Composing with Graphics: Revealing the Compositional Process through Performance.

The research presented here is product of a practice-based process that primarily generates knowledge through collaboration and exchange in performance situations. This collaboration and exchange with various musicians over a period of five years that constitutes a body of practice that is here reflected upon. The paper focuses on non-instructional graphic scores and presents some insights based on performances of works by the author. We address how composition processes are revealed in graphic scores by looking at the conditions of decision making at the point of preparing a performance. We argue that three key elements are at play in the interpretation of these types of graphic scores: performance practice, mapping and musical form. By reflecting particularly on the work Cipher Series (Rebelo, 2010) we offer insights into the strategies for approaching the performance of graphic scores that go beyond symbolic codification.

(Dis‑)Harmony in movement: effects of musical dissonance on movement timing and form

While the origins of consonance and dissonance in terms of acoustics, psychoacoustics and physiology have been debated for centuries, their plausible effects on movement synchronization have largely been ignored. The present study aims to address this by investigating whether, and if so how, consonant/dissonant pitch intervals affect the spatiotemporal properties of regular reciprocal aiming movements. We compared movements synchronized either to consonant or to dissonant sounds, and showed that they were differently influenced by the degree of consonance of the sound presented. Interestingly, the difference was present after the sound stimulus was removed. In this case, the performance measured after consonant sound exposure was found to be more stable and accurate, with a higher percentage of information/movement coupling (tau-coupling) and a higher degree of movement circularity when compared to performance measured after the exposure to dissonant sounds. We infer that the neural resonance representing consonant tones leads to finer perception/action coupling which in turn may help explain the prevailing preference for these types of tones.

‘Med Hondo’s Sarraounia: The musical articulation of cultural transformation’

This article examines music in Med Hondo’s Sarraounia, considering how it contributes to the dramatic form of the movie while concurrently articulating narratives regarding cultural transformation through both its extrinsic (cultural) and intrinsic (formal) dimensions. Examining how the use of traditional and contemporary African music politicises diegetic space by referring us to the relationships between indigenous musical forms and their global, culturally hybrid descendents, it then demonstrates the complex manner in which the film uses the formal specificities of African and Western musical idioms to articulate a narrative regarding the cultural transformations that occur when an oral culture (Africa) encounters a literate, modernised culture (the West).

Expertise is perceived from both sound and body movement in musical performance

Music is a rich form of nonverbal communication, in which the movements that expert musicians make during performance can influence the perception of expressive and structural features of the music. Whether the actual skill of a musician is perceivable from vision of movement was examined. In Experiment 1, musicians and non-musicians rated performances by novice, intermediate and expert clarinettists from point-light animations of their movements, sound recordings, or both. Performances by clarinettists of more advanced skill level were rated significantly higher from vision of movements, although this effect was stronger when sound was also presented. In Experiment 2, movements and sound from the novice and expert clarinettists' performances were switched for half the presentations, and were matched for the rest. Ratings of novice music were significantly higher when presented with expert movements, although the opposite was not found for expert sound presented with novice movements. No perceptual effect of raters' own level of musicianship was found in either experiment. These results suggest that expertise is perceivable from vision of musicians' body movements, although perception of skill from sound is dominant. The results from Experiment 2 further indicate a cross-modal effect of vision and audition on the perception of musical expertise. © 2012 Elsevier B.V.

Inhabiting Sound: Tactile-sonic links in musical meaning

Connections can be suggested between music’s occupation of physical space, its relative ‘presence’ (using Edward Hall’s notion of proxemics), and the various senses of movement which pervade it. Movement might be seen to operate with respect to music at a variety of levels of metaphorisation – as increasingly complex chains of analogy which point back to our early physical experience of the world. But of course music is, fundamentally, action. Humans put energy into systems - external or internal to themselves - which transduce that energy into the movement of air. At the acoustic level music is, emphatically and unmetaphorically, movement. Perhaps such simple physical perceptions form one route through which we might understand and explore shared senses of meaning and their capacity for ‘transduction’ between multiple individuals. Our (developmentally) early sensory models of the world, built from encounters with its physical resistances and affordances, might be a route to understanding our more clearly encultured and abstracted ('higher' level) understandings of music.

Transposing Musical Skill: Sonification of movement as concurrent augmented feedback enhances learning in a bimanual task

Concurrent feedback provided during acquisition can enhance performance of novel tasks. The ‘guidance hypothesis’ predicts that feedback provision leads to dependence and poor performance in its absence. However, appropriately-structured feedback information provided through sound (‘sonification’) may not be subject to this effect. We test this directly using a rhythmic bimanual shape-tracing task in which participants learned to move at a 4:3 timing ratio. Sonification of movement and demonstration was compared to two other learning conditions: (1) sonification of task demonstration alone and (2) completely silent practice (control). Sonification of movement emerged as the most effective form of practice, reaching significantly lower error scores than control. Sonification of solely the demonstration, which was expected to benefit participants by perceptually unifying task requirements, did not lead to better performance than control. Good performance was maintained by participants in the sonification condition in an immediate retention test without feedback, indicating that the use of this feedback can overcome the guidance effect. On a 24-hour retention test, performance had declined and was equal between groups. We argue that this and similar findings in the feedback literature are best explained by an ecological approach to motor skill learning which places available perceptual information at the highest level of importance.

An Enactive Approach to the Design of New Tangible Musical Instruments

In this paper, we propose a theoretical framework for the design of tangible interfaces for musical expression. The main insight for the proposed approach is the importance and utility of familiar sensorimotor experiences for the creation of engaging and playable new musical instruments. In particular, we suggest exploiting the commonalities between different natural interactions by varying the auditory response or tactile details of the instrument within certain limits. Using this principle, devices for classes of sounds such as coarse grain collision interactions or friction interactions can be designed. The designs we propose retain the familiar tactile aspect of the interaction so that the performer can take advantage of tacit knowledge gained through experiences with such phenomena in the real world.

DFT and in situ EXAFS investigation of gold/ceria-zirconia low-temperature water gas shift catalysts: Identification of the nature of the active form of gold

A combined experimental and theoretical investigation of the nature of the active form of gold in oxide-supported gold catalysts for the water gas shift reaction has been performed. In situ extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) experiments have shown that in the fresh catalysts the gold is in the form of highly dispersed gold ions. However, under water gas shift reaction conditions, even at temperatures as low as 100 degrees C, the evidence from EXAFS and XANES is only 14 consistent with rapid, and essentially complete, reduction of the gold to form metallic clusters containing about 50 atoms. The presence of Au-Ce distances in the EXAFS spectra, and the fact that about 15% of the gold atoms can be reoxidized after exposure to air at 150 degrees C, is indicative of a close interaction between a fraction (ca. 15%) of the gold atoms and the oxide support. Density functional theory (DFT) calculations are entirely consistent with this model and suggest that an important aspect of the active and stable form of gold under water gas shift reaction conditions is the location of a partially oxidized gold (Audelta+) species at a cerium cation vacancy in the surface of the oxide support. It is found that even with a low loading gold catalysts (0.2%) the fraction of ionic gold under water gas shift conditions is below the limit of detection by XANES (<5%). It is concluded that under water gas shift reaction conditions the active form of gold comprises small metallic gold clusters in intimate contact with the oxide support.