MOTION SICKNESS SUSCEPTIBILITY TO OPTOKINETIC ROTATION CORRELATES TO PAST HISTORY OF MOTION SICKNESS

Purpose: This study investigated correlations between motion sickness susceptibility to a rotating optokinetic drum and past history of moti on sickness. Method: There were 49 subjects who filled out a questionn aire on motion sickness history (MSH) who participated in the experime nt. Each subject sat in an optokinetic drum for a 12-min baseline and a 12-min drum rotation period. Subjects' motion sickness symptoms (MSS ) and electrogastrograms (EGG's) were measured. Results: There were si gnificant correlations between MSH scores and MSS scores during drum r otation (r = 0.5392, p < 0.001), and between MSH scores and EGG 4-9 cy cles per minute (cpm) spectral intensity ratios between drum rotation and baseline periods (r = 0.5320, p < 0.001). Further analysis indicat ed that the mean MSS scores during the drum rotation period were 11.50 for the top 33% MSH scorers, 4.18 for the middle 34% MSH scorers, and 3.63 for the bottom 33% MSH scorers. The mean EGG 4-9 cpm spectral in tensity ratios between drum rotation and baseline periods were 2.62 fo r the top 33% MSH scorers, 1.44 for the middle 34% MSH scorers, and 1. 21 for the bottom 33% MSH scorers. Conclusion: These results indicated that past history of motion sickness correlates with severity of moti on sickness provoked by optokinetic rotation.