The influence of visual representation factors on bio signals and its relation to Presence in Virtual Reality Environments

We investigated visual representation factors influencing presence in virtual reality (VR) environments. The study consists of a VR experiment displaying four scenarios differing in style and lighting and corresponding questionnaires. In order to be able to make a valid conclusion about the presence in a VR environment objective and subjective responses of ten participants concerning their VR experience is performed with several questionnaires and bio signal recordings. Concretely we used the Igroup Presence Questionnaire (IPQ), the System Usability Scale (SUS) and the NASA TLX to measure presence, subjective assessment of usability and mental workload, respectively. To obtain more objective data of presence we additionally recorded the electrocardiogram (ECG) of the eight volunteers while interacting with the VR environment. Heart rate (HR) and heart rate variability (HRV) have been analyzed and correlated to the degree of the user’s presence. The user’s task was to search for four particular objects within each room, which are displayed near the entrance point. A game was implemented to encourage the participant to interact with the VR environment. We found strong inter-individual differences in heart rate (HR) and heart rate variability (HRV) indicating an influence of visual representation factors during presence. Furthermore, the results of the IPQ showed that the realistic dark version of the room has the highest value of the “Sense of Being There”, followed by the realistic light and the stylized dark room. No differences in the systems usability scores and mental workload scores are observed.