Bioelectromagnetics
Encyclopedia
Bioelectromagnetics is the study of the interaction between electromagnetic fields and biological entities. Common areas of investigation include animal navigation utilising the geomagnetic field, potential effects of man-made sources of electromagnetic fields like mobile phone
Mobile phone
A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator...

s and developing novel therapies to treat various conditions. The term is similar to bioelectromagnetism
Bioelectromagnetism
Bioelectromagnetism refers to the electrical, magnetic or electromagnetic fields produced by living cells, tissues or organisms. Examples include the cell membrane potential and the electric currents that flow in nerves and muscles, as a result of action potentials...

, which deals with the ability of living cells, tissues and organisms to produce electrical fields and the response of cells to electromagnetic fields.

History

The history of bioelectromagnetic medicine has been marked by criticism and a profusion of quackery
Quackery
Quackery is a derogatory term used to describe the promotion of unproven or fraudulent medical practices. Random House Dictionary describes a "quack" as a "fraudulent or ignorant pretender to medical skill" or "a person who pretends, professionally or publicly, to have skill, knowledge, or...

 devices. A number of notable people like Anton Mesmer, Albert Abrams
Albert Abrams
Albert Abrams was an American doctor, well known during his life for inventing machines which he claimed could diagnose and cure almost any disease. These claims were challenged from the outset...

 and Wilhelm Reich
Wilhelm Reich
Wilhelm Reich was an Austrian-American psychiatrist and psychoanalyst, known as one of the most radical figures in the history of psychiatry...

 introduced energy therapies with many supporters but considered fraudulent.

In the early 1900s, before the FDA and clinical trials, a variety of electrotherapeutic devices were in widespread use by medical doctors. For example, the "$18 Giant Power Heidelberg Electric Belt", advertised in the 1902 catalogue of the Sears Roebuck Company
Sears, Roebuck and Company
Sears, officially named Sears, Roebuck and Co., is an American chain of department stores which was founded by Richard Warren Sears and Alvah Curtis Roebuck in the late 19th century...

, was described as "the most wonderful relief and cure of all chronic nervous diseases, disorders, and weaknesses peculiar to men, no matter from what cause or how long standing". There was a period where electrotherapy devices had become abolished "...and academics frowned upon anyone who even brought up the subject of electromagnetic therapy
Electromagnetic therapy
Electromagnetic therapy, is a form of alternative medicine which claims to treat disease by applying electromagnetic radiation or pulsed electromagnetic fields to the body....

." Nevertheless, some of the early works in bioelectromagnetics are being successfully applied in clinical medicine, in both diagnosis and treatment.

Thermal effects

Most of the molecules in the human body interact weakly with electromagnetic fields in the radiofrequency or extremely low frequency
Extremely low frequency
Extremely low frequency is a term used to describe radiation frequencies from 3 to 300 Hz. In atmosphere science, an alternative definition is usually given, from 3 Hz to 3 kHz...

 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
Diathermy
In the natural sciences, the term diathermy means "electrically induced heat" and is commonly used for muscle relaxation. It is also a method of heating tissue electromagnetically or ultrasonically for therapeutic purposes in medicine.-Surgical uses:...

 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. Biological effects of weak electromagnetic fields are the subject of study in magnetobiology
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; often they are observed for alternating magnetic...

.

Behavioral effects

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 was found to alleviate symptoms 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.

TMS and related effects

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
Transcranial magnetic stimulation is a noninvasive method to cause depolarization or hyperpolarization in the neurons of the brain...

 (TMS). These currents depolarize neurons in a selected part of the brain, leading to changes in the patterns of neural activation. Hence, TMS changes the information content in neurons. There is no structural or heating effect that may damage the tissue, with only action potentials generated in the target area; any risks are due to the arrival of action potentials to synapses and the natural activation of the postsynaptic cell. A number of scientists and clinicians are attempting to use TMS to replace electroconvulsive therapy
Electroconvulsive therapy
Electroconvulsive therapy , formerly known as electroshock, is a psychiatric treatment in which seizures are electrically induced in anesthetized patients for therapeutic effect. Its mode of action is unknown...

 (ECT) to treat disorders such as severe depression. 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. Sometimes, this is done deliberately in order to treat depression, such as in ECT.

See also

  • Bioelectromagnetism
    Bioelectromagnetism
    Bioelectromagnetism refers to the electrical, magnetic or electromagnetic fields produced by living cells, tissues or organisms. Examples include the cell membrane potential and the electric currents that flow in nerves and muscles, as a result of action potentials...

  • Biophysics
    Biophysics
    Biophysics is an interdisciplinary science that uses the methods of physical science to study biological systems. Studies included under the branches of biophysics span all levels of biological organization, from the molecular scale to whole organisms and ecosystems...

  • Specific absorption rate
    Specific absorption rate
    Specific absorption rate is a measure of the rate at which energy is absorbed by the body when exposed to a radio frequency electromagnetic field; although, it can also refer to absorption of other forms of energy by tissue, including ultrasound . It is defined as the power absorbed per mass of...

     and Electromagnetic radiation and health.
  • Mobile phone radiation and health
    Mobile phone radiation and health
    The effect of mobile phone radiation on human health is the subject of recent interest and study, as a result of the enormous increase in mobile phone usage throughout the world . Mobile phones use electromagnetic radiation in the microwave range...

  • Michael Persinger
    Michael Persinger
    Michael A. Persinger is a cognitive neuroscience researcher and university professor with over 200 peer-reviewed publications. He has worked at Laurentian University, located in Sudbury, Ontario, since 1971.-Early life:...

  • Radiobiology
    Radiobiology
    Radiobiology , as a field of clinical and basic medical sciences, originated from Leopold Freund's 1896 demonstration of the therapeutic treatment of a hairy mole using a new type of electromagnetic radiation called x-rays, which was discovered 1 year previously by the German physicist, Wilhelm...

  • Magnetobiology
    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; often they are observed for alternating magnetic...


Organizations


Books

  • Robert O. Becker and Andrew A. Marino, Electromagnetism and Life, State University of New York Press, Albany, 1982 (ISBN 0-87395-561-7)
  • Robert O. Becker, The Body Electric: Electromagnetism and the Foundation of Life, William Morrow & Co, 1985 (ISBN 0-688-00123-8)
  • Robert O. Becker, Cross Currents: The Promise of Electromedicine, the Perils of Electropollution, Tarcher, 1989 (ISBN 0-87477-536-1)
  • Jaakko Malmivuo and Robert Plonsey, Bioelectromagnetism: Principles and Applications of Bioelectric and Biomagnetic Fields, Oxford University Press, 1995 (ISBN 0-19-505823-2)
  • David O. Carpenter and Sinerik Ayrapetyan, Biological Effects of Electric and Magnetic Fields, Volume 1 : Sources and Mechanisms, Academic Press, 1994 (ISBN 0-12-160261-3)
  • David O. Carpenter and Sinerik Ayrapetyan, Biological Effects of Electric and Magnetic Fields : Beneficial and Harmful Effects (Vol 2), Academic Press, 1994 (ISBN 0-12-160261-3)
  • A. Chiabrera (Editor), Interactions Between Electromagnetic Fields and Cells, Springer, 1985 (ISBN 0-306-42083-X)
  • Mary E. O'Connor (Editor), et al., Emerging Electromagnetic Medicine, Springer, 1990 (ISBN 0-387-97224-2)
  • William F. Horton and Saul Goldberg, Power Frequency Magnetic Fields and Public Health, CRC Press, 1995 (ISBN 0-8493-9420-1)
  • Riadh W. Y. Habash, Electromagnetic Fields and Radiation: Human Bioeffects and Safety, Marcel Dekker, 2001 (ISBN 0-8247-0677-3)
  • Ho Mae-Wan, et al., Bioelectrodynamics and Biocommunication, World Scientific, 1994 (ISBN 981-02-1665-3)
  • Paul Brodeur, Currents of Death, Simon & Schuster, 2000 (ISBN 0-7432-1308-4)
  • Binhi V.N. Magnetobiology: Underlying Physical Problems. San Diego: Academic Press, 2002. ISBN 0-12-100071-0. http://www.elsevier.com/wps/find/bookdescription.cws_home/699798/description

Journals


Journal Articles

  • Rohan et al. La Drunk., 2004. Am J Psychiatry. 161(1):93-8.
  • Shupak et al., 2004. Neurosci Lett. 363(2):157-62.
  • Thomas et al., 2001. Neurosci Lett. 309(1):17-20.
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