Orchestral Sonification of Brain Signals and Its Application to Brain-computer Interfaces and Performing Arts

Electrical brain signals (Electroencephalogram, EEG) as well as other physiological measures can be sonified with a device called POSER, a module of the brain-computer interface ‘Thought Translation Device’ (TTD). Orchestral sonification allows for presentation of several EEG components simultaneously in real-time, referred to as ‘brainmusic’. Here, a number of applications are discussed which were realized. The results of a pilot study are presented in which 12 participants should regulate their mu-rhythm by imagination of hand movements supported by stereo feedback of the mu-rhythm. In the first session already 7/12 participants achieved significant control. As a basis for developing applications of ‘brainmusic’, the properties of different spectral components of the EEG are explained and appropriate sonification methods are described. Using ‘brainmusic’ for a live interaction with brain signals in terms of moving into the music of one’s own brain requires a detailed analysis of possible artefacts in order to understand the limitation of such an approach. The role of movement artefacts and the problem of discriminating the origins of parameters responsible for a certain sound are critically discussed to give a picture of what can be expressed in a modern dance performance demonstrating an interaction with sonified physiological signals. Finally, some examples for using ‘brainmusic’ in performing arts are presented, namely a lecture performance, braindance, and a brain meditation concert.