{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:09:11Z","timestamp":1760148551732,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,9]],"date-time":"2023-05-09T00:00:00Z","timestamp":1683590400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS KAKENHI","award":["21K03960"],"award-info":[{"award-number":["21K03960"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In order to advance the development of sensors fabricated with monofunctional sensation systems capable of a versatile response to tactile, thermal, gustatory, olfactory, and auditory sensations, mechanoreceptors fabricated as a single platform with an electric circuit require investigation. In addition, it is essential to resolve the complicated structure of the sensor. In order to realize the single platform, our proposed hybrid fluid (HF) rubber mechanoreceptors of free nerve endings, Merkel cells, Krause end bulbs, Meissner corpuscles, Ruffini endings, and Pacinian corpuscles mimicking the bio-inspired five senses are useful enough to facilitate the fabrication process for the resolution of the complicated structure. This study used electrochemical impedance spectroscopy (EIS) to elucidate the intrinsic structure of the single platform and the physical mechanisms of the firing rate such as slow adaption (SA) and fast adaption (FA), which were induced from the structure and involved the capacitance, inductance, reactance, etc. of the HF rubber mechanoreceptors. In addition, the relations among the firing rates of the various sensations were clarified. The adaption of the firing rate in the thermal sensation is the opposite of that in the tactile sensation. The firing rates in the gustation, olfaction, and auditory sensations at frequencies of less than 1 kHz have the same adaption as in the tactile sensation. The present findings are useful not only in the field of neurophysiology, to research the biochemical reactions of neurons and brain perceptions of stimuli, but also in the field of sensors, to advance salient developments in sensors mimicking bio-inspired sensations.<\/jats:p>","DOI":"10.3390\/s23104593","type":"journal-article","created":{"date-parts":[[2023,5,10]],"date-time":"2023-05-10T01:57:51Z","timestamp":1683683871000},"page":"4593","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Correlations among Firing Rates of Tactile, Thermal, Gustatory, Olfactory, and Auditory Sensations Mimicked by Artificial Hybrid Fluid (HF) Rubber Mechanoreceptors"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9174-503X","authenticated-orcid":false,"given":"Kunio","family":"Shimada","sequence":"first","affiliation":[{"name":"Faculty of Symbiotic Systems Sciences, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107137","DOI":"10.1016\/j.nanoen.2022.107137","article-title":"Skin-inspired textile-based tactile sensors enable multifunctional sensing of wearables and soft robots","volume":"96","author":"Pang","year":"2022","journal-title":"Nano Energy"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2202470","DOI":"10.1002\/advs.202202470","article-title":"Multimodal sensors with decoupled sensing mechanisms","volume":"9","author":"Yang","year":"2022","journal-title":"Adv. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.bioelechem.2019.02.009","article-title":"Integrated olfaction, gustation and toxicity detection by a versatile bioengineered cell-based biomimetic sensor","volume":"128","author":"Gao","year":"2019","journal-title":"Bioelectrochemistry"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1201","DOI":"10.1002\/elan.201600047","article-title":"Sensor devices inspired by the five senses: A review","volume":"28","author":"Svechtarova","year":"2016","journal-title":"Electroanalysis"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2103734","DOI":"10.1002\/smll.202103734","article-title":"Recent advances in multiresponsive flexible sensors towards e-skin: A delicate design for versatile sensing","volume":"18","author":"Li","year":"2021","journal-title":"Small"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1039\/D0NR06550A","article-title":"Bio-inspired smart electronic-skin based on inorganic perovskite nanoplates for application in photomemories and mechanoreceptors","volume":"13","author":"Xu","year":"2021","journal-title":"Nanoscale"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Shimada, K. (2022). Morphological configuration of sensory biomedical receptors based on structures integrated by electric circuits and utilizing magnetic-responsive hybrid fluid (HF). Sensors, 22.","DOI":"10.3390\/s22249952"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1679\/aohc.51.1","article-title":"The structure and function of cutaneous sensory receptors","volume":"51","author":"Munger","year":"1988","journal-title":"Arch. Histol. Cytol."},{"key":"ref_9","unstructured":"Hongye, C., and Zhou, Y. (2021). Materials, Devices and Integrations, Woodhead Publishing."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"100451","DOI":"10.1016\/j.jsamd.2022.100451","article-title":"Engineered gelatin-based conductive hydrogels for flexible wearable electronic devices: Fundamentals and recent advances","volume":"7","author":"Wang","year":"2022","journal-title":"J. Sci. Adv. Mat. Devices"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"107525","DOI":"10.1016\/j.nanoen.2022.107525","article-title":"Self-powered perception system based on triboelectric nanogenerator and artificial neuron for fast-speed multilevel feature recognition","volume":"100","author":"Ye","year":"2022","journal-title":"Nano Energy"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"120625","DOI":"10.1016\/j.carbpol.2023.120625","article-title":"Flexible, sensitive and rapid humidity-responsive sensor based on rubber\/aldehyde-modified sodium carboxymethyl starch for human respiratory detection","volume":"306","author":"Zheng","year":"2023","journal-title":"Carbohydr. Poly."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"141233","DOI":"10.1016\/j.cej.2022.141233","article-title":"A conformable, durable, adhesive welded fiber mate for on-skin strain sensing","volume":"457","author":"Xie","year":"2023","journal-title":"Chem. Eng. J."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"103980","DOI":"10.1016\/j.biosystems.2019.103980","article-title":"Review: Methods of firing rate estimation","volume":"183","author":"Tomar","year":"2019","journal-title":"BioSystems"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"322","DOI":"10.3389\/fnins.2018.00322","article-title":"A digital hardware realization for spiking model of cutaneous mechanoreceptor","volume":"12","author":"Nezhad","year":"2018","journal-title":"Fron. Neur."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/0079-6107(95)00011-9","article-title":"Mammalian cutaneous mechanoreceptors","volume":"64","author":"Hamann","year":"1995","journal-title":"Prog. Biophys. Mol. Biol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.sna.2012.02.051","article-title":"A review of tactile sensing technologies with applications in biomedical engineering","volume":"179","author":"Tiwana","year":"2012","journal-title":"Sens. Actuators A Phys."},{"key":"ref_18","first-page":"2100352","article-title":"Engineered mechanosensors inspired by biological mechanosensilla","volume":"6","author":"Wang","year":"2021","journal-title":"Adv. Mater."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.biosystems.2019.03.003","article-title":"Temperature effects on neuronal firing rates and tonic-to-bursting transitions","volume":"180","author":"Burek","year":"2019","journal-title":"Biosystems"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1835","DOI":"10.1523\/JNEUROSCI.3132-16.2017","article-title":"Behavioral status influences the dependence of odorant-induced changes in firing on prestimulus firing rate","volume":"37","author":"Li","year":"2017","journal-title":"J. Neurosci."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Partouche, E., Adenis, V., Gnansia, D., Stahl, P., and Edeline, J.M. (2022). Increased threshold and reduced firing rate of auditory cortex neurons after cochlear implant insertion. Brain Sci., 12.","DOI":"10.3390\/brainsci12020205"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"964","DOI":"10.1068\/ic964","article-title":"Interaction between olfaction and gustation by using synchrony perception task","volume":"2","author":"Kobayakawa","year":"2011","journal-title":"i-Perception"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Gotow, N., and Kobayakawa, T. (2017). Simultaneity judgment using olfactory-visual, visual-gustatory, and olfactory-gustatory combinations. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0174958"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Shimada, K. (2023). Estimation of fast and slow adaptions in the tactile sensation of mechanoreceptors mimicked by hybrid fluid (HF) rubber with equivalent electric circuits and properties. Sensors, 23.","DOI":"10.3390\/s23031327"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jcis.2022.11.024","article-title":"Laser-structured microarray electrodes for durable stretchable lithium-ion battery","volume":"631","author":"Lu","year":"2023","journal-title":"J. Colloid Interface Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1500305","DOI":"10.1002\/advs.201500305","article-title":"An organic mixed ion-electron conductor for power electronics","volume":"3","author":"Malti","year":"2016","journal-title":"Adv. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2630","DOI":"10.1038\/s41467-018-05165-w","article-title":"Highly stretchable and transparent ionic conducting elastomers","volume":"9","author":"Shin","year":"2018","journal-title":"Nat. Commun."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"16108","DOI":"10.1063\/5.0124959","article-title":"Highly stretchable and sensitive silicone composites with positive piezoconductivity using nickel powder and ionic liquid","volume":"7","author":"Matsuda","year":"2023","journal-title":"APL Bioeng."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1706299","DOI":"10.1002\/adma.201706299","article-title":"A self-powered sensor mimicking slow- and fast-adapting cutaneous mechanoreceptors","volume":"30","author":"Chun","year":"2018","journal-title":"Adv. Mater."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/j.jnoncrysol.2013.06.018","article-title":"Dielectric relaxation studies on nanocomposites of rubber with nanofibrillated cellulose","volume":"378","author":"Ladhar","year":"2013","journal-title":"J. Non-Crys. Solids"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"272","DOI":"10.1016\/j.molliq.2015.04.020","article-title":"AC and DC electrical conductivity in natural rubber\/nanofibrillated cellulose nanocomposites","volume":"209","author":"Ladhar","year":"2015","journal-title":"J. Mol. Liquids"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"100640","DOI":"10.1016\/j.mser.2021.100640","article-title":"Approaches to deformable physical sensors: Electronic versus iontronic","volume":"146","author":"Kim","year":"2021","journal-title":"Mater. Sci. Eng. R. Rep."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1001","DOI":"10.1039\/D2CS00920J","article-title":"A guide for the characterization of organic electrochemical transistors and channel materials","volume":"52","author":"Ohayon","year":"2023","journal-title":"Chem. Soc. Rev."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Shimada, K. (2022). Artificial tongue embedded with conceptual receptor for rubber gustatory sensor by electrolytic polymerization technique with utilizing hybrid fluid (HF). Sensors, 22.","DOI":"10.3390\/s22186979"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/10\/4593\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:32:10Z","timestamp":1760124730000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/10\/4593"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,5,9]]},"references-count":34,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2023,5]]}},"alternative-id":["s23104593"],"URL":"https:\/\/doi.org\/10.3390\/s23104593","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2023,5,9]]}}}