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Bioelectromagnetism

wave became more popular in the USA and Germany. It returned to the times when d’Arsonval used the

induction method by high-frequency electric current. Te medical and military uses of radiowaves and

microwaves began rapidly in the 1920s afer these technical developments.

From 1930 to 1932, Takashi Minoshima (1895–1990), professor at Hokkaido Imperial University,

Sapporo, studied photochemistry at the University of Leipzig, Germany. During this time, Minoshima

visited the laboratory of professor Sieminsky, an electrophysiologist, at the University of Vienna, Austria.

Minoshima saw experiments in which the frog’s belly and back were placed on electrodes, separated by

air, and the samples were irradiated with short waves, which caused the frog’s spinal refexes to disap­

pear. When the radiation stopped, the refexes returned to normal. Minoshima was strongly impressed

with the action of short wave stimulations. Afer returning to Japan, he formed a research group. He

and his co-workers conducted basic research on cancer treatment and disinfection, and on the efects of

ultrashort wave and on the physiological efects in animals. In 1940, he organized the Ultrashort-Wave

Laboratory, and in 1943 the Research Institute of Ultrashort-Wave was established (HUSCAP, 1980).

Tere, electrophysiological studies were conducted, including studies on blood and biological tissue

conductivity, cervical sinus nerve activity, and oil-water nerve models. Tis institute has been reorga­

nized two times, into the now Research Institute for Electronic Science passing through the Research

Institute of Applied Electricity (RIAE). Since the 1970s, research on the biological efects of electromag­

netic felds has been carried out under the leadership of professors Goro Matsumoto (1923–2009) of the

RIAE and Masamichi Kato of School of Medicine, Hokkaido University.

2.5 Progress of Bioelectromagnetism in the Twentieth Century

It has passed over 200 years since the discovery of animal electricity by Galvani and the discussion

between Galvani and Volta. During these times, many researchers had engaged in the research of bio-

electromagnetism. In addition, the invention of instruments brought about great innovation in bioelec­

tromagnetism. Afer entering the twentieth century, there have been many instrumental developments.

It advanced from measuring myocardial action potential with a string electrometer by Einthoven

in 1903, the invention of the vacuum tube triode amplifer by Lee de Forest in 1907, the cathode-ray

tube (later called Braun tube) by Karl Ferdinand Braun (1850–1918), a German inventor, professor at

University of Straßburg, in 1897, and recordings of nerve action potential by Erlanger (1874–1965), an

American physiologist, professor at Washington University, in 1929. Te use of bioelectric and biomag­

netic phenomena has been the majority in bioelectromagnetism. Teir successful use is parallel to the

invention and development of the instruments.

2.5.1 Bioelectricity

Bioelectricity is a fundamental process of all living systems and is the study of electrical phenomena

generated in living systems. Te electrical phenomena include inherent properties of the cells, such as

membrane potential, action potential, and propagation of the potential.

2.5.1.1 Bioelectric Source

Historically, since the great Italian scientists such as Galvani, Volta, and Matteucci carried out well-

known experiments on nerve and muscle excitation, there had also been many physiologists. In particu­

lar, scientists of the school of the University of Berlin, such as Müller and his pupils du Bois Reymond,

Helmholtz, etc. had produced great contributions. Two of the greatest pupils followed Müller’s study, du

Bois-Reymond detected the action current of the nerve, and his colleague, Helmholtz determined the

velocity of the action current. Before the end of the nineteenth century, the electrical nature of the action

potential was established from the studying of the German school.

About 45 years afer Matteucci’s experiment, Augustus Desirè Waller (1856–1922), British physiolo­

gist in 1887, showed the possibility to record the waveforms of the human heart potential from the body