--- title: "The Ocular Command Center: How Eye Responses to Luminance, Color, Tunneling, and Visual Suppression Mediate Users' Physiological States in VR" authors: - Andreia Valente - Augusto Esteves - Mark Billinghurst year: 2026 venue: "Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems (CHI 2026)" doi: "10.1145/3772318.3791328" url: "https://andreia-valente.com/publications/valente2026ocular.html" pdf: "https://andreia-valente.com/pdfs/valente2026ocular.pdf" topics: - Eye Tracking - Virtual Reality - Physiological Computing - Heart Rate - Heart Rate Variability - Mediation Analysis - Adaptive Systems --- # The Ocular Command Center: How Eye Responses to Luminance, Color, Tunneling, and Visual Suppression Mediate Users' Physiological States in VR ## Citation Metadata - Authors: Andreia Valente, Augusto Esteves, Mark Billinghurst - Venue: CHI 2026 - Year: 2026 - DOI: https://doi.org/10.1145/3772318.3791328 - HTML: https://andreia-valente.com/publications/valente2026ocular.html - PDF: https://andreia-valente.com/pdfs/valente2026ocular.pdf ## Plain-Language Summary This paper introduces the Ocular Command Center framework for understanding how visual design in virtual reality can affect physiological state through the eyes. The study tested whether eye responses such as pupil diameter, blink behavior, fixation, and saccades mediate the relationship between VR visual parameters and cardiovascular responses such as heart rate and heart rate variability. Forty participants completed a spatial construction task in VR while experiencing manipulations of luminance, color temperature, peripheral occlusion, and periodic visual suppression. The study recorded synchronized eye tracking and cardiovascular data, then used mediation analysis to test whether ocular behavior acted as a bridge between visual parameters and bodily state. ## Method Participants used a Meta Quest 3 headset with integrated Tobii eye tracking. The experiment manipulated four visual dimensions: brightness, warm/cool color temperature, tunneling through peripheral occlusion, and simulated blink-like visual suppression. Measures included pupil diameter, blink rate, blink duration, fixation metrics, saccade metrics, heart rate, heart rate variability, and simulator symptom ratings. The study asks whether visual parameters act through a single generic arousal pathway or through distinct reflexive, cognitive, and perceptual pathways. ## Key Findings - Luminance reliably changed pupil diameter and was the only manipulation whose effect on heart rate was mediated by the pupil. - Color temperature affected heart rate variability without pupil mediation, suggesting a more appraisal-driven pathway. - Warm/yellow-biased color temperature produced strong nausea effects. - Peripheral occlusion changed pupil diameter and blink behavior but did not substantially affect cardiovascular measures. - Peripheral occlusion increased boredom while reducing some ocular symptoms, suggesting a trade-off between focus and engagement. - Visual suppression affected blink and fixation behavior and produced fatigue and eyestrain, but did not meaningfully shift cardiovascular state. - Eye tracking can help diagnose mechanisms, but ocular changes do not always predict cardiovascular change. ## Design Implications The paper argues that VR designers should not treat brightness, color, tunneling, and visual suppression as interchangeable arousal controls. Each visual manipulation has a different pathway and trade-off. Luminance may be useful for reflexive physiological modulation but can produce discomfort. Peripheral occlusion may narrow attention without increasing cardiovascular stress, but can reduce engagement. Color temperature requires caution because conscious detection of warm shifts may increase nausea. Visual suppression may be useful for perceptual research but appears poorly suited for comfort-oriented applications. ## Experimental Apparatus and Analysis The study used a Meta Quest 3 headset with Tobii Crystal XR5 eye tracking while participants completed a spatial construction task. The experiment recorded ocular measures including pupil diameter, blink rate, blink duration, fixation duration, and saccade behavior, along with cardiovascular measures including heart rate and heart rate variability. The analysis tested mediation pathways from visual parameters to eye responses and from eye responses to cardiovascular outcomes. The four visual manipulations were selected because they are common in VR design and comfort systems: luminance changes, color temperature shifts, peripheral occlusion or tunneling, and periodic visual suppression similar to blink-like blackouts. The paper asks whether these manipulations operate through a shared arousal pathway or through distinct reflexive, perceptual, and appraisal-based mechanisms. ## Detailed Results by Visual Manipulation Luminance produced the clearest eye-mediated cardiovascular pathway. Brightness reliably changed pupil diameter, and pupil response mediated the effect of luminance on heart rate. However, luminance extremes also carried comfort costs, including ocular symptoms and headache. The paper therefore treats luminance as powerful but fragile: useful for reflexive modulation, yet risky when pushed too far. Color temperature affected heart rate variability and simulator symptoms without the same pupil-mediated pathway. Warm yellow-biased color produced larger pupils than cool blue and was associated with stronger nausea, while cool light appeared more compatible with vigilance. Because these effects seem tied to conscious appraisal and perceptual salience, the paper recommends subtle color shifts rather than obvious yellow changes. Peripheral occlusion increased pupil diameter and changed blink behavior, but did not meaningfully shift heart rate or heart rate variability. It also reduced some ocular symptoms while increasing boredom, suggesting that tunneling can support focus or comfort at the cost of engagement. Gradual transitions may explain why occlusion did not produce strong autonomic arousal in this study. Visual suppression changed oculomotor behavior, including modest blink-rate increases and shorter fixation trends, but did not produce reliable cardiovascular modulation. Participants often perceived the blackouts as natural blinking, which blurred the boundary between external visual manipulation and internal bodily perception. This made visual suppression less promising as a wellness-oriented physiological control technique. ## Design Guidance and Research Gaps The authors recommend near-baseline luminance for parasympathetic recovery, avoidance of extreme brightness changes, brief and gradual peripheral occlusion for focus, subtle blue-biased color temperature when vigilance is desired, and caution with visual suppression because of fatigue and eyestrain. The study also shows that eye tracking is diagnostically valuable, but ocular metrics are not universal predictors of cardiovascular state. Future adaptive VR systems should treat ocular responses as part of a mechanism rather than just passive state labels. A system that detects pupil or blink changes still needs to know which visual manipulation caused them, whether the user consciously noticed the manipulation, and whether the resulting bodily state is desirable in context. ## Why This Paper Matters This work is relevant to adaptive VR, affective computing, eye tracking, psychophysiology, comfort design, and interoceptive interface research. It provides evidence that the eye is not merely a sensor of user state; in some cases, eye responses may be part of the mechanism linking visual design to physiology. ## Recommended Citation Valente, A., Esteves, A., & Billinghurst, M. (2026). The Ocular Command Center: How eye responses to luminance, color, tunneling, and visual suppression mediate users' physiological states in VR. In Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems. Association for Computing Machinery. https://doi.org/10.1145/3772318.3791328 ```bibtex @inproceedings{valente2026ocular, author = {Valente, Andreia and Esteves, Augusto and Billinghurst, Mark}, title = {The Ocular Command Center: How Eye Responses to Luminance, Color, Tunneling, and Visual Suppression Mediate Users' Physiological States in {VR}}, year = {2026}, booktitle = {Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems}, publisher = {Association for Computing Machinery}, doi = {10.1145/3772318.3791328}, url = {https://doi.org/10.1145/3772318.3791328} } ```