Auditory Scene Analysis: The Perceptual Organization of Sound by Albert Bregman (review)

REVIEWS I. Books ART /IFICIAL INTELLIGENCE: A SHORT BIBLIOGRAPHY ON AI AND THE ARTS by Richard K Zach, Gerhard Widmer, and Robert Trappl. Austrian Research Institute for Artificial Intelligence , Vienna, Austria. Reviewed byRoger B. Dannenberg, School of Computer Science, Carnegie Mellon University , Pittsburgh, PA 15123, U.S.A. The title of this technical report says almost everything: this is indeed "a short bibliography on AI and the arts". It is presented in four sections: General Arguments, Proposals, and Approaches (31 references); Artificial Intelligence in Music (124 references ); Artificial Intelligence in Literature and the Performing Arts (13 references), and Artificial Intelligence and Visual Art (57 references). About a quarter of these have short abstracts. Creating a bibliography can be a monumental task, and this bibliography should be viewed as a good and useful start, though it is by no means complete. For comparison, consider the 4,585-entry bibliography Computer Applications in Music by Deta Davis (A-REditions). No direct comparison is intended (or possible), but my point is that many more papers are likely to exist. As a rough check, I looked for several pre-1990 AI and Music articles and books (including my own, of course) in the bibliography. Out of five papers from well-known sources, only one was listed. On the other hand, I discovered a number of papers in this report that were unknown to me, so I am grateful to have a new source of references. In their introduction, the authors acknowledge the need for more references and even offer.a cup of coffee in reward for each new one. I will be sending a number of contributions, so the next time anyone is in Vienna, the coffee is on me. I hope the authors will continue to collect abstracts and publish an updated report in the future. AUDITORY SCENE ANALYSIS: THE PERCEPTUAL ORGANIZATION OF SOUND ByAlbert Bregman. A Bradford Book, MIT Press;Cambridge, MA, and London , 1990. 736 pp. Trade, $55.00. Reviewed by Gregory Kramer, CLARITY, SantaFeInstitute, Nelson Lane, Garrison, NY 10524, U.S.A. As artists working with sound we are, whether we know it or not, constantly addressing questions of auditory perception . Such musical considerations as "If this orchestral part or tape track is too active here, it will distract from this other, more subtle, section which 'isco-occurring" are also considerations of how the auditory events we are formulating are perceived. Attentional elements, masking (one sound obscuring another) and, more generally , auditory streaming, are all dealt with in Albert Bregman's book, Auditory Scene Analysis. The research presented in Auditory Scene Analysisdescribes the process of grouping auditory events into separate streams and the techniques we use to do this. Streaming is commonly illustrated by the cocktail-party effect. Ifwe are in a room full of people talking, how do we follow the voice of the person with whom we are speaking, even if some other voices are louder? In Bregman's words, "The problem of scene analysis is this: Although we need to build separate mental descriptions of the different sound-producing events in our environments , the pattern of acoustic energy that is received by our ears is a mixture of the effects of the different events." AuditoryScene Analysisshows how the auditory scene follows the essential Gestalt principles that were demonstrated 60 years ago for vision, thus generalizing these phenomena of the mind and underlining their validity. Bregman demonstrates, for example, that, as in vision, it is impossible to perceive auditory elements without their forming an organized whole within a perceptual 'field'. Basically, elements will be clustered as 'events' in our perceptual experience. These events he calls 'auditory streams'. As a case in point: given "two different instruments playing different but interwoven parts; listeners will find it impossible to focus their attention on both streams at the same time". Here is the underlying foundation of 'figure / ground'. The exclusive allocation principle (referred to by Gestaltists for vision) says that a sensory element should not be used in more than one description at a time. Back in the 1930s the Gestalt psychologists Kohler, Kafka and Wertheimer caused a revolution in psychology by demonstrating that perception is not made ofisolated elements, but...