title: Simulator sickness when performing gaze shifts within a wide field of view optic flow environment: preliminary evidence for using virtual reality in vestibular rehabilitation.
abstract: BACKGROUND: Wide field of view virtual environments offer some unique features that may be beneficial for use in vestibular rehabilitation. For one, optic flow information extracted from the periphery may be critical for recalibrating the sensory processes used by people with vestibular disorders. However, wide FOV devices also have been found to result in greater simulator sickness. Before a wide FOV device can be used in a clinical setting, its safety must be demonstrated. METHODS: Symptoms of simulator sickness were recorded by 9 healthy adult subjects after they performed gaze shifting tasks to locate targets superimposed on an optic flow background. Subjects performed 8 trials of gaze shifting on each of the six separate visits. RESULTS: The incidence of symptoms of simulator sickness while subjects performed gaze shifts in an optic flow environment was lower than the average reported incidence for flight simulators. The incidence was greater during the first visit compared with subsequent visits. Furthermore, the incidence showed an increasing trend over the 8 trials. CONCLUSION: The performance of head unrestrained gaze shifts in a wide FOV optic flow environment is tolerated well by healthy subjects. This finding provides rationale for testing these environments in people with vestibular disorders, and supports the concept of using wide FOV virtual reality for vestibular rehabilitation.
authors.affiliation: Department of Physical Therapy, University of Pittsburgh, Pittsburgh, PA, USA. psparto@pitt.edu.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Sparto
authors.forename: Susan L
authors.initials: SL
authors.lastname: Whitney
authors.forename: Larry F
authors.initials: LF
authors.lastname: Hodges
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Furman
authors.forename: Mark S
authors.initials: MS
authors.lastname: Redfern