Abstract Background Recent studies have shown that playing prosocial video games leads to greater subsequent prosocial behavior in the real world. However, immersive virtual reality allows people to occupy avatars that are different from them in a perceptually realistic manner. We examine how occupying an avatar with the superhero ability to fly increases helping behavior. Principal Findings Using a two-by-two design, participants were either given the power of flight (their arm movements were tracked to control their flight akin to Superman’s flying ability) or rode as a passenger in a helicopter, and were assigned one of two tasks, either to help find a missing diabetic child in need of insulin or to tour a virtual city. Participants in the “super-flight” conditions helped the experimenter pick up spilled pens after their virtual experience significantly more than those who were virtual passengers in a helicopter. Conclusion The results indicate that having the “superpower” of flight leads to greater helping behavior in the real world, regardless of how participants used that power. A possible mechanism for this result is that having the power of flight primed concepts and prototypes associated with superheroes (e.g., Superman). This research illustrates the potential of using experiences in virtual reality technology to increase prosocial behavior in the physical world.

Citation: Rosenberg RS, Baughman SL, Bailenson JN (2013) Virtual Superheroes: Using Superpowers in Virtual Reality to Encourage Prosocial Behavior. PLoS ONE 8(1): e55003. https://doi.org/10.1371/journal.pone.0055003 Editor: Attila Szolnoki, Hungarian Academy of Sciences, Hungary Received: October 18, 2012; Accepted: December 21, 2012; Published: January 30, 2013 Copyright: © 2013 Rosenberg et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The authors have no support or funding to report. Competing interests: The authors have declared that no competing interests exist.

Introduction Experiences in virtual reality (VR) can be powerful–the user can feel as if he or she were actually “present” in the VR world. For instance, people walking on a log across a virtual chasm may know intellectually that they are in a VR world, but nonetheless experience many of the psychological symptoms they would experience if asked to cross an actual chasm (e.g., stress as measured by skin conductance [1]). Similarly, people with a fear of flying who therapeutically experience a virtual plane flight are helped to overcome their fears as much as people who therapeutically experience a real flight as part of a fear-of-flying course or therapy (see Rizzo & Kim [2] for a thorough discussion of therapy with virtual reality). The effects of virtual experiences can endure; for example: the plane-phobic person is able to take plane flights months later. [3] In this paper, we discuss how giving participants an enhanced ability in VR–the power to fly using their arms–affected helping behavior after they were out of the VR world. Recent work has examined how people come to “inhabit” or embody their avatars, which are virtual representations of themselves [4]. For example, Slater and colleagues [5] demonstrated that male participants experienced a so-called “body transfer illusion” even when their avatars were female. Moreover, a subsequent study by Kilteni, Normand, Sanchez-Vives, and Slater [6] demonstrated that participants could successfully transfer themselves into avatars that are shaped fundamentally differently from them, for example ones with arms much longer than human physical arms. These findings are particularly relevant to the current study in which participants occupy avatars that can perform similarly nonhuman feats–flying like Superman. We examined whether inhabiting an avatar that is helpful would cause someone to become more altruistic. Studies show that computer games that induce the user to behave in prosocial ways can lead users to engage in helping behaviors in the real world after the game is over. For example, Gentile and colleagues [7] helped to pioneer research on this topic with a series of studies with Singaporean children, Japanese children and adolescents, and U.S. undergraduate students. In the first study, Singaporean children reported which games they played most often and how often players hurt or helped others in the game. The children then completed a series of scales assessing their aptitude for prosocial behavior. In this study, the researchers found that prosocial game exposure was positively related to prosocial behavior and traits. In their second study, Japanese children’s video game habits and prosocial behaviors were tested over 3 to 4 months to assess the notion that habitually playing prosocial video games would increase prosocial behavior. Again, participants were surveyed on how often they played games with prosocial content (i.e., scenes in which characters help troubled persons). Results for the second study demonstrated a correlation between prosocial behavior and prosocial gaming. Finally, in their third study, college students participated in an experiment designed to assess causality of that relationship. Participants were randomly assigned to play either a prosocial video game or a neutral video game for 20 minutes. Next, participants were told to assign a partner 11 tangram puzzles out of 30 (10 easy, 10 medium, and 10 hard.) They were told that if their partner could complete 10 puzzles out of 11 then the partner would win a $10 gift certificate. Thus, partners could help each other by assigning easy puzzles or hurt each other by assigning hard ones. The researchers found a significant effect of game type on behavior. Those who played prosocial games were more likely to help their partner than those who played neutral games. In another study [8], participants were randomly assigned to play one of four video games: Lemmings, City Crisis, Tetris, and Lamers. Lemmings and City Crisis were deemed prosocial, the first being a game in which the participant must guide groups of small beings and save them by leading them to an exit, and the second being a game where the player acts as a helicopter pilot who has to rescue citizens from burning houses, support the police, and perform other helpful behaviors. Tetris was deemed a neutral game, and Lamers was classified by the experimenters as an aggressive form of Lemmings in which all beings must be killed before reaching the exit. After game play, participants who played a prosocial game were more likely to help pick up pencils that were “accidentally” spilled than participants who played the neutral or aggressive game. In a subsequent study [9], the researchers explored how prosocial video games increased the accessibility of prosocial thoughts. By using prosocial word recognition and recording response time they found that playing prosocial video games primed prosocial thoughts into semantic memory more so than when playing neutral video games. Prosocial computer or console games can enhance empathy [10], and immersive virtual reality appears to be at least equally suited to understanding and promoting empathy [11]. Virtual reality allows users to psychologically “become” the avatars, due to the realistic tracking of movements and perceptual similarity of avatar to self [12]. For example, Hershfield and colleagues [13] described studies in which virtual doppelgangers (virtual humans bearing a strong resemblance to the self) were created and manipulated to test how seeing an older version of oneself would affect the amount of money saved for retirement. In a series of studies testing this relationship, the researchers found that when participants interacted via their aged self, they were more likely to accept later monetary rewards over immediate ones. By implementing a series of controls, the researchers concluded that showing participants an older version of themselves opened up cognitive channels that allowed participants to be more concerned for their future and thus save more for retirement. Similarly, Fox and Bailenson [14] found that viewing a virtual representation of one’s self exercising or not exercising, and subsequently watching the virtual representation lose and gain weight because of it, increased the likelihood that one will exercise more in real life. Specifically, when exposing participants to a representation of their own avatar running versus their own avatar loitering, researchers found that participants in the running condition exhibited higher levels of exercise in the 24-hour period following the study than those who viewed their avatar loitering. This fosters the idea that virtual reality can influence behaviors for some time after treatment. In this vein, the current study sought to discover whether simply experiencing a virtual enhanced ability (i.e., the power of flight), and the unstated but implicit concepts that go along with such an enhanced ability (e.g., superpower) would lead participants subsequently to be more helpful. Specifically, we wanted to explore whether implicit but powerful priming of the concept “superhero” would lead to subsequent helping behavior. Other research has suggested this manipulation may be successful. For example, Nelson and Norton [15] found that participants who were primed with the category “superhero” were more likely to volunteer subsequently than participants in the control group. Participants were primed to think about either superheroes as a category, or about a prototype of that category–the superhero Superman. Participants were then asked how many hours they would be willing to volunteer at an organization. Participants primed with the general category of superheroes were significantly more likely to volunteer their time compared to participants in the other conditions. The current research takes these ideas one step further by allowing participants to embody a superhero ability rather than just think about the concept, and in measuring the helping effect afterward, we have the added strength of a behavioral measure rather than a self-reported measure. We specifically examined two variables in VR and their effect on subsequent helping behavior out of the VR world: (1) whether simply experiencing in VR an enhanced virtual ability (flying) would lead people to engage in prosocial behavior after the VR experience, and (2) whether performing a helping task in a virtual environment would lead people to help on an unrelated task after being in the virtual environment.

Discussion To sum up the results, flying participants were quicker to help than helicopter participants. In addition, there was a significant effect of number of pens picked up such that flyers picked up more pens than helicopter riders. In fact, six participants did not help at all, and these participants were all in the helicopter condition. The virtual power of flight facilitated subsequent helping behavior in the real world. However, there was somewhat of a ceiling effect in that the majority of participants, regardless of condition, helped. Whereas much research has been done on whether and how violent videogames can lead to aggressive behavior (see Anderson [21] and Anderson, Shibuya, and colleagues [22]), this is the first study to document that the “next” technology in video gaming–virtual reality–has the potential to facilitate prosocial behavior by allowing players to become superheroes. One hypothesized explanation for these results is that embodying the ability to fly in VR primes concepts and stereotypes related to superheroes in general or to Superman in particular, and thus facilitates subsequent helping behavior in the real world [23], [24]. Similarly, it is possible that embodying this power may do more than prime such concepts; it may shift participants’ self-concept or identity in a powerful way as “someone who helps,” at least briefly. Research supporting this hypothesis can be found in work on the role of self-concept in mediating the effect of concept activation on behavior [25], [26], [27]. (When the research results were shared with Paul Levitz, former DC Comics Publisher and President, and comic book editor and writer, Mr. Levitz noted that people familiar with superhero tropes implicitly know that after a character discovers a newfound superpower, the character’s task is to decide how to use it–for personal gain or for the greater good. Perhaps that implicit knowledge was operating in the current study, leading super flight participants to decide unconsciously and perhaps automatically to use their power for good.). Our study’s results are particularly intriguing in that the experimenter and the materials in the current study did not use the word “superhero” or the prefix “super-” before the virtual experience, and the word “superhero” or prefix “super-” were never uttered during or after the experiment had ended. However, because the participants in the flying conditions were given a superhuman ability, cognitive channels linking “super” activity (and related concepts and stereotypes) to heroism and helping behavior may have been opened, which would then influence their decision to help. Future studies can elucidate the underlying mechanism(s), such as teasing out the extent to which the priming of “superhero” (or Superman specifically) leads to subsequent helping behavior, and the extent to which such priming may activate a change in self-concept and, through this change, subsequent helping behavior. There was no main effect of task. One explanation for this lack of significance is that, despite the rich backstory for saving the child given to participants in both helping conditions, the actual saving task may not have been a vivid and immersive enough experience. Whereas participants were told they had a vial of insulin in their pocket, they did not see it or get to experience actually handing it to the child. Additionally, some participants noted that they felt that they didn’t truly “find” the child in the city. So spotting the child may have felt like happenstance rather than a saving moment. (Note that in this study, we did not perform a manipulation check to determine whether the instructions for the helping conditions were perceived by participants as we intended.). Another psychological basis for the difference between the super flight and helicopter conditions might be explained by an involvement versus observation discrepancy. Said another way, participants in the super flight conditions were active agents in the VR world, and participants in the helicopter conditions were comparatively passive as passengers. A similar discrepancy was found in a study by Calvert and Tan [28]: Young adults who played an aggressive virtual reality game showed increased physiological arousal and aggressive thoughts compared to those who observed someone else playing the game. While all participants in our study were actively immersed in virtual reality, there can be parallels drawn between Calvert and Tan’s observation condition and our helicopter condition. One participant in a helicopter condition was noted as saying “I felt like the helicopter pilot really did all the work. I don’t think I helped.” From the perspective of participants in the helicopter condition, it may have seemed that they were watching someone else actively explore/navigate the virtual city (and, with the use of yoking, they were) and thus, they were merely observers in the virtual world. A future study should allow participants in the helicopter condition to actively control their navigation, thus bringing them out of the observer role, to see if similar results ensue. The self-reported measure of orientation toward helping (the adapted POQ subscale) was not significant across groups. This lack of significance could be due to the hypothetical nature of many of the questions (e.g., “If a stranger left something behind, I would not tell him or her”) and the relatively infrequent opportunity to help in some of the specific ways described may have led participants to have difficulty accurately endorsing the frequency with which they would help in each of the specific ways. The lack of significance of this measure could also reflect the limitations of self-report measures in general. Bailenson, Aharoni, and colleagues [19] discuss the limitations of self-report and find, after a series of experiments, that results indicated by behavioral measures can be missed by self-report measures. The authors state that: “one of the greatest limitations in questionnaire-based studies is that participants are not always the most accurate judges of their own thoughts and feelings, so they often misreport affective and cognitive responses to stimuli. Therefore, dependent measures based on self-report questionnaires are best used in conjunction with other measures.” ([19] p. 7). Slater [20] reports a similar finding, pointing out that self-report measures in virtual reality often do not measure the construct they are designed to measure. The results may also have been influenced by other factors, such as the effect of presence in VR: Participants in the flying condition had significantly higher scores on the measure of presence, indicating that they felt more immersed in the experience and that it felt more “real.” Previous research suggests that stronger levels of presence in VR are more likely to affect behavior in the real world [29]. While the higher levels of presence in the flying condition compared to the helicopter condition offers some support for the idea that presence may be contributing to the difference in helping, a mediation analysis of presence on helping resulted in no significant effects for either the time taken to help (correlation: r = .15) or the number of pens picked up (r = -.13). Another factor that may have influenced the results is the homogeneity of our participant population: college students in their late teens to early twenties. Perhaps a different self-report measure and/or more behavioral measures of helping would elucidate the relationship between super flight and subsequent prosocial behavior. For instance, participants could be asked whether they’d like to volunteer to remain in the lab to help the researcher with a few more studies or if they would like to donate to a charity sponsored by the lab. Also, in this study we did not ensure that the experimenter was blind to condition. Future work should do so in order to prevent possible demand characteristics. This study is one of the first to examine the effects of prosocial behavior in VR and the prosocial effects of embodying a superpower. Future studies might address the questions: Will allowing people to experience super flight for longer periods of time lead them to be more prosocial afterward? Is the prosocial effect limited to the virtual experience of flight, or might it arise after other “superpowers” as well? What about embodying a specifically identified superhero such as Superman? Finally, if our results are replicated, future studies can examine the specific mechanisms at work.

Supporting Information File S1. This file contains the following supporting information. Text A Full Experiment Script. Text B Environmental Presence Scale. Text C Adapted Subscale of Prosocial Orientation Questionnaire. Text D Inferential Statistics for Non-Significant Effects. Table A Means and Standard Deviations for Measure of Motion Sickness (SSQ). Standard deviations are in parentheses. Higher numbers indicate more sickness. Table B Means and Standard Deviations for Measure of Intention to Help. Standard deviations are in parentheses. Lower numbers indicate more helpfulness. https://doi.org/10.1371/journal.pone.0055003.s001 (DOC)

Acknowledgments Thanks to Kyle Dumovic, Sonya Juang, Pamela Martinez and Mark Ulrich for their help in coding the virtual world, and thanks for Cody Karutz for coordinating the administrative aspects of running the study as well as editing a previous version of this paper. Moreover, thanks to Jakki Bailey, Laura Aymerich, and Andrea Stephenson Won for helpful comments on an earlier draft. Thanks also to Douglas Gentile who gave critical feedback in the planning phases of this study. Note that the subjects of Figures 1 and 4 have given written informed consent, as outlined in the PLOS consent form, to publication of their photograph.

Author Contributions Conceived and designed the experiments: Idea: RSR JNB. Design: JNB RSR SLB. Performed the experiments: SLB. Analyzed the data: SLB JNB. Wrote the paper: RSR SLB JNB.