Synchronized movement experience enhances peer cooperation in preschool children

Comparison of speech and music input in North American infants' home environment over the first 2 years of life

Infants are immersed in a world of sounds from the moment their auditory system becomes functional, and experience with the auditory world shapes how their brain processes sounds in their environment. Across cultures, speech and music are two dominant auditory signals in infants' daily lives. Decades of research have repeatedly shown that both quantity and quality of speech input play critical roles in infant language development. Less is known about the music input infants receive in their environment. This study is the first to compare music input to speech input across infancy by analyzing a longitudinal dataset of daylong audio recordings collected in English-learning infants' home environments, at 6, 10, 14, 18, and 24 months of age. Using a crowdsourcing approach, 643 naïve listeners annotated 12,000 short snippets (10 s) randomly sampled from the recordings using Zooniverse, an online citizen-science platform. Results show that infants overall receive significantly more speech input than music input and the gap widens as the infants get older. At every age point, infants were exposed to more music from an electronic device than an in-person source; this pattern was reversed for speech. The percentage of input intended for infants remained the same over time for music while that percentage significantly increased for speech. We propose possible explanations for the limited music input compared to speech input observed in the present (North American) dataset and discuss future directions. We also discuss the opportunities and caveats in using a crowdsourcing approach to analyze large audio datasets. A video abstract of this article can be viewed at https://youtu.be/lFj_sEaBMN4.

Interpersonal motor synchrony in autism: a systematic review and meta-analysis

Introduction

Interpersonal motor synchrony (IMS) is the spontaneous, voluntary, or instructed coordination of movements between interacting partners. Throughout the life cycle, it shapes social exchanges and interplays with intra- and inter-individual characteristics that may diverge in Autism Spectrum Disorder (ASD). Here we perform a systematic review and meta-analysis to summarize the extant literature and quantify the evidence about reduced IMS in dyads including at least one participant with a diagnosis of ASD.

Methods

Empirical evidence from sixteen experimental studies was systematically reviewed, encompassing spontaneous and instructed paradigms as well as a paucity of measures used to assess IMS. Of these, thirteen studies (n = 512 dyads) contributed measures of IMS with an in situ neurotypical partner (TD) for ASD and control groups, which could be used for meta-analyses.

Results

Reduced synchronization in ASD-TD dyads emerged from both the systematic review and meta-analyses, although both small and large effect sizes (i.e., Hedge's g) in favor of the control group are consistent with the data (Hedge's g = .85, p < 0.001, 95% CI[.35, 1.35], 95% PI[-.89, 2.60]).

Discussion

Uncertainty is discussed relative to the type of task, measures, and age range considered in each study. We further discuss that sharing similar experiences of the world might help to synchronize with one another. Future studies should not only assess whether reduced IMS is consistently observed in ASD-TD dyads and how this shapes social exchanges, but also explore whether and how ASD-ASD dyads synchronize during interpersonal exchanges.

Social interaction links active musical rhythm engagement and expressive communication in autistic toddlers

Rhythm is implicated in both social and linguistic development. Rhythm perception and production skills are also key vulnerabilities in neurodevelopmental disorders such as autism which impact social communication. However, direct links between musical rhythm engagement and expressive communication in autism is not clearly evident. This absence of a direct connection between rhythm and expressive communication indicates that the mechanism of action between rhythm and expressive communication may recruit other cognitive or developmental factors. We hypothesized that social interactions, including general interpersonal relationships and interactive music-making involving children and caregivers, were a significant such factor, particularly in autism. To test this, we collected data from parents of autistic and nonautistic children 14-36 months of age, including parent reports of their children's rhythmic musical engagement, general social skills, parent-child musical interactions, and expressive communication skills. Path analysis revealed a system of independent, indirect pathways from rhythmic musical engagement to expressive communication via social skills and parent-child musical interactions in autistic toddlers. Such a system implies both that social and musical interactions represent crucial links between rhythm and language and that different kinds of social interactions play parallel, independent roles linking rhythmic musical engagement with expressive communication skills.

Spontaneous bodily coordination varies across affective and intellectual child-adult interactions

Research on child-adult interactions has identified that the morphology of bodily coordination seems to be sensitive to age and type of interaction. Mirror-like imitation emerges earlier in life and is more common during emotionally laden interactions, while anatomical imitation is acquired later and associated with cognitive tasks. However, it remains unclear whether these morphologies also vary with age and type of interaction during spontaneous coordination. Here we report a motion capture study comparing the spontaneous coordination patterns of thirty-five 3-year-old (20 girls; Mage = 3.15 years) and forty 6-year-old children (20 girls; Mage = 6.13 years) interacting with unacquainted adults during two storytelling sessions. The stories narrated the search of a character for her mother (Predominantly Affective Condition) or an object (Predominantly Intellectual Condition) inside a supermarket. Results show that children of both ages consistently coordinated their spontaneous movements towards adult storytellers, both in symmetric and asymmetric ways. However, symmetric coordination was more prominent in 3-year-old children and during predominantly emotional interactions, whereas asymmetric coordination prevailed in 6-year-old children and during predominantly intellectual interactions. These results add evidence from spontaneous interactions in favor of the hypothesis that symmetric coordination is associated with affective interactions and asymmetric coordination with intellectual ones.

Syncopation as Probabilistic Expectation: Conceptual, Computational, and Experimental Evidence

Definitions of syncopation share two characteristics: the presence of a meter or analogous hierarchical rhythmic structure and a displacement or contradiction of that structure. These attributes are translated in terms of a Bayesian theory of syncopation, where the syncopation of a rhythm is inferred based on a hierarchical structure that is, in turn, learned from the ongoing musical stimulus. Several experiments tested its simplest possible implementation, with equally weighted priors associated with different meters and independence of auditory events, which can be decomposed into two terms representing note density and deviation from a metric hierarchy. A computational simulation demonstrated that extant measures of syncopation fall into two distinct factors analogous to the terms in the simple Bayesian model. Next, a series of behavioral experiments found that perceived syncopation is significantly related to both terms, offering support for the general Bayesian construction of syncopation. However, we also found that the prior expectations associated with different metric structures are not equal across meters and that there is an interaction between density and hierarchical deviation, implying that auditory events are not independent from each other. Together, these findings provide evidence that syncopation is a manifestation of a form of temporal expectation that can be directly represented in Bayesian terms and offer a complementary, feature-driven approach to recent Bayesian models of temporal prediction.

Music in the Middle: A Culture-Cognition-Mediator Model of Musical Functionality

Music is both universal, appearing in every known human culture, and culture-specific, often defying intelligibility across cultural boundaries. This duality has been the source of debate within the broad community of music researchers, and there have been significant disagreements both on the ontology of music as an object of study and the appropriate epistemology for that study. To help resolve this tension, I present a culture-cognition-mediator model that situates music as a mediator in the mutually constitutive cycle of cultures and selves representing the ways individuals both shape and are shaped by their cultural environments. This model draws on concepts of musical grammars and schema, contemporary theories in developmental and cultural psychology that blur the distinction between nature and nurture, and recent advances in cognitive neuroscience. Existing evidence of both directions of causality is presented, providing empirical support for the conceptual model. The epistemological consequences of this model are discussed, specifically with respect to transdisciplinarity, hybrid research methods, and several potential empirical applications and testable predictions as well as its import for broader ontological conversations around the evolutionary origins of music itself.

Musical coordination affects children's perspective-taking, but musical synchrony does not

Perspective-taking, which is important for communication and social activities, can be cultivated through joint actions, including musical activities in children. We examined how rhythmic activities requiring coordination affect perspective-taking in a referential communication task with 100 Chinese 4- to 6-year-old children. In Study 1, 5- to 6-year-old children played an instrument with a virtual partner in one of three coordination conditions: synchrony, asynchrony, and antiphase synchrony. Eye movements were then monitored with the partner giving instructions to identify a shape referent which included a pre-nominal scalar adjective (e.g., big cubic block). When the target contrast (a small cubic block) was in the shared ground and a competitor contrast was occluded for the partner, participants who used perspective differences could, in principle, identify the intended referent before the shape was named. We hypothesized that asynchronous and antiphase synchronous musical activities, which require self-other distinction, might have stronger effects on perspective-taking than synchronous activity. Children in the asynchrony and antiphase synchrony conditions, but not the synchrony condition, showed anticipatory looks at the target, demonstrating real-time use of the partner's perspective. Study 2 was conducted to determine if asynchrony and antiphase asynchrony resulted in perspective-taking that otherwise would not have been observed, or if synchronous coordination inhibited perspective-taking that would otherwise have occurred. We found no evidence for online perspective-taking in 4- to 6-year-old children without music manipulation. Therefore, playing instruments asynchronously or in alternation, but not synchronously, increases perspective-taking in children of this age, likely by training self-other distinction and control. A video abstract of this article can be viewed at https://youtu.be/TM9h_GpFlsA. RESEARCH HIGHLIGHTS: This study is the first to show that rhythmic coordination, a form of non-linguistic interaction, can affect children's performance in a subsequent linguistic task. Eye-movement data revealed that children's perspective-taking in language processing was facilitated by prior asynchronous and antiphase synchronous musical interactions, but not by synchronous coordination. The results challenge the common "similar is better" view, suggesting that maintaining self-other distinction may benefit social interactions that involve representing individual differences.

When I move, you move: Associations between automatic and person-coded measures of infant-mother synchrony during free-play using virtual in-home data collection

The relationship between movement synchrony and global scores of behavioral synchrony were investigated during a naturalistic free-play between 33 infants (ages 12- to 24-months) and their mothers using a video-conferencing platform. We assessed movement synchrony by applying an automatic tool, motion-energy analysis (MEA), to the obtained video data. Dyadic movement synchrony was associated with higher levels of maternal sensitivity, infant involvement, dyadic reciprocity, and a child-led interaction pattern. This demonstrates the feasibility of using MEA as an automatic tool for assessing movement synchrony in mother-infant dyads and its application for investigating naturalistic at-home free play sessions in a remote setting.

Beyond simultaneity: Temporal interdependence of behavior is key to affiliative effects of interpersonal synchrony in children

Interpersonal synchrony (IPS) is the temporal coordination of behavior during social interactions. IPS acts as a social cue signifying affiliation both when children witness IPS between others and when they experience it themselves. However, it is unclear which temporal qualities of IPS produce these effects and why. We hypothesized that both the simultaneity and temporal regularity of partners' actions would influence affiliation judgments and that subjective perceptions of IPS ("togetherness") would play a role in mediating these relations. In two online tasks, children aged 4 to 11 years listened to a pair of children tapping (witnessed IPS; n = 68) or themselves tapped with another child (experienced IPS; n = 63). Tapping partners were presented as real, but the sounds attributed to them were computer generated so that their temporal relations could be experimentally manipulated. The simultaneity and regularity of their tapping was systematically manipulated across trials. For witnessed IPS, 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 IPS were found in the experienced IPS condition. Our findings suggest that both the simultaneity and regularity of partners' actions influence children's affiliation judgments when witnessing IPS 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 IPS.

Can rhythm-mediated reward boost learning, memory, and social connection? Perspectives for future research

Studies of rhythm processing and of reward have progressed separately, with little connection between the two. However, consistent links between rhythm and reward are beginning to surface, with research suggesting that synchronization to rhythm is rewarding, and that this rewarding element may in turn also boost this synchronization. The current mini review shows that the combined study of rhythm and reward can be beneficial to better understand their independent and combined roles across two central aspects of cognition: 1) learning and memory, and 2) social connection and interpersonal synchronization; which have so far been studied largely independently. From this basis, it is discussed how connections between rhythm and reward can be applied to learning and memory and social connection across different populations, taking into account individual differences, clinical populations, human development, and animal research. Future research will need to consider the rewarding nature of rhythm, and that rhythm can in turn boost reward, potentially enhancing other cognitive and social processes.

Musical engagement as a duet of tight synchrony and loose interpretability

Joint engagement in music often facilitates positive social interaction, effectively shifting participants' perspective from the individual to the collective. The result is tight coordination and uniformity between participants, but at the same time, also remarkable flexibility and creativity. How does music achieve such a fine balance between the strict alignment necessary for coordination, and the substantial latitude necessary for experimentation? To address this question, I propose to analyze joint music engagement within the tight-loose theoretical framework broadly used in the social sciences. Tight-loose theory was originally developed for distinguishing between two archetypical cultural tendencies. On the one hand, tightness, which denotes stringent adherence to social norms, and on the other hand, looseness, which refers to a more flexible and less restrictive attitude towards norms. I posit that the flexible form of collaboration characteristic of musical interaction is due to a coexistence of tightness and looseness within joint engagement in music. I argue that the tight aspects of music can be attributed to its rhythmic structure, which requires continuous and precise temporal alignment between participants. Indeed, when experienced on its own, outside of a musical context, interpersonal synchrony has been repeatedly shown to enhance diverse positive social capacities such as bonding, collaboration and affiliation between interacting individuals, but at the expense of increasing conformity, blind obedience and even hostility towards non-group members. These effects are consistent with synchrony driving a tight interaction, inducing a sense of common group membership (CGM), which can endow music with necessary rigor and order. In contrast, the loose side of music may pertain to the ambiguity in meaning and intention expressed by music, which leaves ample room for interpretation and improvisation. I thus propose that the combined tight-loose nature of music, can simultaneously enhance positive social behaviors and reduce negative ones, leading to a tolerant form of group membership (TGM).

Musical groove shapes children's free dancing

The drive to move to music is evident across a variety of contexts, from the simple urge to tap our toe to a song on the radio, to massive crowds dancing in time at a rock concert. Though seemingly effortless, beat synchronization is difficult to master and children are often poor beat synchronizers. Nevertheless, auditory-motor integration is fundamental for many daily processes, such as speech. A topic that has been relatively understudied concerns how stimulus properties affect young children's movement in responses to auditory stimuli. In the present study, we examined how musical groove (adult-rated desire to move) affected 3.0- to 6.9-year-old children's free dancing in the comfort of their home (n = 78). In the high groove conditions, children danced more and with more energy compared to the low groove conditions. Moreover, in the high groove condition, children's movement tempos corresponded better with the tempos of the music. Results point to early childhood sensitivity to the musical features that motivate adults to move to music. High groove music may therefore prove especially effective at facilitating early auditory-motor integration. A video abstract of this article can be viewed at https://youtu.be/vli0-6N12Ts.

Investigating the effect of synchronized movement on toddlers' word learning

The effect of interpersonal behavioral synchrony on children's behavior is an emerging field rich with research potential. While studies demonstrate its effect on affiliative and prosocial outcomes, the role of synchronized movement on children's specific learning outcomes has not yet been investigated experimentally. One possibility is that synchrony, as a coordinated social activity, encourages perceived social bonds, leading to heightened attention, and better information retention. Equally likely is that physiological, rather than social learning, mechanisms mediate the effect, given the previously demonstrated role of autonomic arousal in attentional fluctuations, cognitive engagement, problem solving, exploration, and curiosity. The present study investigated the behavioral and physiological effects of synchrony conceptualized as induced, interpersonal, behavioral, movement-based interaction, on word learning in 2.5-year-old children. In a laboratory experiment, toddlers engaged in either a synchronous or an asynchronous movement-based interaction with an adult experimenter while listening to an upbeat children's song. After the (a)synchronous movement episode, the same experimenter engaged children in a word learning task. During the (a)synchrony and learning phases, children's physiological arousal was continuously recorded, resulting in heart rate and skin conductance response measures. Following a caregiver-child free play break, children were tested on their novel word retention. The results indicated that children learned novel labels at equal rates during the learning phase in both conditions, and their retention at test did not differ between conditions: although above chance retention of novel labels was found only following the synchronous, but not the asynchronous episode, the cross-episode comparisons did not reach statistical significance. Physiological arousal indices following the (a)synchrony episode did not differ between conditions and did not predict better word learning, although skin conductance response was higher during the learning than the movement episode. This study contributes to our understanding of the underlying cognitive and physiological mechanisms of interpersonal behavioral synchrony in the knowledge acquisition domain and paves the way to future investigations.

Judgment of togetherness in performances by musical duos

Musicians experience varying degrees of togetherness with their co-performers when playing in ensembles. However, little is known about how togetherness is experienced by audiences and how interpersonal dynamics in body motion and sound support the judgment of togetherness. This research investigates audience sensitivity to audio and visual markers of interperformer coordination and expressivity in ensembles, in relation to modality of stimulus presentation and audience music background. A set of duo ensemble performances, comprising motion capture recordings of the musicians' upper bodies and instruments, were presented to participants with varying music background, including novices and semi-professional musicians. Participants were required to: (i) watch and listen, (ii) only watch, and (iii) only listen to the selected recordings, whilst providing dynamic ratings of how much togetherness between musicians they perceived. Results demonstrate that sound intensity and similarity in right arm motion (quantified using cross-wavelet transform analysis) were significant predictors of rated togetherness in novices, whilst sound synchronization and chest motion coordination predicted togetherness responses in semi-professional musicians. These results suggest the relevance of the quality of body motion coordination and of certain features of the audio outputs in the audience perception of togetherness. This research contributes to a better understanding of the perceptual mechanisms supporting socio-cognitive judgments of joint action activities.

Creativity and tradition: Music and bifocal stance theory

We argue that music can serve as a time-sensitive lens into the interplay between instrumental and ritual stances in cultural evolution. Over various timescales, music can switch between pursuing an end goal or not, and between presenting a causal opacity that is resolvable, or not. With these fluctuations come changes in the motivational structures that drive innovation versus copying.

Children's perception of interpersonal coordination during joint painting

Interpersonal coordination is important for many joint activities. A special case of interpersonal coordination is synchronization, which is required for the performance of many activities, but is also associated with diverse positive social and emotional attributes. The extent to which these effects are due to the reliance on synchrony for task performance or to its specific rhythmic characteristics, is not clear. To address these questions, we considered a more general form of interpersonal coordination, implemented during joint artmaking. This is a non-typical context for interpersonal coordination, not required for task success, and smoother and more loosely-structured than more standard forms of synchronous coordination. Therefore, comparing interpersonal coordination with non-coordination during shared painting, could help reveal general social-emotional reactions to coordination. To gain a more 'naïve' perspective we focused on children, and staged coordinated and non-coordinated art interactions between an adult and a child, asking child observers to judge various variables reflecting the perceived bond between the painters. We found an overall stronger perceived bond for the coordination condition. These results demonstrate that even a non-typical form of interpersonal coordination could be attributed with positive social and emotional qualities, a capacity revealed already in childhood, with possible implications for development.

Individuating multiple (not one) persons reduces implicit racial bias

Individuation training that helps humans see multiple other-race targets as distinct rather than as interchangeable can reduce children’s implicit racial bias in the form of more negative other-race associations than own-race associations. However, little is known about which aspects of these interventions are critical for their effectiveness. The present research examines whether children need to learn to differentiate among multiple other-race individuals for these interventions to reduce their level of implicit racial bias, or whether differentiating a single other-race individual is sufficient. We addressed this question among 4-to-6-year-old Chinese children (N = 66, 31 girls) who engaged in coordinated movement with Black instructors for 2 min. There were two between-subject conditions: in a differentiation condition, there were four different Black instructors, and children had to learn to tell them apart, and in a no-differentiation condition, there was only one Black instructor. Implicit bias was measured using the IRBT, an implicit association test that was developed based on the IAT but is appropriate for young children. We found a reduction in implicit bias against Black people after this interaction in the differentiation condition, but not in the no-differentiation condition. These findings suggest that learning to differentiate among multiple other-race individuals plays a critical role in reducing children’s implicit racial bias.

The Components of Interpersonal Synchrony in the Typical Population and in Autism: A Conceptual Analysis

Interpersonal synchrony – the tendency for social partners to temporally co-ordinate their behaviour when interacting – is a ubiquitous feature of social interactions. Synchronous interactions play a key role in development, and promote social bonding and a range of pro-social behavioural outcomes across the lifespan. The process of achieving and maintaining interpersonal synchrony is highly complex, with inputs required from across perceptual, temporal, motor, and socio-cognitive domains. In this conceptual analysis, we synthesise evidence from across these domains to establish the key components underpinning successful non-verbal interpersonal synchrony, how such processes interact, and factors that may moderate their operation. We also consider emerging evidence that interpersonal synchrony is reduced in autistic populations. We use our account of the components contributing to interpersonal synchrony in the typical population to identify potential points of divergence in interpersonal synchrony in autism. The relationship between interpersonal synchrony and broader aspects of social communication in autism are also considered, together with implications for future research.

Cooperation with partners of differing social experience: An fNIRS-based hyperscanning study

Previous studies have shown the brain synchronization of all team members while completing a collaborative task. Moreover, this effect is influenced by a team's compositional elements, such as gender (opposite or same) or relationships (i.e., friends, lovers, or strangers) among team members. However, whether interpersonal brain synchronization (IBS) is affected by team members' experience, as well as the temporal dynamics of such brain synchronization, remains to be investigated. In the current study, we combined behavioral methods and functional near-infrared spectroscopy-based hyperscanning to examine the effect of member experience on team cooperation by an adopted continuous joint drawing task with 21 student-student dyads (S-S dyads) and 22 teacher-student dyads (T-S dyads). The results revealed that team members with differing experiences (T-S dyads) perform better than those with similar ones (S-S dyads). Moreover, we observed IBS in the left frontopolar region (channel 11). However, we did not observe significant changes of the task-related IBS across time. Besides, IBS was negatively correlated with the participants' behavioral performance. Our findings demonstrate the importance of social experience in teamwork in the real world and suggest a possible mechanism for cooperation from a temporal and spatial perspective.

A syncing feeling: reductions in physiological arousal in response to observed social synchrony

Synchronized movements are often key elements in activities where social bonding and emotional connection are a shared goal, such as religious gatherings, sporting events, parties and weddings. Previous studies have shown that synchronous movements enhance prosocial attitudes and affiliative behaviors. Similarly, observers attribute more social closeness to people moving synchronously together than people moving asynchronously. The mechanisms by which synchrony modulates these attributions are not well understood. In the present study, we ask whether viewing synchronous activities influences physiological arousal as measured by skin conductance and whether group size impacts this effect. Undergraduates viewed a series of short videos depicting people moving either (1) in or out of synchrony with each other and (2) in a large or small group. Participants’ skin conductance was measured. Change in skin conductance levels and response counts were attenuated while watching synchronous movement, but only in the large-group condition. Post-hoc analyses suggest that viewer enjoyment/interest in the large-group synchronous videos mediated this association for phasic skin conductance responses, but no evidence of mediation was found for tonic skin conductance levels. Results extend previous research on affiliative effects of first-person interpersonal synchrony and demonstrate that watching others moving synchronously has an attenuating effect on observers’ physiological state.

Interpersonal coordination in three-year-old children: Functions, morphology, and temporality

The temporal dimension of interpersonal macro- and micro-coordinations between young children and social partners, as well as its functions, has been well documented. However, the different morphologies that bodily micro-coordination can adopt during these interactions have received considerably less attention. This research studied the temporality and morphology of spontaneous child-adult micro-coordinations and their associated functions. For this purpose, three-year-old children (N = 35) were randomly assigned to storytelling sessions based on emotional or referential stories. Using motion capture technology, we traced rapid and spontaneous coordinations between torso movements, ranging from 0 to 1000 milliseconds. Results show that both mirror-like and anatomical coordinations spontaneously emerge in interactions between 3-year-old children and unfamiliar adults. Importantly, slightly delayed in time, mirror-like coordinations predominantly occur in emotional interactions, while zero-lag, anatomical coordinations occur in referential interactions. These results suggest that these morphologies might indeed inform different functions of coordination, as previously theorized in the literature. The evidence found could contribute to a better understanding of how interpersonal coordination shapes social interaction very early in development.

Flourishing in Resonance: Joint Resilience Building Through Music and Motion

Worldwide, children face adverse childhood experiences, being exposed to risks ranging from, exposure to political violence and forced migration over the deleterious effects of climate change, to unsafe cultural practices. As a consequence, children that seek refuge or migrate to European countries are extremely vulnerable, often struggling with integration in school, peer community, and their broader social circle. This multifaceted struggle can derive from external factors, such as the adaptation process and contact with other children, or internal factors such as the fears and trauma that every child carries within them since they departed from their homeland. To bounce, grow, connect, and create in both adversity and opportunity, children need to build resilience, i.e., the capacity of an individual to maintain stable psychological functioning throughout the course of adversity. On the one hand, building resilience requires developing a set of individual skills (internal protective factors), such as self-control, emotion regulation, self-esteem, and agency. On the other hand, building resilience involves developing social skills (external protective factors), connection, and close relationships. In this theoretical contribution, we review and map existing research to argue that activities based on the combination of music and movement has a strong potential to intensively build resilience. First, we connect the concepts of resilience and eudaimonia, based on the protective factors and key components of resilience. Then we discuss how music and movement, separately, may contribute to building resilience. Next, drawing on the basic mechanisms of musical sense-making, we argue that through combining music and movement, children engage in empowering musical sense-making processes that support building resilience, and in this way, support them to grow together and deeply experience eudaimonic values such as self-awareness, confidence and self-esteem, personal autonomy, connection, belonging, and bonding. Finally, we connect theory to practice. Based on the presented theoretical elaborations and on the authors’ experience as practitioners, we propose a set of guiding principles for the design of movement-based musical activities that foster the internal and external factors necessary to build resilience.

Group cohesiveness in children free-play activity: A social network analysis

Despite the ethnic diversity and presence of Amerindian communities in all Brazilian states, the indigenous population suffers from a long process of invisibility and stereotyping. Aiming to increase interethnic associations, together with Mbya-Guarani leaders we promoted interventions in which indigenous and non-indigenous children shared free playtime. We hypothesised that free play activity would stimulate group cohesiveness, mitigating ethnic group avoidance in children's playgroups. Twenty-one Mbya-Guarani and 61 non-indigenous children participated in two "Encounters for Play." We recorded children's social interactions during the free playtimes. We selected the first and last 10 minutes of each encounter and performed scans every 30s registering spatial proximity (children who were up to 1 m of each other) and play. Then, we applied Social Network Analysis to explore the children's association pattern at the beginning and end of playtime in each encounter. Our results show free play activity was effective in stimulating group cohesiveness. Children' proximity association pattern and playgroup configuration changed between clips, and there was a significant correlation between both categories' associations. We conclude that the encounters have potential applicability as an intervention to mitigate ethnic group avoidance in children.

Rhythmic Chanting and Mystical States across Traditions

Chanting is a form of rhythmic, repetitive vocalization practiced in a wide range of cultures. It is used in spiritual practice to strengthen community, heal illness, and overcome psychological and emotional difficulties. In many traditions, chanting is used to induce mystical states, an altered state of consciousness characterised by a profound sense of peace. Despite the global prevalence of chanting, its psychological effects are poorly understood. This investigation examined the psychological and contextual factors associated with mystical states during chanting. Data were analyzed from 464 participants across 33 countries who regularly engaged in chanting. Results showed that 60% of participants experienced mystical states during chanting. Absorption, altruism, and religiosity were higher among people who reported mystical states while chanting compared to those who did not report mystical states. There was no difference in mystical experience scores between vocal, silent, group or individual chanting and no difference in the prevalence of mystical states across chanting traditions. However, an analysis of subscales suggested that mystical experiences were especially characterised by positive mood and feelings of ineffability. The research sheds new light on factors that impact upon chanting experiences. A framework for understanding mystical states during chanting is proposed.

Infant-adult synchrony in spontaneous and nonspontaneous interactions

Infant-adult synchrony has been reported through observational and experimental studies. Nevertheless, synchrony is addressed differently in both cases. While observational studies measure synchrony in spontaneous infant-adult interactions, experimental studies manipulate it, inducing nonspontaneous synchronous and asynchronous interactions. A still unsolved question is to what extent differ spontaneous synchrony from the nonspontaneous one, experimentally elicited. To address this question, we conducted a study to compare synchrony in both interactional contexts. Forty-three 14-month-old infants were randomly assigned to one of two independent groups: (1) the spontaneous interaction context, consisting of a storytime session; and (2) the nonspontaneous interaction context, where an assistant bounced the infant in synchrony with a stranger. We employed an optical motion capture system to accurately track the time and form of synchrony in both contexts. Our findings indicate that synchrony arising in spontaneous exchanges has different traits than synchrony produced in a nonspontaneous interplay. The evidence presented here offers new insights for rethinking the study of infant-adult synchrony and its consequences on child development.

A Qualitative Study of the Views of Patients With Medically Unexplained Symptoms on The BodyMind Approach®: Employing Embodied Methods and Arts Practices for Self-Management

The arts provide openings for symbolic expression by engaging the sensory experience in the body they become a source of insight through embodied cognition and emotion, enabling meaning-making, and acting as a catalyst for change. This synthesis of sensation and enactive, embodied expression through movement and the arts is capitalized on in The BodyMind Approach^® (TBMA). It is integral to this biopsychosocial, innovative, unique intervention for people suffering medically unexplained symptoms (MUS) applied in primary healthcare. The relevance of embodiment and arts practices in TBMA are discussed in relation to the views of participants in the pursuit of self-management. If widely employed TBMA could have an enormous impact, reach, and significance for patients and global health services. This original pre-clinical trial of qualitative research reports on the perceptions of participant patients with generic MUS, a world-wide issue usually treated by either psychological therapy or physiotherapy. TBMA is not a therapy but a health education program founded upon the concept of an integration of psychological elements with physiological, bodily, and sensory experiences. Thematic analysis of qualitative data sets from open-ended questions in semi-structured interviews and a written questionnaire post intervention is presented. Five aspects which appear to be key to learning self-management were derived from analyzing the data: (1) body with mind connections; (2) importance of facilitation; (3) potential benefits; (4) preparedness for change; (5) self-acceptance/compassion. This article advances the discourse on the nature of self-management for MUS through changing the mind-set and the relationship participants have with their bodily symptom/s through employing embodied methods and arts practices, challenging current, and solely verbal, psychological conceptual frameworks. Rigor lies in the method of data analysis using cross verification of credibility between reported findings and scrutiny by stakeholders. We conclude that facilitated TBMA groups employing embodied methods and arts practices can act as a method for developing the self-management of MUS and improving wellbeing.

Music as a coevolved system for social bonding

Why do humans make music? Theories of the evolution of musicality have focused mainly on the value of music for specific adaptive contexts such as mate selection, parental care, coalition signaling, and group cohesion. Synthesizing and extending previous proposals, we argue that social bonding is an overarching function that unifies all of these theories, and that musicality enabled social bonding at larger scales than grooming and other bonding mechanisms available in ancestral primate societies. We combine cross-disciplinary evidence from archaeology, anthropology, biology, musicology, psychology, and neuroscience into a unified framework that accounts for the biological and cultural evolution of music. We argue that the evolution of musicality involves gene-culture coevolution, through which proto-musical behaviors that initially arose and spread as cultural inventions had feedback effects on biological evolution due to their impact on social bonding. We emphasize the deep links between production, perception, prediction, and social reward arising from repetition, synchronization, and harmonization of rhythms and pitches, and summarize empirical evidence for these links at the levels of brain networks, physiological mechanisms, and behaviors across cultures and across species. Finally, we address potential criticisms and make testable predictions for future research, including neurobiological bases of musicality and relationships between human music, language, animal song, and other domains. The music and social bonding (MSB) hypothesis provides the most comprehensive theory to date of the biological and cultural evolution of music.

The cultural evolutionary trade-off of ritualistic synchrony

From Australia to the Arctic, human groups engage in synchronous behaviour during communal rituals. Because ritualistic synchrony is widespread, many argue that it is functional for human groups, encouraging large-scale cooperation and group cohesion. Here, we offer a more nuanced perspective on synchrony's function. We review research on synchrony's prosocial effects, but also discuss synchrony's antisocial effects such as encouraging group conflict, decreasing group creativity and increasing harmful obedience. We further argue that a tightness-looseness (TL) framework helps to explain this trade-off and generates new predictions for how ritualistic synchrony should evolve over time, where it should be most prevalent, and how it should affect group well-being. We close by arguing that synthesizing the literature on TL with the literature on synchrony has promise for understanding synchrony's role in a broader cultural evolutionary framework. This article is part of the theme issue 'Ritual renaissance: new insights into the most human of behaviours'.

Developmental trajectory of interpersonal motor alignment: Positive social effects and link to social cognition

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Interpersonal motor alignment (IMA) has positive effects on healthy social life.

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IMA - mimicry, synchrony, automatic imitation - is studied throughout development.

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It relies on motor resonance brain mechanisms identified throughout development.

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It is modulated by contextual and personal factors.

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IMA is underinvestigated in adolescence, yet it may aid to enhance resilience.

Interpersonal motor alignment is a ubiquitous behavior in daily social life. It is a building block for higher social cognition, including empathy and mentalizing and promotes positive social effects. It can be observed as mimicry, synchrony and automatic imitation, to name a few. These phenomena rely on motor resonance processes, i.e., a direct link between the perception of an action and its execution. While a considerable literature debates its underlying mechanisms and measurement methods, the question of how motor alignment comes about and changes in ontogeny all the way until adulthood, is rarely discussed specifically. In this review we will focus on the link between interpersonal motor alignment, positive social effects and social cognition in infants, children, and adolescents, demonstrating that this link is present early on in development. Yet, in reviewing the existing literature pertaining to social psychology and developmental social cognitive neuroscience, we identify a knowledge gap regarding the healthy developmental changes in interpersonal motor alignment especially in adolescence.

Shaping children's racial bias through interpersonal movement

The early emergence of racial biases points to the urgent need to understand how interpersonal experiences might shape them. We examined whether interpersonal movement shapes racial biases among 4- to 6-year-old Chinese children who had no prior contact with Black people. In Experiment 1 (N = 134), children played a musical game, moving either in or out of synchrony with a Chinese or Black adult. In Experiment 2 (N = 30), children were merely exposed to a Black adult. Across the two experiments, we found that synchronous movement increased children's feeling of social closeness toward their movement partner to a greater extent than asynchronous movement regardless of the partner's race. After moving in or out of synchrony with the Chinese adult, synchrony selectively increased children's explicit positive pro-own-race bias. However, after moving in or out of synchrony with the Black adult, both movement styles reduced explicit anti-other-race bias. Experiment 2 ruled out mere exposure to an other-race person as a driving factor for these effects. Our results suggest that musical engagement may be a promising intervention for reducing negative intergroup biases.

Human Social Evolution: Self-Domestication or Self-Control?

The self-domestication hypothesis suggests that, like mammalian domesticates, humans have gone through a process of selection against aggression - a process that in the case of humans was self-induced. Here, we extend previous proposals and suggest that what underlies human social evolution is selection for socially mediated emotional control and plasticity. In the first part of the paper we highlight general features of human social evolution, which, we argue, is more similar to that of other social mammals than to that of mammalian domesticates and is therefore incompatible with the notion of human self-domestication. In the second part, we discuss the unique aspects of human evolution and propose that emotional control and social motivation in humans evolved during two major, partially overlapping stages. The first stage, which followed the emergence of mimetic communication, the beginnings of musical engagement, and mimesis-related cognition, required socially mediated emotional plasticity and was accompanied by new social emotions. The second stage followed the emergence of language, when individuals began to instruct the imagination of their interlocutors, and to rely even more extensively on emotional plasticity and culturally learned emotional control. This account further illustrates the significant differences between humans and domesticates, thus challenging the notion of human self-domestication.

Prior physical synchrony enhances rapport and inter-brain synchronization during subsequent educational communication

Physical synchrony has been suggested to have positive effects on not only concurrent but also subsequent communication, but the underlying neural processes are unclear. Using functional near-infrared spectroscopy (fNIRS) hyperscanning, we tested the effects of preceding physical synchrony on subsequent dyadic teaching-learning communication. Thirty-two pairs of participants performed two experimental sessions. In each session, they underwent a rhythmic arm movement block with synchronous or asynchronous conditions, and then taught/learned unknown words to/from each other according to a given scenario. Neural activities in their medial and left lateral prefrontal cortex (PFC) were measured and inter-brain synchronization (IBS) during the teaching-learning blocks was evaluated. Participants rated their subjective rapport during the teaching-learning blocks, and took a word memory test. The analyses revealed that (1) prior physical synchrony enhanced teacher-learner rapport; (2) prior physical synchrony also enhanced IBS in the lateral PFC; and (3) IBS changes correlated positively with rapport changes. Physical synchrony did however not affect word memory performance. These results suggest that IBS can be useful to measure the effects of social-bonding facilitation activities for educational communication.

Social motor coordination during adult-child interactions

Social motor coordination (SMC) pertains to the timing of contingent movements during social interactions and is of high relevance for successful social and musical interactions. Semi-automated, objective methods are increasingly being used to analyze SMC, though it is unclear if these methods are feasible in naturalistic settings with young children. The purpose of the current preliminary study was to explore SMC in adult-child dyads during semi-structured social interactions. Thirteen dyads (mean age of children = 36 months) participated in a predictable turn-taking task from a social communication assessment, and a semi-automated frame-difference approach was used to capture movement activity. Relative timing and activity approaches revealed that, while there is some evidence of co-occurring movement, the dyad predominantly exhibited patterns of responsive movement activity (e.g., turn taking or alternating movement) consistent with the activity's structure. Future work may extend these approaches to social musical interactions in order to examine movement coordination and prosocial behavior during joint music-making activities with young children.

Rhythm and melody as social signals for infants

Infants typically experience music through social interactions with others. One such experience involves caregivers singing to infants while holding and bouncing them rhythmically. These highly social interactions shape infant music perception and may also influence social cognition and behavior. Moving in time with others-interpersonal synchrony-can direct infants' social preferences and prosocial behavior. Infants also show social preferences and selective prosociality toward singers of familiar, socially learned melodies. Here, we discuss recent studies of the influence of musical engagement on infant social cognition and behavior, highlighting the importance of rhythmic movement and socially relevant melodies.

How interpersonal synchrony facilitates early prosocial behavior

When infants and children affiliate with others, certain cues may direct their social efforts to 'better' social partners. Interpersonal synchrony, or when two or more people move together in time, can be one such cue. In adults, experiencing interpersonal synchrony encourages affiliative behaviors. Recent studies have found that these effects also influence early prosociality-for example, 14-month-olds help a synchronous partner more than an asynchronous partner. These effects on helping are specifically directed to the synchronous movement partner and members of that person's social group. In older children, the prosocial effects of interpersonal synchrony may even cross group divides. How synchrony and other cues for group membership influence early prosociality is a promising avenue for future research.

Joint Rhythmic Movement Increases 4-Year-Old Children's Prosocial Sharing and Fairness Toward Peers

The allocation of resources to a peer partner is a prosocial act that is of fundamental importance. Joint rhythmic movement, such as occurs during musical interaction, can induce positive social experiences, which may play a role in developing and enhancing young children's prosocial skills. Here, we investigated whether joint rhythmic movement, free of musical context, increases 4-year-olds' sharing and sense of fairness in a resource allocation task involving peers. We developed a precise procedure for administering joint synchronous experience, joint asynchronous experience, and a baseline control involving no treatment. Then we tested how participants allocated resources between self and peer. We found an increase in the generous allocation of resources to peers following both synchronous and asynchronous movement compared to no treatment. At a more theoretical level, this result is considered in relation to previous work testing other aspects of child prosociality, for example, peer cooperation, which can be distinguished from judgments of fairness in resource allocation tasks. We draw a conceptual distinction between two types of prosocial behavior: resource allocation (an other-directed individual behavior) and cooperation (a goal-directed collaborative endeavor). Our results highlight how rhythmic interactions, which are prominent in joint musical engagements and synchronized activity, influence prosocial behavior between preschool peers.