A unique sound alleviates motion sickness

Summary

A research group led by Takumi Kagawa and Masashi Kato at Nagoya University Graduate School of Medicine has discovered that using “a unique sound stimulation technology”—a device that stimulates the inner ear with a specific wavelength of sound—reduces motion sickness. Even a single minute of stimulation reduced the staggering and discomfort felt by people that read in a moving vehicle. The results, published in Environmental Health and Preventive Medicine, suggest a simple and effective way to treat this common disorder. “Our study demonstrated that short-term stimulation using a unique sound called 'sound spice®' alleviates symptoms of motion sickness, such as nausea and dizziness,” Kagawa said. “The effective sound level falls within the range of everyday environmental noise exposure, suggesting that the sound technology is both effective and safe.” The discovery is an important expansion of recent findings about sound and its effect on the inner ear. Increasing evidence has suggested that stimulating the part of the inner ear associated with balance using a unique sound can potentially improve balance. Using a mouse model and humans, the researchers identified a unique sound at 100 Hz as being the optimal frequency. “Vibrations at the unique sound stimulate the otolithic organs in the inner ear, which detect linear acceleration and gravity,” Kato explained. “This suggests that a unique sound stimulation can broadly activate the vestibular system, which is responsible for maintaining balance and spatial orientation.” To test the effectiveness of the devices, they recruited voluntary participants who were exposed to the unique sound. Following the stimulation, motion sickness was induced by a swing, a driving simulator, or riding in a car. The researchers used postural control, ECG readings, and Motion Sickness Assessment Questionnaire results to assess the effectiveness of the stimulation. Exposure to the unique sound before being exposed to the driving simulator...