An Investigation of the Pathogenesis in Pilots With Airsickness Susceptibility Using Cervical Vestibular Evoked...

The aim was to compare cervical vestibular evoked myogenic potential (cVEMP) findings between pilots who are susceptible to airsickness and those who are not and to determine whether the physiopathology arising from the sacculo-collic reflex pathway occurs during episodes of airsickness in pilots.

The patient group included 32 male pilots susceptible to airsickness, and the control group included 30 male pilots with no airsickness susceptibility. Participants with hearing loss and neuromuscular pathology were excluded. The Graybiel scale and cVEMP test were administered to the participants. The cVEMP thresholds, wave latencies and amplitudes, and interaural amplitude asymmetry ratios (IAARs) were compared between the groups. In addition, correlation analysis was performed between IAAR and susceptibility to airsickness severity in the airsickness susceptible (AS) group.

The right-ear cVEMP threshold in the AS group (85.62 ± 6.05) was lower than that of the control group (91.16 ± 4.85; p < .001). In the right ears of the AS group, the P1 and N1 latencies at 100, 95, and 90 dB nHL levels were found to be shorter than those of the control group (p < .05 for all). Again, the P1N1 wave amplitudes at 100 dB nHL in the right ears of the AS group were higher than those of the control group (p = .009). The IAAR was higher in the AS group than in the control group (p < .001). There was a positive correlation between IAAR and airsickness susceptibility severity in the AS group (ρ = .742, .650, .535 at 100, 95, 90 dB nHL, respectively).

The susceptibility of pilots to airsickness may be related to changes in normative cVEMP latencies and amplitudes. The present study demonstrated a correlation between asymmetry in the integrity of the saccular reflex pathway and the severity of pilots' susceptibility to airsickness. A higher IAAR was observed in subjects with a greater susceptibility to airsickness, indicating a potential correlation between the two variables.

https://doi.org/10.23641/asha.28300112.