Silent disco: dancing in synchrony leads to elevated pain thresholds and social closeness.

Moving in synchrony leads to cooperative behaviour and feelings of social closeness, and dance (involving synchronisation to others and music) may cause social bonding, possibly as a consequence of released endorphins. This study uses an experimental paradigm to determine which aspects of synchrony in dance are associated with changes in pain threshold (a proxy for endorphin release) and social bonding between strangers. Those who danced in synchrony experienced elevated pain thresholds, whereas those in the partial and asynchrony conditions experienced no analgesic effects. Similarly, those in the synchrony condition reported being more socially bonded, although they did not perform more cooperatively in an economic game. This experiment suggests that dance encourages social bonding amongst co-actors by stimulating the production of endorphins, but may not make people more altruistic. We conclude that dance may have been an important human behaviour evolved to encourage social closeness between strangers.

Group music performance causes elevated pain thresholds and social bonding in small and large groups of singers.

Over our evolutionary history, humans have faced the problem of how to create and maintain social bonds in progressively larger groups compared to those of our primate ancestors. Evidence from historical and anthropological records suggests that group music-making might act as a mechanism by which this large-scale social bonding could occur. While previous research has shown effects of music making on social bonds in small group contexts, the question of whether this effect 'scales up' to larger groups is particularly important when considering the potential role of music for large-scale social bonding. The current study recruited individuals from a community choir that met in both small (n = 20 - 80) and large (a 'megachoir' combining individuals from the smaller subchoirs n = 232) group contexts. Participants gave self-report measures (via a survey) of social bonding and had pain threshold measurements taken (as a proxy for endorphin release) before and after 90 minutes of singing. Results showed that feelings of inclusion, connectivity, positive affect, and measures of endorphin release all increased across singing rehearsals and that the influence of group singing was comparable for pain thresholds in the large versus small group context. Levels of social closeness were found to be greater at pre- and post-levels for the small choir condition. However, the large choir condition experienced a greater change in social closeness as compared to the small condition. The finding that singing together fosters social closeness - even in large contexts where individuals are not known to each other - is consistent with evolutionary accounts that emphasize the role of music in social bonding, particularly in the context of creating larger cohesive groups than other primates are able to manage.

Does implied community size predict likeability of a similar stranger?

Homophily, the tendency for people to cluster with similar others, has primarily been studied in terms of proximal, psychological causes, such as a tendency to have positive associations with people who share traits with us. Here we investigate whether homophily could be correlated with perceived group membership, given that sharing traits with other people might signify membership of a specific community. In order to investigate this, we tested whether the amount of homophily that occurs between strangers is dependent on the number of people they believe share the common trait (i.e. the size of group that the trait identifies). In two experiments, we show that more exclusive (smaller) groups evoke more positive ratings of the likeability of a stranger. When groups appear to be too inclusive (i.e. large) homophily no longer occurs, suggesting that it is not only positive associations with a trait that cause homophily, but a sense of the exclusiveness of a group is also important. These results suggest that group membership based on a variety of traits can encourage cohesion between people from diverse backgrounds, and may be a useful tool in overcoming differences between groups.

Synchrony and exertion during dance independently raise pain threshold and encourage social bonding.

Group dancing is a ubiquitous human activity that involves exertive synchronized movement to music. It is hypothesized to play a role in social bonding, potentially via the release of endorphins, which are analgesic and reward-inducing, and have been implicated in primate social bonding. We used a 2 × 2 experimental design to examine effects of exertion and synchrony on bonding. Both demonstrated significant independent positive effects on pain threshold (a proxy for endorphin activation) and in-group bonding. This suggests that dance which involves both exertive and synchronized movement may be an effective group bonding activity.

Evidence for multiple strategies in off-beat tapping with anisochronous stimuli.

There is a large body of evidence relating to the ways that people tap in time with sounds, and perform error correction in order to do this. However, off-beat tapping is less well investigated than on-beat tapping. The current study involves coordinating with a stimulus sequence with underlying isochrony and systematic deviations from this isochrony that increase or decrease in magnitude to look at people's capacity to error-correct when performing off-beat synchronisation with a set of sounds. Participants were instructed to 'tap between the tones' but 'try to maintain regularity'. While analysis using typical methods suggested a form of error correction was occurring, a series of more complex analyses demonstrated that participants' performance during each trial can be classified according to one of four different strategies: maintaining a regular pulse, error correction, phase resetting, and negative error correction. While maintaining a regular pulse was the preferred strategy in conditions with increasingly isochronous stimuli, the majority of trials are best explained by other strategies, suggesting that participants were generally influenced by variability in the stimuli.

Synchronising movements with the sounds of a virtual partner enhances partner likeability.

Previous studies have demonstrated that synchronising movements with other people can influence affiliative behaviour towards them. While research has focused on synchronisation with visually observed movement, synchronisation with a partner who is heard may have similar effects. We replicate findings showing that synchronisation can influence ratings of likeability of a partner, but demonstrate that this is possible with virtual interaction, involving a video of a partner. Participants performed instructed synchrony in time to sounds instead of the observable actions of another person. Results show significantly higher ratings of likeability of a partner after moving at the same time as sounds attributed to that partner, compared with moving in between sounds. Objectively quantified synchrony also correlated with ratings of likeability. Belief that sounds were made by another person was manipulated in Experiment 2, and results demonstrate that when sounds are attributed to a computer, ratings of likeability are not affected by moving in or out of time. These findings demonstrate that interaction with sound can be experienced as social interaction in the absence of genuine interpersonal contact, which may help explain why people enjoy engaging with recorded music.

Signals through music and dance: Perceived social bonds and formidability on collective movement.

Previous studies have suggested that the prosocial effects which arise following synchrony during music and dance may serve as a mechanism for people to bond socially. However, other research has proposed that synchrony could be a mechanism for signalling coalition to demonstrate fitness, which is expressed by a group's ability to effectively cooperate. In the present studies, we compared these theories by showing participants realistic virtual avatars engaged in different forms of group dance and then examining their perceived social closeness and formidability of the dance groups. We conducted two studies to assess the perceptual influence of movement type (unison vs. coordinated) and movement quality (temporally aligned vs. temporally misaligned). We predicted that the difference in the ratings of closeness and formidability would only emerge when the groups align movements, and this was supported. We also hypothesised that unison movement would better signal formidability while coordinated movement would better signal a group's social closeness. However, unison movement yielded higher ratings than coordinated movement for both formidability and social closeness, suggesting that a group should move in complete synchrony to maximally indicate their fitness and social bonds.

Functional Benefits of (Modest) Alcohol Consumption.

Alcohol use has a long and ubiquitous history. Despite considerable research on the misuse of alcohol, no one has ever asked why it might have become universally adopted, although the conventional view assumes that its only benefit is hedonic. In contrast, we suggest that alcohol consumption was adopted because it has social benefits that relate both to health and social bonding. We combine data from a national survey with data from more detailed behavioural and observational studies to show that social drinkers have more friends on whom they can depend for emotional and other support, and feel more engaged with, and trusting of, their local community. Alcohol is known to trigger the endorphin system, and the social consumption of alcohol may thus have the same effect as the many other social activities such as laughter, singing and dancing that we use as a means of servicing and reinforcing social bonds.

Rapid learning of associations between sound and action through observed movement. A TMS study.

Research has established that there is a cognitive link between perception and production of the same movement. However, there has been relatively little research into the relevance of this for non-expert perceivers, such as music listeners who do not play instruments themselves. In two experiments we tested whether participants can quickly learn new associations between sounds and observed movement without performing those movements themselves. We measured motor evoked potentials (MEPs) in the first dorsal interosseous muscle of participants' right hands while test tones were heard and single transcranial magnetic stimulation (TMS) pulses were used to trigger motor activity. In Experiment 1 participants in a 'human' condition (n=4) learnt to associate the test tone with finger movement of the experimenter, while participants in a 'computer' condition (n=4) learnt that the test tone was triggered by a computer. Participants in the human condition showed a larger increase in MEPs compared with those in the computer condition. In a second experiment pairing between sounds and movement occurred without participants repeatedly observing the movement and we found no such difference between the human (n=4) and computer (n=4) conditions. These results suggest that observers can quickly learn to associate sound with movement, so it should not be necessary to have played an instrument to experience some motor resonance when hearing that instrument.

Joint attention, shared goals, and social bonding.

There has recently been interest in the ways in which coordinated movements encourage coactors to feel socially closer to one another, but this has generally overlooked the importance of necessary precursors to this joint action. Here we target two low-level behaviours involved in social coordination that may mediate a relationship between joint actions and social bonding, namely joint attention and shared goals. Participants engaged in a simple reaction time task while sitting next to a partner performing the same task. In a joint attention condition, both participants attended to stimuli presented on the same half of a computer screen, while in a control condition, they attended to opposite sides of the computer screen. Shared goals were manipulated by giving participants the instruction to keep below a threshold score for both individual response times and accuracy (individual goal), or their joint mean response time and accuracy (i.e., averaging their mean response time and accuracy with that of their partner: shared goal). Attending to the same side of the screen led to higher ratings on a composite social bonding index directed towards a partner, while shared goals did not cause any effects on partner ratings. Joint attention was sufficient to encourage social closeness with an interaction partner, which suggests that any activities which encourage attending to the same point in space could have some influence on how connected coactors feel about one another.

The Complexity of Jokes Is Limited by Cognitive Constraints on Mentalizing.

Although laughter is probably of deep evolutionary origin, the telling of jokes, being language-based, is likely to be of more recent origin within the human lineage. In language-based communication, speaker and listener are engaged in a process of mutually understanding each other's intentions (mindstates), with a conversation minimally requiring three orders of intentionality. Mentalizing is cognitively more demanding than non-mentalizing cognition, and there is a well-attested limit at five orders in the levels of intentionality at which normal adult humans can work. Verbal jokes commonly involve commentary on the mindstates of third parties, and each such mindstate adds an additional level of intentionality and its corresponding cognitive load. We determined the number of mentalizing levels in a sample of jokes told by well-known professional comedians and show that most jokes involve either three or five orders of intentionality on the part of the comedian, depending on whether or not the joke involves other individuals' mindstates. Within this limit there is a positive correlation between increasing levels of intentionality and subjective ratings of how funny the jokes are. The quality of jokes appears to peak when they include five or six levels of intentionality, which suggests that audiences appreciate higher mentalizing complexity whilst working within their natural cognitive constraints.

Is group singing special? Health, well-being and social bonds in community-based adult education classes.

Evidence demonstrates that group singing improves health and well-being, but the precise mechanisms remain unknown. Given that cohesive social networks also positively influence health, we focus on the social aspects of singing, exploring whether improvements in health and well-being are mediated by stronger social bonds, both to the group as a whole (collective-bonding) and to individual classmates (relational-bonding). To do so, seven newly-formed community-based adult education classes (four singing, N=84, and three comparison classes studying creative writing or crafts, N=51) were followed over seven months. Self-report questionnaire data on mental and physical health, well-being, and social bonding were collected at Months 1, 3 and 7. We demonstrate that physical and mental health and satisfaction with life significantly improved over time in both conditions. Path analysis did not show any indirect effects via social bonding of Condition on health and well-being. However, higher collective-bonding at timepoint 3 significantly predicted increased flourishing, reduced anxiety and improved physical health independently of baseline levels. In contrast, relational-bonding showed no such effects, suggesting that it is feeling part of a group that particularly yields health and well-being benefits. Moreover, these results indicate that singing may not improve health and well-being more than other types of activities. Nonetheless, these findings encourage further work to refine our understanding of the social aspects of community-based adult education classes in promoting health, well-being and community cohesion.

Singing together or apart: The effect of competitive and cooperative singing on social bonding within and between sub-groups of a university Fraternity.

Singing together seems to facilitate social bonding, but it is unclear whether this is true in all contexts. Here we examine the social bonding outcomes of naturalistic singing behaviour in a European university Fraternity composed of exclusive 'Cliques': recognised sub-groups of 5-20 friends who adopt a special name and identity. Singing occurs frequently in this Fraternity, both 'competitively' (contests between Cliques) and 'cooperatively' (multiple Cliques singing together). Both situations were re-created experimentally in order to explore how competitive and cooperative singing affects feelings of closeness towards others. Participants were assigned to teams of four and were asked to sing together with another team either from the same Clique or from a different Clique. Participants (N = 88) felt significantly closer to teams from different Cliques after singing with them compared to before, regardless of whether they cooperated with (singing loudly together) or competed against (trying to singing louder than) the other team. In contrast, participants reported reduced closeness with other teams from their own Clique after competing with them. These results indicate that group singing can increase closeness to less familiar individuals regardless of whether they share a common motivation, but that singing competitively may reduce closeness within a very tight-knit group.

Musical Sounds, Motor Resonance, and Detectable Agency.

This paper discusses the paradox that while human music making evolved and spread in an environment where it could only occur in groups, it is now often apparently an enjoyable asocial phenomenon. Here I argue that music is, by definition, sound that we believe has been in some way organized by a human agent, meaning that listening to any musical sounds can be a social experience. There are a number of distinct mechanisms by which we might associate musical sound with agency. While some of these mechanisms involve learning motor associations with that sound, it is also possible to have a more direct relationship from musical sound to agency, and the relative importance of these potentially independent mechanisms should be further explored. Overall, I conclude that the apparent paradox of solipsistic musical engagement is in fact unproblematic, because the way that we perceive and experience musical sounds is inherently social.

Playing with Strangers: Which Shared Traits Attract Us Most to New People?

Homophily, the tendency for individuals to associate with those who are most similar to them, has been well documented. However, the influence of different kinds of similarity (e.g. relating to age, music taste, ethical views) in initial preferences for a stranger have not been compared. In the current study, we test for a relationship between sharing a variety of traits (i.e. having different kinds of similarity) with a stranger and the perceived likeability of that stranger. In two online experiments, participants were introduced to a series of virtual partners with whom they shared traits, and subsequently carried out activities designed to measure positivity directed towards those partners. Greater numbers of shared traits led to linearly increasing ratings of partner likeability and ratings on the Inclusion of Other in Self scale. We identified several consistent predictors of these two measures: shared taste in music, religion and ethical views. These kinds of trait are likely to be judged as correlates of personality or social group, and may therefore be used as proxies of more in-depth information about a person who might be socially more relevant.

The ice-breaker effect: singing mediates fast social bonding.

It has been proposed that singing evolved to facilitate social cohesion. However, it remains unclear whether bonding arises out of properties intrinsic to singing or whether any social engagement can have a similar effect. Furthermore, previous research has used one-off singing sessions without exploring the emergence of social bonding over time. In this semi-naturalistic study, we followed newly formed singing and non-singing (crafts or creative writing) adult education classes over seven months. Participants rated their closeness to their group and their affect, and were given a proxy measure of endorphin release, before and after their class, at three timepoints (months 1, 3 and 7). We show that although singers and non-singers felt equally connected by timepoint 3, singers experienced much faster bonding: singers demonstrated a significantly greater increase in closeness at timepoint 1, but the more gradual increase shown by non-singers caught up over time. This represents the first evidence for an 'ice-breaker effect' of singing in promoting fast cohesion between unfamiliar individuals, which bypasses the need for personal knowledge of group members gained through prolonged interaction. We argue that singing may have evolved to quickly bond large human groups of relative strangers, potentially through encouraging willingness to coordinate by enhancing positive affect.

Dysrhythmia: a specific congenital rhythm perception deficit.

Why do some people have problems "feeling the beat"? Here we investigate participants with congenital impairments in musical rhythm perception and production. A web-based version of the Montreal Battery of Evaluation of Amusia was used to screen for difficulties with rhythmic processing in a large sample and we identified three "dysrhythmic" individuals who scored below cut-off for the rhythm subtest, but not the pitch-based subtests. Follow-up testing in the laboratory was conducted to characterize the nature of both rhythm perception and production deficits in these dysrhythmic individuals. We found that they differed from control participants when required to synchronize their tapping to an external stimulus with a metrical pulse, but not when required to tap spontaneously (with no external stimulus) or to tap in time to an isochronous stimulus. Dysrhythmics exhibited a general tendency to tap at half the expected tempo when asked to synchronize to the beat of strongly metrical rhythms. These results suggest that the individuals studied here did not have motor production problems, but suffer from a selective rhythm perception deficit that influences the ability to entrain to metrical rhythms.

Music and social bonding: "self-other" merging and neurohormonal mechanisms.

It has been suggested that a key function of music during its development and spread amongst human populations was its capacity to create and strengthen social bonds amongst interacting group members. However, the mechanisms by which this occurs have not been fully discussed. In this paper we review evidence supporting two thus far independently investigated mechanisms for this social bonding effect: self-other merging as a consequence of inter-personal synchrony, and the release of endorphins during exertive rhythmic activities including musical interaction. In general, self-other merging has been experimentally investigated using dyads, which provide limited insight into large-scale musical activities. Given that music can provide an external rhythmic framework that facilitates synchrony, explanations of social bonding during group musical activities should include reference to endorphins, which are released during synchronized exertive movements. Endorphins (and the endogenous opioid system (EOS) in general) are involved in social bonding across primate species, and are associated with a number of human social behaviors (e.g., laughter, synchronized sports), as well as musical activities (e.g., singing and dancing). Furthermore, passively listening to music engages the EOS, so here we suggest that both self-other merging and the EOS are important in the social bonding effects of music. In order to investigate possible interactions between these two mechanisms, future experiments should recreate ecologically valid examples of musical activities.

Synchronization can influence trust following virtual interaction.

Synchronization has recently received attention as a form of interpersonal interaction that may affect the affiliative relationships of those engaged in it. While there is evidence to suggest that synchronized movements lead to increased affiliative behavior (Hove & Risen, 2009; Valdesolo & DeSteno, 2011; Wiltermuth & Heath, 2009), the influence of other interpersonal cues has yet to be fully controlled. The current study controls for these features by using computer algorithms to replace human partners. By removing genuine interpersonal interaction, it also tests whether sounds alone can influence affiliative relationships, when it appears that another human agent has triggered those sounds. Results suggest that subjective experience of synchrony had a positive effect on a measure of trust, but task success was a similarly good predictor. An objective measure of synchrony was only related to trust in conditions where participants were instructed to move at the same time as stimuli.