Influence of virtual heights and a cognitive task on standing postural steadiness

Virtual reality can simulate virtual heights and increase postural sway, while adding a cognitive task has a potential stabilization effect on posture stability. Our purpose was to observe the change of postural steadiness in different virtual heights, with or without an added-on cognitive task. Thirty young and healthy participants completed standing tasks in the real world and three virtual heights with or without a concurrent simple reaction time (SRT) task in a virtual environment. Most of the center of pressure parameters significantly increased while standing without an SRT task at virtual heights compared with the real world, but this difference was not observed while standing with an SRT task. The height-dependent effect for postural steadiness was not documented. Perceived distress scores were generally low and increased at exposure to the 12-m height compared to the 0-m height. There was no difference in SRT at the three virtual heights. Our results documented a destabilizing effect of a virtual environment, but were not able to confirm a height-dependent effect. A concurrent SRT task increased steadiness in virtual environment, and might have potentials being used as a training approach to enhance postural steadiness for at-height workers.