ObjectiveVisually induced motion sickness (VIMS) and increased postural sway are two adverse side effects that may occur when viewing motion stimuli. However, whether these effects are elevated to a greater extent when viewing stereoscopic 3D motion stimuli, compared to 2D stimuli on a TV screen, has not been investigated under controlled circumstances. Therefore this study aimed at investigating VIMS and postural sway before, during, and directly after viewing 2D and 3D motion stimuli, on a commonly available TV screen. Method16 Participants were exposed to an aviation documentary shown in 2D and in 3D on separate occasions. Before, during, and after exposure, VIMS and postural sway were measured. VIMS was quantified by a rating scale giving a single number, and by a multi-symptom questionnaire that assessed multiple VIMS symptoms separately. Sway path length, standard deviations and short-range and long-range scaling components of the center of pressure were calculated as measures of postural sway. ResultsVIMS symptom severity, as obtained with the single rating scale, did not show a significant increase to either 2D or 3D exposure. The multi-symptom questionnaire did reveal significant increases in VIMS symptom severity to both 2D and 3D exposure. However, VIMS was not significantly more increased in case of 3D exposure compared to 2D exposure. All postural sway measures (sway path length, standard deviation in mediolateral and anteroposterior direction, as well as the short-range scaling components) increased significantly as a result of exposure. None of the postural sway measures was differentially affected to 3D as compared to 2D exposure. ConclusionViewing 3D motion stimuli did not cause more serious VIMS symptoms, compared to viewing motion stimuli in 2D. We attribute this lack of difference to the fact that the 3D effects in this documentary were optimized for viewing in a cinema, the projection on the TV-screen thus causing quarantining of the visual input. The increase in postural sway, irrespective of image type, may reflect exploratory behavior, allowing the participant to gain more information about self-orientation with respect to the virtual environment.