copresence in virtual environments

Copresence in Virtual Environments

Celeste Campos-Castillo*University of Iowa

Abstract

Copresence, the sense of ‘‘being together’’ with others, is at the center of theories about socialinteraction. It is an intra-individual sense that stems from and shapes the social context. Recentresearch on copresence in virtual environments (VEs), synthetic simulations of existing experiences(e.g., desktop computer environments, ‘‘virtual reality’’), demonstrates the variability in whichpeople experience copresence with others who are not sharing in the same time or space. At thesame time, experimental researchers in sociology are using VEs as a methodological tool, yetremain unaware about the ramifications of varying levels of copresence for the social processesunder investigation. The goal of this review is to introduce sociologists to the research on copres-ence, specifically highlighting findings and gaps important for those who use VEs in their researchpractice. An understanding of how copresence occurs in VEs can improve how well sociologistsdesign experiments to advance theories about interpersonal behavior.

Copresence, or the sense of being with another (Schroeder 2006), forms the basis ofAllport’s (1954) definition of social psychology. Because of copresence (or lack thereof),people develop their thoughts and behavior during a specific situation as well as cumula-tively during their life course. Recent research explicitly dissecting the properties ofcopresence is fueled by a desire to understand interaction in virtual environments (VEs).At the same time, sociologists are increasingly using VEs as methodological tools, butremain unaware of relevant research on copresence in these environments. Perhaps thegap in knowledge exists because sociologists, in general, rarely study processes involvingVEs (Cerulo 2009; DiMaggio 2001) or because the research in this area is highly interdis-ciplinary and can at times cause overload when attempting to compose a coherent imageof findings (Cavanagh 2007). The gap is hindering the advancement of theories in socio-logical social psychology, as psychological social psychologists are already aware of this lit-erature (Blascovich et al. 2002).

I organize this review of the literature with the goal of presenting a sociologicalunderstanding of how copresence fluctuates in these settings that will help advance the-ories of social interaction. Put in methodological terms, the unfamiliarity of thisresearch on copresence means that it acts as an unintentional moderating variable inexperimental research within sociology. I describe a variety of ways in which copres-ence fluctuates in VEs. I connect this discussion to how copresence relates to both theinternal and external validity of laboratory experiments designed to test social theoriesabout face-to-face interactions. I end with a gap in the literature on copresence thatneeds to be addressed to advance our methodological progress in experimental socio-logy. Throughout my review, I focus on copresence with any general other in a virtualenvironment, although with whom we share copresence certainly matters (Zhao andElesh 2008).

Sociology Compass 6/5 (2012): 425–433, 10.1111/j.1751-9020.2012.00467.x

ª 2012 Blackwell Publishing Ltd

Definitions

The terms ‘‘copresence’’ and ‘‘VEs’’ may conjure up lay definitions, making it importantthat I first outline precise definitions to avoid confusion. By copresence, I refer to Goff-man’s (1959) notion of our sensory awareness of another. Our sensations are continuousvariables, and thus copresence is a continuous variable (Biocca et al. 2004). On the lowerend of this continuum are our automatic sensations that are difficult to consciously con-trol, such as the changes to our skin conductance that occur as the result of othersapproaching us (McBride et al. 1965). At the higher end of the continuum are our moreconscious sensations, as when we are motivated to experience the emotion others areexpressing (Klein and Hodges 2001). It is this variability and subjectivity that was over-looked by social scientists prior to the rise of mediated communication, and is the pre-mise for the issues I address in this review.

By virtual environment (VE), I refer to a synthetic simulation of an existing experience(Blascovich et al. 2002; McCall & Blascovich 2009). These include vignettes, which arerich descriptions of a scenario generally presented in text, to digital VEs created by com-puter programs (e.g., Facebook, Second Life, Sims). These digital VEs can be as simple asa chat room appearing on a desktop computer display with two-dimensional pictures rep-resenting interactants to a complex immersive situation where a participant uses a head-mounted display that renders and updates three-dimensional images emitted based ontheir position in a physical space1. The latter situation generally encompasses what peoplethink of when they hear the phrase ‘‘virtual reality’’ (McCall & Blascovich 2009), and Irefer to this specific type of VE as an immersive virtual environment (IVE). Two otherconcepts important for discussing copresence in VEs are ‘‘avatars’’ and ‘‘agents.’’ Both aredigital representations of others (either two- or three-dimensional), with agents beingrepresentations that are computer-controlled and avatars being representations that arecontrolled by ‘‘real-life’’ others.

Characteristics of VEs that shape copresence

Much research in VEs has assessed how known social processes transfer over to an inter-action in a VE (see the following for some recent reviews: McCall & Blascovich 2009;Sivunen and Hakonen 2011). Briefly, studies have replicated classic social psychologicalfindings from research in bystander intervention (Markey 2000), social facilitation andinhibition (Hoyt et al. 2006), obedience (Slater et al. 2006), and proxemics (Bailensonet al. 2003) in VE settings. We can state firmly now that social processes within a VEcan mirror those seen in laboratory and natural experiments, even when participantsknow that the other actors appearing in the VE are only agents. These processes transferover because it is the implied or imagined presence of another in a VE, to draw on All-port’s (1954) famous description of social psychology, which changes the behavior of anindividual from that which we would see if the individual was alone in the VE. Inother words, as researchers we can use VEs to replicate face-to-face situations.

The extent that these processes from face-to-face situations are replicated in VEs, how-ever, is generally contingent on the level of copresence with the others represented in aVE (Slater 2009). Different features of a VE can cause fluctuations in copresence, which Ireview next. The emphasis here will be on digital VEs because of the recent trendsamong sociologists in experimental designs. As will be seen in this review, what makescopresence sociological is its connection to the social context (Zhao and Elesh 2008).

426 Copresence in Virtual Environments

ª 2012 Blackwell Publishing Ltd Sociology Compass 6/5 (2012): 425–433, 10.1111/j.1751-9020.2012.00467.x

VE setting

Copresence can be shaped by our sense of environmental presence in the VE setting,which is sometimes referred to simply in the literature as ‘‘presence’’ (e.g., Garau et al.2008; Schroeder 2006; Slater 2009). Environmental presence is our sense that we areinvolved in the VE setting, and forget about our actual physical surroundings. VE settingscan afford more or less copresence (Zhao 2003). The form of the digital VE can shapecopresence, with immersive VEs generally offering greater copresence than desktop ver-sions and the availability of visual information leading to more copresence than when it isabsent or substituted by textual information (Schroeder 2006). Two other features of aVE setting are key: (1) the appearance of the VE; and (2) the interactability with otherobjects.

The appearance of the VE setting can alter a user’s copresence. Light colors andtextures on walls, for example, make users feel greater intimacy with others (Pressly &Heesacker 2001). Similarly, research participants who were in an IVE mentioned duringin-depth interviews how they actively avoided areas that did not appear to be well-lit(Garau et al. 2008). This also suggests that a user’s placement in IVEs is important foroutcomes. For example, research suggests that users who were placed closer to a speaker(from their perspective within the IVE) learn more from the speaker’s presentation thatthose who were placed farther away (Bailenson et al. 2008a,b; McCall et al. 2009).

A second key feature is the interactability with other objects, or the extent that itappears as if actions perceived in the environment are a result of our own. The appear-ance of interactability is positively related to our sense of presence in the VE setting(Slater 2009). Asynchronous modes of interaction (e.g., email and text messaging), forexample, generally offer lower senses of copresence than synchronous modes (e.g.,Nowak et al. 2009).

Representation of others

All else being equal, we achieve greater copresence with others in a face-to-face than ina mediated interaction (Zhao 2003). Research on copresence with others in VEs hasbegun to identify what precisely it is about face-to-face interaction that can heightencopresence, and in turn use this information to promote copresence in VEs.

Simply depicting a representation (either static or animated) of another can instill thesense that someone is present and willing to collaborate (Baylor and Ryu 2003; Heeter1995; Nam and Chung 2008). Thus, even the simplest desktop VEs can increase user co-presence with others by providing still images of others during the interaction. Still morepowerful would be a digital representation of oneself because of similarity-based attractionprinciples (Byrne 1971) that show that we tend to be attracted more to others when theyare similar to us. As such, when we are in an IVE with another agent and that agentresembles ourselves, we exhibit more intimacy behaviors with the agent (such as standingcloser to it) than when the agent is a digital representation of someone else (Bailensonet al. 2001, 2008a,b).

Designers of VEs dedicate much effort to increasing the visual fidelity (or photorealism)of the digital representation of others. However, the behavioral realism of a representationexerts the greatest effect on a user’s copresence, particularly when the representation isknown to be an agent as opposed to an avatar (Blascovich et al. 2002). Just like with theVE setting itself, others who are depicted in the VE must appear interactive to increase auser’s copresence with these others. Having the agent or avatar look up as a user walks

Copresence in Virtual Environments 427


up to it in an IVE, for example, can create changes to the user’s skin conductance (Garauet al. 2005) that mirror those seen when a person sharing the same physical space per-forms the same action (McBride et al. 1965). Similarly, when the eye gaze of the agentor avatar appears to follow the user around an IVE, users follow the informal rules aboutmaintaining interpersonal distance (Hall 1966) between themselves and this virtual other(Bailenson et al. 2003).

Testing social theories with VE experiments

With an understanding of how the design of the VE can affect copresence, we can turnto practical considerations. I outline some concrete examples of when to increase ordecrease copresence that pertain to sociologists interested in using VEs as a methodologi-cal tool in experimental research.

VEs are increasingly being used in laboratory experiments in favor of more traditionalmethods where experimenters, confederates (an accomplice of the researcher who seem-ingly is unaware of the purpose behind the study), and research participants communicatingface-to-face (Blascovich et al. 2002; Rashotte et al. 2005). Considerations of copresencecan facilitate the use of VEs in experimental research in a variety of ways, and avoid unin-tentional patterns in results. A research participant’s copresence with others in the VE isassociated with the experiment’s internal validity, and in turn, its external validity.

Internal validity

In experimental methods, internal validity is the extent that a study is able to demonstratethat observed differences are due to the levels of the independent variable and rule outalternative causes (Campbell and Stanley 1963). Part of establishing the internal validity ofan experiment is demonstrating that the stimulus was strong enough to elicit the hypoth-esized response. This concern goes beyond any given study, but also for future studieswhere researchers are attempting to reproduce results using the same stimulus materials.The Trier Social Stress Test (Kirschbaum et al. 1993), for example, is an experimentalsetting that underwent a number of modifications before it became a standardized proto-col to elicit a stress response that was strong enough to be reliably detected with biomar-kers (as opposed to self-reports). The common design in experiments within the statuscharacteristics theory tradition (Berger 2007) also underwent rigorous testing develop atask setting that elicited a reliable level of uncertainty to open the opportunity for influ-ence to occur. Having a standardized protocol that is known to elicit the desired responsecan minimize concerns over not finding expected results when attempting to reproduceand extend prior research, and is paramount to the cumulative growth of knowledge.

When the stimulus is a representation of another person (avatar or agent) in a VE, anissue arises about whether the representation can elicit the desired response from aresearch participant similarly to that observed in a face-to-face experiment. Recall thatthe level of copresence a user feels with others dictates the extent that social processesknown to appear in face-to-face situations will unfold. Increasing the participant’s copres-ence with the representation, then, will increase the strength of the responses (as seen inthe means of outcome measures) that are hypothesized to be (directly or indirectly) dueto the other person. We can see an example of this in the research on status characteris-tics theory. Kalkhoff et al. (2008) pointed out that in text-based VEs, the hypothesizeddisparities in influence due to status advantages are weaker than in video-based VEs. Theypoint out that this is problematic because if researchers use text-based VEs to study these



processes, they may falsely conclude that disparities due to status advantage have disap-peared and are no longer relevant in our culture.

External validity

Related to internal validity is external validity. One measure of the external validity of anexperiment is its ability to generalize from a sample to a broader population (Cook &Campbell 1979), a feature that is predicated upon its representativeness of ‘‘real-world’’situations. As mentioned earlier, Blascovich and colleagues (Blascovich et al. 2002;McCall & Blascovich 2009) have taken up this issue at length. A second type of externalvalidity is the ability of an experiment to generate results that are generalizeable acrosspopulations and settings. This second type of external validity focuses on the interplaybetween theory and data, and how one informs the other. Theories, because they areabstract and general, are what provide explanations across populations and settings; indi-vidual studies do not because they are specific and tied to only a single population or set-ting (Berkowitz and Donnerstein 1982; Lucas 2003; Zelditch 1969). As such, being ableto connect a single study to a theory is what allows us to determine how well the studycan describe processes across populations or settings. This is precisely what is meant bythe second type of external validity. Lucas’s (2003) summary leads him to conclude thatthis aspect of a study’s external validity has the following two dimensions: ‘‘(1) the extentto which empirical measures accurately reflect theoretical constructs, [and] (2) whetherthe research setting conforms to the scope of the theory under test’’ (p. 236). An under-standing of copresence in a VE experiment grants us purchase on these two dimensions.

With respect to the first dimension, many have suggested that VE experiments offeradditional control over the instantiation of theoretical constructs compared to that seenwith more traditional lab settings (Blascovich et al. 2002; McCall & Blascovich 2009;Rashotte et al. 2005). Instructions, for example, can be pre-recorded and delivered to theresearch participant via a VE so that they are delivered the same way at every experimen-tal session. Similarly, the pre-recording or programming of a confederate’s actions wouldmean that each research participant would be exposed to the same stimulus introducedby the confederate (e.g. ‘‘gender,’’ ‘‘conformist,’’ ‘‘leader’’) in a similar fashion.

Since copresence affects the strength of responses, we might expect it to also be relatedto the variance of responses. Still unclear, however, is whether this claim is true. Ifcopresence is related to the extent that VE experiments offer greater control, then wemight expect that random error (captured in the variance of participant responses) wouldbe systematically related to copresence. That is, participants should be responding moresimilarly to one another at certain levels of copresence than at other levels.

Two studies that compared video to text conditions exemplify the need for furtherrefining how copresence relates to the accuracy of constructs instantiated in a VE. Recallthat copresence, all else being equal, tends to be higher in video than in text interactions.In the descriptives shown for a study presented by Kalkhoff et al. (2008, Table 1), twosets of baseline groups (men paired with men and women paired with women) haveslightly smaller standard deviations in the video than in the text conditions. However,Rashotte (2003, Tables 1 and 2) finds the opposite pattern; standard deviations are slightlysmaller in the text than video conditions.

The second external validity dimension is concerned with a theory’s scope condition, thedomain of phenomena to which a theory applies (Cohen 1989). When testing theoriesabout social processes – the effect of one person (or a group) on another person (or a group)– by definition we are implying that there is a non-zero level of copresence (as captured in



Allport’s 1954 definition of social psychology). In other words, a theory about a social pro-cess implies that a non-zero level of copresence is part of its scope condition. Unfortunately,this implicit assumption does not receive much attention in the design of sociological exper-iments and threatens external validity. As Lynch (1982) contends: ‘‘the validity of general-izations drawn from experimental data is limited by the validity of our a priori models of thebehavior under study, because these models guide our deliberate or inadvertent treatment ofbackground variables in sampling, experimental design, and data analysis.’’ (p. 225)

We can conduct a systematic test of the implications from ignoring this assumption byobserving the extent that copresence acts as a moderating variable in a theory’s predictedprocesses. Although not explicitly testing for copresence differences, there have beenexamples of attempts to understand empirical settings as moderating variables in well-established theories in sociological social psychology. Kalkhoff et al. (2008), as mentionedearlier, compared how video and text settings change the observed influence patterns pre-dicted by status characteristics theory. Collett and Childs (2011) looked at how a vignettedesign altered the social exchange outcomes seen in a comparable laboratory settingwhere participants shared a physical space with others who were presumably theirexchange partners. Rashotte (2003) compared the impressions formed about social eventsthat were described on videotape and text in an effort to uncover methodological consid-erations for research on affect control theory. The next step would be to begin explicitlyexamining the role of copresence in these comparisons between empirical settings.

Gap in the copresence literature

A major impediment to informing experimental research design in sociology with anunderstanding of copresence is that a standardized measure (or set of measures) forcopresence currently does not exist. Several researchers studying copresence in VEs havewritten calls to action with the intention of stirring a proper understanding of how to mea-sure the construct (e.g., Bailenson et al. 2005; Biocca et al. 2004). Yet, there are still a vari-ety of ways in which the construct is measured in experiments using VEs. Biocca andcolleagues (Biocca et al. 2001; Nowak and Biocca 2003), for example, advocate for the useof two separate self-report scales, one that gauges a user’s own copresence with a partner inthe interaction and a second that asks the user’s perception of the partner’s copresence withthe user. Bailenson and colleagues (e.g., Bailenson et al. 2003, 2005) have been focused onidentifying behavioral proxies for copresence, with the assumption that high levels ofcopresence will result in behaviors we would see in face-to-face situations.

Part of the reason why the gap exists could certainly be that the research surroundingcopresence and VEs is interdisciplinary (see Cavanagh 2007 for a similar statement aboutinternet research). Multiple, closed networks of researchers who disseminate findings inniche journals prevents the logical and linear progression of knowledge. Similarities inexperimental procedures across studies usually emerge within a system of interrelated state-ments about concepts (Troyer 2001); since the research around copresence is fragmented,this presents a formidable challenge. Perhaps a first step toward addressing this gap will befor researchers to make interdisciplinary linkages. This review has been one attempt.

Conclusion

A user’s copresence with others, a variable and subjective sense, in a VE shapes the extentthat known social processes unfold. The research revealing this proposition about VEshas grown, yet remained largely unrecognized to experimental sociologists, who are



increasingly using VEs to increase control over laboratory settings. Knowledge of how tovary copresence can help us as researchers reach the full potential of VEs. I reviewedhow we can manipulate copresence in VEs, and discussed practical applications of thisknowledge for experimental sociologists.

Linking research on copresence in VEs to the goals of experimental research in sociol-ogy is double-edged sword. On the one hand, making this interdisciplinary linkageaddresses a much needed understanding of how copresence can moderate social processesin sociology. On the other hand, the literature on copresence in VEs, like much of theother literature on technological communication, is already opaque due to disjointed con-tributions from multiple sources. Adding an additional source of contributions could verywell make the situation worse.

Some optimism remains. A review like this can make these issues and potential foradvancement salient. We already have researchers concerned with methodological differ-ences as moderators of social processes in sociology (some mentioned here), as well as inother fields. We now have a review that identifies precisely how copresence can producethese disparate findings in VEs. We also have a wide collection of empirical findings aboutcopresence itself. The most burdensome parts of the task at hand are already complete.

Short Biography

Celeste Campos-Castillo is a Ph.D. candidate in the Department of Sociology at the Uni-versity of Iowa. She conducts basic and applied research on trust in task groups, the socialdeterminants of health, and inequalities during computer-mediated communication. Sheis currently completing her NSF-funded dissertation research, which examines how pat-terns of trust in the patient-provider dyad contribute to health disparities. Beginning Fall2012, she will be a post-doctoral research fellow at Dartmouth College’s Institute forSecurity, Technology, and Society.

Notes

* Correspondence address: Celeste Campos-Castillo, W140 Seashore Hall, Iowa City, Iowa 52242, USA. E-mail:[email protected]

1 For more detailed descriptions of immersive VEs and the equipment required to render them, the reader is direc-ted to the following reviews: Blascovich et al. 2002; Brooks 1999; McCall and Blascovich 2009; Slater 2009.

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