{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T15:48:26Z","timestamp":1788191306900,"version":"build-2803163510"},"reference-count":45,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T00:00:00Z","timestamp":1774483200000},"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\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t              https:\/\/ror.org\/01h0zpd94","doi-asserted-by":"publisher","award":["62106041"],"award-info":[{"award-number":["62106041"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t              https:\/\/ror.org\/01h0zpd94","doi-asserted-by":"publisher","award":["62204204"],"award-info":[{"award-number":["62204204"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"publisher","award":["223202100019"],"award-info":[{"award-number":["223202100019"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Innovation 2030-Major Project","award":["2022ZD0208601"],"award-info":[{"award-number":["2022ZD0208601"]}]},{"name":"Sichuan Science and Technology Program","award":["2025YFMS0021"],"award-info":[{"award-number":["2025YFMS0021"]}]},{"name":"Shanghai Sailing Program","award":["21YF1451000"],"award-info":[{"award-number":["21YF1451000"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>This study presents a modular and scalable wearable functional near-infrared spectroscopy (fNIRS) system for high-resolution cerebral hemodynamic signal acquisition. The system is based on compact optoelectronic modules and supports mixed measurements using short-separation and long-separation channels, offering good scalability and spatial adaptability. The integrated quartz light guide structure improves optical coupling efficiency between the probe and scalp. A series of in vivo experiments validated system performance. In a forearm arterial occlusion experiment, the system accurately captured concentration changes in oxygenated and deoxygenated hemoglobin during blood flow blockade and reperfusion, with large effect sizes (Cohen\u2019s d &gt; 0.9). In a prefrontal cortex Valsalva experiment, the biphasic response characteristic of neurovascular coupling was successfully resolved. In a 2-back working memory task, the system identified a task-related frequency component (0.0227 Hz) and right-lateralized prefrontal cortex activation (p = 0.023). These results demonstrate that the system exhibits a good signal-to-noise ratio and temporal dynamic response, enabling high-resolution mapping of regional hemodynamic changes. This work provides an effective solution for the development of wearable, modular, and high-precision multi-channel fNIRS systems.<\/jats:p>","DOI":"10.3390\/bios16040192","type":"journal-article","created":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T11:12:25Z","timestamp":1774609945000},"page":"192","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Miniaturized and Modular Wearable Functional Near-Infrared Spectroscopy (fNIRS) Sensing Module for High-Density Cerebral Hemodynamic Monitoring"],"prefix":"10.3390","volume":"16","author":[{"given":"Mengjie","family":"Fang","sequence":"first","affiliation":[{"name":"School of Information and Intelligent Science, Donghua University, Shanghai 201620, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinlong","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Information and Intelligent Science, Donghua University, Shanghai 201620, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2655-4840","authenticated-orcid":false,"given":"Bowen","family":"Ji","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Unmanned Aerial Vehicle Technology, Unmanned System Research Institute, School of Artificial Intelligence, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9340-9061","authenticated-orcid":false,"given":"Le","family":"Li","sequence":"additional","affiliation":[{"name":"School of Life Science and Technology, Northwestern Polytechnical University, Xi\u2019an 710129, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2317-6263","authenticated-orcid":false,"given":"Kunpeng","family":"Gao","sequence":"additional","affiliation":[{"name":"School of Information and Intelligent Science, Donghua University, Shanghai 201620, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1186\/s40708-023-00199-3","article-title":"Brain\u2013computer interface: Trend, challenges, and threats","volume":"10","author":"Maiseli","year":"2023","journal-title":"Brain Inform."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1645","DOI":"10.1109\/TCBB.2021.3052811","article-title":"EEG-Based Brain-Computer Interfaces (BCIs): A Survey of Recent Studies on Signal Sensing Technologies and Computational Intelligence Approaches and Their Applications","volume":"18","author":"Gu","year":"2021","journal-title":"IEEE\/ACM Trans. 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