Centre for Music and Science

This thesis investigates the process termed ‘entrainment’ by which a group of singers can become ‘in time’ or ‘in synchrony’ with each other. Group entrainment is examined through the lenses of a number of disciplines throughout the thesis: ethnography, ethnomusicology, sociology, animal behaviour, complex systems theory, and psychology.
Ch. 1 defines the concepts such as entrainment, chant, ritual, participatory and presentational musics, and the ethnographical method that will be used in this thesis.
Ch. 2 reveals, through an ethnographical survey of the function of group singing in various traditions around the world, that a central purpose of group singing is to form community.
Ch. 3 examines the form of group singing throughout the world, and finds that a general theory of metre, the perceptual basis of entrainment, can be applied to geographically-distinct traditions, but also that some chanting traditions do not need metre for entrainment to be possible.
Ch. 4 contextualises Turner and Durkheim’s community-forming concepts of ‘communitas’ and ‘collective effervescence’ within a particular music anthropology study of the Suyán Indian ‘Mouse Ceremony’ in Amazonia, with reference to the concept of ‘entrainment’.
After the initial ethnographic survey (Chs. 2-4), the rest of the thesis (Chs. 5-8) explores ways of thinking scientifically about the process of group entrainment.
Ch. 5 discusses bottom-up and top-down approaches to understanding group behaviour, with reference to flocking and schooling behaviour in starlings and fish, and chanting and free jazz improvisation in human musical behaviour.
Ch. 6 puts the bottom-up and top-down dialectic in the context of the current entrainment literature, in order to suggest new approaches for investigating entrainment in group contexts.
Ch. 7 reviews the literature surrounding bottom-up aspects of group interaction such as gesture and visual communication, and the top-down influence of group hierarchy, and also inter-group and joint speech forms of entrainment.
The various disciplinary perspectives discussed in previous chapters then provide the basis for an empirical field study in Ch. 8 of group entrainment in Gregorian chant, involving semi-structured interviews with choristers and systematic video analysis of their chanting. The study investigates how these choristers are able to start in synchrony with each other, looking particularly at the role of gesture and metrical perception. I find that no single mode of communication or perception offers an explanation for the precision of onset synchrony on its own, and therefore conclude that group onset synchrony must depend on a combination of many factors.
This thesis moves the study of entrainment further by discussing ways in which we can think about and investigate group, as opposed to dyadic (joint), entrainment. It also shows the importance of combining the insights of both anthropological and scientific approaches when investigating group entrainment.

The human capacity for synchronising body movements to an external rhythmic source enables various group activities, such as music-making and dancing. The present study aimed to investigate the influence of different social contexts on the process of synchronisation, termed `entrainment'. Pairs of human participants were instructed to walk on parallel treadmills under different experimental conditions. In the `separate' (control) condition, participants could not see or hear each other; in the together condition, participants could see and hear each other but were instructed not to converse; finally, in the talking condition, participants conversed with each other. Time series data was extracted from video data obtained by placing a static video camera behind the participants, and the interaction between both participants' footfalls was analysed using circular statistics. It was hypothesised that the degree of synchrony between footfalls would be highest in
the talking condition, lower in the together condition, and non-existent in the separate condition. None of the statistical measures showed signicance for a within-subjects main effect of condition, but almost all measures showed a clear trend in agreement with the hypothesis. It was shown that the degree of interpersonal entrainment was higher when participants talked to each other than when they did not interact. This has implications for the study of the social activity of musicmaking,
and suggests that embodied interpersonal processes must be a focal component of any exploration of human musicality in all its manifestations.

This essay focuses on a particular question in music philosophy and music psychology: Is music’s expressivity a result of judgements we make concerning features of the music or its propensity to arouse emotion in the listener? Whilst concentrating on the way music philosophers approach this question, I will attempt, where appropriate, to situate certain philosophical theories in the context of empirical findings.

This essay will focus on empirical findings of cognitive psychology that examine the synergistic relationship between the auditory and visual domains of film. In cognitive psychology, theories argue that music’s expressivity results from cognitive ‘appraisal’ of musical features considered to have a certain expressive quality, whereas ‘emotivist’ theories claim that music’s expressivity is explained by its propensity to arouse emotion in the listener. However, Jeff Smith has argued that a purely ‘cognitivist’ approach is not adequate for understanding emotional arousal given that spectators make sense of film music’s affective properties on a number of different levels of mental and bodily states, and therefore, these levels are best understood within a combination of cognitivist and emotivist theories of musical affect.

Disagreement between representational and relational views of perception often centres on cases where perceptual content appears to outstrip the information present in the stimulus. However, this debate has centred on vision; auditory perception is less commonly considered in this context. The ‘missing fundamental’ is commonly thought to involve this kind of discrepancy between mind and world, and the content of the pitch percept is often described by inferentialists as having been generated by an act of perceptual inference. However, just what these acts of perceptual inference are supposed to consist in is unclear. In this paper, I formulate a 'job-description' for perceptual inference, as well as examining the motivations for appealing to it, in the case of the missing fundamental. I argue that, contrary to the manner in which it is commonly discussed in the literature, no appeal to perceptual inference is necessary to explain the missing fundamental: I suggest that in the absence of clear evidence that the ‘rule’ governing the system is being represented, and in the presence of a simpler explanation in terms of environmental regularities, we should avoid ascribing inferential capacity. I close by considering objections, and offering replies.

ABSTRACT This paper is a discussion about how the Application Perspective works in practice.1 We talk about values and attitudes to system development and computer systems, and we illustrate how they have been carried out in practice by examples from the Florence project.2 The metaphors ‘utensil’ and ‘epaulet’ refer to questions about how we conceive the computer system we are to design in the system development process. Our experience is that, in the scientific community, technical challenges mean making computer systems that may be characterised as ‘epaulets’: they have technical, fancy features, but are not particularly useful. Making small, simple, but useful computer systems, more like ‘utensils’, does not give as much credit even if the development process may be just as challenging.

Body Moves is a conceptual framework for the bodily metacommunicative (Gill, Kawamori, Katagiri, Shimojima, 2000) or metapragmatic (Mey, 2001) dimensions of human interaction for managing information flow, formation and transformation within interactive settings (Gill, 2001, 2003a, 2003b). Information flow is carried through sequential body moves of action and reaction response, whilst knowledge transformation emerges in parallel coordinated motion (Gill, 2002, 2003b). The process of moving from the state of information flow to knowledge transformation is seen as a process of grounding, where grounding occurs within the integration of the axes of awareness, activity and cognitivity of the tacit and explicit dimensions of human knowing. Managing this flow and formation of knowledge in co-action (Gill, 2003a) is a form of social intelligence, and makes for sustainable communication. This conceptual framework of body moves and tacit knowing is developed in a discussion about cooperative behaviour within design tasks. These tasks involve participants acting upon various interfaces that influence the communicative strategies they use to collaborate with each other. The analysis suggests that mediational interfaces that can support this collaborative behaviour need to handle this pragmatics, and in doing so, the paper contributes to the discussion of pragmatic processes of cognitive technology.

Many authors have argued the need for abroader understanding of context and the situatedness of activity when approaching the evaluation of systems. However, prevailing practice often still tends toward attempting to understand the use of designed artifacts by ...

This chapter presents an analysis of knowledge as a process of tacit knowing embodied in dialogue rather than as a process of information transfer embodied in signal processing (Shannon and Weaver 1949). Within dialogue we acquire knowledge (experiential knowledge, tacit knowing, practical knowledge) through our embodied performance of ’how ’ and ’what’ we know about the communication situation we are in. This embodied performance includes utterances, gestures, movement and modulation of body and voice, as well as mediating artefacts, such as interactive technologies. This chapter explores the implications of this perspective of knowledge for the conception and design of interactive technologies that seek to facilitate joint action and joint attention.

The importance of non verbal communication within the human interface, the point at which interaction occurs, is becoming of increasing significance for natural language pragmatics and the design of interactive systems based upon it. This dimension of communication is essential for an understanding of 'co-presence' (Good 1996), which is an essential component of human understanding. Co-presence denotes simply how we are present to each other, be this in the same physical space or in differing physical spaces. Being present may be described as a precondition for communication, and the nature of this precondition has a bearing on how we coordinate with each other.

What constitutes our human capacity to engage and be in the same frame of mind as another human? How do we come to share a sense of what ‘looks good’ and what ‘makes sense’? How do we handle differences and come to coexist with them? How do we come to feel that we understand what someone else is experiencing? How are we able to walk in silence with someone familiar and be sharing a peaceful space? All of these aspects are part of human ‘interaction’. In designing interactive technologies designers have endeavoured to explicate, analyse and simulate, our capacity for social adaptation. Their motivations are mixed and include the desires to improve efficiency, improve consumption, to connect people, to make it easier for people to work together, to improve education and learning. In these endeavours to explicate, analyse and simulate, there is a fundamental human capacity that is beyond technology and that facilitates these aspects of being, feeling and thinking with others. That capacity, we suggest, is human entrainment. This is our ability to coordinate the timing of our behaviours and rhythmically synchronise our attentional resources. Expressed within the movements of our bodies and voices, it has a quality that is akin to music. In this paper, disparate domains of research such as pragmatics, social psychology, behaviourism, cognitive science, computational linguistics, gesture, are brought together, and considered in light of the developments in interactive technology, in order to shape a conceptual framework for understanding entrainment in everyday human interaction.

Skilled cooperative action means being able to understand the com- municative situation and know how and when to respond appropriately for the purpose at hand. This skill is of the performance of knowledge in co-action and is a form of social intelligence for sustainable interaction. Social intelligence, here, denotes the ability of actors and agents to manage their relationships with each other. Within an environment we have people, tools, artefacts and tech- nologies that we engage with. Let us consider all of these as dynamic repre- sentations of knowledge. When this knowledge becomes enacted, i.e., when we understand how to use it to communicate effectively, such that it becomes invisible to us, it becomes knowledge in co-action. A challenge of social intel- ligence design is to create mediating interfaces that can become invisible to us, i.e., as an extension of ourselves. In this paper, we present a study of the way people use surfaces that afford graphical interaction, in collaborative design tasks, in order to inform the design of intelligent user interfaces. This is a descriptive study rather than a usability study, to explore how size, orientation and horizontal and vertical positioning, influences the functionality of the sur- face in a collaborative setting.

Our everyday interactions increasingly involve both embodied face-to-face communication and various forms of mediated and distributed communication such as email, skype, and facebook. In daily face-to-face commu- nications, we are connected in rhythm and synchrony at multiple levels ranging from the moment-by-moment continuity of timed syllables to emergent body and vocal rhythms of pragmatic sense-making. Our human capacity to synchronize with each other may be essential for our survival as social beings. Moving our bodies and voices together in time embodies a potent pragmatic purpose that of being together. In this synchrony of self with other, witnessing and being present become part of each other. There is growing research into how rhythm and synchrony operate in embodied face-to-face interaction and this provides parameters for investigating the relations and differences in how we connect and are socially present in the embodied and distributed settings, and understanding the effect of one setting upon the other. This paper explores the arena of research into rhythm in human interaction, musical and linguistic, with a focus on the movements of body and voice. It draws together salient issues and ideas that would form the basis for a framework of rhythm in embodied interaction.

The engagement space (Gill, Kawamori, Katagiri, Shimojima, 2000) is the arena within which coordinated body movements take place in interactive settings. It is a commitment on the part of its participants to be together, or to be present. Previous work on the metacommunicative body dynamics of the engagement space showed that composite dialogue acts of gesture, speech, and silence (Body Moves (BM)) play an important role in the flow of information in interaction. One of the Body Moves, namely the Parallel Coordinated Move, was difficult to categorise according to the patterns of metacommunicative body motion that involved a clear rhythmic sequential motion of action and reaction, and was hence left undeveloped (Gill et al. 2000). This move will be described as a multi-activity gestural coordination, where different but related projects are being expressed in the body action of the participants at the same time. It is analysed here for its collaborative feature which enables participants to negotiate and engage in the formation of a common ground. The analysis of the parallel coordinated move also raises a need to appraise the concept of floor, and it will be proposed that 'floor' needs to be conceived as consisting in three dimensions of 'self' and 'self with other' dynamics.