Implications of balance disturbances following exposure to virtual reality systems

As we move our heads and bodies, and travel though our real world, the human organs of equilibrium (the vestibular system) integrate the information from the visual and proprioceptive systems and compare them. A useful analogue is the fire control system for a gun mounted on a moving vehicle such as a battleship. It is our opinion that many virtual reality (VR) systems, like many ground based flight simulators, alter the natural correspondences between these sensory inputs and when the exposure to the VR environment is protracted, the sensory systems are recalibrated to accommodate the new relationships. These recalibrations, when they involve the vestibular system, can result in balance disturbances, and these latter can outlast the period that an individual remains under the control of the person or entity that exposed that individual to the VR system. If a person should trip when leaving the building, or later when driving home, safety could be compromised and product liability could be incurred. We review our experiences with balance disturbances in flight trainers and describe recent findings with an automated postural equilibrium assessment system which can be employed before and after exposure in order to certify that no observable changes are evident in a subject or user.