| MadSci Network: Neuroscience |
Electromagnetism plays a significant role on the human brain - which is relatively new information, but the effects have been and continue to be characterized by scientific research. There are different forms of electromagnetism to consider. First, is the Earth's natural electromagnetic field. It has both a static and a dynamic quality. The static quality is just a stagnant field which surrounds the Earth. The dynamic quality is caused by, mainly, the inner core of the Earth, which is liquid, in motion. The strength of the field is measured in Teslas (T). The Earth's magnetic field intensity is roughly between 25,000 - 65,000 nT, depending on where you are. Life on Earth, including us, of course, evolved with this field, and it has been becoming increasing clear that animals can detect and use this field for such things as migration patterns, sleep patterns, etc. Artificial magnetic fields are generated by everything we do that uses electricity, everything. It is now generally accepted that there are fairly well defined negative health effects as a result of chronic exposure to these fields. The exact mechanisms aren't entirely well understood, but we have learned a little bit about the mechanisms, enough to support definitive science. One mechanism involves what is referred to as ion channeling. Cells pump ions, in many cases trace metals such as calcium and magnesium, as part of their operating cycle. Dynamic magnetic fields such as 60Hz AC has been demonstrated to disturb this natural cycle. Another effect is what is referred to as 'following.' It has been demonstrated that when an animal brain is exposed to an alternating magnetic field, again - such as a 60Hz AC field, the brain, which is sensitive to magnetic fields will begin to mimic, or 'follow' the pulsing of the field. This can be definitively measured by electroencephalograph in humans, demonstrating that overall brain wave patterns have been disrupted by the artificial field. This effects cognitive, general health, sleep patterns, and behavior patterns. For instance, it has been demonstrated that even a relatively weak 60Hz field (much weaker than the Earth's field) can induce immediate physical violence in primates. Birds can be demonstrated to completely loose their sense of direction in the presence of magnetic fields. There are a multitude of other models which are currently being examined. An overall general picture is that animals evolved with the Earth's field, and animal brains have evolved in such a way as to be sensitive to it. In fact, only a few varieties of reptiles which happen to be non-migratory are known to be insensitive to the Earth's magnetic field. Artificial fields, in general, tend to be of greater strength than the Earth's magnetic field because we are much closer to the source, in most cases. The wiring in your house, the television, the refrigerator, blender, microwave, light bulbs, every appliance, power lines, etc. are packed with EMF (electromagnetic or electromotive force) and in close proximity. A multitude of studies have been done regarding the negative health effects of these fields and in general, the outlook is not good. Behavioral effects and health effects, such as cancer, have been confirmed by multiple studies. In general, the medical community and various public comities are not prepared to openly state that a health problem exists as a result of artificial electromagnetic fields. This is because the evidence is young and in its early stages of discovery, and it may be premature to make an open statement that could ltteraly cost uncountable billions of dollars to fix. Also, keep in mind that these organizations are concerned with public safety and health, and unless the health risk is relatively high, such as with cigarette smoking, public policy will not be made. On the other hand, the same groups have proposed guidelines and standards for EMF emissions, based on the same information. The result of these standards is, as a for instance, computer monitors emit lower EMF than they used to. A list of links to reputable sources of information is prided here as references: The Earth's magnetic field: http://www.ultramag.com/page1.htm http://www.ih2000.net/catholicvoice/Gen_Evol/ques4.html http://ssdoo.gsfc.nasa.gov/education/lectures/magnetosphere.html http://www.sciam.com/askexpert/geology/geology4.html http://www.unb.ca/courses/biol4775/SPAGES/SPAGE15.HTM http://www.ngdc.noaa.gov/seg/potfld/faqgeom.shtml Magnetic fields and health: Links that say there is no problem: http://ehpnet1.niehs.nih.gov/docs/2000/suppl-1/79-100mccann/abstract.html http://www.junkscience.com/news/nrc-emf.html http://www.mcw.edu/gcrc/cop/static-fields-cancer-FAQ/toc.html Links that suggest a problem: A HUGE list of references from the National Institutes of Health: http://www.niehs.nih.gov/emfrapid/html/WGReport/References.html http://www.arbsky.se/elmagn/engtext.htm http://www.meb.uni-bonn.de/cancernet/600346.html
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