Masseteric vestibular evoked myogenic potentials findings in individuals with motion sickness susceptibility.

Background: Motion sickness (MS) is a clinical condition that causes autonomic symptoms as a result of a mismatch in sensory inputs with unusual body and environmental movements. Although the cause of MS is not clearly established, one widely accepted theory is otolith asymmetry and canal-otolith conflict. Masseteric vestibular evoked myogenic potentials (mVEMPs) are short latency inhibitory potentials recorded from the bilateral masseter muscle in response to bilateral or unilateral galvanic/acoustic stimuli. Studies have shown that mVEMP evaluates the integrity of the vestibulo-trigeminal pathway and the generator region is the saccule in common with cVEMP.

Objective: Our study aimed to evaluate the function of the otolith organ and vestibulo-trigeminal pathway in people with high susceptibility to MS via mVEMP.

Methods: According to the Motion Sickness Susceptibility Questionnaire-Short Form (MSSQ-SF), 21 people with 70-100% susceptibility (high susceptibility) and 20 people with 0-30% susceptibility (low susceptibility) were included in the study. Participants have normal hearing and do not have any additional disorders. All participants underwent mVEMP evaluation.

Results: There was no statistical difference in P1, N1 absolute latency, N1-P1 inter-wave latency, N1-P1 amplitude, interaural amplitude asymmetry ratios at 100 dB nHL, and mVEMP thresholds in the high and low susceptibility groups.

Conclusions: Our study obtained no findings suggesting saccule and vestibulo-trigeminal involvement in people high susceptible to motion sickness.