Exploratory study for the EEG characteristics of visual-vestibular conflict induced motion sickness

Motion sickness, commonly introduced by conflicting visual-vestibular inputs, remains inadequately characterized at the neurophysiological level, with limited quantitative biomarkers for sensory conflict detection. This study investigated electroencephalographic (EEG) activity patterns associated with varying degrees of visual-vestibular congruence to identify potential neural correlates of sensory conflict. Six healthy participants (aged 18-22 years) underwent controlled motion stimuli while EEG data were recorded using a wireless system. Participants were seated in an electrically powered wheelchair traversing a 3-meter linear track under three experimental conditions: (1) congruent visual-vestibular stimuli, (2) vestibular stimulation without visual input, and (3) conflicting visual-vestibular information. Both forward and backward motion were explored. Spectral analysis of EEG data revealed condition-dependent variations in neural oscillations. Notably, delta-band (1-4 Hz) power demonstrated the highest magnitude during visual-vestibular conflict and the lowest during congruent stimulation. Direction-specific effects were observed, with significant differences in delta and alpha band power between forward and backward motion, particularly in the central (Cz) and right occipital (O2) regions. These findings suggest that EEG spectral signatures may serve as objective indicators of sensory conflict during motion, potentially informing early detection strategies and therapeutic interventions for motion sickness.