Vestibular nystagmus under hyperbaric conditions.

Sixty subjects participated in 454 experiments, 94 of which involved a centrifuge and an overload of 2 units. The studies showed that otolithic stimulation (the 2 unit overload) either activated nystagmus or had no substantial effect on the magnitude of this property. The paper advances a new, supplementary method for individual evaluation of the functional state of the vestibular analyzer of a pilot, in complicated cases of vestibulometry in clinical examinations, by comparative evaluation of the intensity of the nystagmic response under normal and hyperbaric conditions. Patients in whom the nystagmic slow phase speed (SPS) during hyperbaria (2 units) exceeds its usual value are designated as vestibulo-resistant; persons in whom the SPS of the nystagmus does not change substantially during hyperbaria are designated as vestibulo-susceptible.