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Bioelectromagnetics, also known as bioelectromagnetism, is the study of the interaction between
electromagnetic field An electromagnetic field (also EM field or EMF) is a classical (i.e. non-quantum) field produced by (stationary or moving) electric charges. It is the field described by classical electrodynamics (a classical field theory) and is the classica ...
s and biological entities. Areas of study include
electromagnetic field An electromagnetic field (also EM field or EMF) is a classical (i.e. non-quantum) field produced by (stationary or moving) electric charges. It is the field described by classical electrodynamics (a classical field theory) and is the classica ...
s produced by living cells, tissues or
organism In biology, an organism () is any life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multicellular o ...
s, the effects of man-made sources of electromagnetic fields like
mobile phone A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive telephone call, calls over a radio freq ...
s, and the application of electromagnetic radiation toward therapies for the treatment of various conditions.


Biological phenomena

Bioelectromagnetism is studied primarily through the techniques of electrophysiology. In the late eighteenth century, the Italian
physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...
and
physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate ca ...
Luigi Galvani first recorded the phenomenon while dissecting a
frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" '' Triadobatrachus'' is ...
at a table where he had been conducting experiments with
static electricity Static electricity is an imbalance of electric charges within or on the surface of a material or between materials. The charge remains until it is able to move away by means of an electric current or electrical discharge. Static electricity is n ...
. Galvani coined the term ''animal electricity'' to describe the phenomenon, while contemporaries labeled it
galvanism Galvanism is a term invented by the late 18th-century physicist and chemist Alessandro Volta to refer to the generation of electric current by chemical action. The term also came to refer to the discoveries of its namesake, Luigi Galvani, spec ...
. Galvani and contemporaries regarded muscle activation as resulting from an electrical fluid or substance in the
nerve A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the ...
s. Short-lived electrical events called action potentials occur in several types of animal cells which are called excitable cells, a category of cell include neurons, muscle cells, and endocrine cells, as well as in some plant cells. These action potentials are used to facilitate inter-cellular communication and activate intracellular processes. The physiological phenomena of action potentials are possible because
voltage-gated ion channel Voltage-gated ion channels are a class of transmembrane proteins that form ion channels that are activated by changes in the electrical membrane potential near the channel. The membrane potential alters the conformation of the channel proteins, ...
s allow the resting potential caused by electrochemical gradient on either side of a cell membrane to resolve.. Several animals are suspected to have the ability to sense electromagnetic fields; for example, several aquatic animals have structures potentially capable of sensing changes in voltage caused by a changing magnetic field, while migratory birds are thought to use
magnetoreception Magnetoreception is a sense which allows an organism to detect the Earth's magnetic field. Animals with this sense include some arthropods, molluscs, and vertebrates (fish, amphibians, reptiles, birds, and mammals, though not humans). Th ...
in navigation.


Bioeffects of electromagnetic radiation

Most of the molecules in the human body interact weakly with electromagnetic fields in the
radio frequency Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the uppe ...
or extremely low frequency bands. One such interaction is absorption of energy from the fields, which can cause tissue to heat up; more intense fields will produce greater heating. This can lead to biological effects ranging from muscle relaxation (as produced by a diathermy device) to burns. Many nations and regulatory bodies like the International Commission on Non-Ionizing Radiation Protection have established safety guidelines to limit EMF exposure to a non-thermal level. This can be defined as either heating only to the point where the excess heat can be dissipated, or as a fixed increase in temperature not detectable with current instruments like 0.1 °C. However, biological effects have been shown to be present for these non-thermal exposures; Various mechanisms have been proposed to explain these, and there may be several mechanisms underlying the differing phenomena observed. Many behavioral effects at different intensities have been reported from exposure to magnetic fields, particularly with pulsed magnetic fields. The specific pulseform used appears to be an important factor for the behavioural effect seen; for example, a pulsed magnetic field originally designed for spectroscopic MRI, referred to as Low Field Magnetic Stimulation, was found to temporarily improve patient-reported mood in bipolar patients, while another MRI pulse had no effect. A whole-body exposure to a pulsed magnetic field was found to alter standing balance and pain perception in other studies. A strong changing magnetic field can induce electrical currents in conductive tissue such as the brain. Since the magnetic field penetrates tissue, it can be generated outside of the head to induce currents within, causing
transcranial magnetic stimulation Transcranial magnetic stimulation (TMS) is a noninvasive form of brain stimulation in which a changing magnetic field is used to induce an electric current at a specific area of the brain through electromagnetic induction. An electric pulse gener ...
(TMS). These currents depolarize neurons in a selected part of the brain, leading to changes in the patterns of neural activity. In repeated pulse TMS therapy or rTMS, the presence of incompatible EEG electrodes can result in electrode heating and, in severe cases, skin burns. A number of scientists and clinicians are attempting to use TMS to replace
electroconvulsive therapy Electroconvulsive therapy (ECT) is a psychiatric treatment where a generalized seizure (without muscular convulsions) is electrically induced to manage refractory mental disorders.Rudorfer, MV, Henry, ME, Sackeim, HA (2003)"Electroconvulsive t ...
(ECT) to treat disorders such as severe depression and hallucinations. Instead of one strong electric shock through the head as in ECT, a large number of relatively weak pulses are delivered in TMS therapy, typically at the rate of about 10 pulses per second. If very strong pulses at a rapid rate are delivered to the brain, the induced currents can cause convulsions much like in the original
electroconvulsive therapy Electroconvulsive therapy (ECT) is a psychiatric treatment where a generalized seizure (without muscular convulsions) is electrically induced to manage refractory mental disorders.Rudorfer, MV, Henry, ME, Sackeim, HA (2003)"Electroconvulsive t ...
. Sometimes, this is done deliberately in order to treat depression, such as in ECT.


Effects of electromagnetic radiation on human health

While health effects from extremely low frequency (ELF) electric and magnetic fields (0 to 300 Hz) generated by power lines, and radio/microwave frequencies (RF) (10 MHz - 300 GHz) emitted by radio antennas and wireless networks have been well studied, the intermediate range (IR) (300 Hz to 10 MHz) has been studied far less. Direct effects of low power radiofrequency electromagnetism on human health have been difficult to prove, and documented life-threatening effects from radiofrequency electromagnetic fields are limited to high power sources capable of causing significant thermal effects and medical devices such as pacemakers and other electronic implants. However, many studies have been conducted with electromagnetic fields to investigate their effects on cell metabolism, apoptosis, and tumor growth. Electromagnetic radiation in the intermediate frequency range has found a place in modern medical practice for the treatment of bone healing and for nerve stimulation and regeneration. It is also approved as cancer therapy in form of Tumor Treating Fields, using alternating electric fields in the frequency range of 100–300 kHz. Since some of these methods involve magnetic fields that invoke electric currents in biological tissues and others only involve electric fields, they are strictly speaking electrotherapies albeit their application modi with modern electronic equipment have placed them in the category of bioelectromagnetic interactions.


See also

* Bioelectrogenesis *
Biomagnetism Biomagnetism is the phenomenon of magnetic fields ''produced'' by living organisms; it is a subset of bioelectromagnetism. In contrast, organisms' use of magnetism in navigation is magnetoception and the study of the magnetic fields' ''effects'' on ...
* Bioelectricity * Bioelectrochemistry *
Bioelectrodynamics Bioelectrodynamics is a branch of medical physics and bioelectromagnetism which deals with rapidly changing electric and magnetic fields in biological systems, i.e. high frequency endogenous electromagnetic phenomena in living cells. Unlike the even ...
* Biophotonics *
Biophysics Biophysics is an interdisciplinary science that applies approaches and methods traditionally used in physics to study biological phenomena. Biophysics covers all scales of biological organization, from molecular to organismic and populations. ...
*
Electric fish An electric fish is any fish that can generate electric fields. Most electric fish are also electroreceptive, meaning that they can sense electric fields. The only exception is the stargazer family. Electric fish, although a small minority, inc ...
* Electrical brain stimulation *
Electroencephalography Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocor ...
* Electromagnetic radiation and health * Electromyography * Electrotaxis * Kirlian photography *
Magnetobiology Magnetobiology is the study of biological effects of mainly weak static and low-frequency magnetic fields, which do not cause heating of tissues. Magnetobiological effects have unique features that obviously distinguish them from thermal effects; ...
* Magnetoception *
Magnetoelectrochemistry Magnetoelectrochemistry is a branch of electrochemistry dealing with magnetic effects in electrochemistry. History These effects have been supposed to exist since the time of Michael Faraday. There have also been observations on the existence of Ha ...
* Mobile phone radiation and health *
Radiobiology Radiobiology (also known as radiation biology, and uncommonly as actinobiology) is a field of clinical and basic medical sciences that involves the study of the action of ionizing radiation on living things, especially health effects of radiation ...
* Specific absorption rate *
Transcutaneous electrical nerve stimulation Transcutaneous electrical nerve stimulation (TENS or TNS) is the use of electric current produced by a device to stimulate the nerves for therapeutic purposes. TENS, by definition, covers the complete range of transcutaneously applied currents ...


Notes


References


Organizations


The Bioelectromagnetics Society
(BEMS)
European BioElectromagnetics Association
(EBEA)
Society for Physical Regulation in Biology and Medicine
(SPRBM) (formerly the Bioelectrical Repair and Growth Society, BRAGS)
International Society for Bioelectromagnetism
(ISBEM)
The Bioelectromagnetics Lab at University College Cork, Ireland

Institute of Bioelectromagnetism

Vanderbilt University, Living State Physics Group, archived page

Ragnar Granit Institute

Institute of Photonics and Electronics AS CR, Department of Bioelectrodynamics


Books

* Becker, Robert O.; Andrew A. Marino

State University of New York Press, Albany, 1982. . * Becker, Robert O.; ''The Body Electric: Electromagnetism and the Foundation of Life'', William Morrow & Co, 1985. . * Becker, Robert O.; ''Cross Currents: The Promise of Electromedicine, the Perils of Electropollution'', Tarcher, 1989. . * Binhi, V.N., ''Magnetobiology: Underlying Physical Problems''. San Diego: Academic Press, 2002. . * Brodeur Paul; ''Currents of Death'', Simon & Schuster, 2000. . * Carpenter, David O.; Sinerik Ayrapetyan, ''Biological Effects of Electric and Magnetic Fields'', Volume 1 : Sources and Mechanisms, Academic Press, 1994. . * Carpenter, David O.; Sinerik Ayrapetyan, ''Biological Effects of Electric and Magnetic Fields : Beneficial and Harmful Effects'' (Vol 2), Academic Press, 1994. . * Chiabrera A. (Editor), ''Interactions Between Electromagnetic Fields and Cells'', Springer, 1985. . * Habash, Riadh W. Y.; ''Electromagnetic Fields and Radiation: Human Bioeffects and Safety'', Marcel Dekker, 2001. . * Horton William F.; Saul Goldberg, ''Power Frequency Magnetic Fields and Public Health'', CRC Press, 1995. . * Mae-Wan, Ho; et al., ''Bioelectrodynamics and Biocommunication'', World Scientific, 1994. . * Malmivuo, Jaakko; Robert Plonsey

Oxford University Press, 1995. . * O'Connor, Mary E. (Editor), et al., ''Emerging Electromagnetic Medicine'', Springer, 1990. .


Journals

* '' Bioelectromagnetics'' * '' Bioelectrochemistry'' * '' European Biophysics Journal'' *
International Journal of Bioelectromagnetism
', ISBEM, 1999–present, ()
''BioMagnetic Research and Technology'' archive
(no longer publishing) *
Biophysics
', English version of the Russian "Biofizika" () * ''Radiatsionnaya Bioliogiya Radioecologia'' ("Radiation Biology and Radioecology", in Russian) ({{ISSN, 0869-8031)


External links



by Jaakko and Plonsey.

Physiology Radiobiology Biology Electrophysiology ru:Магнитобиология