{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T05:19:08Z","timestamp":1787635148418,"version":"build-2736575974"},"reference-count":52,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T00:00:00Z","timestamp":1787270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["12204273"],"award-info":[{"award-number":["12204273"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["12204273"],"award-info":[{"award-number":["12204273"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012905","name":"Department of Science and Technology of Shandong Province","doi-asserted-by":"publisher","award":["ZR2024MF107"],"award-info":[{"award-number":["ZR2024MF107"]}],"id":[{"id":"10.13039\/100012905","id-type":"DOI","asserted-by":"publisher"}]},{"award":["ZR2024MF107"],"award-info":[{"award-number":["ZR2024MF107"]}],"id":[{"id":"https:\/\/ror.org\/01b9fvd84","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Addressing the current issues of the uncertain primary frequency bands and the difficulty in directly measuring the spectral characteristics of neural electromagnetic signals transmitted within nerve fibers, this study investigates the spectral and time-domain properties of the neural electromagnetic signals through finite element simulations, using the influence of the node of Ranvier on nerve conduction velocity as a breakthrough point, and develops a coaxial transmission line impedance transformation model. The research results demonstrate that the primary signals capable of effective transmission within nerve fibers may reside in the terahertz (THz) band. They also show that the node of Ranvier essentially functions by regulating its geometric length to achieve impedance matching between the node and the myelin sheath, thereby reaching the optimal efficiency for signal coupling. The above finding not only explains the mechanism underlying the non-monotonic variation in neural conduction velocity with the length of the node of Ranvier, but also provides the latest perspective for understanding the relationship and differences between transmembrane action potentials that accompany the generation of neural signals and information transmission carriers\u2014electromagnetic signals. It may also provide a theoretical supplement to the understanding of signal frequency\u2013timing issues in neural encoding.<\/jats:p>","DOI":"10.3390\/bioengineering13080955","type":"journal-article","created":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T15:51:05Z","timestamp":1787327465000},"page":"955","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Simulation of Neural Signals\u2019 Spectrum and Transmission from the Perspective of Impedance-Matching Effect of the Ranvier Node"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-7690-2144","authenticated-orcid":false,"given":"Mingwei","family":"Song","sequence":"first","affiliation":[{"name":"School of Integrated Circuits, Shandong University, Jinan 250101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhiming","family":"Xu","sequence":"additional","affiliation":[{"name":"Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing 100871, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0443-547X","authenticated-orcid":false,"given":"Jingjing","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Integrated Circuits, Shandong University, Jinan 250101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,21]]},"reference":[{"key":"ref_1","unstructured":"Kandel, E.R., Koester, J.D., Mack, S.H., and Siegelbaum, S.A. (2021). Principles of Neural Science, McGraw Hill LLC. [6th ed.]."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1113\/jphysiol.1952.sp004764","article-title":"A Quantitative Description of Membrane Current and Its Application to Conduction and Excitation in Nerve","volume":"117","author":"Hodgkin","year":"1952","journal-title":"J. Physiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"315","DOI":"10.1113\/jphysiol.1949.sp004335","article-title":"Evidence for Saltatory Conduction in Peripheral Myelinated Nerve Fibres","volume":"108","author":"Huxley","year":"1949","journal-title":"J. Physiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1007\/s00249-012-0787-7","article-title":"Extracellular electrical signals in a neuron-surface junction: Model of heterogeneous membrane conductivity","volume":"41","author":"Bulai","year":"2012","journal-title":"Eur. Biophys. J."},{"key":"ref_5","first-page":"031047","article-title":"Penetration of Action Potentials During Collision in the Median and Lateral Giant Axons of Invertebrates","volume":"4","author":"Budvytyte","year":"2014","journal-title":"Phys. Rev. X"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1007\/BF00619355","article-title":"Waveform Generation of the Electric Organ Discharge in Gymnotus-Carapo. 3. Analysis of the Fish Body as an Electric Source","volume":"165","author":"Caputi","year":"1989","journal-title":"J. Comp. Physiol. A"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1007\/BF00619354","article-title":"Waveform Generation of the Electric Organ Discharge in Gymnotus-Carapo. 2. Electrophysiological Properties of Single Electrocytes","volume":"165","author":"Macadar","year":"1989","journal-title":"J. Comp. Physiol. A"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1231","DOI":"10.1126\/science.1260807","article-title":"The shocking predatory strike of the electric eel","volume":"346","author":"Catania","year":"2014","journal-title":"Science"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"9790","DOI":"10.1073\/pnas.0503823102","article-title":"On soliton propagation in biomembranes and nerves","volume":"102","author":"Heimburg","year":"2005","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"4327","DOI":"10.1007\/s12648-025-03609-w","article-title":"Periodic pressure waves and transmembrane wavefronts in an electromechanical nerve model","volume":"99","author":"Nfor","year":"2025","journal-title":"Indian J. Phys."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/j.plrev.2013.08.002","article-title":"Consciousness in the universe: A review of the \u2018Orch OR\u2019 theory","volume":"11","author":"Hameroff","year":"2014","journal-title":"Phys. Life Rev."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Keppler, J. (2025). Macroscopic quantum effects in the brain: New insights into the fundamental principle underlying conscious processes. Front. Hum. Neurosci., 19.","DOI":"10.3389\/fnhum.2025.1676585"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1219","DOI":"10.1007\/s12274-019-2281-3","article-title":"Quantum-confined ion superfluid in nerve signal transmission","volume":"12","author":"Zhang","year":"2019","journal-title":"Nano Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1029","DOI":"10.1039\/C9NH00214F","article-title":"Quantum-confined superfluid","volume":"4","author":"Hao","year":"2019","journal-title":"Nanoscale Horiz."},{"key":"ref_15","unstructured":"Xue, J., and Xu, S. (2012). Natural electromagnetic waveguide structures based on myelin sheath in the neural system. arXiv."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"230","DOI":"10.2174\/2213385205666170127142624","article-title":"The roles of membrane for electrical communication in a biosystem","volume":"4","author":"Xu","year":"2016","journal-title":"Neurosci. Biomed. Eng. Discontin."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1016\/j.bbrc.2018.01.118","article-title":"Phenomena of synchronized response in biosystems and the possible mechanism","volume":"496","author":"Xu","year":"2018","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"13824","DOI":"10.1038\/s41598-018-32345-x","article-title":"Experimental and Computational Studies on the Basic Transmission Properties of Electromagnetic Waves in Softmaterial Waveguides","volume":"8","author":"Xu","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1038\/s41598-017-18866-x","article-title":"Node of Ranvier as an Array of Bio-Nanoantennas for Infrared Communication in Nerve Tissue","volume":"8","author":"Zangari","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1807862","DOI":"10.1002\/adfm.201807862","article-title":"Myelin Sheath as a Dielectric Waveguide for Signal Propagation in the Mid-Infrared to Terahertz Spectral Range","volume":"29","author":"Liu","year":"2019","journal-title":"Adv. Funct. Mater."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"590","DOI":"10.1007\/s12274-020-3016-1","article-title":"A new viewpoint and model of neural signal generation and transmission: Signal transmission on unmyelinated neurons","volume":"14","author":"Xiang","year":"2021","journal-title":"Nano Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1016\/j.scib.2019.12.004","article-title":"A primary model of THz and far-infrared signal generation and conduction in neuron systems based on the hypothesis of the ordered phase of water molecules on the neuron surface I: Signal characteristics","volume":"65","author":"Xiang","year":"2020","journal-title":"Sci. Bull."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"038701","DOI":"10.1088\/1674-1056\/ac1e1a","article-title":"Long range electromagnetic field nature of nerve signal propagation in myelinated axons","volume":"31","author":"Zhai","year":"2022","journal-title":"Chin. Phys. B"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"108701","DOI":"10.1088\/1674-1056\/abaee9","article-title":"A new viewpoint and model of neural signal generation and transmission: Signal transmission on myelinated neuron","volume":"29","author":"Xiang","year":"2020","journal-title":"Chin. Phys. B"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"20720","DOI":"10.1038\/s41598-022-24871-6","article-title":"Photons guided by axons may enable backpropagation-based learning in the brain","volume":"12","author":"Zarkeshian","year":"2022","journal-title":"Sci. Rep."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"613","DOI":"10.1109\/TMBMC.2024.3464415","article-title":"Optical Polarization Evolution and Transmission in Multi-Ranvier-Node Axonal Myelin-Sheath Waveguides","volume":"10","author":"Frede","year":"2024","journal-title":"IEEE Trans. Mol. Biol. Multi-Scale Commun."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"10380","DOI":"10.1364\/AO.574928","article-title":"Loss-amplification-radiation coupling model of the mid-infrared signal propagating in demyelinated axons","volume":"64","author":"Zhang","year":"2025","journal-title":"Appl. Opt."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/j.cjph.2025.11.017","article-title":"Biophysical exploration of the neural soft-matter waveguide propagation hypothesis","volume":"99","author":"Xu","year":"2026","journal-title":"Chin. J. Phys."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"068701","DOI":"10.1088\/1674-1056\/ac3cac","article-title":"Simulation of the physical process of neural electromagnetic signal generation based on a simple but functional bionic Na channel","volume":"31","author":"Wang","year":"2022","journal-title":"Chin. Phys. B"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"36508","DOI":"10.1038\/srep36508","article-title":"Possible existence of optical communication channels in the brain","volume":"6","author":"Kumar","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"e23329","DOI":"10.7554\/eLife.23329","article-title":"Node of Ranvier length as a potential regulator of myelinated axon conduction speed","volume":"6","author":"Ford","year":"2017","journal-title":"eLife"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"8073","DOI":"10.1038\/ncomms9073","article-title":"Tuning of Ranvier node and internode properties in myelinated axons to adjust action potential timing","volume":"6","author":"Ford","year":"2015","journal-title":"Nat. Commun."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1016\/j.neulet.2017.08.037","article-title":"What is the optimal distribution of myelin along a single axon?","volume":"658","author":"Walsh","year":"2017","journal-title":"Neurosci. Lett."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1785","DOI":"10.1137\/22M1544063","article-title":"A PML Method for Signal-Propagation Problems in Axon","volume":"83","author":"Jiang","year":"2023","journal-title":"SIAM J. Appl. Math."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Nobue, A., and Ishikawa, M. (2024). Sex-Specific Differences in Peripheral Nerve Properties: A Comparative Analysis of Conduction Velocity and Cross-Sectional Area in Upper and Lower Limbs. Diagnostics, 14.","DOI":"10.3390\/diagnostics14232711"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"028701","DOI":"10.1088\/1674-1056\/abc0d2","article-title":"An electromagnetic view of relay time in propagation of neural signals","volume":"30","author":"Xu","year":"2021","journal-title":"Chin. Phys. B"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1093\/jnen\/nlx014","article-title":"The Significance of Internode Length for Saltatory Conduction: Looking Back at the Age of 90","volume":"76","author":"Friede","year":"2017","journal-title":"J. Neuropathol. Exp. Neurol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1016\/j.tins.2008.04.001","article-title":"White matter in learning, cognition and psychiatric disorders","volume":"31","author":"Fields","year":"2008","journal-title":"Trends Neurosci."},{"key":"ref_39","first-page":"90","article-title":"Stress of Self-Electric Field on Cell Membrane","volume":"13","author":"Niu","year":"1994","journal-title":"Chin. J. Biomed. Eng."},{"key":"ref_40","first-page":"280","article-title":"Dielectric Parameter Solution Algorithm Applied to Electrorotation Analysis of Spheroid Cells","volume":"42","author":"Zhang","year":"2012","journal-title":"J. Southeast Univ. Nat. Sci. Ed."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"3307","DOI":"10.1016\/S0006-3495(99)77483-7","article-title":"Dielectric properties of human leukocyte subpopulations determined by electrorotation as a cell separation criterion","volume":"76","author":"Yang","year":"1999","journal-title":"Biophys. J."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"2251","DOI":"10.1088\/0031-9155\/41\/11\/002","article-title":"The dielectric properties of biological tissues. 2. Measurements in the frequency range 10 Hz to 20 GHz","volume":"41","author":"Gabriel","year":"1996","journal-title":"Phys. Med. Biol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1007\/BF02474537","article-title":"The specific resistance of biological material\u2014A compendium of data for the biomedical engineer and physiologist","volume":"5","author":"Geddes","year":"1967","journal-title":"Med. Biol. Eng."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"170015","DOI":"10.1038\/sdata.2017.15","article-title":"Specific membrane capacitance, cytoplasm conductivity and instantaneous Young\u2019s modulus of single tumour cells","volume":"4","author":"Wang","year":"2017","journal-title":"Sci. Data"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"3022","DOI":"10.1038\/s41598-021-82622-5","article-title":"Photons detected in the active nerve by photographic technique","volume":"11","author":"Zangari","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"8606","DOI":"10.1364\/AO.503485","article-title":"Distributed loss-amplification modeling for the mid-infrared signal propagating in the myelinated and demyelinated nerve","volume":"62","author":"Zhang","year":"2023","journal-title":"Appl. Opt."},{"key":"ref_47","unstructured":"Li, J.S. (2024). Electromagnetic Fields and Microwave Engineering, Shanghai Scientific & Technical Publishers. (In Chinese)."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"19356","DOI":"10.1038\/s41598-022-23580-4","article-title":"Simulation of nerve fiber based on anti-resonant reflecting optical waveguide","volume":"12","author":"Omidi","year":"2022","journal-title":"Sci. Rep."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"659","DOI":"10.1007\/BF01008897","article-title":"A Model for the Complex Permittivity of Water at Frequencies Below 1 Thz","volume":"12","author":"Liebe","year":"1991","journal-title":"Int. J. Infrared Millim. Waves"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"10373","DOI":"10.1021\/jp960141g","article-title":"Far-infrared dielectric properties of polar liquids probed by femtosecond terahertz pulse spectroscopy","volume":"100","author":"Kindt","year":"1996","journal-title":"J. Phys. Chem."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"12301","DOI":"10.1073\/pnas.0604897103","article-title":"Solute-induced retardation of water dynamics probed directly by terahertz spectroscopy","volume":"103","author":"Heugen","year":"2006","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_52","unstructured":"Xie, C.F., and Rao, K.J. (1979). Electromagnetic Fields and Electromagnetic Waves, People\u2019s Education Press. (In Chinese)."}],"container-title":["Bioengineering"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2306-5354\/13\/8\/955\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T04:30:44Z","timestamp":1787632244000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2306-5354\/13\/8\/955"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,21]]},"references-count":52,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["bioengineering13080955"],"URL":"https:\/\/doi.org\/10.3390\/bioengineering13080955","relation":{},"ISSN":["2306-5354"],"issn-type":[{"value":"2306-5354","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,21]]}}}