A recurrence might be considered as an event that occurs again over short or long timescales. However, the Oxford English Dictionary definition provokes further consideration regarding what to recur means:
Recur . . . occur again periodically or repeatedly . . . (of a thought, image, or memory) come back to one’s mind . . . (recur to) go back to (something) in thought or speech [1].
Accordingly, musical recurrence can also be thought to account for sound materials that refer back to earlier related instances. These referrals might be based on different degrees of similarity, ranging from apparent sameness to vestiges of resemblance. This will of course include sound entities and their subsequent instances. However, acousmatic music creation affords the composer the means to transform recorded sound in various ways. Transformed sound material often exhibits traces of previous instances, and where this is the case pertinent connections may be made. Where certain features are seen to be the unifying elements among particular sounds, broader groupings can be established based on these common, recurrent attributes. Thus our notion of recurrent phenomena also includes returning states i.e. configurations and combinations of sounds; event types; and/or derivations produced through sound transformation processes.
The idea of recurrence in acousmatic music, as discussed by Seddon [2], deals with issues of (i) correspondence—how sounds appear to relate to one another, in terms of spectromorphological features and source bonding—and (ii) temporal relationships—the different time spans over which related sounds occur, and the impressions their recurrence makes on listening experience. As such, this approach concerns the ways in which the constituent sound identities exhibit common characteristics (i.e. how they are related, to greater or lesser degrees, in terms of common features) and how they are perceived to be related over time.
By taking a recurrence-based approach to acousmatic music, it is assumed that memory has a fundamental role in the musical experience, and that the remembered sound materials have a structural significance.
Dowling and Harwood propose that “what we remember of a piece depends greatly on what we have attended to in listening,” and continue: “our attention is guided by knowledge structures developed in our experience of the world, called schemata” [3]. Although their discussion deals with melodic schemata (including pitch, contour and intervals), more general kinds acquired through everyday experience may similarly guide and influence listening attention. Indeed, Bregman notes: “our voluntary attention employs schemas” [4], which are based on existing knowledge and experience of classes of signals, such as speech or machine noises. (‘Schemata’ and ‘schemas’ are interchangeable terms.) Accordingly, previous listening experience may significantly condition what is attended to and what is remembered within a work, influencing the recurrent phenomena perceived. Given that recurrence is a memory-driven formal mechanism, an understanding of how memory functions illuminates the processes through which remembered phenomena are brought into consciousness, and how these processes might affect the listening experience.
There are many differing approaches to the consideration and conceptualisation of memory. Tulving’s theory of episodic memory [5], is pertinent when considering recurrent phenomena. Episodic memory is “the kind of memory that is involved in remembering past events” [6], and features two main aspects: encoding and retrieval [7]. Encoding begins with perceiving an event, and ends with a memory trace (a bundle of features). When a cue is experienced the trace is retrieved, and information from both the cue and the memory trace is combined, resulting in ecphoric information. The relative contribution of the memory trace to ecphoric information correlates with the intensity of the recollective experience [8]. Significantly, memory traces can be recoded because subsequent material, similar to the original event, can change what is stored in memory about the original [9]. Thus, the memory traces of an event are not necessarily fixed, but may well become modified in response to subsequent cues.
Recurrence brings with it the problematic notion of units, which will have to be resolved in the mind of the listener. It is likely that sound entities imposed strongly on listening consciousness will be perceived as units to some extent, distinct from the surrounding musical texture. Indeed, McAdams suggests that “we remember discrete entities easier than continuous or unclearly demarcated ones, at least for the memory of structures” [10]. The apprehension of discrete sound entities is likely in contexts where the boundaries of those entities are easily discernible. However, the notion of the unit can become problematic because not all musical works can be conveniently sub-divided in such a way. Indeed it is questionable whether the attempt to segment a work into smaller constituent entities is always valid, or possible, particularly in acousmatic music. Recurrence is not solely unit-based, and significant recurrent features may be missed if an exclusively unit-based approach is adopted. Textural combinations, common spectral formations, or more 'abstract' notions, such as acceleration or fragmentation, may all recur, but such recurrences are not necessarily dependent on the perception of discrete sound units. Furthermore, recurrences of structural features over longer timescales may not be restricted to single distinguishable units. Therefore, a flexible view that accommodates both unit-based and non-unit-based phenomena is needed.
[1] "Recur", Oxford Dictionaries [Online], Oxford, Oxford University Press, 2010 [http://oxforddictionaries.com/definition/identity (10th September 2011)].
[2] SEDDON, Ambrose, "Recurrence in Acousmatic Music", Dissertation, City University, London, 2013.
[3] DOWLING, W. Jay and HARWOOD, Dane L., Music Cognition, London, Academic Press Inc. Ltd., 1986, p. 124.
[4] BREGMAN, Albert S., Auditory Scene Analysis, Cambridge, MIT Press, 2000, p. 667.
[5] TULVING, Endel, Elements of Episodic Memory, Oxford, Oxford University Press, 1983.
[6] Ibid., p. 1.
[7] TULVING, Endel, "Précis of Elements of Episodic Memory", Behavioral and Brain Sciences, vol. 7, n° 2, 1984, p. 229-231.
[8] Ibid., p. 231.
[9] Ibid., p. 230.
[10] MCADAMS, Stephen, "Psychological Constraints on Form-Bearing Dimensions in Music", Contemporary Music Review, vol. 4, n° 1, 1989, p. 184.