In the domain of interpersonal communication, the eye region has a vital role. Specifically, the pupil has an essential signalling function, reflecting different cognitive and affective states. The...Show moreIn the domain of interpersonal communication, the eye region has a vital role. Specifically, the pupil has an essential signalling function, reflecting different cognitive and affective states. The colours of the iris, surrounding the pupil, varies largely among human beings. Although studies are conducted on how the colour of the iris influences gaze perception, none have yet investigated the role of iris brightness on the perception of pupil size changes. It is furthermore known that pupil size changes affect interpersonal trust: while dilating pupils lead to a signal of trust, constricting pupils convey untrustworthiness. Nonetheless, the role of iris brightness within this process remains unknown. Moreover, there is evidence for the role of empathy within the processing of pupil size changes. Therefore, the current study explored whether iris brightness affects the perception of pupil size changes. Also, the study examined whether the brightness of the iris in dilating and constricting pupils affected the reported trustworthiness of virtual partners while controlling for the participants’ level of empathy. Fifty-one participants were included in the analysis. These participants were shown animations of a virtual partner with either dark or light irises and dilating, static or constricting pupils. In the Perception of Pupil Movement-task, they were asked: ‘Do you see movement?’. In the Trust-Game Task, they were asked: ‘Would you trust this person to donate money to a charity on behalf of you?’. The results showed that iris brightness affected the perception of pupil size changes. In stimuli with brighter irises, it was easier for participants to detect changes in the size of the pupil. Participants showed less trust when exposed to stimuli representing dilating pupils than static pupils in both light and dark irises while controlling for the individual’s level of empathy. The decreased trust in the constricting stimuli compared to the static stimuli in light and dark irises was in line with expectations. In the dark irises, there was no difference in trust scores between dilating and constricting pupils. In the stimuli representing light irises, on the other hand, there was an effect. This research found no evidence that more empathetic people perceive these subtle cues in eye contact better than less empathetic people. Our results underline the interplay of iris brightness and pupil size changes in monetary decision making and interpersonal communication, specifically regarding perceived trustworthiness.Show less
The introduction of embodied agents, including robots and avatars, to public institutions, educational settings and health care influences modern society (Smids et al., 2019; Wisskirchen et al.,...Show moreThe introduction of embodied agents, including robots and avatars, to public institutions, educational settings and health care influences modern society (Smids et al., 2019; Wisskirchen et al., 2017) As culture affects people’s perception and thinking (Kastanakis & Voyer, 2014; Triandis & Suh, 2002), it is important to study cross-cultural differences in attitudes towards embodied agents ultimately influencing interaction and acceptance rates. Japanese advanced robotic technology (Šabanović, 2014) serves as a prime example of possible variance in attitudes between Eastern and Western countries. The present study explored the influence of cultural backgrounds on implicit and explicit attitudes towards robots as well as the effect of human-likeness on the positivity of attitudes. Native Dutch and Japanese (n=80) participants were recruited at Leiden University and using the recruitment platform CrowdWorks in Japan. We hypothesized that both cultures would show a stronger implicit preference for humans over robots and more positive implicit evaluations of humanoid compared to mechanical robots. Furthermore, we assumed to replicate a previous study (MacDorman et al., 2009) concluding that, against common belief, Japanese participants would show no significant difference in robot acceptance compared to Western participants. The present quantitative study contains the Implicit Association Test (IAT) and the Negative Attitudes Towards Robots Scale (NARS). Our results show no significant cultural differences in the observed preference of humans over robots. Humanoids are preferred over mechanical robots while there are no differences in implicit robot evaluations between cultures. Japanese participants scored significantly lower on average on the NARS, showing more positive explicit attitudes towards robots. The validity of the interpretation of the results is lowered due to an unbalanced sample in age, gender and occupational level.Show less
Mimicry has been researched regarding how it relates to the emotional contagion and therefore how it leads to feelings of empathy in others. Autonomic mimicry leads to synchronized physiological...Show moreMimicry has been researched regarding how it relates to the emotional contagion and therefore how it leads to feelings of empathy in others. Autonomic mimicry leads to synchronized physiological processes between two individuals, supposedly to create a feeling of connectedness and trust. Blush is a rarely investigated part of autonomic mimicry, a kind of physiological mimicry in humans that is not consciously controlled. Blushing has been associated with trustworthiness, a fundamental component to establish empathy. Previous research has shown that individuals who blush are perceived as more trustworthy and following the research on the emotional contagion, blush mimicry should have a similar effect. This study investigated whether individuals mimic a blushing Virtual Character (VC) and whether mimicking blushing establishes feelings of trust for a VC. Trustworthiness is investigated using a trust game, blushing is measured with skin temperature. T-tests were used to investigated whether individuals mimic blushing expressions of the VC, which resulted in inconclusive findings. Linear regression analyses were used to predict trustworthiness from participants’ blush. Blushing mimicry did not increase investment in the trust game. This result indicates that the mimicry itself might not be the basis of feelings of trust in others, despite previous findings. Perceiving and mimicking blushing might provoke different reactions from different individuals. Additionally, blush is triggered by emotions like embarrassment and guilt in social situations, which could be distorted by using VCs. Limitations include the lacking social context with the VC, the neutral content of the stories, and the sample size. Future research should investigate responses of individuals to VCs and control for external factors of facial redness.Show less
The human eye, due to its unique morphology, is central for social interactions. Eye contact and mutual eye gaze are important to infer other’s emotions and to share experiences. In particular,...Show moreThe human eye, due to its unique morphology, is central for social interactions. Eye contact and mutual eye gaze are important to infer other’s emotions and to share experiences. In particular, pupillary changes, dilation and constriction, provide implicit cues to infer internal states of an interacting partner: when one experiences pleasant feelings, pupils dilate. Individuals with larger pupils are evaluated as more friendly, attractive, and trustworthy than those with smaller pupils. During human interactions changes in pupil diameter synchronize, a phenomenon called pupil mimicry. In particular, dilation mimicry correlates with increased perceived trustworthiness. Aim of the hereby research is to further investigate the relationship between pupil mimicry and trust. To do so, we conducted an experiment in which participants listened to a series of virtual characters narrating neutral stories while changes in there pupil diameter were recorded via an eye-tracker, allowing us to assess the presence of pupil mimicry by participants. A questionnaire after each interaction, in addition to an investment game were exploited to measure level of trust. A simple linear regression analysis was conducted to investigate whether pupil mimicry is a predictor for trust, selecting cases by neutral stories. Despite our predictions -based on previous studies-, results proved our hypothesis wrong showing non-significant results for three neutral stories. Results were significant concerning two stories but showing the opposite trend than the expected one. Within the discussion session, limitations of the study which might explain such results will be exposed.Show less
People with high social anxiety (HAs) mimic less than people with low social anxiety (LAs). I investigated whether this effect is the same for different types of motor behaviors, namely smiling and...Show morePeople with high social anxiety (HAs) mimic less than people with low social anxiety (LAs). I investigated whether this effect is the same for different types of motor behaviors, namely smiling and nodding; and whether there is a difference between the groups in the spontaneous displays of these behaviors. The data of 50 female and 12 male university students were analyzed. The participants completed the Liebowitz Social Anxiety Scale (LSAS) and depending on their results were classified as LA or HA. All participants listened to ten virtual characters telling them neutral stories. During these stories the avatars displayed nodding and smiling behaviors and the participants were observed by the use of a webcam to see whether they mimicked the virtual characters and to see how often they displayed nodding and smiling behaviors spontaneously. As predicted, LAs showed significantly more smiling spontaneously than HAs. Thought not at significant levels, LAs also showed more smile mimicking than HAs. However, there were no significant results for the nodding behavior of the participants. These results indicate a need for further research into whether people with high social anxiety display motor behaviors less and whether this affects their mimicry behavior.Show less
Mimicry of behavior is a well-known phenomenon, thought to be important for social interaction. Some studies suggest that socially anxious individuals differ from the normal population in their...Show moreMimicry of behavior is a well-known phenomenon, thought to be important for social interaction. Some studies suggest that socially anxious individuals differ from the normal population in their mimicking behavior. This difference might be a sign of a mechanism involved in social anxiety. Previous research suggests a difference between autonomic and motor mimicry. Autonomic mimicry is related to the autonomic nervous system which is largely free of conscious influence, while motor mimicry is related to the motor areas and the mirror neuron system. In this paper the focus therefore lies on autonomic pupil dilation mimicry, ruling out conscious influence on mimicry behavior. This study aims to replicate previous findings that found a difference for socially anxious peoples mimicking behavior. The direction of the difference in mimicking behavior will be addressed in the exploratory part of this study in the case of significant results. Performed was a simple regression analysis between the independent anxiety score variable obtained using the LSAS-SR and the dependent mimicry score. The results were ambiguous to a certain extent. The first analysis, including a wider range of data, was significant. It suggests an influence of social anxiety on pupil dilation mimicry, with a higher anxiety score leading to decrease in mimicry, suggesting a possible mechanism related to mimicry differences in social anxiety. However the effect size was not very high. Subsequent analysis excluding very noisy data and cases with low signal coverage led to insignificant results, suggesting normal perception and response to pupil dilation mimicry for people with social anxiety.Show less
Mimicry of subtle facial and bodily cues is an important part of social communication, as it allows for emotional contagion and affective empathy to occur. Mimicry of pupil size has been found to...Show moreMimicry of subtle facial and bodily cues is an important part of social communication, as it allows for emotional contagion and affective empathy to occur. Mimicry of pupil size has been found to occur between humans during eye-contact. In the current study we investigated whether people also mimic pupil size of bonobos (pan paniscus) and dogs (canis familiaris) as well that of humans. We predicted that humans are able to mimic pupil sizes of bonobos because bonobos are closely related to humans and because they have similar facial musculature and expressions. We also predicted that humans would show pupil mimicry towards stimuli of dogs, because these two species have co-evolved to communicate with each other and are therefore sensitive to social cues of the other species. In addition, this study aims to investigate whether humans display greater mimicry towards dogs or bonobos, and whether dog ownership or affinity with dogs enhanced pupil mimicry in the dog condition. Pupil-size data of 50 human participants was extracted while they were presented with 4-second videos of human, dog, or bonobo eyes with either constricting or dilating pupils. We conclude that pupil mimicry was found in all conditions and thus that humans can mimic pupil sizes of other humans as well as dogs and bonobos. Participants showed overall greater pupil size in the human condition compared to the bonobo condition, but no other pupil size differences were found, nor did we observe differences in pupil mimicry between the species conditions. We did not observe an effect of dog ownership or affinity with dogs on pupil mimicry in the dog condition. Human pupil mimicry of dogs and bonobos was likely facilitated by their close interspecies bond and facial similarity, respectively.Show less
