The bioelectric phenomena form an essential part of the living organisms in cell functioning. This encompasses the processing and transfer of essential information by the nerve cells within the organs of the body, the control of the muscle functioning, and between the body and surrounding environments. As such, the bioelectric phenomena provide a fast and reliable means of carrying out disease diagnosis, especially in neurological and muscular disorders to return the human body into normal functioning. With the improvements in biomagnetic measurement and simulation techniques, bioelectromagnetism has played an integral role in scientific research and health care. This paper seeks to discuss the concept of bioelectricmagnetism, its history, and applications in medicine.
Bioelectromagnetism is defined as the study of the interaction between biological entities and electromagnetic fields (Malmivuo & Plonsey, 1995). Therefore, bioelectromagnetism is concerned with electromagnetic fields that are produced by living organisms, tissues, and cells as well as the bioluminescent bacteria. Moreover, it involves the use of geomagnetic fields by animals for locomotion, the development of new treatment therapies, and the effects of electromagnetic fields that are emitted by man-made products, such as mobile phones. However, Valdmanis and Cipijs (2008) explain that bioelectromagnetism is the ability of living tissues, cells, and organisms to produce electric fields and the response the cells respond to electromagnetic fields.
There are electrical currents in the living body that produce magnetic fields extending outside the body. However, these electrical currents can be influenced by external magnets and as thus the changes in the body’s natural fields are capable of producing behavioral and physical changes (Malmivuo & Plonsey, 1995).
The Basic phenomena of Magnetic Fields
Magnetic fields are defined as the magnetic forces that are produced by moving electric currents as electrons move through a medium. The strength of such a magnetic field depends on the electric current flowing through the medium with the greater the current the greater the magnetic field. An electromagnetic field is composed of both magnetic and electric fields with fluctuating magnetic fields being characterized by the frequency of the fluctuation per second and is measured in hertz.
However, the distance traveled by the field determines the strength of the magnetic field as determined by wave motions. These waves move at the speed of light and have an inverse relationship with the frequency of the electromagnetic field. The electromagnetic fields are capable of carrying energy throughout the space and are represented in the electromagnetic spectrum, which includes radio, television, microwave, visible light, and x-ray frequencies (Kauppinen, Hyttinen & Malmivuo, 2006). However, a prolonged exposure to the ionizing electromagnetic radiation can result into dislodging of electrons from molecules or atoms.
Bioelectric signals emanate from the excitable tissues of the body, which encompass the muscle and nerve cells (Wheeler, 2016). These signals work together with other spontaneous bioelectric signals, such as the electrooculogram, EOG produced by the static electric polarization of the eye movement. The EOG and electronystagmogram, ENG are crucial in clinical applications. Electroretinogram, ERG refers to the retina’s electric response to light and is important in studying the bioelectric signals and their behavior. This involves sending of visual information from the retina to the central nervous system using the optic nerve, which forms neurological bioelectromagnetism (Starzynski, Szmurlo & Sawicki, 2009).
History of Bioelectromagnetism
Bioelectromagnetism has been applied in medicine since the time of the ancient Egyptians around 4000 B.C. This was first discovered by fishermen who after catching an electric spearfish, the fish produced electric shocks that prompted the fishermen to release it. Electrophysiology techniques enabled scientists to study bioelectromagnetism and as such, in the late 18th century, Luigi Galvani recorded a phenomenon of static electricity through experiments with frogs, which led to a conclusion that there is electrical fluid in the nerves, which leads to muscle activation. However, expansions of the field were made in the ninetieth century with the first real diagnostics being made (Verschuur, 1996).
However, with the invention of Leyden jar, advances in bioelectromagnetism began to take place. These studies led to the invention of the galvanic stimulation and more advances by Jan Swammerdam on the effects of controlled muscle stimulations. Measures were made using a coil with the aid of a magnetic needle deflection and another needle placed in opposite direction but on the same axis to compensate for against the static field of the earth. In 1963, Richard McFee made the first biomagnetic measurement using the magnetocardiogram (Malmivuo & Plonsey, 1995).
As improvements in modern electronics were done and so did bioelectromagnetism improve to the present day EEG and electrocardiography. This has been fueled by a breakthrough in microelectronics thereby making equipment portable and better in terms of their diagnostic power. Further, the field of bioelectromagnetism was further opened up by the ability of scientists to measure electric currents flowing through ion channels of the cell membrane and thus leading to breakthroughs in molecular biology to come up with new pharmaceuticals (Kauppinen et al., 2006).
Studies on Bioelectromagnetism
Studies are underway to ascertain the mechanisms under which electromagnetic fields create biological effects and as such the cell membrane has been found as the primary location for electromagnetic field activity on the cell. Scientists have found that the electromagnetic fields that are present at the outer surface of the cell membranes are capable of changing the ligand-receptor interactions, which play an integral role in controlling the internal processes of cells by changing the state of membrane molecules (Verschuur, 1996).
Different studies are also looking into the effects of endogenous electromagnetic fields on body organs and tissues. The electrical activity also displays macroscopic patterns with information that is medically useful, for instance, the procedures of electrocardiography and electroencephalography depend on the action of the heart muscle and central nervous system to produce endogenous electromagnetic fields. This has spurred research on the possibilities of weak electromagnetic fields being related to other body tissue and organs’ nerve activity which might be of diagnostic value (Valdmanis & Cipijs, 2008).
Importance of Bioelectromagnetism
Bioelectromagnetism borrows from various disciplines in both engineering and physical sciences, for instance, bioengineering, biophysics, biotechnology, medical physics, biomedical engineering, and medical electronics. Therefore, bioelectromagnetism as a discipline examines the magnetic, electromagnetic, and electric phenomena in biological tissues. Such phenomena include the magnetic fields present in and outside the body, tissues’ intrinsic magnetic and electric properties, how excitable cells respond to magnetic and electric field stimulation, volume conductor electric currents, and the behavior and sources of excitable tissue (Malmivuo & Plonsey, 1995).
The bioelectric characteristic of the cell membrane is crucial in the functioning of the living organism. This allows the cells in the nervous system to communicate with one another using the electric signals. Bioelectromagnetism has opened up research and the development of electronic instrumentation as well as diagnostic devices for various chronic diseases. For example, the production of implantable cardiac pacemakers has bettered the lives of people with heart problems. Moreover, there are developments of biomagnetic applications to act as alternatives to bioelectric techniques for diagnosis and therapy of medical conditions (Kauppinen et al., 2006).
Further, through bioelectromagnetism, scientists have been able to study how living tissue behaves on organic, cellular as well as subcellular levels through electric current flow measurements using the patch-clamp method as the current flows through single ion channels in the cell membrane (Valdmanis & Cipijs, 2008). There is a potential for bioelectromagnetism being applied in molecular biology thereby improving on pharmaceutical development. Therefore, bioelectromagnetism offers and will continue to provide new and advanced opportunities for therapeutic and diagnostic methods.
Through bioelectromagnetism, it is possible to detect bio-magnetism and bioelectric phenomena using non-invasive methods since non-invasive methods provide information in real time around the body’s volume conductor. Moreover, bioelectromagnetism allows medics to activate the paralyzed regions of the body through the introduction of spatially and temporally controlled electric stimuli. This is done through transmission of signals by the electric nature of biological tissues (Cheng, 1992).
Medical Applications of Bioelectromagnetics
Through bioelectromagnetics, scientists have been able to produce medical devices for the diagnosis and treatment of diseases, for instance, x-ray devices. Moreover, scientists are largely using the nonionizing portion of the electromagnetic spectrum although at low levels. This depends on the classifications whether they are non-thermal or thermal, for example, RF diathermy, RF and laser surgery, and RF hyperthermia. However, the non-thermal applications of non-ionizing radiation are the most crucial bioelectromagnetic modalities in medicine (Verschuur, 1996).
The non-thermal applications mean that they cause no substantial gross heating of tissues and produce minimal noise at physiological temperatures. An example is the microwave resonance therapy, which is used in the treatment of conditions, such as cerebral palsy, chronic pain, hypertension, and the side effects of chemotherapy, neurological disorders, esophagitis, ulcers, and arthritis (Kauppinen et al., 2006). Additionally, doctors use bioelectromagnetic frequencies at acupuncture points to treat these conditions.
As such, the mechanisms of the microwave resonance therapy involve changes in the cell membrane transport as well as chemical mediator production. This follows the earlier belief that biological information is stored in molecular structures, which scientist hold that biological regulation and cellular communication is only possible if biological information is stored in the whole organism in the endogenous electromagnetic field. Therefore, the applications of the bioelectromagnetic fields include neuroendocrine modulations, immune system stimulations, tissue regeneration, electro-acupuncture, osteoarthritis treatment, healing of wounds, stimulation of nerves, and bone repair (Valdmanis & Cipijs, 2008).
In bioelectromagnetism, the independence of the magnetic and electric information can be demonstrated through modeling of the volume conductor to show that the electric field that is generated by the current sources. Studies have thus shown that signals originate from a common source configuration thereby making the information content of the methods similar. On the other hand, bioelectromagnetism gives an analysis of the magnetic and electric stimulation of the brain and nervous system. This is shown by the reciprocity theory through the calculations of the MEG and EEG applications to the magnetic and electric stimulations of the human brain (Malmivuo & Plonsey, 1995). Therefore, a clear understanding of the energy distributions of the bioelectromagnetism with regard to the magnetic and electric stimulations thereby providing room for more accurate experiments on the stimulation of the nervous system.
Moreover, toxins pile up in the body, especially outside of the cells due to poor bio-electric membrane voltage, which makes it possible for the toxins to stick to the membrane. This activity inhibits the natural flow of water into the cells as well as the exit of nucleic waste out of the cells. As a result, the functioning of the cells is compromised until the level whereby toxins penetrate the cell membranes and thus reaching a level whereby the process is irreversible. Moreover, the body’s design has many organs that are attuned to the electromagnetic phenomena. For example, the brain produces electromagnetic fields that are both different and separate from those produced by the heart; a mechanical wave sound is vibrated by the tympanic membrane while the eyes record individual photon packets (McRee & Wachtel, 1982). As such, the human body is actively involved in the production and control of bioelectricity.
Bioelectromagnetism is used in medicine in detoxification whereby the application of electromagnetism leads to the restoration of integrity to the actual membrane itself to return the cell to its normal functioning by being selectively permeable. This leads to proper processing of toxins for elimination whereby the kidneys and liver start to remove more toxins and thereby reducing the overall toxin load in the body. One major application happened in 1892 when Nikola Tesla met with Paul Oudin leading to the production of the “violet ray”, a device that used bioelectromagnetism to treat skin disorders, such as eczema and acne as well as removal of wart and cancer anomalies. The device largely relied on removing the detached toxins on the cell membrane thereby allowing for free movement of the intercellular fluid.
When intense but relatively short-pulsed electric fields are applied to the mammalian cells, a substantial surge in plasma membrane permeability to macromolecules and ions is induced. These pulses target the plasma membrane in addition to interacting with intracellular structures thereby prompting cancer cell death pathways. The process of treatment of superficial solid cancers, commonly known as electrochemotherapy involves subjecting of pulsed electric fields to kVm-1 in duration of a millisecond to microsecond time scale (Malmivuo & Plonsey, 1995). This technique is also used during the process of amplifying microbic deactivation process in water and food treatments.
Therefore, bioelectromagnetism is useful in relieving imbalance within the body and has been instrumental in the treatment of allergies, aging, skin tone, sleep problems, depression, anxiety, and stress as well as a restoring the functioning of the endocrine system and kidneys, and reduction of swelling and inflammation.
Moreover, other studies have reported acute effects of magnetic and electric fields and currents with regard to human bone growth, cutaneous perception, brain evoked potentials, bone repair and growth stimulations, blood stimulations, endocrine functioning, and nervous system functioning. These studies involve an exposure to low-frequency currents or fields on the human body. At extremely low frequencies, an individual is able to perceive electric field presence through stimulation of pressure sensors or vibration (McRee & Wachtel, 1982). However, in brain evoked potentials, the effects of bioelectromagnetic fields have been observed when the subject was exposed to both intermittent and continuous fields of 20µT and 9kVm-1. As such, a reversal of polarity and a reduction in the amplitude of the three key potentials led to changes in visually evoked potentials.
Principle of Reciprocity as Applied in Bioelectromagnetism
This is the principle that holds for all linear systems whereby swapping of measurement and source sites is done without changes in the detected signal. The reciprocity principle holds that the results of the impedance measurement should remain the same upon swapping of the current feeding and voltage measurement, which makes the measurement region get closer to the electrode pairs. However, the sensitivity of the measurement is not necessarily limited to the accurately bounded region although the signal must be affected by the volume conductor regions (Valdmanis & Cipijs, 2008). There thus are distributions of the measurement sensitivity in electrode configurations of adaptive methods. Reciprocity follows the concepts of positive and negative sensitivity whereby the negative sensitivity seems to complicate the impedance signal analysis.
In the case of positive sensitivity, an increase in the impedance of a region leads to an increase in the impedance signal. Conversely, in negative sensitivity, as the impedance of a region increases, the signal decreases (Starzynski et al., 2009). Therefore, as the lead fields and their components are in the same direction, then the sensitivity is positive while a move in an opposite direction means the sensitivity is negative. These instances are well noted in various impedance cardiograph leads whereby a blue color is an indication of a negative sensitivity while the positive sensitivity is shown by the red color. One of the applications of this principle is the tomography with x-rays whereby the resolution is excellent since the amplitude of the signal is dependent on the material density on the straight line of the x-ray beams relayed between the source and detector (Malmivuo & Plonsey, 1995).
Further, reciprocity assists scientist and medics to solve bioelectromagnetism problems through an understanding of the measurement sensitivity as well as the distribution problems in stimulus intensity. Reciprocity determines the accuracy of the back-projections in x-ray experiments and tomography, which could be increased through the process of increasing the number of electrodes to lower the distance covered (Cheng, 1992). The distribution of the measurement sensitivity and stimulus intensity can be demonstrated by feeding of unit current to the measurement electrodes to raise the volume conductor’s current distribution, usually called the lead field. The lead field denotes the distribution of stimulus current and as the distributions of stimulus current and measurement sensitivity for the two electrodes become identical.
The principle of reciprocity is also true for the reciprocal situation whereby the reciprocal current is fed to the source dipole with the signal being detected using a squid magnetometer. As such, the reciprocal current fed to the coil represents the measurement results measured as well as the signals detected using the volume conductor electrodes. However, biomagnetism presents a problem whether the magnetic measurements encompasses information which is independent of the electric measurements. Therefore, with the magnetic measurement, one can obtain crucial information that can otherwise be obtained using electric sources (Starzynski et al., 2009). However, the lead field theory disputes this claim and provides information through a demonstration that magnetic and electric lead fields are independent although the measured signals are partially independent.
The functioning of the bioelectromagnetism involves an electric activity of the body tissue whereby an electric potential field is created. The electric current created in the volume conductor prompts a magnetic field, which means that there exists a magnetic material in the body which leads to the magnetic field. As such, the electric current feeding to the human body produces stimulation which in turn excites the nerve and muscle tissue. Conversely, stimulation current is also prompted through an application of an alternating magnetic field to it with the magnetic field being applied to magnetize the magnetic material in the human body (Starzynski et al., 2009).
Another subdivision of bioelectromagnetism involves the measurement of the intrinsic magnetic and electric properties of the body tissues. This can be ascertained through the feeding of the volume conductor with subthreshold electric current and thus measuring the voltage produced thereof to the tissue impedance. Alternatively, this can be measured through an application of the magnetic field to the human body. Moreover, attenuation is measured by measuring the magnetic susceptibility of a material.
Other Applications of Bioelectromagnetism
The magnetic stimulation is applied to nervous stimulation either peripherally or centrally. The stimulation is usually equally distributed within the tissue rather than the concentration at the skin. As a result, the magnetic stimulation of the skin does not produce any painful sensation. Moreover, the use of magnetic stimulation is useful, especially when surgeons are performing a sterile operation since the stimulator does not entail direct skin contact. However, more studies have shown that it would be easier to perform magnetic stimulation to the cortical areas due to the difficulty involved in producing concentrated stimulating current density distributions while avoiding high current densities on an individual’s scalp (Malmivuo & Plonsey, 1995).
Bioelectromagnetism is also applied in the magnetic and electric stimulation of the heart with the clinical applications being cardiac defibrillation and cardiac pacing. Cardiac defibrillation is used in the stopping of the uncontrolled and continuous multiple re-entrant activation circuits that lead to fibrillating contractions of muscles. Such fibrillation of the muscles is responsible for the total weakening of the blood pumping action thereby occasioning inadequacy of oxygen in the brain tissue, decreased blood pressure, and eventually death unless fibrillation from the patient can be immediately stopped. Cardiac pacing, on the other hand, functions to maintain a sufficient heart rate level although the sinus node activity may fail to reach the ventricular muscle due to conduction system interruption. This happens during instances when the blood pressure is too low to keep the body sustained with enough oxygen due to lower heart rate. Bioelectromagnetism is thus used to achieve both cardiac defibrillation and cardiac pacing through a process of magnetic stimulation.
Bioelectromagnetic signals emanate from the excitable tissues of the body, particularly, the muscle and nerve cells, for instance, the electro oculogram, which is produced by the eye’s electric polarization of the static energy. These electric potential are capable of measurement around the eye albeit magnetically. The electro oculogram involves a production of bioelectric signals by the excitable tissues in the eye. Moreover, the electric response to light by the retina is referred to as electroretinogram. This involves a movement of physical information from the retina to the central nervous system using the optic nerve. However, the bioelectric signals comprise an excitable nervous tissue.
With regard to magneto cardiology, the mapping method is used to determine the equivalent magnetic dipole. However, localization of cardiac sources is used analyze the parameters of MCG signals whereby localization of cardiac abnormalities is allowed to take place and thus causing the fatal arrhythmias or even a decrease in the cardiac performance. The abnormal conduction pathways are useful in conducting an electric activity to the ventricular muscle from the atrial muscle thereby occasioning the Wolff-Parkinson-White or syndrome (Malmivuo & Plonsey, 1995). In magnetocardiography, doctors work to introduce an alternative to the electric localization with the help of magnetic methods whereby mapping of the cardiac magnetic field x-component is done on the anterior surface of the thorax with the help of both multichannel and single-channel magnetometer.
The effects of bioelectromagnetism phenomena on the human body can be explained by the production of an electromagnetic field in the brain and nervous system. This is created by the billions of nerve impulse present throughout the body, which creates complex human magnetic fields on a constant basis. The human electromagnetic wave is detectable from a distance using the modern scientific instruments and as such, the wave is capable of influencing other people who are standing by the individual, for instance, being close to some people may make one more energized and optimistic as opposed to being close to other people. Further, the human body is capable of producing electric energy waves in the form of infra-red radiation.
The human body is wired to operate on bioelectricity with organs dedicated to bioelectromagnetic functions. These organs include the pituitary and pineal glands, which allow the body to sense and experience electromagnetic impulses both outside and inside the body. The pineal gland is responsible for regulating the biological rhythms of the day and night cycle as well as the body’s circadian rhythms. The pituitary gland, on the other hand, controls and influences all the other hormonal organs. The pituitary gland is responsible for the efficiency and functioning of the human nervous system, which is based on electric pulse transmission as well as the sodium-potassium pump through the adenosine triphosphate, which manipulates the electromagnetic fields that are sent back to the universe (Malmivuo & Plonsey, 1995).
Exposure to simple high voltage electrostatic fields has been found to affect the human body in a number of favorable ways. High voltage fields emitted in 2400kVm-1 are beneficial to liver respiration as well as the formation of antibodies. This implies the high voltage electrostatic fields may play a beneficial role in the immune system. These fields, when emitted in exogenous MHz range, could be useful in bone repair, especially for patients with osteoarthritis. Moreover, pulsed magnetic or electric fields have been useful in boosting macromolecule synthesis, for instance, collagen or DNA, which are responsible for the formation of connective tissue. However, scientists have found that interruption of the field by 1 Hz causes the DNA synthesis to go up by 20 percent while collagen synthesis rises by 100 percent.
Future Research in Bioelectromagnetism
There has been a segmented overall research strategy on bioelectromagnetism amid the extensive base of literature with regard to the medical applications of bioelectric magnetism. Therefore, an integrated research program is needed to provide details on the potential for treatment of different medical conditions through clinical research in bioelectromagnetism. This should incorporate both basic and clinical research in a simultaneous and vigorous manner along the same path. As such, basic research would be crucial in the refinement and development of bioelectricmagnetism and its technologies with a goal to establish the basic knowledge on the endogenous electromagnetic fields as well as their interaction with clinically applied electromagnetic fields (Cheng, 1992).
An understanding of the bioelectromagnetic functioning of the human body would be essential in providing an insight as to the scientific bio-informational principles through which alternative medicine fields, such as homeopathy and acupuncture would function. Additionally, an in-depth knowledge of the functioning of body bioelectromagnetism and the psychophysiological states would be necessary for the understanding of the regulation of the human mind and body. Further, further clinical research would help in the realization of advanced bioelectromagnetic treatments and diagnosis within a short period of time (Starzynski et al., 2009). However, these devices must be thoroughly tested before they can be rolled out for therapeutic use and to ascertain for their safety.
Bioelectromagnetism has assisted in the furthering of studies on energy radiation for the treatment of diseases, such as cancer using electromagnetic fields although some fields are hazardous to the human body. This has sparked interest in low-intensity non-thermal electromagnetic fields. As such, bioelectromagnetism applications have been crucial in providing effective and more economical diagnostics as well as non-invasive therapies for various medical problems which have resisted conventional treatment methods. Further, bioelectricmagnetism has also increased the body of knowledge on the basic mechanisms of regulation and communication at different levels, such as organismic and intracellular.
This has increased the advances scientists are making on breakthroughs in diagnostic and treatment methods. With regard to other medical procedures, bioelectricmagnetism allows scientists the conceptual framework of various therapeutic and diagnostic techniques, such as homeopathy and acupuncture. The principle of reciprocity, however crucial to the field of bioelectromagnetism has not been generally applied. However, in most problems reciprocity provides more illustrative and faster solution once the direct method is applied. By applying the principle of reciprocity, the calculations in multichannel problems are reduced drastically, for instance, in cortical potential imaging whereby the calculations decrease from 100,000 to 250.
Therefore, the bioelectric phenomena will remain a crucial part of the diagnostic and therapeutic field of medicine. The devices made from these studies are fast and non-invasive and as such produce no side effects to the patients who use them. Moreover, the biomagnetic techniques applied, provide an extension to the bioelectric phenomena through an addition of traditional sensitivity as well as energy distribution for more diagnostic performances. Thus by comprehending the principle of reciprocity and the Maxwell’s Equation provides researchers and medical practitioners with a grasp of the designing of improved techniques and methods that can further the field of bioelectromagnetism for diagnosis and therapeutic purposes.