Investigating How Brain Stimulation Mitigates Motion Sickness Using Spatiotemporal Nystagmus Parameters Captured in...

Area of Science:

• Neuroscience
• Human-Computer Interaction
• Vestibular System

Background:

• Motion sickness is a common issue in virtual reality (VR) and other immersive technologies.
• Non-invasive cortical vestibular brain stimulation (vBS) is a potential countermeasure that enhances intrinsic resistance to motion sickness.
• The precise mechanism for vBS's online efficacy in mitigating motion sickness remains unclear.

Purpose of the Study:

• To investigate the relationship between motion sickness reduction and eye movement instability under vBS.
• To evaluate a 20 Hz-vBS approach targeting vestibular cortices as a motion sickness countermeasure.
• To explore sex-specific differences in the association between vBS, motion sickness, and eye movement metrics.

Main Methods:

• Utilized sham-controlled, sex-balanced eye-tracking data from an open-access database.
• Applied 20 Hz-vBS targeting vestibular cortices.
• Analyzed spatiotemporal eye movement metrics from eye-tracking data collected during VR exposure.
• Compared active vBS to sham vBS conditions.

Main Results:

• Active vBS significantly increased both temporary and spatial eye movement instability compared to sham vBS.
• This increase in eye movement instability was correlated with reduced motion sickness.
• Temporal eye movement metrics showed a stronger association with female participants, while spatial metrics were more associated with male participants.

Conclusions:

• vBS effectively reduces motion sickness by temporarily increasing eye movement instability.
• This study provides the first evidence linking vBS-induced motion sickness reduction to specific changes in eye movement dynamics.
• Findings suggest potential sex-specific mechanisms in vBS's efficacy for motion sickness mitigation.