Breaks in Presence in Virtual Environments: An Analysis of Blood Flow Velocity Responses

Abstract

One of the techniques used to monitor variations in presence during a virtual reality experience is the analysis of breaks in presence (BIPs). Previous studies have monitored peripheral physiological responses during BIPs in order to find a characteristic physiological response. In this work, blood flow velocity (BFV) in middle cerebral arteries (MCAs) has been monitored using transcranial Doppler ultrasound during the exposure to a virtual environment. Two BIPs of different intensity were forced during the virtual reality experience. Variations in BFV during each BIP and during the recovery periods that followed them have been analyzed. A decreasing trend was observed in BFV signal during the most intense BIP in most subjects. However, during the less intense BIP an oscillating behavior was observed. Significant differences have been found between the maximum percentage variations observed in each BIP. During the recovery periods, an increasing trend was observed. The mean response times (time elapsed since the beginning of the period until the maximum percentage variation in the period occured) ranged between 10.116 s and 12.774 s during the BIPs, and between 11.025 s and 13.345 during the recovery periods, depending on the vessel and on the kind of BIP.

Wired to Exit: Exploring the Effects of Wayfinding Affordances in Underground Facilities Using Virtual Reality

“…While this approach lacks the granularity of other beat-to-beat measurements, it is still possible to exploit PPG trend, amplitude and variability, and in conjunction with external stimuli, isolate the impact of potential stress events. Past research in VR games and systems has demonstrated that VR content can induce blood flow velocity and affect PPG amplitude (Rey et al, 2011). Consequently, data from the PPG sensor enables us to explore the role of the signage system as physiological stressor under extreme conditions.…”

Untitled

“…Ideally, questionnaires are replaced by objective physiological measures e.g. to quantify the subjective sense of presence by assessing the physiological response to "breaks in presence" (Rey, Parkhutik, Tembl, & Alcañiz, 2011). Indeed, several studies have been able to establish a link between physiological measures, and aspects of flow e.g.…”

Ways to Measure Spatial Presence: Review and Future Directions

“…It was found that the variations were larger in more immersive experimental conditions. Rey et al ( 2011 ) have also studied mean BFV responses during breaks in presence in a virtual environment and, for example, found a signifi cant difference among the maximum percentage BFV variations induced by breaks of different intensity.…”