Abstract: Visual cues strongly influence postural control and fall risk, yet direct comparisons between Mixed Reality (MR) and Virtual Reality (VR) on center‑of‑gravity (CoG) sway are limited. This study investigated the effects of RE (real environment), MR, and VR on CoG responses during quiet stance using moving‑light gaze guidance visual stimuli. Ten healthy adult participants completed 12 experimental tasks, it consists of 3 environments (RE, VR, MR) and 4 frequency conditions (no‑light, low, medium, high frequency). MR produced largest CoG sway than RE and VR for both Total Track Length (mean ΔTTL: MR = 315.69 ± 288.92 mm; RE = 221.18 ± 280.15 mm; VR = 167.44 ± 177.86 mm, n = 30) and Trajectory Length per Unit (mean ΔTraj: MR = 2.59 ± 2.36 mm; RE = 1.79 ± 2.30 mm; VR = 1.38 ± 1.46 mm, n = 30). This study results show that MR tended to elicit greater sway, compared to RE and VR.

Keywords: balance control, body sway, postural stability, rehabilitation, virtual and mixed reality, visual stimuli.