{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T18:00:07Z","timestamp":1770832807223,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2019,11,12]],"date-time":"2019-11-12T00:00:00Z","timestamp":1573516800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["64532"],"award-info":[{"award-number":["64532"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006280","name":"Ministerio de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","award":["DPI2015-70415-C2-R"],"award-info":[{"award-number":["DPI2015-70415-C2-R"]}],"id":[{"id":"10.13039\/501100006280","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>When combined with assistive robotic devices, such as wearable robotics, brain\/neural-computer interfaces (BNCI) have the potential to restore the capabilities of handicapped people to carry out activities of daily living. To improve applicability of such systems, workload and stress should be reduced to a minimal level. Here, we investigated the user\u2019s physiological reactions during the exhaustive use of the interfaces of a hybrid control interface. Eleven BNCI-naive healthy volunteers participated in the experiments. All participants sat in a comfortable chair in front of a desk and wore a whole-arm exoskeleton as well as wearable devices for monitoring physiological, electroencephalographic (EEG) and electrooculographic (EoG) signals. The experimental protocol consisted of three phases: (i) Set-up, calibration and BNCI training; (ii) Familiarization phase; and (iii) Experimental phase during which each subject had to perform EEG and EoG tasks. After completing each task, the NASA-TLX questionnaire and self-assessment manikin (SAM) were completed by the user. We found significant differences (p-value &lt; 0.05) in heart rate variability (HRV) and skin conductance level (SCL) between participants during the use of the two different biosignal modalities (EEG, EoG) of the BNCI. This indicates that EEG control is associated with a higher level of stress (associated with a decrease in HRV) and mental work load (associated with a higher level of SCL) when compared to EoG control. In addition, HRV and SCL modulations correlated with the subject\u2019s workload perception and emotional responses assessed through NASA-TLX questionnaires and SAM.<\/jats:p>","DOI":"10.3390\/s19224931","type":"journal-article","created":{"date-parts":[[2019,11,13]],"date-time":"2019-11-13T09:11:27Z","timestamp":1573636287000},"page":"4931","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Physiological Responses During Hybrid BNCI Control of an Upper-Limb Exoskeleton"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0149-6469","authenticated-orcid":false,"given":"Francisco J.","family":"Badesa","sequence":"first","affiliation":[{"name":"Miguel Hern\u00e1ndez University of Elche, Av. Universidad w\/n, Ed. Innova, 03202 Alicante, Spain"},{"name":"Universidad de C\u00e1diz, Av. de la Universidad n10, 11519 Puerto Real, Spain"},{"name":"New technologies for Neurorehabilitation Lab., Av. de la Hospitalidad, s\/n, 28054 Madrid, Spain"}]},{"given":"Jorge A.","family":"Diez","sequence":"additional","affiliation":[{"name":"Miguel Hern\u00e1ndez University of Elche, Av. Universidad w\/n, Ed. Innova, 03202 Alicante, Spain"},{"name":"New technologies for Neurorehabilitation Lab., Av. de la Hospitalidad, s\/n, 28054 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3608-1039","authenticated-orcid":false,"given":"Jose Maria","family":"Catalan","sequence":"additional","affiliation":[{"name":"Miguel Hern\u00e1ndez University of Elche, Av. Universidad w\/n, Ed. Innova, 03202 Alicante, Spain"},{"name":"New technologies for Neurorehabilitation Lab., Av. de la Hospitalidad, s\/n, 28054 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3725-5694","authenticated-orcid":false,"given":"Emilio","family":"Trigili","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, Viale Rinaldo Piaggio 34, 56025 Pontedera, Pisa, Italy"}]},{"given":"Francesca","family":"Cordella","sequence":"additional","affiliation":[{"name":"Unit of Advanced Robotics and Human-centred Technologies, Campus Bio-Medico University of Rome, 00128 Rome, Italy"}]},{"given":"Marius","family":"Nann","sequence":"additional","affiliation":[{"name":"Applied Neurotechnology Laboratory, Department of Psychiatry and Psychotherapy, University Hopsital of T\u00fcbingen, Calwerstr. 14, 72076 T\u00fcbingen, Germany"}]},{"given":"Simona","family":"Crea","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, Viale Rinaldo Piaggio 34, 56025 Pontedera, Pisa, Italy"},{"name":"IRCCS Fondazione Don Carlo Gnocchi, Via Alfonso Capecelatro 66, 20148 Milan, Italy"},{"name":"Department of Excellence in Robotics &amp; AI, Scuola Superiore Sant\u2019Anna, 56025 Pontedera, Pisa, Italy"}]},{"given":"Surjo R.","family":"Soekadar","sequence":"additional","affiliation":[{"name":"Clinical Neurotechnology Laboratory, Department of Psychiatry and Psychotherapy (CCM), Charit\u00e9-Universit\u00e4tsmedizin Berlin, Charit\u00e9platz 1, 10117 Berlin, Germany"}]},{"given":"Loredana","family":"Zollo","sequence":"additional","affiliation":[{"name":"Unit of Advanced Robotics and Human-centred Technologies, Campus Bio-Medico University of Rome, 00128 Rome, Italy"}]},{"given":"Nicola","family":"Vitiello","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, Viale Rinaldo Piaggio 34, 56025 Pontedera, Pisa, Italy"},{"name":"IRCCS Fondazione Don Carlo Gnocchi, Via Alfonso Capecelatro 66, 20148 Milan, Italy"},{"name":"Department of Excellence in Robotics &amp; AI, Scuola Superiore Sant\u2019Anna, 56025 Pontedera, Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2510-3829","authenticated-orcid":false,"given":"Nicolas","family":"Garcia-Aracil","sequence":"additional","affiliation":[{"name":"Miguel Hern\u00e1ndez University of Elche, Av. Universidad w\/n, Ed. Innova, 03202 Alicante, Spain"},{"name":"New technologies for Neurorehabilitation Lab., Av. de la Hospitalidad, s\/n, 28054 Madrid, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,12]]},"reference":[{"key":"ref_1","unstructured":"European Commision (2010). People with disabilities have equal rights. The European Disability Strategy 2010\u20132020, European Commision."},{"key":"ref_2","first-page":"30","article-title":"Tools for brain\u2013computer interaction: A general concept for a hybrid BCI","volume":"5","author":"Breitwieser","year":"2011","journal-title":"Front. Neuroinform."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Choi, I., Rhiu, I., Lee, Y.S., Yun, M.W., and Nam, C.S. (2017). A Systematic Review of Hybrid Brain-Computer Interfaces: Taxonomy and Usability Perspectives. 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