Abstract
The concept of Interaction Locus (IL) has been introduced to help the users to orient, navigate, and identify relevant interaction areas in 3D Virtual Environments (VEs). The IL is a multimodal concept: it adds to the 3D visual scene parallel information channels that are perceived by other senses. In particular, the IL emphasizes the role of music as a navigation aid in a VE. This paper reports three user-evaluations of different IL enriched virtual worlds, and in particular of the role of the IL auditory component. Results suggest that audio in 3D plays not only an aesthetic role, which the users greatly appreciate, but also a functional role simplifying navigation and helping the users to recognise scenes in the environment. Such a functional role however is subordinated to a proper understanding of the link between music and virtual space. While these experiments refer to desktop virtual reality environments, their findings are general enough to inform the design of navigational tools for other segments of the mixed reality domain.