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Detailed magnetoelectric analysis of a nerve impulse propagation along the brachial plexus. Clin Neurophysiol 2023; 145:129-138. [PMID: 36280574 DOI: 10.1016/j.clinph.2022.09.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 09/02/2022] [Accepted: 09/25/2022] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To visualize impulse conduction along the brachial plexus through simultaneous electromagnetic measurements. METHODS Neuromagnetic fields following median nerve stimulation were recorded above the clavicle with a superconducting quantum interference device biomagnetometer system in 7 healthy volunteers. Compound nerve action potentials (CNAPs) were obtained from 12 locations. Pseudocolor maps of equivalent currents reconstructed from magnetic fields and isopotential contour maps were superimposed onto X-ray images. Surface potentials and current waveforms at virtual electrodes along the brachial plexus were compared. RESULTS In magnetic field analysis, the leading axonal current followed by a trailing backward current traveled rostrally along the brachial plexus. The spatial extent of the longitudinal intra-axonal currents corresponded to the extent of the positive-negative-positive potential field reflecting transmembrane volume currents. The peaks and troughs of the intra-axonal biphasic current waveforms coincided with the zero-crossings of triphasic CNAP waveforms. The amplitudes of CNAPs and current moments were linearly correlated. CONCLUSIONS Reconstructed neural activity in magnetic field analysis visualizes not only intra-axonal currents, but also transmembrane volume currents, which are in good agreement with the surface potential field. SIGNIFICANCE Magnetoneurography is a novel non-invasive functional imaging modality for the brachial plexus whose performance can surpass that of electric potential measurement.
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Hashimoto J, Kawabata S, Sasaki T, Hoshino Y, Sekihara K, Adachi Y, Watanabe T, Miyano Y, Mitani Y, Sato S, Kim S, Yoshii T, Okawa A. Assessment of thoracic spinal cord electrophysiological activity through magnetoneurography. Clin Neurophysiol 2021; 133:39-47. [PMID: 34800837 DOI: 10.1016/j.clinph.2021.09.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 09/09/2021] [Accepted: 09/30/2021] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Noninvasive and detailed visualization of electrophysiological activity in the thoracic spinal cord through magnetoneurography. METHODS In five healthy volunteers, magnetic fields around current flowing in the thoracic spinal cord after alternating unilateral and synchronized bilateral sciatic nerve stimulation were measured using a magnetoneurograph system with superconductive quantum interference device biomagnetometers. The current distribution was obtained from the magnetic data by spatial filtering and visualized by superimposing it on the X-ray image. Conduction velocity was calculated using the peak latency of the current waveforms. RESULTS A sufficiently high magnetic signal intensity and signal-to-noise ratio were obtained in all participants after synchronized bilateral sciatic nerve stimulation. Leading and trailing components along the spinal canal and inward components flowing into the depolarization site ascended to the upper thoracic spine. Conduction velocity of the inward current in the whole thoracic spine was 42.4 m/s. CONCLUSIONS Visualization of electrophysiological activity in the thoracic spinal cord was achieved through magnetoneurography and a new method for synchronized bilateral sciatic nerve stimulation. Magnetoneurography is expected to be a useful modality in functional assessment of thoracic myelopathy. SIGNIFICANCE This is the first report to use magnetoneurography to noninvasively visualize electrophysiological activity in the thoracic spinal cord in detail.
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Affiliation(s)
- Jun Hashimoto
- Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Shigenori Kawabata
- Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan; Department of Advanced Technology in Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Toru Sasaki
- Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Yuko Hoshino
- Department of Advanced Technology in Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Kensuke Sekihara
- Department of Advanced Technology in Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Yoshiaki Adachi
- Applied Electronics Laboratory, Kanazawa Institute of Technology, 3 Amaike-cho, Kanazawa City, Ishikawa 920-1331, Japan.
| | - Taishi Watanabe
- RICOH Company, Ltd., 1-3-6 Nakamagome, Ohta-ku, Tokyo 143-8555, Japan.
| | - Yuki Miyano
- RICOH Company, Ltd., 1-3-6 Nakamagome, Ohta-ku, Tokyo 143-8555, Japan.
| | - Yuki Mitani
- RICOH Company, Ltd., 1-3-6 Nakamagome, Ohta-ku, Tokyo 143-8555, Japan.
| | - Shinji Sato
- RICOH Company, Ltd., 1-3-6 Nakamagome, Ohta-ku, Tokyo 143-8555, Japan.
| | - Sukchan Kim
- RICOH Company, Ltd., 1-3-6 Nakamagome, Ohta-ku, Tokyo 143-8555, Japan.
| | - Toshitaka Yoshii
- Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Atsushi Okawa
- Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
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Evaluation of neural activity by magnetospinography with 3D sensors. Clin Neurophysiol 2020; 131:1252-1266. [PMID: 32299009 DOI: 10.1016/j.clinph.2020.02.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 01/10/2020] [Accepted: 02/15/2020] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Magnetospinography (MSG) has been developed for clinical application and is expected to be a novel neurophysiological examination. Here, we used an MSG system with sensors positioned in three orthogonal directions to record lumbar canal evoked magnetic fields (LCEFs) in response to peripheral nerve stimulation and to evaluate methods for localizing spinal cord lesions. METHODS LCEFs from the lumbar area of seven rabbits were recorded by the MSG system in response to electrical stimulation of a sciatic nerve. LCEFs and lumbar canal evoked potentials (LCEPs) were measured before and after spinal cord compression induced by a balloon catheter. The lesion positions were estimated using LCEPs and computationally reconstructed currents corresponding to the depolarization site. RESULTS LCEFs were recorded in all rabbits and neural activity in the lumbar spinal cord could be visualized in the form of a magnetic contour map and reconstructed current map. The position of the spinal cord lesion could be estimated by the LCEPs and reconstructed currents at the depolarization site. CONCLUSIONS MSG can visualize neural activity in the spinal cord and localize the lesion site. SIGNIFICANCE MSG enables noninvasive assessment of neural activity in the spinal canal using currents at depolarization sites reconstructed from LCEFs.
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Sharma S, Vijay S, Gore S, Dore TM, Jagannathan R. Measuring Cellular Ion Transport by Magnetoencephalography. ACS OMEGA 2020; 5:4024-4031. [PMID: 32149229 PMCID: PMC7057328 DOI: 10.1021/acsomega.9b03589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/05/2020] [Indexed: 06/10/2023]
Abstract
The cellular-level process of ion transport is known to generate a magnetic field. A noninvasive magnetoencephalography (MEG) technique was used to measure the magnetic field emanating from HeLa, HEK293, and H9c2(2-1) rat cardiac cells. The addition of a nonlethal dose of ionomycin to HeLa and capsaicin to TRPV1-expressing HEK293 cells resulted in a sudden change in the magnetic field signal consistent with Ca2+ influx, which was also observed by confocal fluorescence microscopy under the same conditions. In contrast, addition of capsaicin to TRPV1-expressing HEK293 cells containing an optimum amount of a TRPV1 antagonist (ruthenium red), resulted in no detectable magnetic or fluorescent signals. These signals confirmed that the measured MEG signals are due to cellular ion transport through the cell membrane. In general, there is evidence that ion channel/transporter activation and ionic flux are linked to cancer. Therefore, our work suggests that MEG could represent a noninvasive method for detecting cancer.
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Affiliation(s)
- Sudhir
Kumar Sharma
- Engineering
Division, New York University Abu Dhabi, PO Box 129188, Abu Dhabi, UAE
| | - Sauparnika Vijay
- Science
Division, New York University Abu Dhabi, PO Box 129188, Abu Dhabi, UAE
| | - Sangram Gore
- Science
Division, New York University Abu Dhabi, PO Box 129188, Abu Dhabi, UAE
| | - Timothy M. Dore
- Science
Division, New York University Abu Dhabi, PO Box 129188, Abu Dhabi, UAE
- Department
of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Ramesh Jagannathan
- Engineering
Division, New York University Abu Dhabi, PO Box 129188, Abu Dhabi, UAE
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Abstract
Historically, the activity of muscle groups has been evaluated indirectly, through strength and range of movement measurements. While direct evaluation of muscle activity has been achieved using surface or invasive electrodes, the latter methodologies are limited to individual muscles. By contrast, magnetic recording of muscle activity, as illustrated here, offers a noninvasive approach to evaluate the activity of large muscle groups. This includes deep structures such as the heart and intraabdominal musculature such as the iliacus muscle. An unexpected finding was the ability to image activity associated with muscle pain. Thus, this method offers a noninvasive biomarker for muscular pain and, significantly, of neck and back pain, which now relies mainly on the patient’s report of signs and symptoms. A spectroscopic paradigm has been developed that allows the magnetic field emissions generated by the electrical activity in the human body to be imaged in real time. The growing significance of imaging modalities in biology is evident by the almost exponential increase of their use in research, from the molecular to the ecological level. The method of analysis described here allows totally noninvasive imaging of muscular activity (heart, somatic musculature). Such imaging can be obtained without additional methodological steps such as the use of contrast media.
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Novel functional imaging technique for the brachial plexus based on magnetoneurography. Clin Neurophysiol 2019; 130:2114-2123. [PMID: 31542709 DOI: 10.1016/j.clinph.2019.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 08/02/2019] [Accepted: 08/12/2019] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To visualize neural activity in the brachial plexus using magnetoneurography (MNG). METHODS Using a 124- or 132-channel biomagnetometer system with a superconducting quantum interference device, neuromagnetic fields above the clavicle and neck region were recorded in response to electrical stimulation of the median and ulnar nerves in five asymptomatic volunteers (four men and one woman; age, 27-45 years old). Equivalent currents were computationally reconstructed from neuromagnetic fields and visualized as pseudocolor maps. Reconstructed currents at the depolarization site and compound nerve action potentials (CNAPs) at Erb's point were compared. RESULTS Neuromagnetic fields were recorded in all subjects. The reconstructed equivalent currents propagated into the vertebral foramina, and the main inflow levels differed between the median nerve (C5/C6-C7/T1 vertebral foramen) and the ulnar nerve (C7/T1-T1/T2). The inward current peaks at the depolarization site and CNAPs showed high linear correlation. CONCLUSIONS MNG visualizes neural activity in the brachial plexus and can differentiate the conduction pathways after median and ulnar nerve stimulations. In addition, it can visualize not only the leading and trailing components of intra-axonal currents, but also inward currents at the depolarization site. SIGNIFICANCE MNG is a novel and promising functional imaging modality for the brachial plexus.
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Ushio S, Hoshino Y, Kawabata S, Adachi Y, Sekihara K, Sumiya S, Ukegawa D, Sakaki K, Watanabe T, Hasegawa Y, Okawa A. Visualization of the electrical activity of the cauda equina using a magnetospinography system in healthy subjects. Clin Neurophysiol 2018; 130:1-11. [PMID: 30471467 DOI: 10.1016/j.clinph.2018.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 10/24/2018] [Accepted: 11/02/2018] [Indexed: 01/12/2023]
Abstract
OBJECTIVE To establish a method to measure cauda equina action fields (CEAFs) and visualize the electrical activities of the cauda equina in a broadly aged group of healthy adults. METHODS Using a 124-channel magnetospinography (MSG) system with superconducting interference devices, the CEAFs of 43 healthy volunteers (22-64 years of age) were measured after stimulation of the peroneal nerve at the knee. Reconstructed currents were obtained from the CEAFs and superimposed on the X-ray image. Conduction velocities were also calculated from the waveform of the reconstructed currents. RESULTS The reconstructed currents were successfully visualized. They flowed into the L5/S1 foramen about 8.25-8.95 ms after the stimulation and propagated cranially along the spinal canal. In 32 subjects (74%), the conduction velocities of the reconstructed currents in the cauda equina could be calculated from the peak latency at the L2-L5 level. CONCLUSIONS MSG visualized the electrical activity of the cauda equina after peroneal nerve stimulation in healthy adults. In addition, the conduction velocities of the reconstructed currents in the cauda equina could be calculated, despite previously being difficult to measure. SIGNIFICANCE MSG has the potential to be a novel and noninvasive functional examination for lumbar spinal disease.
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Affiliation(s)
- Shuta Ushio
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Yuko Hoshino
- Department of Advanced Technology in Medicine, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Shigenori Kawabata
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan; Department of Advanced Technology in Medicine, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Yoshiaki Adachi
- Applied Electronics Laboratory, Kanazawa Institute of Technology, Kanazawa-shi, Ishikawa 920-1331, Japan
| | - Kensuke Sekihara
- Department of Advanced Technology in Medicine, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Satoshi Sumiya
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Dai Ukegawa
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Kyohei Sakaki
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Taishi Watanabe
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan; RICOH Company, Ltd., 16-1 Shinei-cho, Tsuzuki-ku, Yokohama, Kanagawa 224-0035, Japan
| | - Yuki Hasegawa
- Department of Advanced Technology in Medicine, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Atsushi Okawa
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
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Manzo LP, Ceragioli H, Bonet IJ, Nishijima CM, Vieira WF, Oliveira EC, Destro-Filho JB, Sartori CR, Tambeli CH, Parada CA. Magnetic, but not non-magnetic, reduced graphene oxide in spinal cord increases nociceptive neuronal responsiveness. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2017; 13:1841-1851. [DOI: 10.1016/j.nano.2017.02.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 01/31/2017] [Accepted: 02/27/2017] [Indexed: 12/25/2022]
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Sumiya S, Kawabata S, Hoshino Y, Adachi Y, Sekihara K, Tomizawa S, Tomori M, Ishii S, Sakaki K, Ukegawa D, Ushio S, Watanabe T, Okawa A. Magnetospinography visualizes electrophysiological activity in the cervical spinal cord. Sci Rep 2017; 7:2192. [PMID: 28526877 PMCID: PMC5438392 DOI: 10.1038/s41598-017-02406-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 04/11/2017] [Indexed: 11/09/2022] Open
Abstract
Diagnosis of nervous system disease is greatly aided by functional assessments and imaging techniques that localize neural activity abnormalities. Electrophysiological methods are helpful but often insufficient to locate neural lesions precisely. One proposed noninvasive alternative is magnetoneurography (MNG); we have developed MNG of the spinal cord (magnetospinography, MSG). Using a 120-channel superconducting quantum interference device biomagnetometer system in a magnetically shielded room, cervical spinal cord evoked magnetic fields (SCEFs) were recorded after stimulation of the lower thoracic cord in healthy subjects and a patient with cervical spondylotic myelopathy and after median nerve stimulation in healthy subjects. Electrophysiological activities in the spinal cord were reconstructed from SCEFs and visualized by a spatial filter, a recursive null-steering beamformer. Here, we show for the first time that MSG with high spatial and temporal resolution can be used to map electrophysiological activities in the cervical spinal cord and spinal nerve.
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Affiliation(s)
- Satoshi Sumiya
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Shigenori Kawabata
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan. .,Department of Advanced Technology in Medicine, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
| | - Yuko Hoshino
- Department of Advanced Technology in Medicine, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Yoshiaki Adachi
- Applied Electronics Laboratory, Kanazawa Institute of Technology, Kanazawa-shi, Ishikawa, 920-1331, Japan
| | - Kensuke Sekihara
- Department of Advanced Technology in Medicine, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Shoji Tomizawa
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Masaki Tomori
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Senichi Ishii
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Kyohei Sakaki
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Dai Ukegawa
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Shuta Ushio
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Taishi Watanabe
- Ricoh Institute of Future Technology, RICOH COMPANY, LTD., 16-1 Shinei-cho, Tsuzuki-ku, Yokohama-shi, Kanagawa, 224-0034, Japan
| | - Atsushi Okawa
- Department of Orthopaedic Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
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Goodman G, Bercovich D. Electromagnetic induction between axons and their schwann cell myelin-protein sheaths. J Integr Neurosci 2014; 12:475-89. [PMID: 24372067 DOI: 10.1142/s0219635213500295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Two concepts have long dominated vertebrate nerve electrophysiology: (a) Schwann cell-formed myelin sheaths separated by minute non-myelinated nodal gaps and spiraling around axons of peripheral motor nerves reduce current leakage during propagation of trains of axon action potentials; (b) "jumping" by action potentials between successive nodes greatly increases signal conduction velocity. Long-held and more recent assumptions and issues underlying those concepts have been obscured by research emphasis on axon-sheath biochemical symbiosis and nerve regeneration. We hypothesize: mutual electromagnetic induction in the axon-glial sheath association, is fundamental in signal conduction in peripheral and central myelinated axons, explains the g-ratio and is relevant to animal navigation.
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Affiliation(s)
- G Goodman
- Galil Genetic Analysis, Kazerin 12900, Israel
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11
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Abstract
BACKGROUND The establishment of reliable methods for functional assessment in experimental models of peripheral nerve regeneration is crucial. METHODS We present a straightforward method for video analysis of the eye blink reflex in a model of facial nerve damage in a nonhuman primate (Callithrix sp.). RESULTS Our 6-level dynamic analysis demonstrated good reproducibility between independent observers, as measured by Cohen's kappa index. Our static analysis, which was based on 4 semiautomated metric parameters, showed low correlation during the early stage of facial movement recovery (the first and second weeks), but the correlation was excellent during the later stage of recovery (the third and fourth weeks). CONCLUSION Altogether, our results establish a viable and readily accessible method with good reproducibility and correlation for the analysis of functional facial nerve recovery in an experimental model and based on video images of the eye blink reflex.
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Comlekci S, Coskun O. Influence of 50 Hz-1 mT magnetic field on human median nerve. Electromagn Biol Med 2012; 31:285-92. [DOI: 10.3109/15368378.2012.662190] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Selcuk Comlekci
- Department of Electronics and Communication Engineering, Suleyman Demirel University
Isparta, Turkey
| | - Ozlem Coskun
- Department of Electronics and Communication Engineering, Suleyman Demirel University
Isparta, Turkey
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