{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T14:05:21Z","timestamp":1785333921569,"version":"3.55.0"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T00:00:00Z","timestamp":1785283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurosci."],"abstract":"<jats:p>Fully in-ear Electroencephalography (EEG) configurations prioritize wearability and rapid setup but may constrain spatial sampling and signal-to-noise characteristics. We conducted a domain-specific evaluation of a generic-fit, fully intra-auricular dry-electrode EEG system benchmarked against simultaneous 32-channel BioSemi scalp EEG in 19 healthy adults. Rather than testing equivalence, we mapped strengths and boundary conditions across (i) resting-state alpha modulation (eyes open vs. eyes closed), (ii) auditory event-related-potentials (ERP; N1-P2 complex), and (iii) alpha ERSP during speech-in-noise. The in-ear configuration robustly captured canonical resting-state alpha increases during eyes-closed periods, despite reduced absolute amplitude relative to scalp EEG. In contrast, reliable N1-P2 responses were observed only in conventionally average-referenced scalp EEG; in-ear and adapted referencing configurations showed reduced component detectability with lower component SNR. During speech-in-noise, significant alpha ERSP deviations from baseline emerged in scalp EEG under less adverse listening conditions, whereas comparable deviations were not consistently detected in the minimal in-ear configuration. These findings indicate that signal detectability depends strongly on signal class, effect size, and recording geometry, providing configuration-aware guidance for study design and future in-ear EEG development.<\/jats:p>","DOI":"10.3389\/fnins.2026.1859327","type":"journal-article","created":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T13:20:30Z","timestamp":1785331230000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Signal-specific performance of in-ear EEG: strengths and limitations"],"prefix":"10.3389","volume":"20","author":[{"given":"Vanessa","family":"Frei","sequence":"first","affiliation":[{"name":"Department of Psychology, University of Florida","place":["Gainesville, FL, United States"]},{"name":"McKnight Brain Institute, University of Florida","place":["Gainesville, FL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pablo","family":"Mainar","sequence":"additional","affiliation":[{"name":"Logitech S.A.","place":["Lausanne, Switzerland"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Fritz","sequence":"additional","affiliation":[{"name":"Department of Informatics, University of Zurich","place":["Zurich, Switzerland"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean-Michel","family":"Chardon","sequence":"additional","affiliation":[{"name":"Logitech S.A.","place":["Lausanne, Switzerland"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nathalie","family":"Giroud","sequence":"additional","affiliation":[{"name":"Neurosciences of Communication, Language, and Cognition, University Hospital of Psychiatry Zurich","place":["Zurich, Switzerland"]},{"name":"International Max Planck Research School on the Life Course: Evolutionary and Ontogenetic Dynamics (LIFE), Dynamics","place":["Berlin, Germany"]},{"name":"Language and Medicine Center Zurich, Competence Center of Medical Faculty and Faculty of Arts and Sciences, University of Zurich","place":["Zurich, Switzerland"]},{"name":"Neuroscience Center Zurich, University of Zurich and ETH Zurich","place":["Zurich, Switzerland"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,29]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1264","DOI":"10.1109\/TBME.2022.3214428","article-title":"Alpha oscillations during effortful continuous speech: From scalp EEG to ear-EEG","volume":"70","author":"Ala","year":"2022","journal-title":"IEEE Trans. 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