Changes in Eye Movements and Body Sway While Viewing Stereoscopic Movies Under Controlled Consciousness

摘要

In our previous study, we found that it is possible to have an effect of change in the condition of consciousness (allocation of consciousness) on visually evoked postural responses (VEPRs) and subjective symptoms of visually induced motion sickness (VIMS). Thus, in this study, we verified the effect of controlling consciousness on body sway and eye movements while participants viewed stereoscopic movies. Participants watched a three-dimensional movie consisting of several colored balls that moved sideways sinusoidally at 0.25 Hz for 180 s after pre-instruction. Pre-instructions included "uncontrolled consciousness," "keep a static, upright posture," and "sway body in the same/opposite direction." This study recorded both center of pressure, as body sway, and electrooculography (EOG) data, as eye movements. Recorded EOG data were converted to eye movement velocity. The results clearly showed that (1) the influence of the pre-instruction appeared to be much stronger than that of the VEPRs, (2) the pre-instruction changed the frequency of the saccade, or interquartile range of eye movement, velocity histogram according to each task as measured by changes in retinal slip velocity, and (3) the condition of consciousness that controlled body motion changed the participants' postural instability and eye movement results. Thus, after considering many theories for the origin of VIMS, we concluded that the condition of consciousness controlled VIMS.