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Bioelectromagnetism

measures bio-signals advanced with the developed equipment, bioelectromagnetism can ofer oppor­

tunities for developing therapeutic and diagnostic applications and promote understanding of the bio­

logical interactions of electromagnetic felds with living systems. Now, bioelectromagnetism is mainly

related to electricity, magnetism, bioelectricity (electrobiology), and biomagnetism (magnetobiology).

Bioelectricity as a division of bioelectromagnetism is a fundamental process of all living systems and is

the study of electrical phenomena generated in living systems. Te electrical phenomena include inher­

ent properties of the cells, such as membrane potential, action potential, and propagation of the poten­

tial. Biomagnetism deals with magnetic phenomena in all living systems, which can be observed at

diferent intensities and frequencies. For example, the so-called magnetophosphene is a visual sensation

elicited by exposing the head to a low-frequency magnetic feld. Te signal is generated in the retina.

Magnetic stimulation of the human brain and heart has been used for the purpose of both research and

clinical treatment. Using Superconductive QUantum Interference Devices (SQUID), the weak magnetic

felds from the brain, heart, and lung can be measured from outside the body.

Te long historical development of bioelectromagnetism reveals that today’s scientifc achievements

in engineering, biomedical engineering, biology, and medicine are shaped by solving the electromag­

netic phenomena in living systems. Many experimental and theoretical research studies in bioelectro­

magnetism emerged: (1) the relationship between electricity, magnetism, and life, (2) how electricity and

magnetism give action to living systems, (3) how living systems utilize electricity and magnetism, and

(4) how electromagnetic felds interact with living systems. In particular, it recently became important

to understand the interaction of electromagnetic felds with living systems not only for medical appli­

cations but also for protection from exposure to electromagnetic felds. Te discovery and important

issues in the history of bioelectromagnetism can be mainly divided into theory, instrumentation, and

measurement of interactions between the electromagnetic phenomena and living systems. Taking these

categories into consideration, the description of the history of natural science of electricity and magne­

tism is needed to look back on the development of bioelectromagnetism.

In this chapter, through overviewing the history of bioelectromagnetism, the argument could mainly

be divided into several topics, which got gradual success in bioelectromagnetism. Tis chapter as far as

possible included the historical development of Japanese research in bioelectromagnetism. From Sections

2.1–2.5 the important events in the history of bioelectromagnetism are chronologically structuralized. We

emphasize the description of history including the scientists who made physical, chemical, medical, and

biological discoveries. Section 2.6 deals with the historical debate about possible human health efects due

to exposure to electromagnetic felds: static, low-frequency, and radiofrequency (RF) feld. Tis debate

brings the fundamental approach for safety guidelines which will be presented in another chapter.

As major sources, we refer here three books: Bibliographical History of Electricity and Magnetism

(Mottelay, 1922), Electricity and Medicine: History of Teir Interaction (Rowbottom and Susskind, 1984),

and Galvani’s Spark: Te Story of the Nerve Impulse (McComas, 2011).

2.2 Discovery and First Step in Bioelectromagnetism

Te early history of bioelectromagnetism is not well documented. In 3000 BC, the Nile catfsh

(Malapterurus electricus) was written in an ancient Egyptian mural. Tis is the frst recorded document

on the electric fsh. Tales of Miletus (625–547 BC), the Greek scientist, also an astronomer, one of the

seven wise men of Greece, rubbed amber with cat fur, and recognized its power. He recorded frst about

the magnetic properties of ferric oxide, Fe3O4. Unfortunately, Tales lef no writings. All were transmit­

ted orally. Te word “amber” means “electron” in Greek. In 341 BC, Aristotle (384–322 BC), the Greek

philosopher, described about torpedo (electric fsh), which gives electric shocks to humans. Teophrastus

(372–287 BC), Aristotle’s pupil and his successor at the Lykeum at Athens, described the attractive power

of loadstone (magnet) and amber (Rowbottom and Susskind, 1984). Gaius Plinius Secundus (23–79 AD),

known as Pliny the Elder referred to the electric torpedo in his “Naturalis Historia (Natural History).”

The electric discharge of certain fishes generates a strong average of 350 V with high of 650 V

producing pain and shock in human. These fish include the Nile catfish, electric fish (torpedo),