biomagnetism


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Related to biomagnetism: Bioelectromagnetism

Biomagnetism

The production of a magnetic field by a living object. The living object presently most studied is the human body, for two purposes: to find new techniques for medical diagnosis, and to gain information about normal physiology. Smaller organisms studied include birds, fishes, and objects as small as bacteria; many scientists believe that biomagnetics is involved in the ability of these creatures to navigate. The body produces magnetic fields in two main ways: by electric currents and by ferromagnetic particles. The electric currents are the ion currents generated by the muscles, nerves, and other organs. For example, the same ion current generated by heart muscle, which provides the basis for the electrocardiogram, also produces a magnetic field over the chest; and the same ion current generated by the brain, which provides the basis for the electroencephalogram, also produces a magnetic field over the head. Ferromagnetic particles are insoluble contaminants of the body; the most important of these are the ferromagnetic dust particles in the lungs, which are primarily Fe3O4 (magnetite). Magnetic fields can give information about the internal organs not otherwise available.

These magnetic fields are very weak, usually in the range of 10-14 to 10-9 tesla; for comparison, the Earth's field is about 10-4 T (1 T = 104 gauss, the older unit of field). The fields at the upper end of this range, say stronger than 10-4 T, can be measured with a simple but sensitive magnetometer called the fluxgate; the weaker fields are measured with the extremely sensitive cryogenic magnetometer called the SQUID (superconducting quantum interference device). The levels of the body's fields, whether they are fluctuating or steady, are orders of magnitude weaker than the fluctuating or steady background fields. They can, however, be measured by using either a magnetically shielded room or two detectors connected in opposition so that much of the background is canceled, or a combination of both methods. The organs producing magnetic fields which are of most interest are the brain, the lungs, and the liver. See Electroencephalography, Migratory behavior

biomagnetism

[¦bī·ō′mag·nə‚tiz·əm]
(biophysics)
The production of a magnetic field by a living organism.
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References in periodicals archive ?
We consider our research (experimental and evaluation) design to have heuristic potential and capacity for further development and usage in the studies on biomagnetism. In a simple, non-invasive, objective and blind way, data can be quickly sampled on common, non-protected bird species, also out of the migratory context, and thus seasonally restricted, context.
Kawabata, "Measurement of magnetocardiogram using magnetoresistive sensor," in Abstract Book for the 20th International Conference on Biomagnetism, Biomag 2016, p.
Proceedings of 15th International Conference on Biomagnetism; 2006 Aug 20-26; Vancouver, Canada.
I also knew that there are a host of environmental influences such as Schumann Resonances, circadian rhythms, and biomagnetism that inform and influence the body.
Gulrajani, Bioelectricity and Biomagnetism, John Wiley & Sons, NewYork, NY, USA, 1998.
(1) Institute for Biomagnetism and Biosignalanalysis, University of Munster, Malmedyweg 15, 48149 Munster, Germany
This short book is divided into three chapters: the first presents Brusewitz's master's thesis, the second is devoted to a review of parapsychological research (explicitly excluding research into psychokinesis), and the third is devoted to a summary of research on "biomagnetism, biofields, and holistic biology."