{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T05:19:20Z","timestamp":1788153560853,"version":"build-2803163510"},"reference-count":26,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T00:00:00Z","timestamp":1787961600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100016168","name":"Ludwig Boltzmann Society","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100016168","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/01v1jam04","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>(1) Background: Evoked potentials (EPs) are an elegant, non-invasive, and reliable technique for assessing the functional integrity of neural pathways. They are, however, often limited by the difficulty and time needed to consistently distinguish signal from noise. (2) Methods: We have recently proposed a novel technique based on spectral domain evoked-to-background ratio (EBR) that enables fast data acquisition with online feedback about actual signal quality utilizing state of the art analog-to-digital conversion. Furthermore, we have developed a novel model-based signal-to-noise management concept allowing for suppression of biological and technical interference (swallowing, stimulation artifacts, electropolarization, and powerline potentials) and for online assessment of signal-to-noise ratio (SNR) for EPs. In this work, we experimentally confirmed this concept in ten healthy volunteers by investigating cortical EPs and high-frequency oscillations (HFOs) following median nerve stimulation. (3) Results: Both mathematical model and human data demonstrate that spectral target-band EBR governs the progress in SNR with increasing sweep count. For cortical EPs, SNR exceeded 10 dB beyond 90 averages in all participants. An SNR &gt; 20 dB documented excellent signal quality and reproducibility. For HFOs, the SNR shifted to lower values by 12 dB, displaying pronounced individual variation, however, with smaller variation of HFO-band background activity (1.9 vs. 7.6 dB between the 25% and 75% percentile). Thus, individual HFO responses are more important for actual signal extraction compared to background activity. In subjects displaying a high HFO amplitude, reproducibility was confirmed for less than 1000 sweeps. (4) Conclusions: The present investigations confirm that individual EBR is the major factor defining SNR. Background noise can be reduced to a negligible level. Online assessment of background activity will allow for the most accurate moment-to-moment visualization of raw signal quality. This will facilitate termination of the data acquisition and may be based on quantified signal quality rather than predefined sweep count.<\/jats:p>","DOI":"10.3390\/bioengineering13091008","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T02:08:58Z","timestamp":1788142138000},"page":"1008","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Online Signal-to-Noise Management for Evoked Potentials\u2014Assessing and Explaining Response Quality"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7292-2333","authenticated-orcid":false,"given":"Gerald","family":"Fischer","sequence":"first","affiliation":[{"name":"Institute of Electrical and Biomedical Engineering, UMIT TIROL\u2014Private University for Health Sciences and Health Technology, Eduard Wallnoefer Zentrum 1, 6060 Hall in Tirol, Austria"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-1773-2407","authenticated-orcid":false,"given":"Maria E.","family":"Holzknecht","sequence":"additional","affiliation":[{"name":"Department of Neurology, Hochzirl Hospital, 6170 Zirl, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3871-2890","authenticated-orcid":false,"given":"Jens","family":"Haueisen","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering and Informatics, Technische Universit\u00e4t Ilmenau, Gustav-Kirchhoff Str., 98693 Ilmenau, Germany"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6109-3368","authenticated-orcid":false,"given":"Daniel","family":"Baumgarten","sequence":"additional","affiliation":[{"name":"Department of Mechatronics, University of Innsbruck, Technikerstra\u00dfe, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2962-0903","authenticated-orcid":false,"given":"Markus","family":"Kofler","sequence":"additional","affiliation":[{"name":"Department of Neurology, Hochzirl Hospital, 6170 Zirl, Austria"},{"name":"Department of Neurology, Medical University Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106094","DOI":"10.1016\/j.bspc.2024.106094","article-title":"Spectral separation of evoked and spontaneous cortical activity, Part 1: Delta to high gamma band","volume":"92","author":"Fischer","year":"2024","journal-title":"Biomed. 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