title: Nausea induced by vection drum: contributions of body position, visual pattern, and gender.
abstract: BACKGROUND
  The purpose of this work was to investigate intrinsic (gender) and extrinsic factors (body position, visual pattern) and their relative contribution to the development of motion sickness during pseudo-rotation.
  
  
  METHODS
  A series of 3 experiments with 24, 12, and 48 subjects respectively, balanced for gender, was completed: Experiment 1 investigated the effect of body position (upright, supine) and gender; Experiment 2 investigated the additional influence of the visual pattern (dots, stripes), but only for the supine position; and Experiment 3 investigated the complex interaction of gender, body position, and visual pattern on symptom rating (SR), rotation tolerance (RT), and time to first perception of vection (VT). A novel vection drum that allowed varied body positions and visual patterns was used to create pseudo-rotation.
  
  
  RESULTS
  Experiment 1: there was a significant effect of rotation on SR, and a significant rotation x position interaction such that the rotation-induced symptom increase was significantly higher in the supine compared to the upright position. In addition, there was a significant effect of gender, with women showing lower SR in both positions. RT was lower while supine compared to upright; this effect was significantly more pronounced in male subjects. Experiment 2: a significant effect of rotation on SR was found, but no effect of the visual stimulus pattern or gender on SR, RT, or VT. Women exhibited significantly lower VT than men. Experiment 3: rotation induced a significant increase in SR independent of gender, body position, and visual pattern. Supine position induced significantly higher SR and RT than upright, and a significant interaction between gender, body position, and visual pattern.
  
  
  CONCLUSIONS
  The complex interaction of intrinsic and extrinsic factors may partially explain the mixed findings in the literature regarding the relationship of gender to motion sickness.
authors.affiliation: Department of Internal Medicine/Psychosomatics, University Hospital Tübingen, Tübingen, Germany.
authors.forename: Sibylle
authors.initials: S
authors.lastname: Klosterhalfen
authors.forename: Eric R
authors.initials: ER
authors.lastname: Muth
authors.forename: Sandra
authors.initials: S
authors.lastname: Kellermann
authors.forename: Karin
authors.initials: K
authors.lastname: Meissner
authors.forename: Paul
authors.initials: P
authors.lastname: Enck
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D009041:Motion Sickness / Q000209:etiology* / Q000503:physiopathology; D009325:Nausea / Q000209:etiology / Q000503:physiopathology; D011187:Posture; D012727:Sex Characteristics; D014785:Vision, Ocular