Title:“A methodological comparison of real and virtual visual perturbations on postural stability and the role of aging”
Thesis Supervisor: Dr. Mark G. Carpenter
Committee Members: Dr. Romeo Chua, Dr. J. Timothy Inglis
Abstract: Balance control requires the continuous integration of sensory information to maintain postural stability. Widely accessible virtual reality (VR) technology can be used to directly manipulate stimuli presented to the visual system, and subsequent postural responses can then be characterized. This manipulation is of particular importance for older adults, who tend to have greater reliance on vision for balance control. At present, there are substantial differences in the visual sensory cues presented in VR compared to the real-world. As such, previous real-world research investigating vision and postural stability cannot be assumed as directly transferrable to applications in VR.
The primary purpose of this thesis is to compare the presentation of real and virtual visual perturbations on evoked postural responses. The secondary purpose is to explore the degree to which these responses differ between healthy younger and older adults. It is hypothesized that real visual perturbations will evoke larger and more coherent postural responses than those presented in VR. Additionally, regardless of the modality, older adults will be more highly perturbed and responsive to visual stimuli than younger adults.
The project will be comprised of two studies, evaluating transient and continuous visual perturbations, respectively. Perturbations will be presented in a physical moving room, translating randomly in forward and backward directions. The moving room will be re-created to scale in VR and presented in a head-mounted display system.
This research will contribute to our understanding of how various visual perturbation methodologies may differentially influence postural stability. Completion of this project will provide an evidentiary basis for the usability of VR for future perturbation-based investigations with both younger and older adults.