Time to Smile: How Onset Asynchronies Between Reciprocal Facial Expressions Influence the Experience of Responsiveness of a Virtual Agent

Human social interactions are highly coordinated in time and involve the reciprocal exchange of facial emotional expressions. While timing has been identified as an important factor in social communication via gaze or speech, so far there has been no systematic investigation on how the temporal delays in the exchange of facial emotional expressions between interactive partners influence the experience of responsiveness. In the present study, 40 participants were cued to direct a facial emotional expression (angry or happy) towards a virtual agent in front of them and the virtual agent would then react with a congruent facial expression. The temporal delay between the cue and the reaction was manipulated as an independent variable. Exact delays between facial expressions were determined based on the onset latencies of participants’ facial expressions measured via facial EMG (M. Zygomaticus and M. Corrugator). Ratings of experienced responsiveness of the virtual agent were collected as a dependent measure. Using a linear mixed effect model in a growth curve analysis revealed that experienced responsiveness peaked at delays around 700 ms. Moreover, experienced responsiveness at shorter temporal delays was higher when happy versus angry facial expressions were exchanged, while the reversed pattern was found at longer delays. Our results demonstrate a crucial role of timing in non-verbal communication, suggesting that temporal relations between facial expressions are processed as social information. Furthermore, our results can inform the implementation of virtual social interactions

Face masks reduce interpersonal distance in virtual reality

During the COVID-19 pandemic several behavioral measures have been implemented to reduce viral transmission. While these measures reduce the risk of infections, they may also increase risk behavior. Here, we experimentally investigate the influence of face masks on physical distancing. Eighty-four participants with or without face masks passed virtual agents in a supermarket environment to reach a target while interpersonal distance was recorded. Agents differed in wearing face masks and age (young, elderly). In addition, situational constraints varied in whether keeping a distance of 1.5 m required an effortful detour or not. Wearing face masks (both self and other) reduced physical distancing. This reduction was most prominent when keeping the recommended distance was effortful, suggesting an influence of situational constraints. Similarly, increased distances to elderly were only observed when keeping a recommended distance was effortless. These findings highlight contextual constraints in compensation behavior and have important implications for safety policies

CD40 Ligand and Autoantigen Are Involved in the Pathogenesis of Low-Grade B-Cell Lymphomas of Mucosa-Associated Lymphoid Tissue

Low-grade MALT-type lymphomas are malignancies of mucosal marginal-zone B cells and preceded by reactive inflammatory lymphoid tissue. Experimental observations suggest that antigen and CD40 Ligand act during cognate T/B cell interaction and are crucial for germinal center B-cell maturation generating marginal-zone B cells. To investigate the mechanisms underlying the development of extranodal MALT-type lymphomas, the immunoglobulin receptor was sequenced and analyzed for antigen specificity using heterohybridoma technology. Furthermore, CD40 ligand expression was evaluated by immunohistochemistry and by semiquantitative RT-PCR, and ligand binding to the CD40 of tumor B cells was studied using the CD40 system. Hypermutations were found in low-grade lymphomas throughout CDR1- CDR3 suggestive of positive selection through their antigen receptor. Different VH families were used and more than 69% of tumor immunoglobulins bound different mucosal antigens. CD40L expression was found in the tumor marginal zone in substantial amounts. The in vitro proliferation response of all low-grade MALT-type lymphomas was dependent on anti-CD40- mediated signals and cytokines. Our data provide evidence that autoantigen as well as the CD40L expressed by activated nonneoplastic T cells may drive the evolution of low-grade MALT-type lymphomas either directly or by paracrine mechanisms and that antigen may contribute to lymphoma pathogenesis

Interpersonal Distance During Real-Time Social Interaction: Insights From Subjective Experience, Behavior, and Physiology

Physical distance is a prominent feature in face-to-face social interactions and allows regulating social encounters. Close interpersonal distance (IPD) increases emotional responses during interaction and has been related to avoidance behavior in social anxiety. However, a systematic investigation of the effects of IPD on subjective experience combined with measures of physiological arousal and behavioral responses during real-time social interaction has been missing. Virtual Reality allows for a controlled manipulation of IPD while maintaining naturalistic social encounters. The present study investigates IPD in social interaction using a novel paradigm in Virtual Reality. Thirty-six participants approached virtual agents and engaged in short interactions. IPD was varied between 3.5 and 1 m by manipulating the distance at which agents reacted to the participant's approach. Closer distances were rated as more arousing, less pleasant, and less natural than longer distances and this effect was significantly modulated by social anxiety scores. Skin conductance responses were also increased at short distances compared to longer distances. Finally, an interaction of IPD and social anxiety was observed for avoidance behavior, measured as participants' backward motion during interaction, with stronger avoidance related to close distances and high values of social anxiety. These results highlight the influence of IPD on experience, physiological response, and behavior during social interaction. The interaction of social anxiety and IPD suggests including the manipulation of IPD in behavioral tests in Virtual Reality as a promising tool for the treatment of social anxiety disorder

Social Presence as a Moderator of the Effect of Agent Behavior on Emotional Experience in Social Interactions in Virtual Reality

Background: Exposure therapy involves exposure to feared stimuli and is considered to be the gold-standard treatment for anxiety disorders. While its application in Virtual Reality (VR) has been very successful for phobic disorders, the effects of exposure to virtual social stimuli in Social Anxiety Disorder are heterogeneous. This difference has been linked to demands on realism and presence, particularly social presence, as a pre-requisite in evoking emotional experiences in virtual social interactions. So far, however, the influence of social presence on emotional experience in social interactions with virtual agents remains unknown. Objective: We investigated the relationship between realism and social presence and the moderating effect of social presence on the relationship between agent behavior and experienced emotions in virtual social interaction. Methods: Healthy participants (N = 51) faced virtual agents showing supportive and dismissive behaviors in two virtual environments (short interactions and oral presentations). At first, participants performed five blocks of short one-on-one interactions with virtual agents (two male and two female agents per block). Secondly, participants gave five presentations in front of an audience of 16 agents. In each scenario, agent behavior was a within subjects factor, resulting in one block of neutral, two blocks of negative, and two blocks of positive agent behavior. Ratings of agent behavior (valence and realism), experience (valence and arousal), and presence (physical and social) were collected after every block. Moderator effects were investigated using mixed linear models with random intercepts. Correlations were analyzed via repeated measures correlations. Results: Ratings of valence of agent behaviors showed reliable relationships with experienced valence and less reliable relationships with experienced arousal. These relationships were moderated by social presence in the presentation scenario. Results for the interaction scenario were weaker but potentially promising for experimental studies. Variations in social presence and realism over time were correlated but social presence proved a more reliable moderator. Conclusion: Our findings emphasize the role of social presence for emotional experience in response to specific agent behaviors in virtual social interactions. While these findings should be replicated with experimental designs and in clinical samples, variability in social presence might account for heterogeneity in efficacy of virtual exposure to treat social anxiety disorder

Angry facial expressions bias towards aversive actions

Social interaction requires fast and efficient processing of another person’s intentions. In face-to-face interactions, aversive or appetitive actions typically co-occur with emotional expressions, allowing an observer to anticipate action intentions. In the present study, we investigated the influence of facial emotions on the processing of action intentions. Thirty-two participants were presented with video clips showing virtual agents displaying a facial emotion (angry vs. happy) while performing an action (punch vs. fist-bump) directed towards the observer. During each trial, video clips stopped at varying durations of the unfolding action, and participants had to recognize the presented action. Naturally, participants’ recognition accuracy improved with increasing duration of the unfolding actions. Interestingly, while facial emotions did not influence accuracy, there was a significant influence on participants’ action judgements. Participants were more likely to judge a presented action as a punch when agents showed an angry compared to a happy facial emotion. This effect was more pronounced in short video clips, showing only the beginning of an unfolding action, than in long video clips, showing near-complete actions. These results suggest that facial emotions influence anticipatory processing of action intentions allowing for fast and adaptive responses in social interactions

Protective Effector Memory CD4 T Cells Depend on ICOS for Survival

Memory CD4 T cells play a vital role in protection against re-infection by pathogens as diverse as helminthes or influenza viruses. Inducible costimulator (ICOS) is highly expressed on memory CD4 T cells and has been shown to augment proliferation and survival of activated CD4 T cells. However, the role of ICOS costimulation on the development and maintenance of memory CD4 T cells remains controversial. Herein, we describe a significant defect in the number of effector memory (EM) phenotype cells in ICOS−/− and ICOSL−/− mice that becomes progressively more dramatic as the mice age. This decrease was not due to a defect in the homeostatic proliferation of EM phenotype CD4 T cells in ICOS−/− or ICOSL−/− mice. To determine whether ICOS regulated the development or survival of EM CD4 T cells, we utilized an adoptive transfer model. We found no defect in development of EM CD4 T cells, but long-term survival of ICOS−/− EM CD4 T cells was significantly compromised compared to wild-type cells. The defect in survival was specific to EM cells as the central memory (CM) ICOS−/− CD4 T cells persisted as well as wild type cells. To determine the physiological consequences of a specific defect in EM CD4 T cells, wild-type and ICOS−/− mice were infected with influenza virus. ICOS−/− mice developed significantly fewer influenza-specific EM CD4 T cells and were more susceptible to re-infection than wild-type mice. Collectively, our findings demonstrate a role for ICOS costimulation in the maintenance of EM but not CM CD4 T cells

Public speaking training in front of a supportive audience in Virtual Reality improves performance in real-life

Abstract Public speaking is a challenging task that requires practice. Virtual Reality allows to present realistic public speaking scenarios in this regard, however, the role of the virtual audience during practice remains unknown. In the present study, 73 participants completed a Virtual Reality practice session while audience was manipulated to be supportive or unsupportive or presentations were practiced without audience. Importantly, following the virtual practice, participants held the presentation during a real university course via Zoom. We measured emotional experience, self-efficacy, and the subjective evaluation of performance at baseline, after VR practice, and after the real presentation. Additionally, participants’ performance in the real presentation was evaluated by instructors (blinded to condition). Supportive in contrast to unsupportive audiences led to more positive believes about one’s own performance, while there were no changes in beliefs in the group without audience. Importantly, practice in front of a supportive compared to unsupportive audience resulted in a more positive evaluation of speaker confidence in real-life public speaking as rated by the instructors. These results demonstrate an impact of virtual social feedback during public speaking on subsequent subjective performance evaluation. This may increase self-confidence resulting in actual improved public speaking performance in real-life