ABSTRACT
PURPOSE: This study evaluated the effects of short term and extended viewing of virtual imagery using the Binocular Viewer (new generation bi-ocular viewer) on the visual system of children, and compared these effects with that of viewing a high definition television (HDTV) display. METHODS: Sixty children aged 5 to 16 years viewed 30 min of virtual imagery using the Binocular Viewer and a HDTV display on two occasions. Sixteen subjects, aged 13 to 16 years, completed a third session of extended viewing (80 min) with the Binocular Viewer. Oculomotor function and symptoms were assessed previewing, immediately postviewing, and 10 min postviewing. RESULTS: Thirty minutes of Binocular Viewer use resulted in symptom increases (p < 0.05) immediately postviewing ("feeling tired," "feeling sleepy," "difficulty concentrating," and "sore/aching eyes") however most symptoms had dissipated by 10-min postviewing. There were no significant symptom differences between viewing with the Binocular Viewer and the HDTV display at either time point. An increase in symptoms (p < 0.05) immediately postviewing was recorded after 80 min of Binocular Viewer use ("feeling tired," "feeling bored," "feeling sleepy," and "tired eyes"), however only "feeling tired" and "feeling bored" remained significantly increased (p < 0.05) 10-min postviewing. Near unaided visual acuity demonstrated a significant and consistent reduction immediately (p < 0.01) and at 10 min (p < 0.05) following 30 min of Binocular Viewer use and immediately following 80 min of use (p < 0.01). Near unaided VA was also significantly reduced (p < 0.01) immediately after 30 min of HDTV display use. CONCLUSIONS: Virtual imagery viewing with the Binocular Viewer in children aged 5 to 16 years had few additional adverse effects when compared to viewing a more conventional HDTV display. The Binocular Viewer was comfortable to wear for up to 80 min of viewing. The consistent reduction in near vision for both viewing durations with the Binocular Viewer requires further investigation.
Subject(s)
Data Display , Eye Movements/physiology , Oculomotor Muscles/physiology , User-Computer Interface , Vision, Binocular , Accommodation, Ocular , Adolescent , Child , Child, Preschool , Convergence, Ocular , Cross-Over Studies , Depth Perception , Equipment Design , Female , Head , Humans , Male , Strabismus/physiopathology , Surveys and Questionnaires , Television , Time Factors , Visual AcuityABSTRACT
PURPOSE: Virtual reality devices, including virtual reality head-mounted displays, are becoming increasingly accessible to the general public as technological advances lead to reduced costs. However, there are numerous reports that adverse effects such as ocular discomfort and headache are associated with these devices. To investigate these adverse effects, questionnaires that have been specifically designed for other purposes such as investigating motion sickness have often been used. The primary purpose of this study was to develop a standard questionnaire for use in investigating symptoms that result from virtual reality viewing. In addition, symptom duration and whether priming subjects elevates symptom ratings were also investigated. METHODS: A list of the most frequently reported symptoms following virtual reality viewing was determined from previously published studies and used as the basis for a pilot questionnaire. The pilot questionnaire, which consisted of 12 nonocular and 11 ocular symptoms, was administered to two groups of eight subjects. One group was primed by having them complete the questionnaire before immersion; the other group completed the questionnaire postviewing only. Postviewing testing was carried out immediately after viewing and then at 2-min intervals for a further 10 min. RESULTS: Priming subjects did not elevate symptom ratings; therefore, the data were pooled and 16 symptoms were found to increase significantly. The majority of symptoms dissipated rapidly, within 6 min after viewing. Frequency of endorsement data showed that approximately half of the symptoms on the pilot questionnaire could be discarded because <20% of subjects experienced them. CONCLUSIONS: Symptom questionnaires to investigate virtual reality viewing can be administered before viewing, without biasing the findings, allowing calculation of the amount of change from pre- to postviewing. However, symptoms dissipate rapidly and assessment of symptoms needs to occur in the first 5 min postviewing. Thirteen symptom questions, eight nonocular and five ocular, were determined to be useful for a questionnaire specifically related to virtual reality viewing using a head-mounted display.
