Presence in virtual environments Five Theses on the Book Problem: Presence in Books, Film and VR

Presence is usually defined as the subjective sense of being and acting in a virtual environment (Slater, Usoh, & Steed, 1994). It has been shown that presence depends on certain features of the virtual environment, for instance which interactions are possible, and which interaction techniques are used (Regenbrecht & Schubert, 2002). A common assumption in research on the sense of presence is that the better the technical immersion of the user in terms of sensory fidelity, real time, field of view and picture quality, the higher the experienced presence. In short, the experienced sense of presence is seen as a function of the quality of immersion. Comparisons of different VR systems have confirmed this hypothesis (e.g., Witmer & Singer, 1998). However, from this perspective, it always seemed paradoxical that people can also experience presence in narratives presented in books, that is, with a seemingly very low immersion. For this paradox, Biocca (2002) has coined the term “the book problem. ” We think that an analyses of the book problem can be very informative for a theory of presence, and in this theoretical paper we want to present what we think are lessons of the book problem. Before we start, we have to make an assumption that helps us with this analysis: The sense of presence is not a direct function of immersion, but mediated by cognitive representations that are constructed on the basis of immersive stimuli, or, as Slater et al. (1994, p. 132) wrote: "perceptions generated by the [immersive virtual environment] are mediated through the mental models and representation systems that structure participants ' subjective experience. " In other words: Immersion is only the source of stimuli from which the users creates a mental model of the virtual environment and his relation to it. The structure of this mental model determines whether the user experiences a sense of presence or not. Presence in film and text Our analysis is based on the fact that the phenomenon of presence has also been researched in other domains, alas with different labels: In film theory, it is known as the diegetic effect (Burch, 1979; Tan