Heterogeneity of long-history migration predicts smiling, laughter and positive emotion across the globe and within the United States

Development of a novel tool to investigate human laughter behaviour and experience

We present a questionnaire exploring everyday laughter experience. We developed a 30-item questionnaire in English and collected data on an English-speaking sample (N = 823). Based on Principal Component Analysis (PCA), we identified four dimensions which accounted for variations in people's experiences of laughter: laughter frequency ('Frequency'), social usage of laughter ('Usage'), understanding of other people's laughter ('Understanding'), and feelings towards laughter ('Liking'). Reliability and validity of the LPPQ were assessed. To explore potential similarities and differences based on culture and language, we collected data with Mandarin Chinese-speaking population (N = 574). A PCA suggested the extraction of the same four dimensions, with some item differences between English and Chinese versions. The Laughter Production and Perception Questionnaire (LPPQ) will advance research into the experience of human laughter, which has a potentially crucial role in everyday life.

Face coverings differentially alter valence judgments of emotional expressions

Face masks that prevent disease transmission obscure facial expressions, impairing nonverbal communication. We assessed the impact of lower (masks) and upper (sunglasses) face coverings on emotional valence judgments of clearly valenced (fearful, happy) and ambiguously valenced (surprised) expressions, the latter of which have both positive and negative meaning. Masks, but not sunglasses, impaired judgments of clearly valenced expressions compared to faces without coverings. Drift diffusion models revealed that lower, but not upper, face coverings slowed evidence accumulation and affected differences in non-judgment processes (i.e., stimulus encoding, response execution time) for all expressions. Our results confirm mask-interference effects in nonverbal communication. The findings have implications for nonverbal and intergroup communication, and we propose guidance for implementing strategies to overcome mask-related interference.

Ancestral Diversity: A Socioecological Account of Emotion Culture

Cultural differences in emotion expression, experience, and regulation can cause misunderstandings with lasting effects on interpersonal, intergroup, and international relations. A full account of the factors responsible for the emergence of different cultures of emotion is therefore urgent. Here we propose that the ancestral diversity of regions of the world, determined by colonization and sometimes forced migration of humans over centuries, explains significant variation in cultures of emotion. We review findings that relate the ancestral diversity of the world's countries to present-day differences in display rules for emotional expression, the clarity of expressions, and the use of specific facial expressions such as the smile. Results replicate at the level of the states of the United States, which also vary in ancestral diversity. Further, we suggest that historically diverse contexts provide opportunities for individuals to exercise physiological processes that support emotion regulation, resulting in average regional differences in cardiac vagal tone. We conclude that conditions created by the long-term commingling of the world's people have predictable effects on the evolution of emotion cultures and provide a roadmap for future research to analyze causation and isolate mechanisms linking ancestral diversity to emotion.

Living in ancestrally diverse states of the United States is associated with greater vagal tone

Historically, exposure to dissimilar others ("strangers") was a physiologically arousing event-resulting in avoidance, distrust, and even conflict. Despite this, contemporary migration patterns are increasing intergroup contact. What gives rise to an individual's ability to regulate their arousal such that social engagement with outgroup members is possible? We propose that cultural practices that evolve in ancestrally diverse, compared to ancestrally homogeneous, societies provide more opportunities for society members to engage in emotion regulation. This regulatory exercise, in turn, promotes higher vagal tone-a physiological indicator of one's ability to effectively manage arousal in social interaction. In a secondary analysis of data from the MIDUS 2 Biomarker Project, we find that the ancestral diversity of the states of the United States significantly predicts the average vagal tone of the state's citizens. The findings suggest that social context is associated with predictable and significant adaptations of human physiology over individual lifetimes.

Robert Provine: the critical human importance of laughter, connections and contagion

Robert Provine made several critically important contributions to science, and in this paper, we will elaborate some of his research into laughter and behavioural contagion. To do this, we will employ Provine's observational methods and use a recorded example of naturalistic laughter to frame our discussion of Provine's work. The laughter is from a cricket commentary broadcast by the British Broadcasting Corporation in 1991, in which Jonathan Agnew and Brian Johnston attempted to summarize that day's play, at one point becoming overwhelmed by laughter. We will use this laughter to demonstrate some of Provine's key points about laughter and contagious behaviour, and we will finish with some observations about the importance and implications of the differences between humans and other mammals in their use of contagious laughter.

This article is part of the theme issue ‘Cracking the laugh code: laughter through the lens of biology, psychology and neuroscience’.

A Taxonomy of Social Errors in Human-Robot Interaction

Robotic applications have entered various aspects of our lives, such as health care and educational services. In such Human-robot Interaction (HRI), trust and mutual adaption are established and maintained through a positive social relationship between a user and a robot. This social relationship relies on the perceived competence of a robot on the social-emotional dimension. However, because of technical limitations and user heterogeneity, current HRI is far from error-free, especially when a system leaves controlled lab environments and is applied to in-the-wild conditions. Errors in HRI may either degrade a user’s perception of a robot’s capability in achieving a task (defined as performance errors in this work) or degrade a user’s perception of a robot’s socio-affective competence (defined as social errors in this work). The impact of these errors and effective strategies to handle such an impact remains an open question. We focus on social errors in HRI in this work. In particular, we identify the major attributes of perceived socio-affective competence by reviewing human social interaction studies and HRI error studies. This motivates us to propose a taxonomy of social errors in HRI. We then discuss the impact of social errors situated in three representative HRI scenarios. This article provides foundations for a systematic analysis of the social-emotional dimension of HRI. The proposed taxonomy of social errors encourages the development of user-centered HRI systems, designed to offer positive and adaptive interaction experiences and improved interaction outcomes.

Changing cultures, changing brains: A framework for integrating cultural neuroscience and cultural change research

Cultural neuroscience research has provided substantial evidence that culture shapes the brain by providing systematically different sets of experiences. However, cultures are ever-changing in response to the physical and social environment. In the present paper, we integrate theories and methods from cultural neuroscience with the emerging body of research on cultural change and suggest several ways in which the two fields can inform each other. First, we propose that the cultural change perspective helps us reexamine what is meant by culturally typical experiences, which are shaped by the dynamic interaction between cultural norms, values, meanings, and other environmental constraints on behavior. It also allows us to make predictions about the variability/stability of cultural neural differences over time. Then, we discuss how methods used in cultural change research may be applied to cultural neuroscience research and vice versa. We end with a "blue sky vision" for a neuroscience of cultural change.

Human perception and biosignal-based identification of posed and spontaneous smiles

Facial expressions are behavioural cues that represent an affective state. Because of this, they are an unobtrusive alternative to affective self-report. The perceptual identification of facial expressions can be performed automatically with technological assistance. Once the facial expressions have been identified, the interpretation is usually left to a field expert. However, facial expressions do not always represent the felt affect; they can also be a communication tool. Therefore, facial expression measurements are prone to the same biases as self-report. Hence, the automatic measurement of human affect should also make inferences on the nature of the facial expressions instead of describing facial movements only. We present two experiments designed to assess whether such automated inferential judgment could be advantageous. In particular, we investigated the differences between posed and spontaneous smiles. The aim of the first experiment was to elicit both types of expressions. In contrast to other studies, the temporal dynamics of the elicited posed expression were not constrained by the eliciting instruction. Electromyography (EMG) was used to automatically discriminate between them. Spontaneous smiles were found to differ from posed smiles in magnitude, onset time, and onset and offset speed independently of the producer's ethnicity. Agreement between the expression type and EMG-based automatic detection reached 94% accuracy. Finally, measurements of the agreement between human video coders showed that although agreement on perceptual labels is fairly good, the agreement worsens with inferential labels. A second experiment confirmed that a layperson's accuracy as regards distinguishing posed from spontaneous smiles is poor. Therefore, the automatic identification of inferential labels would be beneficial in terms of affective assessments and further research on this topic.

Population Diversity and Ancestral Diversity As Distinct Contributors to Outgroup Prejudice

Previous research has shown conflicting findings on how population diversity influences outgroup prejudice. In some cases, prejudice is greater when minority groups make up a larger portion of the population, whereas in other cases, prejudice is lower as diversity increases. This article examined how the diversity of a culture's ancestry-or its historical heterogeneity-would be related to outgroup attitudes. Historically heterogeneous populations descend from ancestors who have migrated from many parts of the world over the past 500 years and, as a result, have a longer legacy of contact with diverse groups of people. The results of two cross-cultural studies found that greater heterogeneity predicted lower levels of outgroup prejudice, and some evidence that diversity in the current population was related to increased prejudice. The findings suggest that intergroup attitudes have deeply entrenched roots that cannot be fully understood by looking at current indicators.

Residential Mobility Fosters Sensitivity to the Disappearance of Happiness

We conducted two studies to examine the hypothesis that residential mobility would evoke anxiety and foster sensitivity to signs of disapproval, such as the disappearance of happiness. American and Japanese participants were asked to watch happy-to-neutral movies and sad-to-neutral movies and judge the point at which they thought that their initial expressions had disappeared. We found that, regardless of cultures, participants who had experienced frequent moving (Study 1) and those asked to imagine and describe a mobile lifestyle of frequent moving (Study 2) judged the disappearance of happy faces faster than those who did not experience or imagine frequent moving. Our results were also in line with the previous finding in which Japanese were more vigilant than Americans in regards to the disappearance of happy faces. Moreover, we found that imagining a mobile lifestyle made participants feel more concerned than when imagining a stable lifestyle. The implications for the social skills needed for people in the globalising world are discussed.