Evaluating BCI for Musical Expression: Historical Approaches, Challenges and Benefits

Abstract

A recurring challenge in the use of BCI (and more generally HCI) for musical expression is in the design and conduct of appropriate evaluation strategies when considering BCI systems for music composition or performance. Assessing the value of computationally assisted creativity is challenging in most artistic domains, and the assessment of computer assisted (or entirely computer generated) music is no different. BCI provides two unique possibilities over traditional evaluation strategies: firstly, the possibility of devising evaluations which do not require conscious input from the listener (and therefore do not detract from the immersive experience of performing, creating, or listening to music), and secondly in devising neurofeedback loops to actively maneuver the creator or listener through an expressive musical experience. Music offers some unusual challenges in comparison to other artistic interfaces: for example, often it is made in ensemble, and there is evidence to suggest neurophysiological differences are evident in ensemble measurement when compared to solo performance activities, for example see (Babiloni et al. in cortex 47:1082–1090, 2011). Moreover, a central purpose of music is often to incite movement (swaying, nodding head, dancing)—both in performer and audience—and as such this also offers up challenges for BCI/HCI design. This chapter considers historical approaches as well as making proposals for borrowing solutions from the world of auditory display (also referred to as sonification) and psychoacoustic evaluation techniques, to propose a hybrid paradigm for the evaluation of expression in BCI music applications.