[Pattern of Body Sway While Viewing 3D Video Clips in Various Age Groups].

These days, developments in graphical technology have resulted in an increase in the chance to view 3D video clips. Visually induced motion sickness (VIMS) has been widely reported as a negative result of viewing these clips. The onset of VIMS is explained by some hypotheses. However, the root causes of VIMS have not been elucidated yet, whereas dizziness and nausea are regarded as symptoms of VIMS. In this study, we focus on the difference in the pattern of body sway among age groups and examine whether the consistency between the background and the viewpoint motion depends on the severity of VIMS. This experiment was conducted with 116 subjects aged 15-89 years. They peripherally viewed a 3D video clip showing a sphere whose motion was consistent with their viewpoint (VC-I) and another 3D video clip of a sphere whose motion was inconsistent with their viewpoint (VC-II). Statokinesigrams (SKGs) were recorded with their eyes open and with their eyes closed for 60 s. The amount of sway was calculated from the SKGs. Results showed that for all age groups, sway values were significantly higher when viewing the 3D video clip (VC-II) than in the Pre. However, for the elderly, there was no significant difference between the sway values while viewing the VC-I and those in the Pre. Results suggest that VIMS might not occur in the elderly because of the deterioration of their visual function, such as visual acuity and accommodation, with advancing age.