Cognitive, neural, and social mechanisms of rhythmic interpersonal coordination

Humans possess the exceptional capacity to temporally coordinate their movements with one another with a high degree of accuracy, precision, and flexibility. Musical ensemble performance is a refined example of this, where a range of cognitive and sensory-motor processes work together to support rhythmic interpersonal coordination. However, the influence of social factors on the underlying cognitive-motor and neural mechanisms that facilitate rhythmic interpersonal coordination is yet to be established. This thesis draws on theoretical perspectives related to joint action, including co-representation, self-other integration and segregation, and theoretical models of sensorimotor synchronisation to consider this topic. Three experiments were conducted to investigate how social factors influence rhythmic interpersonal coordination. This broad empirical question was broken down by considering both extrinsic factors—such as the social context and perceived characteristics of an interaction partner (e.g. the degree of partner intentionality and responsiveness)—as well as intrinsic social factors, such as individual differences in attitudes and social preferences. This thesis concludes that extrinsic and intrinsic social factors affect rhythmic interpersonal coordination at multiple levels. A key aspect of this influence relates to how people regulate the integration and segregation of their representations of self and others. However, importantly, these effects are mediated by individual differences in intrinsic social factors such as personal preferences and biases. Top-down processes related to beliefs thus influence bottom-up sensorimotor processes during joint action, but the nature of this influence appears to be different for different people. This outcome highlights the necessity of taking individual differences into account, particularly when investigating the nuances of social processing during dynamic social interactions. Furthermore, the current findings suggest that beliefs about a partner during social interaction may be just as, or even more so, influential on performance than the actual characteristics of the partner. Recognising the potency of social beliefs has implications not only for research into basic psychological mechanisms underpinning rhythmic interpersonal coordination, but also for understanding the broader social dynamics of real-life situations involving cooperative joint action understanding the broader social dynamics of real-life situations involving cooperative joint action

“Some like it hot”:spectators who score high on the personality trait openness enjoy the excitement of hearing dancers breathing without music

Music is an integral part of dance. Over the last 10 years, however, dance stimuli (without music) have been repeatedly used to study action observation processes, increasing our understanding of the influence of observer’s physical abilities on action perception. Moreover, beyond trained skills and empathy traits, very little has been investigated on how other observer or spectators’ properties modulate action observation and action preference. Since strong correlations have been shown between music and personality traits, here we aim to investigate how personality traits shape the appreciation of dance when this is presented with three different music/sounds. Therefore, we investigated the relationship between personality traits and the subjective esthetic experience of 52 spectators watching a 24 min lasting contemporary dance performance projected on a big screen containing three movement phrases performed to three different sound scores: classical music (i.e., Bach), an electronic sound-score, and a section without music but where the breathing of the performers was audible. We found that first, spectators rated the experience of watching dance without music significantly different from with music. Second, we found that the higher spectators scored on the Big Five personality factor openness, the more they liked the no-music section. Third, spectators’ physical experience with dance was not linked to their appreciation but was significantly related to high average extravert scores. For the first time, we showed that spectators’ reported entrainment to watching dance movements without music is strongly related to their personality and thus may need to be considered when using dance as a means to investigate action observation processes and esthetic preferences

How Moving Together Binds Us Together: The Social Consequences of Interpersonal Entrainment and Group Processes

Interpersonal entrainment has been shown to have a wide variety of social consequences which span far beyond those that could be considered purely pro-social. This work reviews all of the social effects of entrainment and the various explanations for them. The group formation framework emerges as a parsimonious account claiming that as we entrain our sense of self is temporarily diluted as an interdependent identity becomes more salient, thus leading to a range of social and psychological consequences which are pro-group. The sense of belonging arising from moving together is conducive towards pro-social behaviours; yet, it also makes the individual more susceptible to adopting the ideology of the group without critical thinking. We argue that the wide landscape of interpersonal entrainment’s effects reflects its primary effect, de-individuation, and the formation of a common group identity amongst co-actors

Oxytocin improves synchronisation in leader-follower interaction

The neuropeptide oxytocin has been shown to affect social interaction. Meanwhile, the underlying mechanism remains highly debated. Using an interpersonal finger-tapping paradigm, we investigated whether oxytocin affects the ability to synchronise with and adapt to the behaviour of others. Dyads received either oxytocin or a non-active placebo, intranasally. We show that in conditions where one dyad-member was tapping to another unresponsive dyad-member – i.e. one was following another who was leading/self-pacing – dyads given oxytocin were more synchronised than dyads given placebo. However, there was no effect when following a regular metronome or when both tappers were mutually adapting to each other. Furthermore, relative to their self-paced tapping partners, oxytocin followers were less variable than placebo followers. Our data suggests that oxytocin improves synchronisation to an unresponsive partner’s behaviour through a reduction in tapping-variability. Hence, oxytocin may facilitate social interaction by enhancing sensorimotor predictions supporting interpersonal synchronisation. The study thus provides novel perspectives on how neurobiological processes relate to socio-psychological behaviour and contributes to the growing evidence that synchronisation and prediction are central to social cognition

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.Roger T. Dean and Freya Bailes, and members of the Music Sound and Action Group at MARCS Institute, Eiluned Pearce and James Carney, Australian Endeavour International Postgraduate Research Scholarship, and partly by European Research Council Grant Number 295663

Synchrony and social connection in immersive Virtual Reality

Synchronising movements in time with others can have significant positive effects on affiliative attitudes and behaviors. To explore the generalizability of synchrony effects, and to eliminate confounds of suggestion, competence and shared intention typical of standard laboratory and field experiments, we used an Immersive Virtual Reality (VR) environment. Participants, represented as virtual humans, took part in a joint movement activity with two other programmed virtual humans. The timings of the co-participant characters' movements were covertly manipulated to achieve synchrony or non-synchrony with the focal participant. Participants in the synchrony condition reported significantly greater social closeness to their virtual co-participants than those in the non-synchrony condition. Results indicate that synchrony in joint action causes positive social effects and that these effects are robust in a VR setting. The research can potentially inform the development of VR interventions for social and psychological wellbeing

Verbal Synchrony and Action Dynamics in Large Groups

While synchronized movement has been shown to increase liking and feelings of togetherness between people, we investigated whether collective speaking in time would change the way that larger groups played a video game together. Anthropologists have speculated that the function of interpersonal coordination in dance, chants, and singing is not just to produce warm, affiliative feelings, but also to improve group action. The group that chants and dances together hunts well together. Direct evidence for this is sparse, as research so far has mainly studied pairs, the effects of coordinated physical movement, and measured cooperation and affiliative decisions. In our experiment, large groups of people were given response handsets to play a computer game together, in which only joint coordinative efforts lead to success. Before playing, the synchrony of their verbal behavior was manipulated. After the game, we measured group members’ affiliation toward their group, their performance on a memory task, and the way in which they played the group action task. We found that verbal synchrony in large groups produced affiliation, enhanced memory performance, and increased group members’ coordinative efforts. Our evidence suggests that the effects of synchrony are stable across modalities, can be generalized to larger groups and have consequences for action coordination

Beyond simultaneity: temporal interdependence of behaviour is key to affiliative effects of interpersonal synchrony in children

Interpersonal synchrony (IS) is the temporal co-ordination of behavior during social interactions. IS acts as a social cue signifying affiliation, both when children witness IS between others and when they experience it themselves. However, it is unclear which temporal qualities of IS produce these effects, and why. We hypothesized that the simultaneity and temporal regularity of partners’ actions would each influence affiliation judgements, and that subjective perceptions of IS (‘togetherness’) would play a role in mediating these relations. In two online studies, children aged 4-11 years listened to a pair of children tapping together (witnessed IS; N=68) or themselves tapped with another child (experienced IS; N=63). Tapping partners were presented as real but were virtual. The simultaneity and regularity of their tapping was systematically manipulated across trials. For witnessed IS, both the simultaneity and regularity of partners’ tapping significantly positively affected the perceived degree of affiliation between them. These effects were mediated by the perceived togetherness of the tapping. No affiliative effects of IS were found in the experienced IS condition. Our findings suggest that both the simultaneity and regularity of partners’ actions influence children’s affiliation judgements when witnessing IS, via elicited perceptions of togetherness. We conclude that temporal interdependence – which includes but is not limited to simultaneity of action – is responsible for inducing perceptions of affiliation during witnessed IS