{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T12:04:34Z","timestamp":1778155474549,"version":"3.51.4"},"reference-count":60,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,5,7]],"date-time":"2021-05-07T00:00:00Z","timestamp":1620345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Hodgkin and Huxley showed that even if the filaments are dissolved, a neuron\u2019s membrane alone can generate and transmit the nerve spike. Regulating the time gap between spikes is the brain\u2019s cognitive key. However, the time modula-tion mechanism is still a mystery. By inserting a coaxial probe deep inside a neuron, we have re-peatedly shown that the filaments transmit electromagnetic signals ~200 \u03bcs before an ionic nerve spike sets in. To understand its origin, here, we mapped the electromagnetic vortex produced by a filamentary bundle deep inside a neuron, regulating the nerve spike\u2019s electrical-ionic vortex. We used monochromatic polarized light to measure the transmitted signals beating from the internal components of a cultured neuron. A nerve spike is a 3D ring of the electric field encompassing the perimeter of a neural branch. Several such vortices flow sequentially to keep precise timing for the brain\u2019s cognition. The filaments hold millisecond order time gaps between membrane spikes with microsecond order signaling of electromagnetic vortices. Dielectric resonance images revealed that ordered filaments inside neural branches instruct the ordered grid-like network of actin\u2013beta-spectrin just below the membrane. That layer builds a pair of electric field vortices, which coherently activates all ion-channels in a circular area of the membrane lipid bilayer when a nerve spike propagates. When biomaterials vibrate resonantly with microwave and radio-wave, simultaneous quantum optics capture ultra-fast events in a non-demolition mode, revealing multiple correlated time-domain operations beyond the Hodgkin\u2013Huxley paradigm. Neuron holograms pave the way to understanding the filamentary circuits of a neural network in addition to membrane circuits.<\/jats:p>","DOI":"10.3390\/sym13050821","type":"journal-article","created":{"date-parts":[[2021,5,7]],"date-time":"2021-05-07T22:36:24Z","timestamp":1620426984000},"page":"821","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["Cytoskeletal Filaments Deep Inside a Neuron Are not Silent: They Regulate the Precise Timing of Nerve Spikes Using a Pair of Vortices"],"prefix":"10.3390","volume":"13","author":[{"given":"Pushpendra","family":"Singh","sequence":"first","affiliation":[{"name":"International Center for Materials and Nanoarchitectronics (MANA), Research Center for Advanced Measurement and Characterization (RCAMC), NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan"},{"name":"Amity School of Applied Science, Amity University Rajasthan, Kant Kalwar, NH-11C, Jaipur Delhi Higway, Jaipur, Rajasthan 303007, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5102-9482","authenticated-orcid":false,"given":"Pathik","family":"Sahoo","sequence":"additional","affiliation":[{"name":"International Center for Materials and Nanoarchitectronics (MANA), Research Center for Advanced Measurement and Characterization (RCAMC), NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Komal","family":"Saxena","sequence":"additional","affiliation":[{"name":"International Center for Materials and Nanoarchitectronics (MANA), Research Center for Advanced Measurement and Characterization (RCAMC), NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jhimli Sarkar","family":"Manna","sequence":"additional","affiliation":[{"name":"International Center for Materials and Nanoarchitectronics (MANA), Research Center for Advanced Measurement and Characterization (RCAMC), NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kanad","family":"Ray","sequence":"additional","affiliation":[{"name":"Amity School of Applied Science, Amity University Rajasthan, Kant Kalwar, NH-11C, Jaipur Delhi Higway, Jaipur, Rajasthan 303007, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Subrata","family":"Ghosh","sequence":"additional","affiliation":[{"name":"Chemical Science and Technology Division, CSIR-North East Institute of Science and Technology, NEIST, Jorhat, Assam 785006, India"},{"name":"Academy of Scientific and Innovative Research (AcSIR), CSIR-NEIST Campus, Jorhat, Assam 785006, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8823-4914","authenticated-orcid":false,"given":"Anirban","family":"Bandyopadhyay","sequence":"additional","affiliation":[{"name":"International Center for Materials and Nanoarchitectronics (MANA), Research Center for Advanced Measurement and Characterization (RCAMC), NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 3050047, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,7]]},"reference":[{"key":"ref_1","first-page":"620","article-title":"Recherches quantitatives sur l\u2019excitation \u00e9lectrique des nerfs trait\u00e9e comme une polarisation","volume":"9","author":"Lapicque","year":"1907","journal-title":"J. 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