potential and the propagation of the potentials. Bioelectricity has

also interest in the efects of biological systems by externally applied electricity. Here the word “efects”

of external electricity means how the cells in biological systems respond to the applied or exposed felds.

Te diference in electrical potential existing between the inside part of a cell and the extracellular

fuid surrounding it is called the membrane potential. It is a specialized function of the nervous sys­

tem is to propagate membrane potential changes within a cell and to transmit them to other cells. Te