Short-term changes in binocular and accommodative function following immersive VR head-mounted display exposure

Virtual reality head-mounted displays (VR-HMDs) impose visual demands that differ from natural viewing conditions, particularly because of the vergence–accommodation conflict generated by immersive stereoscopic displays. This exploratory study evaluated immediate changes in binocular and accommodative visual performance after brief VR-HMD exposure in adults. Using a single-group pre–post design, fifty-four participants underwent optometric assessment before and immediately after 15 min of exposure to a Samsung Gear VR head-mounted display. Near point of convergence, stereoacuity, accommodative facility and near cover test findings were assessed. Pre–post changes were analysed using paired statistical tests and adjusted linear regression models were fitted to explore factors associated with the magnitude of change. After VR-HMD exposure, minor measurable cover test changes were observed in 16 participants, all of 1 prism dioptre and in both exophoric and esophoric directions. Near point of convergence increased slightly, whereas stereoacuity and accommodative facility showed better post-exposure test performance. Baseline stereoacuity and baseline accommodative facility were significantly associated with their respective pre–post changes, while age, spherical equivalent, glasses use and contact lens use were not significant predictors. These findings describe small and heterogeneous changes in visual test performance following brief recreational VR-HMD exposure, without a consistent pattern of deterioration; as no non-VR control condition was included, these changes may reflect VR-related effects, repeated testing or both. From a display-human interaction perspective, objective binocular and accommodative measures may provide useful information when evaluating visual performance, comfort and short-term user response to VR-HMD systems.