Vestibular function in military pilots before and after 10 s at +9 G z on a centrifuge

Vestibular Laboratory, Institute of Aviation Medicine, Beijing, P. R. China.
Aviation Space and Environmental Medicine (Impact Factor: 0.88). 02/2009; 80(1):20-3. DOI: 10.3357/ASEM.2186.2009
Source: PubMed


Effects of high Gz acceleration can threaten flight safety through loss of consciousness or a lesser-known phenomenon, G-induced vestibular dysfunction (GIVD). There are reports of GIVD following high-G flight or centrifuge exposure. The aim of this study was to explore this problem under controlled conditions using a human centrifuge.
There were 11 pilots who were exposed to +9 Gz for 10 s. Measurements were made before and after G exposure to assess vestibular function, including spontaneous nystagmus, positioning nystagmus, optokinetic nystagmus, vestibular ocular reflex, vestibular-vision interaction, subjective vision vertical perception, and vestibular-evoked myogenic potentials.
No significant change was found for vestibular function after the Gz exposure.
It appears +9 Gz for 10 s does not produce GIVD. However, the possible effects of prolonged high G maneuvers in modern aircraft combined with head movements may warrant further study.

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