Gender and the nocebo response following conditioning and expectancy.

Objective: To investigate the role of Pavlovian conditioning and expectancy and of gender on the nocebo effects.

Methods: Conditioning experiment: Forty-eight healthy male and female volunteers were investigated for 3 days using a standard rotation procedure. Subjects in the experimental group received a salient oral stimulus prior to rotation; subjects in the control group received the stimulus 12 h after rotations on Days 1 and 2; on Day 3, all subjects received the stimulus prior to rotation.

Nausea induced by vection drum: contributions of body position, visual pattern, and gender.

Introduction: 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.

Gender and race as determinants of nausea induced by circular vection.

Background: Within- and between-subject variability of susceptibility for motion sickness is well established, but which factors determine susceptibility is less well known.

Objective: We investigated whether and to what degree sex, race, and head movements contribute to the development of nausea and vomiting (N&V) during pseudorotation in a vection drum in healthy participants.

Methods: Male and female, Chinese and white subjects were exposed to 5x1 minute of circular vection in a conventional rotation drum, with half of the participants performing nausea-enforcing head movements.

Effects of ethnicity and gender on motion sickness susceptibility.

Introduction: Susceptibility to motion sickness (MS) is known to be affected by gender and ethnic origin, but whether gender and ethnicity are interacting is unknown.

Methods: We investigated MS development in healthy Caucasian subjects (n = 227), and in subjects of Chinese origin (n = 82). All subjects were exposed to nausea-inducing body rotations in a rotation chair, and rotated around the yaw axis for 5 x 1 min, while they were instructed to move their heads.