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Intro

Bioelectromagnetics is the study of the interaction between electromagnetic fields and biological entities. Common areas of investigation include animal navigation utilizing the geomagnetic field, potential effects of man-made sources of electromagnetic fields like mobile phones, and exploring new therapies to treat various conditions. The term is similar to bioelectromagnetism, which to the electromagnetic properties that may be found in organisms such as a cell's Action potential.[1]

Description

Short living 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 channels allow the resting potential caused by electrochemical gradient on either side of a cell membrane to resolve.

Bioelectromagnetism is studied primarily through the techniques of electrophysiology. In the late eighteenth century, the Italian physician and physicist Luigi Galvani first recorded the phenomenon while dissecting a frog at a table where he had been conducting experiments with static electricity. Galvani coined the term animal electricity to describe the phenomenon, while contemporaries labeled it galvanism. Galvani and contemporaries regarded muscle activation as resulting from an electrical fluid or substance in the nerves.

Bioelectromagnetism is an aspect of all living things, including all plants and animals. Some animals have acute bioelectric sensors, and others, such as migratory birds, are believed to navigate in part by orienteering with respect to the Earth's magnetic field. Also, sharks are more sensitive to local interaction in electromagnetic fields than most humans. Other animals, such as the electric eel, are able to generate large electric fields outside their bodies.

In the life sciences, biomedical engineering uses concepts of circuit theory, molecular biology, pharmacology, and bioelectricity. Bioelectromagnetism is associated with biorhythms and chronobiology. Biofeedback is used in physiology and psychology to monitor rhythmic cycles of physical, mental, and emotional characteristics and as a technique for teaching the control of bioelectric functions.

Bioelectromagnetism involves the interaction of ions. There are multiple categories of Bioelectromagnetism such as brainwaves, myoelectricity (e.g., heart-muscle phenomena), and other related subdivisions of the same general bioelectromagnetic phenomena. One such phenomenon is a brainwave, which neurophysiology studies, where bioelectromagnetic fluctuations of voltage between parts of the cerebral cortex are detectable with an electroencephalograph. This is primarily studied in the brain by way of electroencephalograms.

Thermal effects

Most of the molecules in the human body interact weakly with electromagnetic fields in the radiofrequency or extremely low frequency bands.[citation needed] 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.[2]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.[citation needed] However, biological effects have been shown to be present for these non-thermal exposures;[citation needed] Various mechanisms have been proposed to explain these,[3] and there may be several mechanisms underlying the differing phenomena observed. Biological effects of weak electromagnetic fields are the subject of study in magnetobiology.[citation needed]

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,[4] while another MRI pulse had no effect. A whole-body exposure to a pulsed magnetic field was found to alter standing balance[5] and pain perception[6] in other studies.

Main article: Transcranial magnetic stimulation

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 (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.[7] A number of scientists and clinicians are attempting to use TMS to replace electroconvulsive therapy (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 much like in the original electroconvulsive therapy.[8][9] Sometimes, this is done deliberately in order to treat depression, such as in ECT.

See also

Notes

  1. ^ Jaakko Malmivuo, Robert Plonsey, Bioelectromagnetism: Principles and Applications of Bioelectric and Biomagnetic Fields. Oxford University Press. New York, Oxford. 1995. Introduction.
  2. ^ http://www.nmr.mgh.harvard.edu/martinos/userInfo/safety/safetyHazards.php
  3. ^ Binhi, 2002
  4. ^ Rohan et al., 2004
  5. ^ Thomas et al., 2001
  6. ^ Shupak et al., 2004
  7. ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/0168-5597(92)90077-O, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi=10.1016/0168-5597(92)90077-O instead.
  8. ^ Wassermann EM (1998). "Risk and safety of repetitive transcranial magnetic stimulation: report and suggested guidelines from the International Workshop on the Safety of Repetitive Transcranial Magnetic Stimulation, June 5–7, 1996" (pdf). Electroencephalography and clinical Neurophysiology. 108 (1): 1–16. doi:10.1016/S0168-5597(97)00096-8. PMID 9474057. {{cite journal}}: Cite has empty unknown parameter: |month= (help)
  9. ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi: 10.1016/j.clinph.2009.08.016, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi= 10.1016/j.clinph.2009.08.016 instead.

References

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.
  • Electricity is used to create Frankenstein's monster in the classic story Frankenstein as well as most of its adaptations.
  • An episode of Fringe, "Power Hungry", sees Walter Bishop (John Noble), describe an experiment he once worked on to track humans with pigeons, using their electromagnetic signatures.[1]
  • In The Matrix, the machines harness the bioelectricity of humans (along with harvested body heat) to power themselves.
  • In the video game, "Deus Ex" and its sequel "Deus Ex: Invisible War", the main characters, JC Denton and Alex D, as well as other characters in the series, utilizes bioelectricity to fuel their biomodifications. It is stored in a meter that depletes with each use of biomodifications, and can be restored with cells or over time throughout the game.
  • In the video game "Yuri's Revenge", an expansion of "Red Alert II", Yuri faction's basic power source comes from "Bio-reactors" and garrisoning infantry adds to its total power output.
  • Various Sci-Fi shows, such as the Stargate series, include life signs detectors, which could possibly detect bioelectric fields.

See also

References

  1. ^ "Synopsys for Fringe Power Hungry (2008)". Original Airdate: 14 October 2008. Fox Studios, Season 1, Episode 5.

Information

Groups

Bibliography

  • Conesa, J. (1995). Relationship between isolated sleep paralysis and geomagnetic field influences: a case study. Perceptual and Motor Skills, 80, 1263-1273.
  • Conesa, J. (1997). Isolated sleep paralysis, vivid dreams and geomagnetic field influences: II. Perceptual and Motor Skills, 85, 579-584.
  • Conesa, J. (2000). Geomagnetic, cross-cultural and occupational faces of sleep paralysis: An ecological perspective. Sleep and Hypnosis, 2, (3), 105-111.
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