Snapshots of complexity: using motion capture and principal component analysis to reconceptualise dance

This article brings together the disparate worlds of dance practice, motion capture and statistical analysis. Digital technologies such as motion capture offer dance artists new processes for recording and studying dance movement. Statistical analysis of these data can reveal hidden patterns in movement in ways that are semantically ‘blind’, and are hence able to challenge accepted culturo-physical ‘grammars’ of dance creation. The potential benefit to dance artists is to open up new ways of understanding choreographic movement. However, quantitative analysis does not allow for the uncertainty inherent in emergent, artistic practices such as dance. This article uses motion capture and principal component analysis (PCA), a common statistical technique in human movement recognition studies, to examine contemporary dance movement, and explores how this analysis might be interpreted in an artistic context to generate a new way of looking at the nature and role of movement patterning in dance creation.

Online motor control in children with developmental coordination disorder: chronometric analysis of double-step reaching performance

Background
Although there are a number of plausible accounts to explain movement clumsiness in children [or developmental coordination disorder (DCD)], the cause(s) of the disorder remain(s) an issue of debate. One aspect of motor control that is particularly important to the fluid expression of skill is rapid online control (ROC). Data on DCD have been conflicting. While some recent work using double-step reaching suggests no difficulty in online control, others suggest deficits (e.g. based on sequential pointing). To help resolve this debate, we suggest two things: use of recent neuro-computational models as a framework for investigating motor control in DCD, and more rigorous investigation of double-step reaching. Our working assumption here is that ROC is only viable through the seamless integration of predictive (or forward) models of movement and feedback-based mechanisms.

Aim
The aim of this chronometric study was to explore ROC in children with DCD using a double-step reaching paradigm. We predicted slower online adjustments in DCD based on the argument that these children manifest a core difficulty in predictive control.

Methods
Participants were a group of 17 children with DCD and 27 typically developing children aged between 7 and 12 years. Visual targets were presented on a 17-inch LCD touch screen, inclined to an angle of 15° from horizontal. The children were instructed to press each target as it appeared as quickly and accurately as possible. For 80% of the trials, the central target location remained unchanged for the duration of the movement (non-jump trials), while for the remaining 20% of trials, the target jumped at movement onset to one of the two peripheral locations (jump trials). Reaction time (RT), movement time (MT) and reaching errors were recorded.

Results
For both groups, RT did not vary according to trial condition, while children with DCD were slower to initiate movement. Further, the MT of children with DCD was prolonged to a far greater extent on jump trials relative to controls, with a large effect size. As well, children with DCD committed significantly more errors, notably a reduced ability to inhibit central responses on jump trials.

Conclusion
Our findings help reconcile some disparate findings in the literature using similar tasks. The pattern of performance in children with DCD suggests impairment in the ability to make rapid online adjustments that are based on a predictive (or internal) model of the action. These results pave the way for future kinematic investigation.

Does implicit motor imagery ability predict reaching correction efficiency? A test of recent models of human motor control

Neurocomputational models of reaching indicate that efficient purposive correction of movement midflight (e.g., online control) depends on one's ability to generate and monitor an accurate internal (neural) movement representation. In the first study to test this empirically, the authors investigated the relationship between healthy young adults’ implicit motor imagery performance and their capacity to correct their reaching trajectory. As expected, after controlling for general reaching speed, hierarchical regression demonstrated that imagery ability was a significant predictor of hand correction speed; that is, faster and more accurate imagery performance associated with faster corrections to reaching following target displacement at movement onset. They argue that these findings provide preliminary support for the view that a link exists between an individual's ability to represent movement mentally and correct movement online efficiently.

Activity patterns of free-ranging koalas (Phascolarctos cinereus) revealed by accelerometry

An understanding of koala activity patterns is important for measuring the behavioral response of this species to environmental change, but to date has been limited by the logistical challenges of traditional field methodologies. We addressed this knowledge gap by using tri-axial accelerometer data loggers attached to VHF radio collars to examine activity patterns of adult male and female koalas in a high-density population at Cape Otway, Victoria, Australia. Data were obtained from 27 adult koalas over two 7-d periods during the breeding season: 12 in the early-breeding season in November 2010, and 15 in the late-breeding season in January 2011. Multiple 15 minute observation blocks on each animal were used for validation of activity patterns determined from the accelerometer data loggers. Accelerometry was effective in distinguishing between inactive (sleeping, resting) and active (grooming, feeding and moving) behaviors. Koalas were more active during the early-breeding season with a higher index of movement (overall dynamic body acceleration [ODBA]) for both males and females. Koalas showed a distinct temporal pattern of behavior, with most activity occurring from mid-afternoon to early morning. Accelerometry has potential for examining fine-scale behavior of a wide range of arboreal and terrestrial species.

The elimination race in track cycling : patterns and predictors of performance

The track cycling Omnium is a multi-event competition that has recently been expanded to include the Elimination Race (ER), which presents a unique set of physical and tactical demands. The purpose of this research was to characterise the performance attributes of successful and unsuccessful cyclists in the ER, that are also predictive of performance. Video recordings of four international level ERs were analysed. The performance attributes measured related to the cyclists’ velocity and two dimensional position in the peloton. The average velocity of the peloton up to lap 30 (of 50) was relatively high and consistent (52.2±1.5 km/h). After lap 30, there was a significant (p<0.001) change in velocity (49.9±2.4 km/h), characterised by more fluctuations in lap-to-lap velocity. Successful ER cyclists adopted a tactic of remaining in the middle of the peloton, in the lower lanes of the velodrome, thus avoiding the risk of elimination at the rear and the extra effort required to remain on the front of the peloton. Unsuccessful cyclists tended to reside in the rear and upper (higher) portions of the peloton, risking elimination more often and having to ride faster than those in the lower lanes of the velodrome. The physiological demands of the Elimination Race that are determined by velocity, vary throughout the Elimination Race and the pattern of movement within the peloton is different for successful and unsuccessful cyclists. The findings of the present study may confirm some aspects of race tactics that are currently thought to be optimal, but they also reveal novel information that is useful to coaches and cyclists who compete in the Elimination Race.

Spawning season movements of Macquarie perch (Macquaria australasica) in the Yarra River, Victoria

The Macquarie perch (Macquaria australasica) is a threatened fish species that inhabits rivers and impoundments in south-eastern Australia. Previous studies have shown that Macquarie perch in impoundments exhibit synchronised upstream spawning migrations to shallow, fast-flowing habitats in the lower reaches of inflowing streams. There has been little study of movement behaviours of entirely riverine populations of Macquarie perch despite this being the species’ natural habitat. Here, radio-telemetry is used to test the hypothesis that riverine populations exhibit synchronised migrations during the spawning season. Thirty Macquarie perch in the Yarra River, Victoria, a translocated population outside of the species’ natural range, were radio-tagged before the late spring–early summer spawning season and their movements followed over a 10-month period (May 2011 to February 2012). Tagged fish typically occupied restricted reaches of stream (<450 m). Sixteen of the fish undertook occasional upstream or downstream movements (~250–1000 m) away from their usual locations, particularly associated with large flow variations during the spawning season. There was no evidence of synchronised migratory behaviour or movement of multiple fish to specific locations or habitats during the spawning season. Whilst further research over more years is needed to comprehensively document the spawning-related behaviours of riverine Macquarie perch, our study demonstrates that management of riverine populations of this threatened species cannot necessarily be based on the model of spawning behaviour developed for lacustrine populations.

‘Interest’ in Kierkegaard’s structure of consciousness

Kierkegaard’s identification of “consciousness” with “interest” (interesse) in his unfinished work Johannes Climacus adds a distinctive dimension to his phenomenology of subjectivity. Commentators, however, have largely identified interesse with lidenskab (“passion”), a conflation I argue to be mistaken, or have otherwise failed to note the structural implications of interesse for Kierkegaard’s account of cognition. I draw out these implications and argue that the Climacan account of interest as the experience of finding ourselves in-between ideality and reality implies, in the context of Kierkegaard’s trichotomous ontology of consciousness, a form of non-thetic self-referentiality built into cognition itself. This self-referentiality also has the intriguing implication of making consciousness itself inherently teleological.

Teaching a digital performing agent: artificial neural network and hidden Markov Model for recognising and performing dance movement

For a Digital Performing Agent to be able to perform live with a human dancer, it would be useful for the agent to be able to contextualize the movement the dancer is performing and to have a suitable movement vocabulary with which to contribute to the performance. In this paper we will discuss our research into the use of Artificial Neural Networks (ANN) as a means of allowing a software agent to learn a shared vocabulary of movement from a dancer. The agent is able to use the learnt movements to form an internal representation of what the dancer is performing, allowing it to follow the dancer, generate movement sequences based on the dancer's current movement and dance independently of the dancer using a shared movement vocabulary. By combining the ANN with a Hidden Markov Model (HMM) the agent is able to recognize short full body movement phrases and respond when the dancer performs these phrases. We consider the relationship between the dancer and agent as a means of supporting the agent's learning and performance, rather than developing the agent's capability in a self-contained fashion.

The new wilderness: A practice-led model for arts based enquiry

The New Wilderness is a practice-led, multidisciplinary arts project first piloted by artists, writers, teachers and academics from Geelong, Deakin University and Courthouse ARTS Centre in 2013. In a series of workshops run by artists, and working to specific themes, the project provided a platform for participants to explore and respond creatively to change in the community; it culminated in a large-scale installation at Courthouse ARTS Centre’s main gallery. Our paper positions the project as a able to cut across convention, empowering young artists to respond to ‘big questions’ of relevance to the changing material, spatial and social relations within their communities. In questioning and seeking to transform communities into sustainable media, economic, environmental and social ecologies, this emergent model begins with a localised focus, which is designed to travel across time and place, and pedagogical frameworks. The paper positions Geelong as a community under radical transformation in its economic foundations and demographics. As artists and academics living and working in the region we see it as an experimental ground for investigations into a series of provocations that mirror the shape of the paper we intend to give. The provocations, as outlined in the workshops, might also be envisaged as new relations to:Object – From consumable to unusable to play. In revisiting the first iteration of The New wilderness in 2013 we discuss the ‘superfictional’ (Hill, 2000) enquiry that participants were asked to engage with. Its premise described Geelong as an abandoned, post-apocalyptic site. Participants were asked to imagine themselves as a group of future explorers and excavate objects from the city’s old tip. In unearthing their choices and re-presenting the objects in the gallery the participant was prompted to analyse site, situation, object and process as phenomena for ‘being’ or ‘telling stories’, providing insights into wider realms of cultural experience (Ellis, Adams and Bochner, 2010). Parallel to this ‘autoethnographic’ reflection our paper uses the philosopher Giorgio Agamben’s analysis of consumer and material culture. He traces the subject’s relation to objects from use-value, to exchange-value and in the era of extreme capitalism, to pure exhibition-value. He searches for ways that the objects produced in our material culture can be ‘profaned’ (Agamben, 2007). Space – From the material to the spatial to the situation. We are interested in how objects and the practices they elicit can be ‘profaned’ by their situation (Agamben, 2007; Wark, 2103). To profane, according to Agamben, is to open up the possibility that the object loses its exhibition-value to ‘a special form of negligence’ (Agamben). He uses the example of the child’s ability to insinuate any object into a new logic of play (Agamben). Like the objects excavated for The New Wilderness they could be from a variety of spheres – business, household, industry, health etc… The child, like the artist, reconstitutes, reorders and assembles new relations between things. In reflecting on the first New Wilderness project the paper correlates the creative response of the participant (student, child, artist) with the occupier. The Occupy Movement, which took up residence in many of the world’s cities’ financial districts in 2011, used a number of strategies commensurate with both Agamben’s notion of profanation and McKenzie Wark’s reading of the Situationist International’s use of détournement - as a strategy that releases objects and subjects back into the field of play (Wark, 2013). The field was taken by the occupy movement to be the space in which they occupied – capitalism, its logic and its practices, were, for a short time, redundant in the occupied field. The New Wilderness conceptualises the city as a localised field, from which its discarded objects can be ‘profaned’ or, repurposed, to reflect on shared histories, responsibilities, pedagogies and future action. Subject: self/other– As much as we propose New Wilderness to be a pedagogical initiative we see it as personal, critical and political. In the themed workshops, designed to elicit personal responses to the object and the site, which culminated in a multi-disciplinary installation, performance and/or text based work, participants were encouraged to think critically, and importantly, collectively. Through the four workshops run in the first iteration of the project participants were asked to re-consider their material value-systems, much as the occupy movement was trying to do, and like the occupiers, participants were empowered to be agents of change. Our paper reflects on the practical outcomes and the conceptual, political and pedagogical strategies embedded in The New Wilderness project. The paper affords us the additional opportunity to imagine a life for it in other geographical, socio-economic and educational situations. Merinda Kelly and Cameron Bishop, 2013Bio: Merinda Kelly is a sculptor and installation artist, educator and PhD student at Deakin University. Her research interests include Visual Culture, Practice Led Research, the Ontology of Art, and Autoethnography. Her most recent work includes the Pop Archaeology' and the Globo-Touro Projects.Bio: Dr Cameron Bishop is an artist and academic working in Visual Arts at Deakin University. He exhibits regularly and has written a number of journal articles and book chapters. His research has focused on the philosophical and postcolonial dimensions of space and subjectivity and more recently has evolved into an active interest in strategic interventions into space and practice.

Stillness and movement: a bodily approach to photography

My paper will address both Duration and temporality of the ‘still’ imageand Sensorial and bodily experience of photography through a discussion of a recent body of work ‘Fly Rhythm’, a series of photographs and video works exhibited in a gallery context.By acknowledging the inter-relationship between the body and the camera my project seeks to challenge a perceived separation between performance and photography. Fly Rhythm was conceived through a performative somatic process. Through using a custom made camera I was able to negotiate time and space to create a visual drawing of movement and stillness together in photography. The resultant images are discussed as a notation of body movement – a record of bodily history enabled through a self imposed discipline of learning to read light.I initially constructed a human size camera to understand how photography works. Spending time inside observing the way light moves and affects the formation of sight is also a way of embodying the act of photography. I responded by making a bespoke camera that enabled light to be captured during extended periods while moving. My project is dependent upon a self-imposed discipline of intuiting light’s strength and erratic changes, a skill developed by making analogue prints while inside a camera obscura. Once I had developed an ability to read light’s changes and gain an understanding of camera mechanics I made durational recordings moving through the landscape on Bruny Island Tasmania and industrial sites in Melbourne, photographs exhibited as part of Fly Rhythm. I will discuss these prints in context with the idea that light is a conduit through which past and present fuse together in a bodily act of photographing and processing images.I will explore durational aspects of photography by discussing light’s relative motion while taking photographs without using the viewfinder or composing images in the traditional way. Rather, the camera at the end of my arm is directed through how I read light therefore a choreography notated in the prints – a kind of body signatureMy practice enables a new the way of seeing, in a spontaneous hand held process creating a sense of embodiment. By analyzing process my paper will consider how the body together with analogue and 21st century digital technology coalesce cross-disciplinary practice combining visual art, performance and photographic disciplines.I also explored limitations of digital light in contrast with ‘natural’ light by a making a gamut of dissolving colour determined by the software based on two pixels. Projected into the ambient light ‘Glide’ is an 11minute durational work installed at the Substation Contemporary Art Space in Melbourne Australia.

Cameras and body memory create new blends of performance with visual art practice

I propose that a learnt somatic experience of dance can translate into another discipline such as visual art. In my visual art practice I combine both photography, which is traditionally seen as a still medium, and performance in order to create a new form of embodiment. I have developed two series of art works of prints and video made in response to the Australian landscape. By analyzing my method of movement and photography I will describe how an embodied dance language can result in a material outcome – a series of drawings of light and movement, a body signature made possible through old and new technology. I have activated a performative state while capturing images discovering new ways of using technology reliant upon my knowledge of dance, performance and photography. Making a human size camera to make analogue prints I gained an intuitive knowledge of light – a skill that has become foundational in performance and photography. In response to space and light in the Australian landscape I then built a custom made camera that allows for the longest possible time to capture an image. I move while taking the image and use the camera as if an eye at the end of my arm. In this way I activate dance skills and embodied knowledge of space, timing and light, opening up a radical space for new thinking, making and performing.Furthermore this process engages memory and sentiment embodied through age. Many artists have responded to the unique qualities of the Australian landscape and by using a performative/photographic approach I have engaged with my own body memory. Being brought up in the landscape and training in ballet my body has acquired memories at a cellular level. My method has given memory a voice. In doing these works I have become conscious of how unconscious memories of the space and light in the landscape is a movement vocabulary activated in a way that ‘feels’ like dancing. As an ageing person this experience is profound and the resultant materialisation of the photographs and videos leave a material record of the event. The sentiments evoked through my process bridge the past with the present, the body with the mind, memory with body and space connecting disciplines in a new way.The materialisation of artworks itself continues cross-disciplinary processes using a technique that is a continuum of the performative. Through using technology I release memory of the landscape and pixel by pixel build imagery that relies on and is a part of the performative process. It is a photographic performance dance manifesting as pigment on paper exhibited a gallery context. The exhibition allows a space for the viewer to respond - re-membering the universal the act of moving. The works titled ‘body signatures’ and ‘Fly Rhythm’ become a communicative device in the gallery context.My paper through an analysis of process and methods used in making the two series will talk to several of the subjects listed and reveal a new way of connecting performance and visual art and old and new technologies.

Guidelines for using movement science to inform biodiversity policy

Substantial advances have been made in our understanding of the movement of species, including processes such as dispersal and migration. This knowledge has the potential to improve decisions about biodiversity policy and management, but it can be difficult for decision makers to readily access and integrate the growing body of movement science. This is, in part, due to a lack of synthesis of information that is sufficiently contextualized for a policy audience. Here, we identify key species movement concepts, including mechanisms, types, and moderators of movement, and review their relevance to (1) national biodiversity policies and strategies, (2) reserve planning and management, (3) threatened species protection and recovery, (4) impact and risk assessments, and (5) the prioritization of restoration actions. Based on the review, and considering recent developments in movement ecology, we provide a new framework that draws links between aspects of movement knowledge that are likely the most relevant to each biodiversity policy category. Our framework also shows that there is substantial opportunity for collaboration between researchers and government decision makers in the use of movement science to promote positive biodiversity outcomes.

Accelerometer validity to measure and classify movement in team sports

 In team sports accelerometers are used to monitor the physical demands of athletic performance. Daniel's research showed that accelerometer accuracy can be improved through filtering. He also showed that the accelerometer can be used to automatically classify the type of movement performed. Further improving the understanding of team sports.

Antisubjectivism and the (spectral) return of consciousness in landscape research

This paper analyses the changing conceptions of consciousness within landscape research over a critical period from the late 20th century to the present. The 1980s and 1990s mark a radical shift in the framing of consciousness away from psychological, perceptual, or experiential perspectives towards an ontology of consciousness as signifier, cultural artifact, and ideology. In cultural geography and the visual arts, these reframings can be characterised as anti subjectivist in that they do not attempt to problematize human consciousness so much as deactivate it and disqualify it from discussion. I draw out the theoretical and critical foundations of these antisubjectivist approaches as well as the subsequent opening out of the notion of landscape in more recent discussion. This ‘opening out’ implicates a more complex reengagement with minds, bodies, and landscapes and with the contested distinctions between subject and object. At the same time however, consciousness is seldom formulated explicitly within the literature and hence consciousness often occupies a spectral presence in the landscape of landscape research. I use one of my own paintings, Dalek in Landscape, to presage the discussion and attempt to highlight the tensions between these ideological, cultural and biological dimensions of consciousness at play within the landscape idea. Given the broader adoption of these anti-subjectivist developments within the academy, the example of landscape serves as a potentially useful case study for thinking upon the changing conceptions of consciousness in cognate creative and academic disciplines.

Not so fast: swimming behavior of sailfish during predator-prey interactions using high-speed video and accelerometry

Billfishes are considered among the fastest swimmers in the oceans. Despite early estimates of extremely high speeds, more recent work showed that these predators (e.g., blue marlin) spend most of their time swimming slowly, rarely exceeding 2 m s(-1). Predator-prey interactions provide a context within which one may expect maximal speeds both by predators and prey. Beyond speed, however, an important component determining the outcome of predator-prey encounters is unsteady swimming (i.e., turning and accelerating). Although large predators are faster than their small prey, the latter show higher performance in unsteady swimming. To contrast the evading behaviors of their highly maneuverable prey, sailfish and other large aquatic predators possess morphological adaptations, such as elongated bills, which can be moved more rapidly than the whole body itself, facilitating capture of the prey. Therefore, it is an open question whether such supposedly very fast swimmers do use high-speed bursts when feeding on evasive prey, in addition to using their bill for slashing prey. Here, we measured the swimming behavior of sailfish by using high-frequency accelerometry and high-speed video observations during predator-prey interactions. These measurements allowed analyses of tail beat frequencies to estimate swimming speeds. Our results suggest that sailfish burst at speeds of about 7 m s(-1) and do not exceed swimming speeds of 10 m s(-1) during predator-prey interactions. These speeds are much lower than previous estimates. In addition, the oscillations of the bill during swimming with, and without, extension of the dorsal fin (i.e., the sail) were measured. We suggest that extension of the dorsal fin may allow sailfish to improve the control of the bill and minimize its yaw, hence preventing disturbance of the prey. Therefore, sailfish, like other large predators, may rely mainly on accuracy of movement and the use of the extensions of their bodies, rather than resorting to top speeds when hunting evasive prey.