{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T14:54:22Z","timestamp":1776092062915,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,20]],"date-time":"2023-02-20T00:00:00Z","timestamp":1676851200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We developed a wearable swallowing assessment device using a hetero-core fiber-optic pressure sensor for the detection of laryngeal movement during swallowing. The proposed pressure sensor (comfortably attached to the skin of the neck) demonstrated a high sensitivity of 0.592 dB\/kPa and a linearity of R2 = 0.995 within a 14 kPa pressure band, which is a suitable pressure for the detection of laryngeal movement. In addition, since the fabricated hetero-core fiber-optic pressure sensor maintains appreciable sensitivity over the surface of the sensor, the proposed wearable swallowing assessment device can accurately track the subtle pressure changes induced by laryngeal movements during the swallowing process. Sixteen male subjects and one female subject were evaluated in a variety of age groups ranging from 30 to 60 years old. For all subjects, characteristic swallowing waveforms (with two valleys based on laryngeal movements consisting of upward, forward, backward, and downward displacements) were acquired using the proposed wearable swallowing assessment device. Since the denoted time of the first valley in the acquired waveform determines the \u201caging effect\u201d, significant differences in swallowing functions among the different age groups were ultimately determined based on the time of the first valley. Additionally, by analyzing each age group using the proposed device, due to p-values being consistently less than 0.05, swallowing times were found to exhibit statistically significant differences within the same groups.<\/jats:p>","DOI":"10.3390\/s23042355","type":"journal-article","created":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T01:39:28Z","timestamp":1676943568000},"page":"2355","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["A Fiber-Optic Non-Invasive Swallowing Assessment Device Based on a Wearable Pressure Sensor"],"prefix":"10.3390","volume":"23","author":[{"given":"Masanori","family":"Maeda","sequence":"first","affiliation":[{"name":"Information Systems Science Major, Graduate of Science and Engineering, Soka University, 1-236 Tangi-Machi, Hachioji, Tokyo 192-8577, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8856-6807","authenticated-orcid":false,"given":"Miyuki","family":"Kadokura","sequence":"additional","affiliation":[{"name":"Information Systems Science Major, Graduate of Science and Engineering, Soka University, 1-236 Tangi-Machi, Hachioji, Tokyo 192-8577, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ryoko","family":"Aoki","sequence":"additional","affiliation":[{"name":"Faculty of Nursing, Soka University, 1-236 Tangi-Machi, Hachioji, Tokyo 192-8577, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noriko","family":"Komatsu","sequence":"additional","affiliation":[{"name":"Faculty of Nursing, Soka University, 1-236 Tangi-Machi, Hachioji, Tokyo 192-8577, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masaru","family":"Kawakami","sequence":"additional","affiliation":[{"name":"School of Nursing, Jichi Medical University, 3311-159 Yakushiji, Shimotsuke, Tochigi 329-0431, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuya","family":"Koyama","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kazuhiro","family":"Watanabe","sequence":"additional","affiliation":[{"name":"Department of Science and Engineering for Sustainable Innovation, Faculty of Science and Engineering, Soka University, 1-236 Tangi-Machi, Hachioji, Tokyo 192-8577, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michiko","family":"Nishiyama","sequence":"additional","affiliation":[{"name":"Department of Science and Engineering for Sustainable Innovation, Faculty of Science and Engineering, Soka University, 1-236 Tangi-Machi, Hachioji, Tokyo 192-8577, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,20]]},"reference":[{"key":"ref_1","unstructured":"United Nations (2022, November 30). 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