Effects of non-diegetic information on presence : A content manipulation experiment

The role of VE content in the presence experience is controversial. Although a strong theoretical argument has been made that presence depends on the form of information presented and not the content, several relational studies have shown that content is strongly associated to presence. This paper presents an experiment which manipulated nondiegetic music played during exposure to a strongly themed VE into three conditions: Music related to the VE theme, music unrelated to the VE theme, and a baseline with no music. The results (using the ITC-SOPI as measure of presence) show that non-diegetic music affects how natural the subjects experience the VE as being, but not spatial presence. A surprising result was the predictive power of emotion (as measured by the Izard DES-II) on all presence factors. The implications of the findings to presence theory in general, and to a cognitive expectation based view of presence in particular, are discussed. Keywords--Presence, Content, Cognition, Nondiegetic, Music, Theory.