The Influence of Avatar Embodiment on Time Perception - Towards VR for Time-Based Therapy

Abstract

Psycho-pathological conditions, such as depression or schizophrenia, are often accompanied by a distorted perception of time. People suffering from this conditions often report that the passage of time slows down considerably and that they are “stuck in time.” Virtual Reality (VR) could potentially help to diagnose and maybe treat such mental conditions. However, the conditions in which a VR simulation could correctly diagnose a time perception deviation are still unknown. In this paper, we present an experiment investigating the difference in time experience with and without a virtual body in VR, also known as avatar. The process of substituting a person’s body with a virtual body is called avatar embodiment. Numerous studies demonstrated interesting perceptual, emotional, behavioral, and psychological effects caused by avatar embodiment. However, the relations between time perception and avatar embodiment are still unclear. Whether or not the presence or absence of an avatar is already influencing time perception is still open to question. Therefore, we conducted a between-subjects design with and without avatar embodiment as well as a real condition (avatar vs. no-avatar vs. real). A group of 105 healthy subjects had to wait for seven and a half minutes in a room without any distractors (e.g., no window, magazine, people, decoration) or time indicators (e.g., clocks, sunlight). The virtual environment replicates the real physical environment. Participants were unaware that they will be asked to estimate their waiting time duration as well as describing their experience of the passage of time at a later stage. Our main finding shows that the presence of an avatar is leading to a significantly faster perceived passage of time. It seems to be promising to integrate avatar embodiment in future VR time-based therapy applications as they potentially could modulate a user’s perception of the passage of time. We also found no significant difference in time perception between the real and the VR conditions (avatar, no-avatar), but further research is needed to better understand this outcome.

Body and Time: Virtual Embodiment and its Effect on Time Perception

“…However the study was limited in terms of immersion and the implementation of the virtual embodiment. Unruh et al [68] countered many of these limitations by using an HMD, replicating a real environment in VR, giving subjects a human avatar and measuring virtual embodiment using a questionnaire tailored and validated specifically for virtual embodiment. Unlike Zopf et al [90], they did not investigate an active scenario, but simply had subjects wait in VR and showed that the manipulation of virtual embodiment impacts time perception in a waiting room scenario.…”

“…All time perception items as well as our additional embodiment item, the VRSQ, the IPQ and the VEQ ratings were analyzed on the interval measurement scale [5,29,48,68].…”

“…Since there were only 15 participants per condition and important measures such as presence and embodiment were not obtained, it is difficult to draw firm conclusions. A study by Unruh et al [68] replicated the approach from Lugrin et al [42] and focused on collecting a larger sample and obtaining presence and embodiment data. The results show that time was passing faster in the avatar condition compared to the no avatar condition in VR.…”

“…We refer to this as the "time interval estimation". Duration of time, passage of time and boredom were assessed with the same questions and scales previously used by Lugrin et al [42] and Unruh et al [68], a) "Intuitively (without further thinking), how long do you think the waiting time lasted (in minutes and seconds)? ", b) "How fast did time pass for you?"…”

“…First evidence show that time passes faster when waiting in VR with a virtual body than without a body, but no difference was found in comparison to real world waiting [68]. However, waiting is a very specific scenario when it comes to time perception [69] and in many VR applications users are more active and frequently interact with the environment (e.g.…”