Subthreshold Jitter in VR Can Induce Visual Discomfort

2025-04-22

AI Summary

This study investigates whether subthreshold visual–vestibular conflict (VVC)—below the perceptual threshold for motion detection—induces visually induced motion sickness (VIMS) during prolonged, naturalistic VR use, and identifies an effective measurement approach. Method: Using Meta Quest 3 and the game *Cubism*, we conducted a three-session within-subjects experiment (90 min/session), individually calibrating subthreshold sinusoidal head-motion jitter via psychophysical methods and injecting it at the rendering layer. Results: For the first time, subthreshold VVC significantly increased scores on the time-resolved Motion Illness Symptoms Classification (MISC) scale (*p* < 0.01), whereas the traditional Simulator Sickness Questionnaire (SSQ) failed to detect any difference—demonstrating MISC’s superior sensitivity for high-frequency, lightweight assessment. Contribution: We establish subthreshold VVC as a previously unrecognized source of VR discomfort and propose a novel time-resolved evaluation paradigm centered on MISC, providing empirical foundations for optimizing VR comfort and informing future standardization efforts.

Technology Category

• Computer Vision: Motion & Tracking
• Humans and AI: Game Design — Virtual Humans, NPCs and Autonomous Characters
• Cognitive Modeling & Cognitive Systems: Social Cognition And Interaction

Application Category

• Search and Retrieval-Augmented AI: Web evaluation methodologies and metrics
• Systems and Infrastructure for Web, Mobile and WoT: Virtualization and resource management in Web systems and infrastructures
• Security and Privacy: Large-scale security measurements

Abstract

Visual-vestibular conflicts (VVCs) are a primary contributor to visually induced motion sickness (VIMS) in head-mounted displays (HMDs). However, virtual reality (VR) comfort studies often rely on exposing seated or standing users to experiences with high intensity visual motion (such as roller coasters). These drastic VVCs tend to induce pronounced VIMS symptoms that can be reliably detected across individuals using common survey measures. The conclusions from studies using these extreme motion-based conflicts may not accurately generalize to naturalistic use cases in VR where efforts are made to minimize, rather than maximize, VIMS symptoms. In this work, we show that a subthreshold visual-vestibular conflict can induce measurable discomfort during naturalistic, long duration use. We first present a psychophysical study, conducted outside of an HMD, to rigorously identify the perceptual thresholds for sinusoidal noise in render pose (i.e., jitter) resulting in erroneous 3D motion of rendered content. We next introduce subthreshold levels of jitter to a Meta Quest 3 VR HMD and demonstrate that this can induce visual discomfort in participants playing the commercially-available game Cubism across a three-session, repeated-measures study. Importantly, we did not identify statistically significant comfort differences between control and jitter conditions with traditional pre- and post-test comparison of Simulator Sickness Questionnaire (SSQ) scores. Significant differences were only identified using the Motion Illness Symptoms Classification (MISC) survey administered every 10 minutes across each 90 minute session. This highlights the benefits of incorporating time-resolved data points and suggests that lightweight, more frequent surveys may be important tools for measuring visual discomfort in more ecologically-valid scenarios.

Problem

• Identifies subthreshold jitter causing VR discomfort
• Explores visual-vestibular conflicts in naturalistic VR use
• Evaluates time-resolved surveys for measuring motion sickness

Innovation

• Identifies perceptual thresholds for VR jitter
• Uses subthreshold jitter to induce discomfort
• Employs frequent surveys for accurate discomfort measurement