Evaluation and modeling of human posture and balance in response to sensory inputs in a virtual environment

Balance control, spatial orientation and upright posture require an accurate integration of sensory inputs. In order to understand the integration in terms of motor learning and balance improvement, experiments were conducted in a virtual environment. The objectives of the current work were to: 1) examine the postural muscle responses, head movements, and game performance in young healthy subjects when they were exposed to unpredictable situations in the virtual environment 2) examine the extent of learning transfer that occurred in the virtual environment to the real world by means of pre and post posture tests 3) propose and validate the theoretical model that simulates experimental results. Results revealed that game performance increased during training in the virtual environment. The postural test results, electromyogram and head movement data have implications in using the virtual environment in balance and vestibular rehabilitation, for alleviating simulator sickness symptoms, and enhancing spatial knowledge and memory. The model simulates the experimental results very closely and sheds light on the activation of muscles under specific situations encountred in the environment. Overall, the experimental results supported our hypothesis.