Gender differences in susceptibility to vection-induced motion sickness and gastric myoelectric activity

The researcher expected to find that women show higher incidence of and greater severity in symptoms of motion sickness (SMS). In Phase 1, 485 subjects reported on their previous incidence of motion sickness between ages 12-25 on various forms of motion. Analysis of variance (ANOVA) indicated women reported significantly greater incidence of motion sickness than men did. In Phase 2, each of 47 subjects viewed an optokinetic rotating drum for 8-minute baseline (BL) and 16-minute drum rotation (DR) periods. During DR, subjects' subjective SMS were measured. ANOVA on SMS scores showed no significant gender difference in severity of SMS. Subjects' electrogastrograms (EGGs) and the ratios of spectral intensity at 4-9 cycles/min (cpm) between DR and BL periods, gastric tachyarrhythmia, were also obtained. ANOVA appropriate for equal or unequal variance depended on the results of Levene's test for homogeneity of variance. Results indicated women reported more incidence of motion sickness history. Men and women did not differ in subjective symptoms of motion sickness when exposed to motion stimuli. Men developed more severe gastric tachyarrythmia during motion than women did. Subjective reports of previous motion sickness incidence may not accurately indicate gastric tachyarrhythmia during motion.