The Ocular Command Center: How Eye Responses to Luminance, Color, Tunneling, and Visual Suppression Mediate Users' Physiological States in VR

Paper Title

The Ocular Command Center: How Eye Responses to Luminance, Color, Tunneling, and Visual Suppression Mediate Users' Physiological States in VR

Publication Info

• Topic area: Investigating the physiological and subjective effects of visual parameters in virtual reality (VR) through eye metrics.
• Keywords: Virtual reality, eye tracking, luminance, color temperature, peripheral occlusion, visual suppression, physiological mediation, subjective symptoms, adaptive VR design, oculomotor behavior.

Background and Problem

• Problem / challenge: Current VR design frameworks assume visual effects primarily act through cognitive interpretation, neglecting the role of low-level eye metrics as mediators between visual manipulations and physiological or emotional outcomes.
• Significance: Understanding these mechanisms is crucial for creating adaptive VR systems that can predictably regulate user comfort, engagement, and physiological states, especially for therapeutic and wellness applications.
• Motivation and related work: Previous research has separately documented how visual parameters influence eye metrics and how eye metrics correlate with physiological responses. However, no studies have systematically tested whether eye metrics actively mediate these relationships, particularly in immersive VR environments.

Solution

• Proposed approach: The "Ocular Command Center" framework, which examines how visual parameters (luminance, color temperature, peripheral occlusion, and visual suppression) affect physiology and subjective experience through eye metrics.
• Novelty:
  1. Systematic mediation analysis of visual–eye–physiology pathways in VR.
  2. Empirical findings on distinct reflexive, cognitive, and discomfort-driven pathways linking visual parameters to physiological and subjective outcomes.
  3. Design guidelines for adaptive VR systems based on the identified pathways.
  4. Introduction of interoceptive illusions as a novel concept in VR psychophysiology.
• Procedure and key techniques:
  • Conducted a controlled within-subjects experiment with 40 participants using a Meta Quest 3 headset with integrated eye tracking.
  • Manipulated four visual parameters (luminance, color temperature, peripheral occlusion, and visual suppression) during a spatial construction task.
  • Measured eye metrics (pupil size, blink rate/duration, fixations, saccades), cardiovascular responses (heart rate, HRV), and subjective symptoms (via the Virtual Reality Symptom Questionnaire).
  • Applied mediation analysis to test whether eye metrics mediated the effects of visual parameters on physiological outcomes.

Results

• Concrete findings:
  • Luminance: Higher luminance decreased pupil diameter, increased blink rate, and mediated heart rate changes through pupil size. It produced the highest ocular symptoms and headaches.
  • Color temperature: Cooler (blue-biased) light reduced blink duration and increased fixation rates but did not mediate cardiovascular effects through pupil size. Warm light caused severe nausea.
  • Peripheral occlusion: Increased pupil diameter and blink rate but did not affect cardiovascular measures. It caused the highest boredom but the lowest ocular symptoms.
  • Visual suppression: Increased blink rate and reduced fixation duration without altering cardiovascular measures. It caused high eyestrain and fatigue.
• Advantage over baselines:
  • Identified distinct pathways (reflexive, cognitive, discomfort-driven) for visual–physiological coupling.
  • Demonstrated that only luminance mediated physiological effects via pupil size, while other parameters influenced subjective symptoms or attentional strategies.
• Experiments / evaluation:
  • Used a balanced Latin square design with four 4.5-minute experimental trials per participant.
  • Analyzed physiological and subjective responses across visual parameter conditions using Friedman tests, ANOVAs, and mediation analysis.
• Limitations and future work:
  • Single VR environment and task limit generalizability.
  • Parameter levels were exploratory and may not represent optimal ranges.
  • Short trial durations may have missed slower-developing effects.
  • Future work should explore adaptive, personalized systems and test findings in diverse VR contexts and tasks.

Summary

This study introduced the Ocular Command Center framework to examine how visual parameters in VR influence physiological and subjective outcomes via eye metrics. Key findings include luminance-mediated heart rate changes through pupil size, color temperature-induced nausea without pupillary mediation, and peripheral occlusion and visual suppression affecting subjective symptoms without systemic physiological effects. These results highlight distinct reflexive, cognitive, and discomfort-driven pathways, offering actionable insights for designing adaptive VR systems. Future research should validate these findings across diverse environments and explore real-time personalization to optimize user comfort and engagement.