Seasickness and partial peripheral vision obstruction with versus without an artificial horizon

• Two visual techniques for reducing motion sickness were tested using special glasses. • Peripheral vision obstruction delays the onset of symptoms by 36% • The same technique combined with an artificial horizon also delayed symptoms by 40% • No additional benefit was seen by combining both techniques over using a single one. Motion sickness (MS) is common when subjects are exposed to unfamiliar motion and affect individuals during travel. This study examines the immediate effect of two visual devices, in the form of glasses, on MS symptoms and associated physiological effects. The hypothesis is that peripheral vision obstruction reduces MS and that an additional beneficial effect could be observed when it is combined with an artificial horizon. Fifteen subjects with moderate to severe susceptibility to MS were exposed to a boat simulator in three conditions. Symptoms were assessed immediately after exposure. Time spent in the simulator, heart rate, and temperature were also recorded. The intensity of symptoms at the end of the experience did not differ, but time spent in the simulator before the onset of symptoms was significantly longer with peripheral vision obstruction (+36 %) and with both techniques combined (+40 %) than in the control condition. No difference was observed between the combined condition and peripheral vision obstruction alone. The glasses device used in this study (with or without an artificial horizon) delays the onset of symptoms. Further research is needed to confirm the mechanism that explains the benefits and to evaluate these effects during prolonged exposure to MS-inducing stimuli or after a period of familiarization with the device.