{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,18]],"date-time":"2026-04-18T05:02:01Z","timestamp":1776488521007,"version":"3.51.2"},"reference-count":61,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,5,18]],"date-time":"2023-05-18T00:00:00Z","timestamp":1684368000000},"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. Psychol."],"abstract":"<jats:p>Despite the widespread interest in leveraging non-player characters (NPCs) to enhance gameplay experiences, there is a gap in understanding of how NPC spectators (i.e., those virtual characters in the scene that watch users' actions) affect players. For instance, the impact of NPC spectators' presence and feedback on players' performance and experience has not been studied, especially in virtual reality (VR) exergames. This paper aims to fill this gap and reports two user studies that assess their effect on such games. Study 1 explored the impact of having NPC spectators present and their feedback available in a gesture-based VR exergame and found having NPC spectators and their feedback could improve players' game performance, experience, and exertion. Based on Study 1's results, we further explored two characteristics of the spectators\u2014their group size (small\/large) and their feedback (with\/without). The results show that (1) a large spectator number is more helpful since it improves the overall game experience (higher competence, flow, immersion), increases AvgHR% (the average heart rate percentage divided by the maximum heart rate), and enhances performance (improved players' combo performance and increased gesture success rate for particular gesture); (2) spectator feedback is instrumental in improving players' performance (higher gesture success rates, more combos performed successfully, more monster's combos prevented), enhancing game experience (positive affect, competence, flow, and immersion), and reducing negative game experience, increasing exertion (AvgHR% and burned more calories). Based on the results, we derived two main design recommendations for VR exergames that could pave the way for improving gameplay performance and game experience, especially among young adults.<\/jats:p>","DOI":"10.3389\/fpsyg.2023.1079132","type":"journal-article","created":{"date-parts":[[2023,5,18]],"date-time":"2023-05-18T08:18:03Z","timestamp":1684397883000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":10,"title":["Exploring the effect of the Group Size and Feedback of non-player character spectators in virtual reality exergames"],"prefix":"10.3389","volume":"14","author":[{"given":"Wenge","family":"Xu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kangyou","family":"Yu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuanru","family":"Meng","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diego","family":"Monteiro","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dominic","family":"Kao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hai-Ning","family":"Liang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2023,5,18]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"122","DOI":"10.1037\/0003-066X.37.2.122","article-title":"Self-efficacy mechanism in human agency","volume":"37","author":"Bandura","year":"1982","journal-title":"Am. Psychol"},{"key":"B2","doi-asserted-by":"publisher","first-page":"158","DOI":"10.1891\/0889-8391.13.2.158","article-title":"Self-efficacy: the exercise of control","volume":"13","author":"Bandura","year":"1997","journal-title":"J. Cogn. Psychother"},{"key":"B3","doi-asserted-by":"publisher","first-page":"265","DOI":"10.1207\/S1532785XMEP0303_03","article-title":"Social cognitive theory of mass communication","volume":"3","author":"Bandura","year":"2001","journal-title":"Media Psychol"},{"key":"B4","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1145\/3173574.3173982","article-title":"\u201cInteractive feedforward for improving performance and maintaining intrinsic motivation in VR exergaming,\u201d","author":"Barathi","year":"2018","journal-title":"Proceedings of the 2018 CHI Conference on Human Factors in Computing Systems"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1080\/0144929X.2023.2186145","article-title":"Exploring the influence of audience familiarity on speaker anxiety and performance in virtual reality and real-life presentation contexts","author":"Barrett","year":"2023","journal-title":"Behav. Inform. Technol"},{"key":"B6","doi-asserted-by":"publisher","first-page":"610","DOI":"10.1037\/0022-3514.46.3.610","article-title":"Choking under pressure: self-consciousness and paradoxical effects of incentives on skillful performance","volume":"46","author":"Baumeister","year":"1984","journal-title":"J. Pers. Soc. Psychol"},{"key":"B7","doi-asserted-by":"publisher","first-page":"41","DOI":"10.1016\/j.psychsport.2005.04.001","article-title":"Metamotivational and contextual effects on performance, self-efficacy, and shifts in affective states","volume":"7","author":"Bindarwish","year":"2006","journal-title":"Psychol. Sport Exerc"},{"key":"B8","doi-asserted-by":"publisher","first-page":"76","DOI":"10.1016\/j.jebo.2019.10.001","article-title":"Choking under pressure-evidence of the causal effect of audience size on performance","volume":"168","author":"B\u00f6heim","year":"2019","journal-title":"J. Econ. Behav. Organ"},{"key":"B9","doi-asserted-by":"publisher","first-page":"77","DOI":"10.1191\/1478088706qp063oa","article-title":"Using thematic analysis in psychology","volume":"3","author":"Braun","year":"2006","journal-title":"Qual. Res. Psychol"},{"key":"B10","doi-asserted-by":"publisher","first-page":"10473","DOI":"10.3390\/app112110473","article-title":"Effect of collaboration mode and position arrangement on immersive analytics tasks in virtual reality: a pilot study","volume":"11","author":"Chen","year":"2021","journal-title":"Appl. Sci"},{"key":"B11","author":"Costikyan","year":"2013","journal-title":"Uncertainty in Games"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1007\/s10209-023-00969-0","article-title":"Inclusive AR\/VR: accessibility barriers for immersive technologies","author":"Creed","year":"2023","journal-title":"Univers. Access Inform. Soc"},{"key":"B13","doi-asserted-by":"publisher","first-page":"627","DOI":"10.1037\/0033-2909.125.6.627","article-title":"A meta-analytic review of experiments examining the effects of extrinsic rewards on intrinsic motivation","volume":"125","author":"Deci","year":"1999","journal-title":"Psychol. Bull"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1093\/oso\/9780198794844.001.0001","author":"Drachen","year":"2018","journal-title":"Games User Research"},{"key":"B15","doi-asserted-by":"publisher","first-page":"10","DOI":"10.1145\/2967934.2968092","article-title":"\u201cThe influence of virtual agents on player experience and performance,\u201d","author":"Emmerich","year":"2016","journal-title":"Proceedings of the 2016 Annual Symposium on Computer-Human Interaction in Play, CHI PLAY '16"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1145\/3173574.3173674","author":"Emmerich","year":"2018","journal-title":"Watch Me Play: Does Social Facilitation Apply to Digital Games"},{"key":"B17","doi-asserted-by":"publisher","first-page":"83","DOI":"10.1080\/10413209908402952","article-title":"Effects of feedback on self-efficacy, performance, and choice in an athletic task","volume":"11","author":"Escarti","year":"1999","journal-title":"J. Appl. Sport Psychol"},{"key":"B18","doi-asserted-by":"publisher","first-page":"232","DOI":"10.1037\/0022-3514.91.2.232","article-title":"Subgoals as substitutes or complements: the role of goal accessibility","volume":"91","author":"Fishbach","year":"2006","journal-title":"J. Pers. Soc. Psychol"},{"key":"B19","doi-asserted-by":"publisher","first-page":"517","DOI":"10.1111\/j.1751-9004.2010.00285.x","article-title":"How positive and negative feedback motivate goal pursuit","volume":"48","author":"Fishbach","year":"2010","journal-title":"Soc. Pers. Psychol. Compass"},{"key":"B20","doi-asserted-by":"publisher","first-page":"424","DOI":"10.1080\/02701367.1991.10607544","article-title":"Does self-efficacy predict performance in experienced weightlifters?","volume":"62","author":"Fitzsimmons","year":"1991","journal-title":"Res. Q. Exerc. Sport"},{"key":"B21","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1145\/3313831.3376265","article-title":"\u201cVirtual reality games for people using wheelchairs,\u201d","author":"Gerling","year":"2020","journal-title":"Proceedings of the 2020 CHI Conference on Human Factors in Computing Systems, CHI'20"},{"key":"B22","doi-asserted-by":"publisher","first-page":"55","DOI":"10.1123\/tsp.17.1.55","article-title":"Self-efficacy, causal attribution, and track athletic performance following unexpected success or failure among elite sprinters","volume":"17","author":"Gernigon","year":"2003","journal-title":"Sport Psychol"},{"key":"B23","first-page":"1","article-title":"\u201cEffort vs. concentration: the asymmetric impact of pressure on NBA performance,\u201d","author":"Goldman","year":"2012","journal-title":"Proceedings of the MIT Sloan Sports Analytics Conference"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.1145\/3290688.3290752","article-title":"\u201cHIIT the road: using virtual spectator feedback in HIIT-based exergaming,\u201d","author":"Haller","year":"2019","journal-title":"Proceedings of the Australasian Computer Science Week Multiconference, ACSW 2019"},{"key":"B25","doi-asserted-by":"publisher","first-page":"e0217288","DOI":"10.1371\/journal.pone.0217288","article-title":"Validation of Polar OH1 optical heart rate sensor for moderate and high intensity physical activities","volume":"14","author":"Hettiarachchi","year":"2019","journal-title":"PLoS ONE"},{"key":"B26","author":"IJsselsteijn","year":"2013","journal-title":"The Game Experience Questionnaire"},{"key":"B27","doi-asserted-by":"publisher","first-page":"349","DOI":"10.1037\/0021-9010.64.4.349","article-title":"Consequences of individual feedback on behavior in organizations","volume":"64","author":"Ilgen","year":"1979","journal-title":"J. Appl. Psychol"},{"key":"B28","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1145\/3290605.3300388","article-title":"\u201cVirtual performance augmentation in an immersive jump & run exergame,\u201d","author":"Ioannou","year":"2019","journal-title":"Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems"},{"key":"B29","doi-asserted-by":"publisher","first-page":"38","DOI":"10.1016\/j.ijhcs.2018.05.003","article-title":"Validation of two game experience scales: the player experience of need satisfaction (PENS) and game experience questionnaire (GEQ)","volume":"118","author":"Johnson","year":"2018","journal-title":"Int. J. Hum. Comput. Stud"},{"key":"B30","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1080\/0144929X.2021.1906321","article-title":"The effects of observation in video games: how remote observation influences player experience, motivation, and behaviour","volume":"42","author":"Kao","year":"2021","journal-title":"Behav. Inform. Technol"},{"key":"B31","doi-asserted-by":"publisher","first-page":"151","DOI":"10.1145\/2658537.2658687","article-title":"\u201cEngaged by boos and cheers: the effect of co-located game audiences on social player experience,\u201d","author":"Kappen","year":"2014","journal-title":"Proceedings of the First ACM SIGCHI Annual Symposium on Computer-Human Interaction in Play, CHI PLAY '14"},{"key":"B32","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1027\/1864-1105\/a000175","article-title":"Effects of supportive feedback messages on exergame experiences: a mediating role of social presence","volume":"30","author":"Kim","year":"2016","journal-title":"J. Media Psychol"},{"key":"B33","doi-asserted-by":"publisher","first-page":"376","DOI":"10.1016\/j.chb.2014.03.067","article-title":"Body in the interactive game: how interface embodiment affects physical activity and health behavior change","volume":"36","author":"Kim","year":"2014","journal-title":"Comput. Hum. Behav"},{"key":"B34","doi-asserted-by":"publisher","first-page":"254","DOI":"10.1037\/0033-2909.119.2.254","article-title":"The effects of feedback interventions on performance: a historical review, a meta-analysis, and a preliminary feedback intervention theory","volume":"119","author":"Kluger","year":"1996","journal-title":"Psychol. Bull"},{"key":"B35","doi-asserted-by":"publisher","first-page":"351","DOI":"10.1145\/3311350.3347148","article-title":"\u201cThe role of uncertainty in moment-to-moment player motivation: a grounded theory,\u201d","author":"Kumari","year":"2019","journal-title":"Proceedings of the Annual Symposium on Computer-Human Interaction in Play, CHI PLAY '19"},{"key":"B36","doi-asserted-by":"publisher","first-page":"482","DOI":"10.3758\/BF03208286","article-title":"Cross-modality matches suggest anticipated stage fright a multiplicative power function of audience size and status","volume":"20","author":"Latan\u00e9","year":"1976","journal-title":"Percept. Psychophys"},{"key":"B37","doi-asserted-by":"publisher","first-page":"212","DOI":"10.1016\/0749-5978(91)90021-K","article-title":"Self-regulation through goal setting","volume":"50","author":"Latham","year":"1991","journal-title":"Theor. Cogn. Self-Regul"},{"key":"B38","doi-asserted-by":"publisher","first-page":"212","DOI":"10.2307\/258875","article-title":"A theory of goal setting & task performance","volume":"16","author":"Locke","year":"1991","journal-title":"Acad. Manage. Rev"},{"key":"B39","doi-asserted-by":"publisher","first-page":"667","DOI":"10.1007\/s12650-022-00889-w","article-title":"Effect of display23 platforms on spatial knowledge acquisition and engagement: an evaluation with 3d geometry visualizations","volume":"26","author":"Lu","year":"2023","journal-title":"J. Visual"},{"key":"B40","doi-asserted-by":"publisher","first-page":"143","DOI":"10.1109\/ISMAR.2018.00050","article-title":"\u201cEvaluating engagement level and analytical support of interactive visualizations in virtual reality environments,\u201d","author":"Lu","year":"2018","journal-title":"2018 IEEE International Symposium on Mixed and Augmented Reality"},{"key":"B41","doi-asserted-by":"publisher","first-page":"63","DOI":"10.1145\/800049.801756","article-title":"\u201cHeuristics for designing enjoyable user interfaces: lessons from computer games,\u201d","author":"Malone","year":"1982","journal-title":"Proceedings of the 1982 Conference on Human Factors in Computing Systems, CHI '82"},{"key":"B42","doi-asserted-by":"publisher","first-page":"203","DOI":"10.1093\/oso\/9780198794844.003.0013","article-title":"\u201cChapter 13: The rapid iterative test and evaluation method (rite),\u201d","author":"Medlock","year":"2018","journal-title":"Games User Research"},{"key":"B43","doi-asserted-by":"publisher","first-page":"62","DOI":"10.1007\/978-3-030-63426-1_7","article-title":"\u201cEvaluating the need and effect of an audience in a virtual reality presentation training tool,\u201d","author":"Monteiro","year":"","journal-title":"Computer Animation and Social Agents"},{"key":"B44","doi-asserted-by":"publisher","first-page":"713","DOI":"10.1109\/ISMAR50242.2020.00102","article-title":"\u201cAn in-depth exploration of the effect of 2d\/3d views and controller types on first person shooter games in virtual reality,\u201d","author":"Monteiro","year":"","journal-title":"2020 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)"},{"key":"B45","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1007\/s10209-023-00985-0","article-title":"\u201cEffects of audience familiarity on anxiety in a virtual reality public speaking training tool,\u201d","author":"Monteiro","year":"2023","journal-title":"Universal Access in the Information Society"},{"key":"B46","doi-asserted-by":"publisher","first-page":"303","DOI":"10.1109\/VR46266.2020.00050","article-title":"\u201cThe effects of virtual audience size on social anxiety during public speaking,\u201d","author":"Mostajeran","year":"2020","journal-title":"2020 IEEE Conference on Virtual Reality and 3D User Interfaces (VR)"},{"key":"B47","doi-asserted-by":"publisher","first-page":"697","DOI":"10.1111\/j.1600-0838.2012.01445.x","article-title":"Age-predicted maximal heart rate in healthy subjects: the hunt fitness study","volume":"23","author":"Nes","year":"2013","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"B48","first-page":"1","article-title":"Resting pulse rate reference data for children, adolescents, and adults: United States, 1999-2008","volume":"41","author":"Ostchega","year":"2011","journal-title":"Natl. Health Stat. Rep"},{"key":"B49","doi-asserted-by":"publisher","first-page":"27","DOI":"10.4018\/IJCALLT.2020010103","article-title":"University eap students' perceptions of using a prototype virtual reality learning environment to learn writing structure","volume":"10","author":"Pack","year":"2020","journal-title":"Int. J. Comput. Assist. Lang. Learn. Teach"},{"key":"B50","doi-asserted-by":"publisher","first-page":"175","DOI":"10.1080\/15213269.2012.673850","article-title":"Need satisfaction supportive game features as motivational determinants: an experimental study of a self-determination theory guided exergame","volume":"15","author":"Peng","year":"2012","journal-title":"Media Psychol"},{"key":"B51","doi-asserted-by":"publisher","first-page":"67","DOI":"10.1055\/a-0631-0920","article-title":"The polar oh1 optical heart rate sensor is valid during moderate-vigorous exercise","volume":"2","author":"Schubert","year":"2018","journal-title":"Sports Med. Int. Open"},{"key":"B52","first-page":"338","article-title":"Revision of the physical activity readiness questionnaire (PAR-Q)","volume":"17","author":"Thomas","year":"1993","journal-title":"Can. J. Sport Sci"},{"key":"B53","doi-asserted-by":"publisher","DOI":"10.1109\/TG.2022.3178539","article-title":"Real-time prediction of simulator sickness in virtual reality games","author":"Wang","year":"","journal-title":"IEEE Trans. Games"},{"key":"B54","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1145\/3522610","article-title":"Effect of render resolution on gameplay experience, performance, and simulator sickness in virtual reality games","volume":"5","author":"Wang","year":"","journal-title":"Proc. ACM Comput. Graph. Interact. Tech"},{"key":"B55","doi-asserted-by":"publisher","first-page":"143","DOI":"10.1145\/1978942.1978963","article-title":"\u201cThe aligned rank transform for nonparametric factorial analyses using only anova procedures,\u201d","author":"Wobbrock","year":"2011","journal-title":"Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, CHI '11"},{"key":"B56","doi-asserted-by":"publisher","first-page":"e29330","DOI":"10.2196\/29330","article-title":"Effects of an immersive virtual reality exergame on university students' anxiety, depression, and perceived stress: pilot feasibility and usability study","volume":"9","author":"Xu","year":"","journal-title":"JMIR Serious Games"},{"key":"B57","doi-asserted-by":"publisher","first-page":"15","DOI":"10.2196\/preprints.17972","article-title":"Results and guidelines from a repeated-measures design experiment comparing standing and seated full-body gesture-based immersive virtual reality exergames: within-subjects evaluation","volume":"8","author":"Xu","year":"","journal-title":"JMIR Serious Games"},{"key":"B58","doi-asserted-by":"publisher","first-page":"98","DOI":"10.1145\/3383668.3419958","article-title":"\u201cVirusboxing: a HIIT-based VR boxing game,\u201d","author":"Xu","year":"","journal-title":"Extended Abstracts of the 2020 Annual Symposium on Computer-Human Interaction in Play, CHI PLAY '20"},{"key":"B59","doi-asserted-by":"publisher","first-page":"14","DOI":"10.1145\/3411764.3445801","article-title":"\u201cEffect of gameplay uncertainty, display type, and age on virtual reality exergames,\u201d","author":"Xu","year":"","journal-title":"Proceedings of the 2021 CHI Conference on Human Factors in Computing Systems, CHI '21"},{"key":"B60","doi-asserted-by":"publisher","first-page":"1134","DOI":"10.1080\/10447318.2022.2098559","article-title":"Acceptance of virtual reality exergames among Chinese older adults","volume":"39","author":"Xu","year":"2022","journal-title":"Int. J. Hum. Comput. Interact"},{"key":"B61","doi-asserted-by":"publisher","first-page":"10","DOI":"10.1089\/g4h.2019.0102","article-title":"Studying the effect of display type and viewing perspective on user experience in virtual reality exergames","volume":"9","author":"Xu","year":"","journal-title":"Games Health J"}],"container-title":["Frontiers in Psychology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpsyg.2023.1079132\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,5,18]],"date-time":"2023-05-18T08:18:08Z","timestamp":1684397888000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpsyg.2023.1079132\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,5,18]]},"references-count":61,"alternative-id":["10.3389\/fpsyg.2023.1079132"],"URL":"https:\/\/doi.org\/10.3389\/fpsyg.2023.1079132","relation":{},"ISSN":["1664-1078"],"issn-type":[{"value":"1664-1078","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,5,18]]},"article-number":"1079132"}}