Perception and Precision: How VST and OST Headsets Influence Task Execution

Background: Head-mounted displays (HMDs) offer compelling virtual and augmented experiences, yet their influence on everyday accuracy and efficiency is not fully understood. In particular, video see-through (VST) and optical see-through (OST) devices may introduce perceptual distortions that degrade performance. Methods: We compared a VST HMD (Meta Quest 3) and an OST HMD (Microsoft HoloLens) in two representative motor tasks: dart throwing (far-field interaction) and bottle filling (near-field interaction). Eighty volunteers were split into two experiments, each using one HMD type. Every participant performed both tasks twice—once with the assigned HMD and once with normal vision. Completion time, dart-board error, water-level deviation, and selfreported visual-discomfort symptoms (eyestrain, blurred vision, nausea) were recorded. Results: Wearing either HMD lengthened task completion and reduced precision relative to the naked-eye baseline. Dart throws landed farther from the bullseye and showed greater score variability under HMD conditions. In the bottle-filling task, participants overfilled more frequently and deviated further from the target water level when using an HMD. Mild visual discomfort was reported by some users, whereas severe symptoms were rare. Conclusions: Both VST and OST HMDs can impose perceptual and cognitive demands that impair speed and accuracy in common near- and farfield activities. Refining calibration procedures and real-time visual feedback may mitigate these effects; broader studies across diverse user groups and task domains are warranted.