Biomagnetism is the phenomenon of
magnetic field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and t ...
s ''produced'' by living organisms; it is a subset of
bioelectromagnetism. In contrast, organisms' use of magnetism in navigation is
magnetoception
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). The se ...
and the study of the magnetic fields' ''effects'' on organisms is ''
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; ...
''. (The word biomagnetism has also been used loosely to include magnetobiology, further encompassing almost any combination of the words magnetism, cosmology, and biology, such as "magnetoastrobiology".)
The origin of the word biomagnetism is unclear, but seems to have appeared several hundred years ago, linked to the expression "
animal magnetism
Animal magnetism, also known as mesmerism, was a protoscientific theory developed by German doctor Franz Mesmer in the 18th century in relation to what he claimed to be an invisible natural force (''Lebensmagnetismus'') possessed by all liv ...
". The present scientific definition took form in the 1970s, when an increasing number of researchers began to measure the magnetic fields produced by the human body. The first valid measurement was actually made in 1963, but the field of research began to expand only after a low-noise technique was developed in 1970.
[{{cite journal , last1=Cohen , first1=David , last2=Edelsack , first2=Edgar A. , last3=Zimmerman , first3=James E. , title=Magnetocardiograms taken inside a shielded room with a superconducting point contact magnetometer , journal=Applied Physics Letters , publisher=AIP Publishing , volume=16 , issue=7 , year=1970 , issn=0003-6951 , doi=10.1063/1.1653195 , pages=278–280, bibcode=1970ApPhL..16..278C ] Today the community of biomagnetic researchers does not have a formal organization, but international conferences are held every two years, with about 600 attendees. Most conference activity centers on the MEG (
magnetoencephalogram
Magnetoencephalography (MEG) is a functional neuroimaging technique for mapping brain activity by recording magnetic fields produced by electrical currents occurring naturally in the brain, using very sensitive magnetometers. Arrays of SQUIDs ( ...
), the measurement of the magnetic field of the brain.
Prominent researchers
*
David Cohen
*
John Wikswo
John Peter Wikswo, Jr. (born October 6, 1949) is a biological physicist at Vanderbilt University. He was born in Lynchburg, Virginia, United States.
Wikswo is noted for his work on biomagnetism and cardiac electrophysiology.
Graduate school
...
*
Samuel Williamson
See also
*
Bioelectrochemistry
Bioelectrochemistry is a branch of electrochemistry and biophysical chemistry concerned with electrophysiological topics like cell electron-proton transport, cell membrane potentials and electrode reactions of redox enzymes.
History
The beginnin ...
*
Human magnetism
Human magnetism is a popular name for an alleged ability of some people to attract objects to their skin. People alleged to have such an ability are often called human magnets. Although metal objects are the most popular, some are also alleged t ...
*
Magnetocardiography
Magnetocardiography (MCG) is a technique to measure the magnetic fields produced by electrical currents in the heart using extremely sensitive devices such as the superconducting quantum interference device (SQUID). If the magnetic field is meas ...
*
Magnetoception
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). The se ...
- sensing of magnetic fields by organisms
*
Magnetoelectrochemistry
*
Magnetoencephalography
Magnetoencephalography (MEG) is a functional neuroimaging technique for mapping brain activity by recording magnetic fields produced by electrical currents occurring naturally in the brain, using very sensitive magnetometers. Arrays of SQUIDs (s ...
*
Magnetogastrography
Magnetogastrography is the science of recording magnetogastrograms (MGGs). Magnetogastrograms are recordings of magnetic fields resulting from electrical currents in the stomach. The magnetic fields are typically recorded using SQUIDs.
See also
...
*
Magnetomyography
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SQUID
True squid are molluscs with an elongated soft body, large eyes, eight arms, and two tentacles in the superorder Decapodiformes, though many other molluscs within the broader Neocoleoidea are also called squid despite not strictly fitting ...
Notes
Further reading
* Williamson SH, Romani GL, Kaufman L, Modena I, editors. Biomagnetism: An Interdisciplinary Approach. 1983. NATO ASI series. New York: Plenum Press.
* Cohen, D. Boston and the history of biomagnetism. ''Neurology and Clinical Neurophysiology'' 2004; 30: 1.
History of Biomagnetism
Bioelectromagnetics
Magnetism