The Performing Brain

The primary purposes of this article are twofold: (1) to describe work done in the 1970s on the spontaneous generation of musical structures with a computer music system by using a detailed analysis of a performer's brainwaves, and (2) to speculate on extensions of these ideas. Aside from its historical interest, this work has resulted in ideas for high-level musical input structures-new ways of playing intelligent, programmable musical instruments. Furthermore, my own work in biofeedback and the arts, begun over twenty years ago, is experiencing a revival due to the fact that advances in technology now permit realization of musical concepts in performance that depend on complex, realtime analysis of electroencephalogram (EEG) signals, previously achievable only with cumbersome, non-real-time, laboratory-bound methods. Consequently, ideas that were impractical when they were proposed many years ago are now practical. It is beyond the scope of this article to include an explanation of the principles and techniques of EEG analysis on which much of the work depends. I refer the reader to a recent monograph entitled Extended Musical Interface with the Human Nervous System: Assessment and Prospectus (Rosenboom 1990). In this monograph, a great deal more information is presented concerning (1) biofeedback modeling and its history both inside and outside of the arts; (2) the varieties of bioelectromagnetic phenomena that have been explored in feedback paradigms; (3) a detailed model for classification of EEG phenomena with particular emphasis on eventrelated potentials (ERPs) and their significance to the study of the mechanisms of attention in musical experience; and (4) applications of new technology for sensing biomagnetism, such as superconducting quantum interference devices (SQUIDs), multichannel brain imaging, and other developments in hardware and software arenas. In this