Lack of gender difference in motion sickness induced by vestibular Coriolis cross-coupling.

It has been reported that females are more susceptible to motion sickness than males. Supporting evidence is primarily based on retrospective survey questionnaires and self-reporting. We investigated if there is a gender difference in motion sickness susceptibility using objective and subjective measurements under controlled laboratory conditions. Thirty healthy subjects (14 males and 16 females) between the ages of 18-46 years were exposed to Coriolis cross-coupling stimulation, induced by 120 degrees /s yaw rotation and a simultaneous 45 degrees pitch forward head movement in the sagittal plane every 12 seconds. Cutaneous forearm and calf blood flow, blood pressure, and heart rate were monitored. Graybiel's diagnostic criteria were used to assess sickness susceptibility before and after motion exposure. Golding and Kerguelen's scale was used to assess the severity of symptoms during motion exposure. A significant (p<0.01) increase of forearm and calf blood flow during cross-coupling stimulation was observed in both sexes. However, the subjective symptoms rating and blood flow measurements indicate that there was no significant difference between male and female subjects. Our data also suggests that females may be more inclined to admit discomfort as indicated by their responses to a survey of motion sickness history prior to the experiment.