{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T05:46:53Z","timestamp":1768283213717,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,8]],"date-time":"2021-03-08T00:00:00Z","timestamp":1615161600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"UNITECH CO.,LTD","award":["UNITECH_2020"],"award-info":[{"award-number":["UNITECH_2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Physiological signals are immediate and sensitive to neural and cardiovascular change resulting from brain stimulation, and are considered as a quantifying tool with which to evaluate the association between brain stimulation and cognitive performance. Brain stimulation outside a highly equipped, clinical setting requires the use of a low-cost, ambulatory miniature system. The purpose of this double-blind, randomized, sham-controlled study is to quantify the physiological biomarkers of the neural and cardiovascular systems induced by a microwave brain stimulation (MBS) device. We investigated the effect of an active MBS and a sham device on the cardiovascular and neurological responses of ten volunteers (mean age 26.33 years, 70% male). Electroencephalography (EEG) and electrocardiography (ECG) were recorded in the initial resting-state, intermediate state, and the final state at half-hour intervals using a portable sensing device. During the experiment, the participants were engaged in a cognitive workload. In the active MBS group, the power of high-alpha, high-beta, and low-beta bands in the EEG increased, and the power of low-alpha and theta waves decreased, relative to the sham group. RR Interval and QRS interval showed a significant association with MBS stimulation. Heart rate variability features showed no significant difference between the two groups. A wearable MBS modality may be feasible for use in biomedical research; the MBS can modulate the neurological and cardiovascular responses to cognitive workload.<\/jats:p>","DOI":"10.3390\/s21051896","type":"journal-article","created":{"date-parts":[[2021,3,8]],"date-time":"2021-03-08T12:12:18Z","timestamp":1615205538000},"page":"1896","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Quantifying Physiological Biomarkers of a Microwave Brain Stimulation Device"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5183-7631","authenticated-orcid":false,"given":"Iqram","family":"Hussain","sequence":"first","affiliation":[{"name":"Center for Medical Convergence Metrology, Korea Research Institute of Standards and Science, Daejeon 34113, Korea"},{"name":"Department of Medical Physics, University of Science &amp; Technology, Daejeon 34113, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seo","family":"Young","sequence":"additional","affiliation":[{"name":"Center for Medical Convergence Metrology, Korea Research Institute of Standards and Science, Daejeon 34113, Korea"},{"name":"Department of Medical Physics, University of Science &amp; Technology, Daejeon 34113, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chang Ho","family":"Kim","sequence":"additional","affiliation":[{"name":"UNITECH CO., Ltd., Seoul 08289, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5473-9597","authenticated-orcid":false,"given":"Ho Chee Meng","family":"Benjamin","sequence":"additional","affiliation":[{"name":"AI Research Group, Sewon Intelligence, Ltd., Seoul 04512, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1618-5906","authenticated-orcid":false,"given":"Se Jin","family":"Park","sequence":"additional","affiliation":[{"name":"Center for Medical Convergence Metrology, Korea Research Institute of Standards and Science, Daejeon 34113, Korea"},{"name":"Department of Medical Physics, University of Science &amp; Technology, Daejeon 34113, Korea"},{"name":"AI Research Group, Sewon Intelligence, Ltd., Seoul 04512, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1038\/s41582-018-0128-2","article-title":"Deep brain stimulation: Current challenges and future directions","volume":"15","author":"Lozano","year":"2019","journal-title":"Nat. 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