Visually-induced Motion Sickness by 3D Movie and changes of energy metabolism

1.Rotational movement of 3D video images causing visually-induced motion sickness was analyzed to examine how the gravity contributes to induce visually-induced motion sickness。While an angle of a rotation axis of 3D video image from the gravity direction，and its angle from subjective vertical which was perceived by viewers through 3D video image，were varied，the severity of visually-induced motion sickness was measured.2.Twelve students(8males And4females)，ranging in age from20to25years，participated in this study as subjects.2.None of the subjects reported any medical problems and all presented with normal vestibular functions.Nine optokinetic stimuli of 3D video images were produced by computer graphics that drew an inside view of a virtual room(10mW×10mD×6mH)。In each stimulus，rotation axis of video image tilted at 0，45，or 90 deg with respect to the viewers‘vertical(The Gravity Direction)，and visually-induced subjective vertical(the vertical direction in the virtu…More al room)was inclined at 0，45，or 90 deg with respect to the rotation axis。Video images were projected to a140 inch screen for 3D display that was positioned 3m ahead of the subjects in a dark room.View angles for the subjects were 54 degree horizontally and 40 deg vertically.Each stimulus was presented to the subjects for 45s with interstimulus intermission of 15s.A rest of 2minutes was given after every6stimuli.The severity of visually-induced motion sickness was measured by the method of paired comparison；i.e.，discomfort caused by 3D video image was subjectively compared between pairs provided in series.It was then transformed into a distance measure in accordance with the law of comparative judgement of Thurstone，case V.Severity comparisons were performed 210times by every subject(30times In Each Experiment).3.The severity of visually-induced motion sickness was enhanced as tilt angle of the image rotation axis from the gravity direction was increased.It was also enhanced as inclination of the subjective vertical was increased with respect to the image rotation axis.The distance measure of the severity of visually-induced motion sickness(MS)was analyzed by multi variable regression with the horizontal component of angular velocity of image rotation(i.e.，vertical rotation component)(OK‘h)，angular velocity of rotation of subjective vertical(SV’)，and angular acceleration of rotation of subjective vertical(SV‘’)。Then it was expressed as MS=0.45 OK‘h+0.73SV’+0.19SV‘’+MS I D20 ii D2，where MS0is a constant.4.These results indicated that rotation of subjective vertical contributes importantly to evoke visually-induced motion sickness。Thus，it was suggested that visually-induced motion sickness attributes to sensory conflict between the visual and the equilibrium sensations in perception of the vertical(Gravitational Direction)as well as in perception of rotation。Less：Less

1.Rotational movement of 3D video images causing visually-induced motion sickness was analyzed to examine how the gravity contributes to induce visually-induced motion sickness. While an angle of a rotation axis of 3D video image from the gravity direction, and its angle from subjective vertical which was perceived by viewers through 3D video image, were varied, the severity of visually-induced motion sickness was measured.2.Twelve students(8 males and 4females), ranging in age from 20 to 25 years, participated in this study as subjects. None of the subjects reported any medical problems and all presented with normal vestibular functions. Nine optokinetic stimuli of 3D video images were produced by computer graphics that drew an inside view of a virtual room (10mW×10mD×6mH). In each stimulus, rotation axis of video image tilted at 0, 45, or 90 deg with respect to the viewers' vertical (the gravity direction), and visually-induced subjective vertical (the vertical direction in the virtu … More al room) was inclined at 0, 45, or 90 deg with respect to the rotation axis. Video images were projected to a 140 inch screen for 3D display that was positioned 3 m ahead of the subjects in a dark room. View angles for the subjects were 54 degree horizontally and 40 deg vertically. Each stimulus was presented to the subjects for 45 s with interstimulus intermission of 15 s. A rest of 2 minutes was given after every 6 stimuli. The severity of visually-induced motion sickness was measured by the method of paired comparison ; i.e., discomfort caused by 3D video image was subjectively compared between pairs provided in series. It was then transformed into a distance measure in accordance with the law of comparative judgement of Thurstone, case V. Severity comparisons were performed 210 times by every subject (30 times in each experiment).3.The severity of visually-induced motion sickness was enhanced as tilt angle of the image rotation axis from the gravity direction was increased. It was also enhanced as inclination of the subjective vertical was increased with respect to the image rotation axis. The distance measure of the severity of visually-induced motion sickness (MS) was analyzed by multi variable regression with the horizontal component of angular velocity of image rotation (i.e., vertical rotation component) (OK'h), angular velocity of rotation of subjective vertical (SV'), and angular acceleration of rotation of subjective vertical (SV''). Then it was expressed as MS=0.45OK'h+0.73SV'+0.19SV''+MSィイD20ィエD2, where MS0 is a constant.4.These results indicated that rotation of subjective vertical contributes importantly to evoke visually-induced motion sickness. Thus, it was suggested that visually-induced motion sickness attributes to sensory conflict between the visual and the equilibrium sensations in perception of the vertical (gravitational direction) as well as in perception of rotation. Less