{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T21:37:54Z","timestamp":1763415474158,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,5,29]],"date-time":"2019-05-29T00:00:00Z","timestamp":1559088000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Physiological arousal has been increasingly applied to monitor exploration (or navigation) of a virtual environment (VE), especially when the VE is designed to evoke an anxiety-related response. The present work aims to evaluate human physiological reactions to safe and unsafe VEs. We compared the effect of the presence of handrails in the VE in two different samples, young and older adults, through self-reports and physiological data: Electrodermal activation (EDA) and electrocardiogram (ECG) sensors. After navigation, self-report questionnaires were administered. We found that the VEs evoked a clearly differentiated perception of safety and unsafety demonstrated through self-reports, with older adults being more discriminative in their responses and reporting a higher sense of presence. In terms of physiological data, the effect of handrails did not provoke significant differences in arousal. Safety was better operationalized by discriminating neutral\/non-neutral spaces, where the reaction of older adults was more pronounced than young adults. Results serve as a basis for orienting future experiments in the line of VE and applied physiology usage in the architectural spaces design process. This specific work also provided a basis for the development of applications that integrate virtual reality and applied biofeedback, tapping into mobility and ageing.<\/jats:p>","DOI":"10.3390\/s19112447","type":"journal-article","created":{"date-parts":[[2019,5,29]],"date-time":"2019-05-29T11:31:28Z","timestamp":1559129488000},"page":"2447","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Physiological Arousal Quantifying Perception of Safe and Unsafe Virtual Environments by Older and Younger Adults"],"prefix":"10.3390","volume":"19","author":[{"given":"Sofia","family":"Leite","sequence":"first","affiliation":[{"name":"CINTESIS\u2014Center for Health Technology and Services Research, Faculty of Medicine, University of Porto, 4200-450 Porto, Portugal"}]},{"given":"Miguel S.","family":"Dias","sequence":"additional","affiliation":[{"name":"Instituto Universit\u00e1rio de Lisboa (ISCTE-IUL), ISTAR-IUL, 1649-026 Lisboa, Portugal"},{"name":"ADENE, Ag\u00eancia para a Energia, 1050-065 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2980-3686","authenticated-orcid":false,"given":"Sara","family":"Eloy","sequence":"additional","affiliation":[{"name":"Instituto Universit\u00e1rio de Lisboa (ISCTE-IUL), ISTAR-IUL, 1649-026 Lisboa, Portugal"}]},{"given":"Jo\u00e3o","family":"Freitas","sequence":"additional","affiliation":[{"name":"DefinedCrowd, 1500-399 Lisboa, Portugal"}]},{"given":"Sibila","family":"Marques","sequence":"additional","affiliation":[{"name":"Instituto Universit\u00e1rio de Lisboa (ISCTE-IUL), ISTAR-IUL, 1649-026 Lisboa, Portugal"}]},{"given":"Tiago","family":"Pedro","sequence":"additional","affiliation":[{"name":"Instituto Universit\u00e1rio de Lisboa (ISCTE-IUL), ISTAR-IUL, 1649-026 Lisboa, Portugal"}]},{"given":"L\u00e1zaro","family":"Ourique","sequence":"additional","affiliation":[{"name":"Instituto Universit\u00e1rio de Lisboa (ISCTE-IUL), ISTAR-IUL, 1649-026 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1007\/s10484-005-6381-3","article-title":"Review of four studies on the use of physiological reaction as a measure of presence in stressful Virtual Environments","volume":"30","author":"Meehan","year":"2005","journal-title":"Appl. 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