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Journal of Anxiety Disorders 27 (2013) 398– 403

Contents lists available at SciVerse ScienceDirect

Journal of Anxiety Disorders

o conversations with virtual avatars increase feelings of socialnxiety?

ark B. Powersa,∗, Nicole F. Bricenoa, Robert Greshama, Ernest N. Jourilesa,aul M.G. Emmelkampb,c, Jasper A.J. Smitsa

Southern Methodist University, Dallas, TX, United StatesThe University of Amsterdam, The NetherlandsKing Abdulaziz University, Saudi Arabia

a r t i c l e i n f o

rticle history:eceived 27 August 2012eceived in revised form 1 March 2013ccepted 10 March 2013

eywords:irtual realityew technologyocial anxiety

a b s t r a c t

Virtual reality (VR) technology provides a way to conduct exposure therapy with patients with socialanxiety. However, the primary limitation of current technology is that the operator is limited to pre-programed avatars that cannot be controlled to interact/converse with the patient in real time. Thecurrent study piloted new technology allowing the operator to directly control the avatar (includingspeaking) during VR conversations. Using an incomplete repeated measures (VR vs. in vivo conversa-tion) design and random starting order with rotation counterbalancing, participants (N = 26) providedratings of fear and presence during both VR and in vivo conversations. Results showed that VR conver-sation successfully elevated fear ratings relative to baseline (d = 2.29). Participants also rated their fear

onversationearmmersion

higher during VR conversation than during in vivo conversation (d = 0.85). However, in vivo conversa-tion was rated as more realistic than VR conversation (d = 0.74). No participants dropped out and 100%completed both VR and in vivo conversations. Qualitative participant comments suggested that the VRconversations would be more realistic if they did not meet the actor/operator and if they were not inthe same room as the participant. Overall, the data suggest that the novel technology allowing real time

in VR

interaction/conversation

. Introduction

Social anxiety disorder (SAD) is a debilitating disorder thatffects approximately 12% of the United States population (Kesslert al., 2005). Currently the most researched and effective treat-ent for SAD is exposure-based cognitive behaviour therapy (CBT)

Hofmann & Smits, 2008; Powers, Sigmarsson, & Emmelkamp,008). However, given the feared situation in SAD involves inter-cting with or performing in front of other people, creating realisticxposure scenarios in clinical practice is challenging and notften achieved in clinical practice. Indeed, most therapists doot conduct any exposure therapy. For example, bibliotherapy,edication, dynamic therapy, and cognitive therapy are all more

ommonly used than exposure (Freiheit, Vye, Swan, & Cady, 2004;oisman, Warshaw, & Keller, 1999). Among the few therapists

hat utilize exposure therapy, they often rely on prescribing expo-

ures as homework (risking poor compliance) or, if time permits,eeting the patient at various locations to conduct exposure exer-

ises. These methods come with increased cost, ethical concerns,

∗ Corresponding author. Tel.: +1 2145945520.E-mail address: mbpowers@smu.edu (M.B. Powers).

887-6185/$ – see front matter © 2013 Elsevier Ltd. All rights reserved.ttp://dx.doi.org/10.1016/j.janxdis.2013.03.003

may prove useful for the treatment of social anxiety in future studies.© 2013 Elsevier Ltd. All rights reserved.

and difficulty controlling stimuli. In response to these concerns,researchers have developed alternative methods of exposure deliv-ery including over the internet and virtual reality exposure therapy(VRET) environments.

Anxiety treatment via the internet is helpful in reaching clientswho may otherwise not have access to trained exposure thera-pists (Carlbring et al., 2006; Carlbring et al., 2007; Lange et al.,2000; Lange, Van de Ven, Schrieken, & Emmelkamp, 2001; Langeet al., 2003). However, exposure is still limited to email/texting, awebcam where the therapist still needs to recruit confederates tointeract with, or an avatar that is not fully controlled in real timeby the therapist. Exposure through virtual reality has proven quitesuccessful across the anxiety disorders (Emmelkamp, 2005; Opriset al., 2012; Powers & Emmelkamp, 2008). A noteworthy benefit ofusing (VRET) is that it easily enables the therapist to manipulatethe feared situation and environment for public speaking anxiety(Anderson, Zimand, Hodges, & Rothbaum, 2005; Safir, Wallach, &Bar-Zvi, 2012; Wallach, Safir, & Bar-Zvi, 2009). In addition, VRET isconsidered more tolerable and acceptable to patients (Emmelkamp,

2005). Unfortunately, VRET technology does not yet allow thepatient to have conversations with the people (avatars) in the vir-tual environments in real time. For example, it is possible to heara voice over the internet while looking at an avatar. However, the

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vatar’s lips and movements/gestures are not in sync with the voice.rials to date have only included exposure to such avatars with lim-ted response options and speech either through typing or auditoryutput without linked facial movement and expressions (Harris,emmerling, & North, 2002; Klinger et al., 2005). This is unfortunateiven findings that show involvement in the VRET is crucial for suc-ess (Price, Mehta, Tone, & Anderson, 2011) and that involvements enhanced when avatars are visually responsive to the participantGarau, Slater, Pertaub, & Razzaque, 2005). Thus, interactive real-ime conversations still need to be conducted in vivo; VRET woulde far more useful for treating SAD if the therapist were able to alsoanipulate the avatar to converse with the patient in real time.

his would allow therapists to conduct in-session exposure exer-ises aimed at reducing patients’ fears of performance situationsnvolving social interaction and conversation.

Two recent studies piloted new virtual reality (VR) technology inhe context of training women to resist unwanted sexual advances.ouriles, McDonald, Kullowatz, Rosenfield, Gomez, and Cuevas2009) randomized 62 undergraduate students to a standard face-o-face role-play with a male actor or a virtual conversation with

male avatar (fully controlled by the actor) in a virtual environ-ent. Consistent with predictions, VR conversations were rated asore realistic and participants showed greater negative affect com-

ared to the face-to-face condition. Similar findings were observedn the second study of 48 women randomized to VR or face-to-ace conditions (Jouriles, Simpson Rowe, McDonald, Platt, & Gomez,011). Although preliminary, findings from these studies supporthe validity of virtual conversation for assessing undergraduateomen’s reactions in sexually threatening situations and under-

core the potential utility of this VR technology for simulating socialnteraction situations. However, this technology has not yet beenxtended to the treatment of social anxiety. As a first step in thisrocess, we tested the ability of this technology to elicit social anx-

ety in a college population.This proof-of-concept pilot study investigated the use of VR

nteractive conversation technology in college populations. Athis stage, we define “proof” as activation of the fear structureoperationalized as SUDs during VR conversation). Although wenticipated SUDs to be higher in the in vivo comparison condition,e wanted to see if VR conversation significantly raised SUDs rel-

tive to baseline. Participants discussed controversial topics with actor/operator in either VR or in vivo environments. Based on previ-us findings (Barlow, Leitenberg, Agras, & Wincze, 1969; Dyckman

Cowan, 1978; Emmelkamp & Wessels, 1975; Jouriles et al., 2009;ouriles et al., 2011; Litvak, 1969; Powers & Emmelkamp, 2008;herman, 1972; Watson, Mullett, & Pillay, 1973), we expected that:a) SUDs would be significantly higher during VR conversation thant baseline, (b) participants would report higher anxiety during then vivo conversation compared to the VR conversation, and (c) par-icipants would rate the in vivo conversation as more realistic thanhe VR conversation.

. Methods

.1. Participants

Participants were recruited from an undergraduate course insychology, and received extra credit for their participation in thetudy. The 26 undergraduate participants were primarily female73.1%). Most were Non-Hispanic White (76.9%, 11.5% Black, 7.7%ispanic, 3.8% Asian) with a mean age of 20.42 (SD = 0.45). Partic-

pants in this trial scored similar to college students in previoustudies on measures (described below) of social anxiety (LSAS

= 36.12, SD = 18.61) and general anxiety (STAI Trait M = 35.46,D = 7.04). However, participants did not complete a structurediagnostic interview.

Disorders 27 (2013) 398– 403 399

2.2. Design

All study participants took part in both an “In Vivo” and a “VR”conversation condition. The order in which a participant engagedin one conversation before the other (i.e. In Vivo then VR or VRthen In Vivo) was determined by counterbalancing the conditionorder prior to participants’ assignment. When a participant arrivedfor their scheduled time they were assigned to the next availablecondition. Half of the participants (n = 13) engaged in the In Vivoconversation first and the other half (n = 13) participated in the VRconversation first.

2.3. Procedure

Procedures were modified (to include controversial topics) fromprevious trials (Jouriles et al., 2009; Jouriles et al., 2011; Smits,Powers, Buxkamper, & Telch, 2006). All procedures were approvedby the university Institutional Review Board. Upon arrival, par-ticipants signed informed consent, after which they completed abattery of self-report measures. After completing the measuresthe participants were told they would be engaging in two 5-min conversations. They were instructed that they could stopthe conversations at any time if they became too uncomfortable.Depending on their assignment into the rotated order of conver-sation, they were informed they would be doing either In Vivofollowed by VR or VR followed by In Vivo. In Vivo was explainedto the participants as; “Right here, just as we are now,” and VRas “In virtual reality, where we will talk to each other, but whilewearing ‘this’ headset and ‘these’ earphones.” Participants wereinstructed by the facilitator, a male research staff member withgraduate training (blind to study hypotheses), would pick the topicof both conversations, leave the room for 3 min so that they mightprepare any thoughts on the topic, then reenter, at which point theconversation would begin. Although participants were not givenspecifics regarding the facilitator’s dialogue, they were told theywould be asked their opinions on a topic, as well as questionsregarding any opinions or conclusions they might express. All ses-sions were video recorded for adherence coding. The adherencecoding form was adapted from our previous trials in prolongedexposure therapy for posttraumatic stress disorder and exposurewith ritual prevention for obsessive compulsive disorder (Foa et al.,2013; Gilboa-Schechtman et al., 2010). The form included 2 ques-tions on essential elements, 6 questions on essential but not uniqueelements, and 2 questions on adherence overall. The rater thentook into account the Likert items to make a categorical adherencerating.

After providing a baseline fear rating (0 [no fear] to 100 [mostfear imaginable]), participants were given the list of possible con-versation topics for the In Vivo and VR conversations (same sexmarriage, abortion, Iraq war, Evolution/Creationism in schools,torture to gather intelligence, homosexuals in the military, mostembarrassing moment). The topics were similar to those used inprevious social anxiety studies (Smits et al., 2006). To increasethe likelihood of participant engagement in a dialogue with thefacilitator, topics were contemporary and relatively controversial.Participants were instructed to rate their highest predicted level offear during a 5-min conversation for each of the seven topics, withratings to be given for conversation in both the In Vivo and in the VRenvironment. The topic with the highest predicted SUDs rating wasselected as the topic of conversation. The same topic was used forboth conversations. In the event of equivalent ratings across multi-

ple topics the facilitator exercised his discretion in selecting a topic.The participant was then given the topic and the facilitator left theroom for 3 min while the participant prepared their thoughts onthe topic.

400 M.B. Powers et al. / Journal of Anxiety Disorders 27 (2013) 398– 403

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Fig. 1. Participant and therapist converse in VR.

In the VR conversation condition the facilitator introduced theR Head Mounted Display and headphones, and instructed/aided

he participant in putting them on (see Fig. 1).In the In Vivo condition the facilitator simply sat to the left of

he participant on a couch. Their distance from the participant wasatched to the distance depicted in the VRET scene.In both the VR and In Vivo conditions, the facilitator began tim-

ng the conversation and stated, “Okay, now we’re going to have conversation about (selected topic inserted). To begin, whato you personally think about ?” During the course of the con-ersation the participant was asked several open-ended questionsrom a predetermined list to ensure the conversation would con-inue for the 5-min duration (e.g. “And why do you believe that?ow did you come to believe that?). In addition, the facilitator was

nstructed to voice a viewpoint in opposition to whatever positionhe participant chose for a given topic. After 5-min the conversa-ion with the participant was stopped, and they were asked to rateheir highest level of fear during the 5 min conversation. Immedi-tely after completing the first conversation, procedures began forhe second conversation (i.e. 3-min for the participant to prepareheir thoughts on the topic). After completing both conversations,articipants were thanked for their participation, and the sessionas concluded. Given the aim of this study, participants were also

nvited to comment on the experience after debriefing.

.4. Materials

The hardware and software used in this study was the same ashat used in previous studies of this technology (Jouriles et al., 2009;ouriles et al., 2011). The VR conversation was facilitated throughhe use of a virtual avatar interacting with the participant in a vir-ual environment (VE). The Virtual environment was created from

odification (mod) templates based around the video game Half-ife 2®. The avatar was a modified character from the game, andesigned to look like a typical male university student. The virtualnvironment was designed to look like a college dorm or apart-ent bedroom (e.g. bed, television, movie posters, computer desk,

ouch). From the participants virtual perspective the avatar waseated to their left on a couch (same position as in vivo condition)see Fig. 2).

The participant interacted with the virtual environment via these of an eMagine z800 stereovision head mounted display (HMD).he HMD allowed the participant to view the virtual environment.urthermore, head tracking hardware built into the HMD allowed

he VR software to sense the participants head movements anddjust their view accordingly, thus giving participants fully immer-ive control of where and what they viewed within the virtualnvironment.

Fig. 2. VR conversation avatar.

In addition to the HMD, in the VR conversation condition,the participant wore a pair of over-the-ear noise cancel-lation headphones. The facilitator used a Microsoft LifechatLX-2000 microphone headset to speak with the participant. Themicrophone-headphone communication was relayed through theVR software, so that as the facilitator spoke, the virtual avatarsmouth would move thereby approximating the look of normalspeech. Furthermore, the facilitator, via keyboard command, wasalso able to change the avatar’s facial expressions (e.g. happy, sad,angry), as well as a number of gestures (e.g. nodding, pointing atthe participant, shrugging, throwing his hands in air). All hardwareand software was run through a personal computer using a PentiumIV® CPU, 512 megabytes of RAM, and a 6800 Graphics processor(Jouriles et al., 2009).

2.5. Measures

2.5.1. Liebowitz Social Anxiety Scale (LSAS)The LSAS is a widely used 24-item interviewer-rated instrument

that assesses fear and avoidance of social situations. Participantsrate fear items on a 4-point scale ranging from 0 (none) to 3 (severe).Likewise, avoidance is also rated on a 4-point scale ranging from0 (never) to 3 (usually). The LSAS takes approximately 20–30 minto complete. The LSAS shows good reliability ( ̨ = 0.81–0.92) andvalidity (Cox, Ross, Swinson, & Direnfeld, 1998; Safren et al., 1999).Scores may be interpreted as: 55–65 Moderate, 65–80 Marked,80–95 Severe, >95 Very Severe. The mean for participants withsocial anxiety disorder is 67.2 (SD = 27.5) (Heimberg et al., 1999).

2.5.2. State-Trait Anxiety Inventory (STAI)The state-trait anxiety inventory is a 20-item self-report mea-

sure of state and trait anxiety (Spielberger, Gorsuch, Lushene,Vagg, & Jacobs, 1983). The measure takes about 10 min to com-plete. The STAI shows good reliability ( ̨ = 0.86–0.95) and validity(Spielberger et al., 1983). Interpretation of scores: Adults (M = 35SD = 10), Generalized Anxiety Disorder (47–61), Panic Disorderwith Agoraphobia (51–54), Panic Disorder (44–46).

2.5.3. Subjective Units of Disturbance (SUDs)The SUDs scale is a measure of subjective anxiety (0 = No Dis-

turbance to 100 = Most Disturbance) that was rated by participantsafter the conversations (Wolpe, 1958; Wolpe, 1990). Participantsreported the highest level that their SUDs reached.

2.5.4. Presence/immersion

The measure of presence/realism was a 9-item immersion ques-

tionnaire used in our two previous similar studies with womenresisting unwanted sexual advances (Jouriles et al., 2009; Jourileset al., 2011). Items were rated on a 0 (Not at All) to 5 (Very Much)

M.B. Powers et al. / Journal of Anxiety

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cale (e.g. Did you ever feel that you might actually be defendingour position to a stranger? Were you involved in the role playo the extent that you lost track of time?, etc.). The scale showedxcellent reliability with this sample (Cronbach’s ̨ = 0.82; Guttmanplit-half = 0.84).

. Results

There were no dropouts and no data missing in this small pilotrial. Thus all results represent completer analyses. Overall, fearatings ranged between 5 and 90 and correlations between theutcome measures ranged between −0.49 and 0.59. None of theseorrelations were significant except for the correlation between theated presence in the VR and in vivo conditions (r = 0.53, p = 0.006).

.1. Randomization check

ANOVAs showed there were no significant differences in partici-ants randomized to VR then in vivo compared to those randomizedo in vivo then VR (age p = 0.42, LSAS total p = 0.14, VR presence rat-ng p = 0.92, in vivo presence rating p = 0.67, baseline SUDs p = 0.81,R peak SUDs p = 0.42, & in vivo peak SUDs p = 0.71).

.2. Order effects

An ANOVA showed there was no main effect for order (VR firstr in vivo first; F(1,25) = 0.17, p = 0.68) or condition by order inter-ction (F(1,24) = 1.35, p = 0.26).

.3. Fear ratings

Hypothesis (a) paired samples t-tests and Fig. 3 show thatonsistent with prediction, participants rated their peak fear signif-cantly higher during VR conversation (M = 38.46, SD = 16.78) thant baseline (M = 16.73, SD = 11.99, t(25) = 8.26, p = 0.000, d = 2.29).ypothesis b) Contrary to prediction, participants rated their peak

ear significantly higher during conversations in the VR condi-ion (M = 38.46, SD = 16.78) compared to the in vivo conditionM = 29.23, SD = 10.36, t(25) = 3.08, p = 0.005, d = 0.85).

.4. Presence (realism) ratings

Hypothesis (c) Consistent with prediction, a paired samples t-est showed that participants rated conversations as significantly

ore realistic (presence) in vivo (M = 29.35, SD = 5.73) compared ton VR (M = 26.27, SD = 5.58, t(25) = 2.67 p = 0.013, d = 0.74).

Disorders 27 (2013) 398– 403 401

3.5. Feasibility, acceptability/tolerability, and qualitativeresponses

No participants dropped out of the trial early and 100% com-pleted both conversations. Participants comments after debriefingincluded: (a) the VR condition would be enhanced by having thefacilitator/actor sit in another room rather than controlling the VRfrom the couch next to the participant, (b) realism and fear would begreater if participants also did not meet the facilitator/actor beforethe conversation in VR, and (c) the controversial conversation wasalways easier the second time through the same topic (suggesting abetween-subjects design in the future). However, post hoc analysiswith a paired samples t-test suggested that fear ratings were stillsignificantly higher in the VR condition when only analysing thefirst conversations (p = 0.024). Also, a post hoc paired samples t-testshowed enhanced fear activation was not due solely to differencesin predicted fear between the VR (M = 34.36) and in vivo (M = 31.91)conditions (t = −0.88, p = 0.405). Finally, 10% of videos (n = 3) wereobserved for adherence to the pre-determined probes stated ear-lier. Ratings suggested that actor performance was consistent inboth the VR and In vivo conditions.

4. Discussion

Virtual reality technology increases access to exposure therapyfor patients with social anxiety. However, the primary limitation ofcurrent technology is that the operator is limited to pre-programedavatars that cannot be controlled to interact/converse with thepatient in real time. The current study piloted new technologyallowing the operator to directly control the avatar (includingspeaking) during VR social interactions. We used a within-subjectsincomplete repeated measures design with random starting orderwith rotation counterbalancing. Results showed that: (a) in vivoconversation was rated as more realistic than VR conversation,(b) fear ratings were higher during VR conversation compared toin vivo conversation, (c) no participants dropped out, and 100%completed both VR and in vivo conversations, and (d) qualitativeparticipant comments suggested that the VR conversations wouldbe more realistic if they did not meet the actor/operator and if theywere not in the same room as the participant.

Although in vivo conversation was rated as more realistic, par-ticipants reported higher fear ratings during the VR conversationcondition. Previous studies suggest that for reducing anxiety withexposure therapy, fear ratings are more predictive of efficacy thanrealism ratings (Foa & Kozak, 1986; M. Krijn, P. M. G Emmelkamp,R. Biemond, C. de Wilde de Ligny, M. J. Schuemie, & C. A. P. G. vander Mast, 2004; M. Krijn, P. M. G Emmelkamp, R. P. Olafsson, & R.Biemond, 2004; Powers & Emmelkamp, 2008; Price et al., 2011).Realism or presence is the extent to which one interprets the vir-tual environment as if it were real (Lee, 2004). Consistent withour findings, studies that have manipulated presence found thatit did not significantly affect treatment outcome (M. Krijn, P. M. GEmmelkamp, R. Biemond, et al., 2004; M. Krijn, P. M. G Emmelkamp,R. P. Olafsson, et al., 2004; Price & Anderson, 2007; Price et al., 2011).We can only speculate why fear ratings were higher in the VRconversation. Potential reasons could include: context (e.g. partyatmosphere vs couch in psychology department; greater activa-tion of the fear structure through a higher number of fear relevantstimuli), discomfort of simply being in any VR environment underany circumstance, less prior experience with the avatar vs. the actor(actor also conducted consent), or other reasons. Future studies

may help clarify why fear ratings are higher in VR compared toin vivo conversations. The dropout and completion rates are alsoencouraging for further development of this technology for socialanxiety applications. These initial pilot data are encouraging for

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xposure applications. In fact, if these findings are replicated andxtended, VR exposure could even prove more effective as a clinicalool than in vivo exposure.

Several limitations deserve comment. First, participants wereot selected based on social anxiety scores for this feasibility pilottudy. Future studies should determine if realism and fear ratingseneralize to those with high social anxiety. Second, participantstated that presence would be enhanced if they did not meet theacilitator/actor controlling the avatar prior to the conversation andf the actor also controlled the avatar from another room. Althoughhe participants reported that the noise cancellation headphonesnd head mounted display were effective, they were still aware ofhe presence of the actor on the couch next to them and that thishought was at times distracting from the realism of the VR conver-ation. Third, our small sample does not permit analysis of multipleimensions of presence (spatial presence, involvement, and real-ess) (Price et al., 2011). Future studies could help determinehich dimensions are enhanced through avatar interaction. Fourth,

his study does not indicate if real time interaction is superior totandard VRET for social anxiety. Future studies should compareRET with and without real time avatar interaction to determine

he relative efficacy. Fifth, participants were given course creditased on their participation. Thus, finding a 100% completion rateay not generalize to other populations. Sixth, although the actoras instructed to only use facial expressions, gestures, and gaze

onsistent with the avatar condition, this control was not verified.everal lines of research suggest the importance of gestures, facialxpressions, gaze, and mimicry in social anxiety (J. N. Vrijsen, W. G.ange, E. S. Becker, & M. Rinck, 2010; J. N. Vrijsen, W. G. Lange,. Dotsch, D. H. J. Wigboldus, & M. Rinck, 2010; Wieser, Pauli,rosseibl, Molzow, & Muhlberger, 2010). Future studies shouldlso code and rate in vivo actors on gestures and facial expres-ions to match the VRET condition. Seventh, although SUDs fearatings are often used as outcome data, future studies should incor-orate additional measures of distress (e.g. behavioural approach,sychophysiology, etc.). Eighth, although content choices for theonversation topics have been used previously (e.g. Smits et al.,006), future studies may help determine the optimal contenthoices for social anxiety exposures. Finally, participants only com-leted each conversation condition (VR & in vivo) once. Thus,abituation/extinction could not be measured.

Overall, the data suggest that the novel technology allow-ng real time interaction/conversation in VR may prove usefulor the treatment of social anxiety in future studies. Futuretudies should include participants with high social anxiety,ot have the participant meet the actor/therapist prior to theession, and have the therapist control the avatar from a differentoom.

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