Musical ensemble performance constitutes a refined form of joint action that involves the non-verbal communication of information about musical structure and expressive intentions via co-performers’ sounds and body movements. Successful musical communication requires co-performers to coordinate their actions across multiple musical dimensions (pitch and rhythm), timescales (expressive micro-timing versus large-scale tempo changes), sensory modalities (auditory and visual) and modes of interaction (unison versus complementary action). From a psychological perspective, ensemble performance necessitates precise yet flexible interpersonal coordination at the level of sensorimotor, cognitive, emotional and social processes. The current chapter addresses how such interpersonal coordination is facilitated by representations of shared performance goals, which are consolidated during preparation for joint musical performance. During actual performance, these shared goal representations interact with online sensorimotor and cognitive processes that allow co-performers to anticipate, attend and adapt to each other’s actions in real time. Studies employing behavioral and brain methods provide evidence for three functional characteristics of shared musical representations. First, shared representations involve the integration of information related to one’s own part, others’ parts and the joint action outcome, while maintaining a distinction between self and other. Second, self, other and joint action outcomes are represented in predictive internal models. Third, internal models recruit the motor system to simulate self- and other-produced actions at multiple hierarchical levels. Shared musical representations thus facilitate exquisite real-time interpersonal coordination by dynamically embodying intended action outcomes related to the self, others and the ensemble as a whole.

The human ability to predict and interpret others’ intentions is crucial to social life. The purpose of this chapter is to consider the proposition that intentions can be understood from observing others’ movements. To this end, we first focus on experimental evidence showing that individual, social and communicative intentions ‘shape’ movement kinematics. Next, we review recent work suggesting that during action observation humans are capable of picking up intention information and using it to predict others’ behavior. In the third section, we address the neural mechanisms that mediate the ability to read intention from movement observation. Based on preliminary data, we argue that mirror neuron areas are sensitive to intention information conveyed by movement kinematics. Finally, we discuss the hypothesis that a deficit in this ability might account for the difficulties in social interaction reported in autism spectrum disorders.

Music production and perception and human social understanding are linked in many ways. Producing and enjoying music appears unique to humans, and debate surrounds the topic of music’s function, especially in relation to its evolutionary origins. Here, we discuss links between music and sociality, and how insights from the unique fields of music neuroscience and social neuroscience can be combined to understand this relationship.

This chapter will begin with a focus on a particular subtopic within the shared representations research domain: imitation. Imitation occurs when the perception of another’s actions causes the activation of the corresponding motor representation in the observer. Thus imitation relates to shared representations in that it concerns the activation of a self-related representation by an other-related representation. In this chapter, I will use examples from the autism spectrum conditions (ASCs) literature to argue that if either the self- or other-related representation is atypical this can result in atypical imitation. In other words, if action observation or action execution mechanisms are atypical, then imitation will be affected. I will conclude this chapter by drawing on research that extends this logic to other sociocognitive domains such as empathy and to conditions such as schizophrenia and alexithymia.

Three main views of the primate motor cortex have been proposed over the 140 years of its study. These views are not necessarily incompatible. In the homunculus view, the motor cortex functions as a rough map of the body’s musculature. In the population-code view, populations of broadly-tuned neurons combine to specify hand direction or some other parameter of movement. In the recently proposed action map view, common actions in the movement repertoire are emphasized in different regions of cortex. In the action map view, to fully understand the organization of the motor cortex, it is necessary to study the structure and complexity of the movement repertoire and understand how that statistical structure is mapped onto the cortical surface. This chapter discusses the action map in the primate brain and how some of the complex actions represented there may play a role in social behavior.

Shared representations and coordinated action, in both team sports and for individuals with specific roles, have a big impact on performance outcomes in a wide range of sporting domains. Within team sports, perceptual and decision-making issues are key; performers must both see things in similar ways and make similar or mutually compatible decisions if appropriate action is to be taken and performance optimised. To do this, an athlete must interpret perceptual information effectively, applying an implicit ‘weighting scale’ to determine the pertinence of key factors. Such a commonality of perception across a team allows the formation of a shared mental model (SMM) through a process of both time-pressured and deliberate thinking and action, along with appropriate feedback. As individuals, referees and match officials must apply a consistent weighting scale to both formal decision making (i.e. applying the rules of the game) and more informal game management. The implementation of SMMs has been shown to increase consistency and coherence in leading referees, with shared representations resulting from both training and more ‘natural’ processes. Selection panels have also demonstrated substantial and rapid improvements in coherence, through exposing and agreeing operational definitions of key criteria, developing common weighting scales, monitoring and regular feedback. Such shared representations also carry benefits for support personnel within interdisciplinary teams and for team cultures; common features in high performance sport. It is clear that socially based or developed shared representations are crucial to effective performance in sport, and the various examples considered here offer considerable potential for future research.

Human life involves and requires joint action. Coordinating our actions with others not only gives rise to cultural products that individuals could not achieve alone, such as the Egyptian pyramids or the performance of a symphony. Rather, everyday life also has us engage in many joint actions, from folding a sheet together to having a conversation. How do people manage to act together in a coordinated way? In this chapter, we consider this question in terms of the cognitive mechanisms underlying joint action, focusing on real-time interactions in dyads or small groups. To illustrate what we are aiming to explore, think of two people who are loading shopping bags into the trunk of a car. At times, they each take a rather light bag from the shopping cart, move towards the trunk and then coordinate who is setting their bag down first, and where. At other moments, they carry heavy bags together, making sure to lift and set these down at the same time. As this shows, performing a joint action often requires adapting one’s own actions to what another person is doing. In this chapter, we first introduce some key concepts that have been highlighted in previous accounts of joint action, briefly addressing shared intentions, commitment and representations of joint goals. The main part focuses on coordination mechanisms – cognitive processes and mental representations that make performing joint actions of the kind described above possible. Specifically, we will review findings from experimental studies that shed light on general coordination strategies, representations of joint abilities and tasks, mechanisms of predicting own and others’ actions, and non-verbal communication through action. We will conclude by discussing ways in which different coordination mechanisms might be combined to allow co-actors to take on complementary roles.

Perception is solitary. After all, it is the individual alone who feels, hears, tastes, smells and sees. Yet, while the phenomenology of engaging with the world through our senses is restricted to subjective sensations, those sensations are often experienced in a social context. Do social forces change how an individual interacts with the environment and responds to incoming information? We present and discuss a recently discovered phenomenon: people’s eye movements and focus of attention change with their belief that they are looking at objects alone or together with somebody else. Research on ‘joint perception’ provides evidence for the pervasive effect of social context, influencing psychological processes from cognition to low-level perception.

Behavioral synchronization is one mechanism through which people coordinate their behavior in social interactions. Researchers from a wide range of scientific disciplines have examined the social antecedents and consequences of behavioral synchrony. At the core of this research lies the double assumption that people spontaneously synchronize their behavior during social interactions, and that synchronized movement rhythms transform individuals into a social unit. Recent experimental research has started to offer converging support for these theoretical ideas. In the present chapter, we will first define behavioral synchrony and review early research on movement synchrony. Subsequently, we discuss how behavioral synchrony is measured using frame-by-frame analysis, judgments of synchrony by observers, movement tracking devices or automatic motion analysis. We then provide an overview of recent studies on how synchrony emerges, focusing both on a dynamic systems perspective, as a cognitive perspective based on common coding theory. Finally, we review research on the consequences of behavioral synchrony, on the affective, behavioral and cognitive consequences of moving in synchrony. The research discussed in this chapter points towards the fundamental role synchrony plays in social interaction. The tendency to synchronize, together with the emergence of a social unit when individuals move in synchrony, seems to indicate that people have a predisposition to socially connect to others through mutual adaptation of behavioral rhythms.