{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T06:27:53Z","timestamp":1786343273749,"version":"build-2736575974"},"reference-count":49,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T00:00:00Z","timestamp":1786320000000},"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>The vagus nerve is a major neurophysiological pathway linking the brain and body, and schools provide a practical setting for delivering stress-regulation programs. This uncontrolled pilot study assessed the feasibility, safety, acceptability, and preliminary outcomes of a school-based intervention combining paced-breathing heart rate variability (HRV) biofeedback with transcutaneous auricular vagus nerve stimulation (taVNS). Seventeen vocational education and training students aged 15\u201317\u202fyears enrolled in six weekly individual sessions of up to 30\u202fmin using emWave\u00ae biofeedback and Parasym\u2122 taVNS. Feasibility was assessed through recruitment, six-session completion, acceptability, and adverse events. Exploratory outcomes included STAI-State anxiety, hair cortisol concentration (HCC), breathing self-regulation, and acute HRV indices. Recruitment was 50.0% (17\/34), and 14 participants completed all sessions (82.4%). Among the 14 participants who completed all six sessions, 13 completed the written satisfaction item: 12 rated the program 5\/5 and one rated it 4\/5 (M\u202f=\u202f4.92, SD\u202f=\u202f0.28). One mild, transient stimulation-related adverse event occurred and resolved after pausing and resuming at a lower intensity. STAI-State scores decreased from pre- to post-intervention, whereas HCC increased. In nine participants with paired HRV data from Sessions 1 and\/or 2, SDNN, RMSSD, lnHF, and lnLF were lower during combined paced breathing + taVNS than during spontaneous-breathing rest. Because the study was small, nonrandomized, uncontrolled, and the active components were always delivered together, these changes cannot be attributed to the intervention or to either component independently. The findings support cautious conclusions about deliverability and tolerability and provide information for a controlled trial, rather than evidence of efficacy.<\/jats:p>","DOI":"10.3389\/fnins.2026.1924550","type":"journal-article","created":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T05:30:33Z","timestamp":1786339833000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Feasibility, safety, and preliminary outcomes of a school-based intervention combining paced-breathing HRV biofeedback and transcutaneous auricular vagus nerve stimulation in adolescents"],"prefix":"10.3389","volume":"20","author":[{"given":"Ainara","family":"Aranberri-Ruiz","sequence":"first","affiliation":[{"name":"Department of Basic Psychological Processes and Their Development, University of the Basque Country (UPV\/EHU)","place":["Donostia-San Sebasti\u00e1n, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Unai Liberal","family":"Gra\u00f1a","sequence":"additional","affiliation":[{"name":"Department of Basic Psychological Processes and Their Development, University of the Basque Country (UPV\/EHU)","place":["Donostia-San Sebasti\u00e1n, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,10]]},"reference":[{"key":"ref1","first-page":"105","article-title":"De los Programas de Cualificaci\u00f3n Profesional Inicial (PCPI) a la Formaci\u00f3n Profesional B\u00e1sica: un estudio sobre el \u00e9xito y fracaso de alumnos en riesgo de exclusi\u00f3n educativa","volume":"13","author":"Amores","year":"2015","journal-title":"Rev. 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