The Influence of Expectation on Motion Sickness Severity

Abstract

According to the spatial orientation motion sickness model, motion sickness occurs when the sensed vertical as determined by sensory information is at variance with the expected vertical based on previous experience. Since it is known that cognition can affect self-motion perception, the expected vertical was manipulated through imagination to discover whether motion sickness severity could be increased with incongruent imagination, and decreased with congruent imagination, both with respect to actual self-motion. Subjects were blindfolded, and exposed to lateral motion on a parallel swing. Motion sickness severity was found to increase over time, in the incongruent condition only. However, post hoc analyses showed no differences in motion sickness severity across individual time points. The findings are discussed in terms of statistical procedures and the experimental setup. Recommendations for future research are proposed.