Postural stability and muscle co-activation among younger adults adapting to an immersive virtual reality.

Immersive visual environment can deceive our interoceptive perception of how we move relative to our environment. If the visual environment or a high reliance on vision produces straining work conditions, motion sickness or is associated with a medical disorder, the causes merit addressing. Therefore, the purpose of this study was to investigate whether postural control adapts to challenging visual environments from VR by adjusting postural stability and muscle co-contractions responses and investigate associations between stability measures and postural muscle co-contractions during VR-stimulation and control tests in quiet stance. Twenty-eight young adults participated (mean age 25.3 years, SD 4.6 years). In five sessions, they watched a VR simulation of a roller coast ride while a force platform recorded postural stability and electromyography recorded muscle co-contractions in leg muscles. Two control tests (quiet stance with eyes open and eyes closed), were performed before the VR sessions. The first VR session significantly increased the postural stability energy (p ≤ 0.002) and the muscle co-contraction levels (p ≤ 0.008) compared with the eyes open control test. Repeated VR sessions produced an adaptation that decreased postural stability energy (p ≤ 0.033) and muscle co-contraction levels (p ≤ 0.028). VR-stimulation made the association between postural stability responses and muscle co-contractions more prominent. Immersive visual environments can produce marked challenges to postural control, but the repeated experiences can also initiate sensory reweighting increasing resilience to visual disturbance.