The Effect of Visual Field Occlusion on Visually Induced Motion Sickness

Visually induced motion sickness (VIMS), characterized by symptoms such as dizziness, nausea, and postural instability, presents significant challenges in modern visual and interactive technologies. These symptoms undermine the immersion into and comfort of virtual and augmented reality (VR/AR) systems and reduce the usability of autonomous vehicles, highlighting the urgent need to address VIMS for broader adoption of these technologies. While previous studies have largely focused on the motion characteristics that induce VIMS, the impact of visual field configuration, such as segmentation and occlusion, has been largely unexplored. To bridge this gap, we conducted five human psychophysics experiments systematically investigating how visual field segmentation and masking influence VIMS under controlled three-dimensional optical flow conditions. Participants were exposed to different masking patterns, including variations in the number of divided sections, the masking of the central screen region, and the thickness of the masks. Paired-comparison methods were employed to assess participants susceptibility to VIMS under each condition. Our findings showed that visual field segmentation significantly influenced VIMS susceptibility. Specifically, the results revealed three key findings: (1) segmenting the visual field into multiple subsections using visual masks significantly increased VIMS susceptibility, (2) thinner masks exacerbated motion sickness more than thicker ones, and (3) masking the central region of the screen reduced susceptibility. These effects were independent of the presented motion patterns. Our findings offer new insights for optimizing the design of VR/AR systems, graphical user interfaces, and autonomous vehicles by highlighting the importance of visual field configuration in mitigating VIMS for improving user experience.