Method to Mitigate Nystagmus and Motion Sickness with Head Worn Visual Display during Vestibular Stimulation

Abstract

Motion sickness and complaints of dizziness caused by provocative vestibular stimulating environments have been a widespread problem, affecting a significant portion of the world’s population to varying degrees. The research objective was to determine if symptoms of motion sickness and associated nystagmus could be mitigated using an eye worn device which displayed an artificial horizon with a vertex point in the center for visual fixation, while experiencing vestibular stimulation. Assessment methods included an eye tracker, to measure velocity and duration of nystagmus, while patients underwent vestibular stimulation. This was followed by SSQ scoring to evaluate motion sickness symptoms. Users were tested with and without a visual display of specific symbology, while undergoing vestibular stimulation. Results demonstrated the associated nystagmus was significantly reduced in velocity and duration. With caloric stimulation testing, the duration of nystagmus was greater than 60 seconds in the group without the visual display but decreased to 3.3 seconds when using the displayed symbology and instructing the user to focus on the vertex point between the artificial horizon and centered vertical line. Eye speed of nystagmus was diminished from 13.6 degrees/second, to 0.4 degrees/second while using the visual display. Similar finding were noted with Barany Chair stimulation. The duration of nystagmus, which persisted for 25.8 seconds without the visual display, was decreased to 7.4 seconds when using display and focusing on the vertex point. The eye speed of nystagmus was also decreased from 26.3 degrees/second to 5.7 degrees/ second when using the visual display with vertex fixation. Objective SSQ scores were compared with and without visualization of the displayed symbology. When symbology was visualized, nausea, oculomotor symptoms, and disorientation were less apparent. In conclusion, using an eye worn device which displays specific user orientation symbology can mitigate the symptoms of motion sickness and related nystagmus when experiencing vestibular stimulation.