E FFECTS OF P OLYPHONIC C ONTEXT,I NSTRUMENTATION , AND M ETRICAL L OCATION ON S YNCOPATION IN M USIC MARIA A. G. WITEK ,E RIC F. C LARKE & MORTEN L. K RINGELBACH University of Oxford, Oxford, United Kingdom P ETER V UUST Aarhus University Hospital & The Royal Academy of Music, Aarhus/Aalborg, Denmark IN MUSIC, THE RHYTHMS OF DIFFERENT INSTRUMENTS are often syncopated against each other to create ten- sion. Existing perceptual theories of syncopation cannot adequately model such kinds of syncopation since they assume monophony. This study investigates the effects of polyphonic context, instrumentation and metrical location on the salience of syncopations. Musicians and nonmusicians were asked to tap along to rhythmic pat- terns of a drum kit and rate their stability; in these patterns, syncopations occurred among different num- bers of streams, with different instrumentation and at different metrical locations. The results revealed that the stability of syncopations depends on all these factors and music training, in variously interacting ways. It is pro- posed that listeners’ experiences of syncopations are shaped by polyphonic and instrumental configuration, metrical structure, and individual music training, and a number of possible mechanisms are considered, includ- ing the rhythms’ acoustic properties, ecological associa- tions, statistical learning, and timbral differentiation. Received: August 7, 2013, accepted April 5, 2014. Key words: syncopation, rhythm, meter, polyphony, instrumentation D ESPITE WIDESPREAD ADVANCES IN UNDER- standing the cognitive mechanisms that under- pin music perception, rhythm perception remains a field in which there are significant theoretical and empirical lacunae. Particular challenges lie in the definitions of the separate but closely related attributes of meter, rhythmic complexity, and syncopation. Since the 1970s there have been a number of attempts to define meter, using a variety of theoretical and empirical approaches (e.g., Clarke, 1999; Jones, 2009; Large & Snyder, 2009; Lerdahl & Jackendoff, 1983; Martin, 1972; Parncutt, 1994; Povel & Essens, 1985). In formal terms, meter is generally referred to as the alternation of strong and weak accents, which provides the framework for a rhythmic pattern, and is partially expressed in the time signature of a piece of music. However, there is more disagreement about the perceptual definition of meter. At the most basic level, meter perception is understood as a subjective sense of pulse, with the main pulse, to which sensorimotor synchronization is com- monly directed, referred to as the tactus. However, the hierarchical differentiation of pulses above and below the tactus and the structure and perceptual reality of this hierarchy still remain unclear. These uncertainties are reflected in the definition of meter provided by Jones (2009) in the Oxford Handbook of Music Psychology: ‘‘Intuitively, meter perception refers to a listener’s sen- sitivity to musical timing regularities, evident when ‘keeping time’ by tapping in synchrony with musical tones. Sometimes tones are clearly accented and con- tribute to metric hierarchies ( ... )’’ (p. 81, italics in orig- inal). The strengths of this definition lie in its recognition of the role of sensorimotor systems in per- ception and the implementation of hierarchy as an option and not a prerequisite, which accommodates different theoretical views of the structure of metrical hierarchies, but leaves room for less hierarchical under- standings of meter that might characterize the musics of some non-Western cultures. By comparison, Lerdahl and Jackendoff present a more strictly hierarchical view of meter in their Generative Theory of Tonal Music (1983), as have a number of other authors (e.g., Longuet-Higgins & Lee, 1984; Temperley, 2007, 2009, 2010). Lerdahl and Jackendoff propose that rhythm per- ception is underpinned by a framework of metrical salience organized in a tree-like structure, where every beat is recursively subdivided into equally spaced beats at the next level. This hierarchical structure is derived from the musical input on the basis of bottom-up pro- cesses that interact with a small number of top-down cognitive rules. Another increasingly influential model, which pays considerably more attention to the body, is dynamic Music Perception, VOLUME 32, ISSUE 2, PP. 201–217, ISSN 0730-7829, ELECTRONIC ISSN 1533-8312.  2014 BY THE REGENTS OF THE UNIVERSITY OF CALIFORNIA ALL RIGHTS RESERVED. PLEASE DIRECT ALL REQUESTS FOR PERMISSION TO PHOTOCOPY OR REPRODUCE ARTICLE CONTENT THROUGH THE UNIVERSITY OF CALIFORNIA PRESS ’ S RIGHTS AND PERMISSIONS WEBSITE, HTTP:// WWW. UCPRESSJOURNALS . COM/ REPRINTINFO. ASP. DOI: 10.1525/ MP.2014.32.2.201 Polyphonic Context and Instrumentation in Syncopation 201