Pupillary response in air force and air defence pilots when exposed to Gz+ acceleration

Abstract

Background/Aim. In aviation, visual functions are important for the simultaneous monitoring the instrument panel and signs in the environment. From the very beginning of the development of aviation, visual function has been deemed particularly important. The effect of +Gz acceleration on the organ of vision is very significant for investigations in aviation medicine. Visual functions are the most important of all sensory functions where flight safety and quality of flight performance are concerned. High acceleration onset rates may cause changes in pupil diameter of a pilot with significant changes in visual function. However, it is important to maintain visual functions due to rapid pilotʼs orientation in the space. The aim of this study was to establish whether there was any pupillary response in Air Force and Air Defence pilots or changes in pupil diameter when exposed to +Gz acceleration in the human centrifuge. Меthods. The study was conducted on 65 Air Force and Air Defence pilots aged from 28 to 45 years of age. The pilots were exposed to an acceleration of +5.5Gz to +7Gz. We examined the obtained differences in pupil diameter according to a rate of acceleration in the period of three consecutive days. Rеsults. Changes in pupil diameter during the pilot’s exposure to different high values of acceleration in the course of three days, measured before, during and after the exposure, generated statistically significant results. No statistically significant differences in pupil diameter were noticed when the pilots were exposed to the same values of acceleration before the testing on the first, second or third day. During the test, pupil diameter was statistically significantly larger than before the test. Conclusion. Transient changes in pupil diameter occurred in pilots exposed to a +7Gz acceleration. Pilots were able to withstand exposure to a +5.5Gz acceleration, without any major changes in the pupil diameter. Physiological training of pilots in the human centrifuge mimicking conditions of real G acceleration, improves tolerance to acceleration, which is important for flight safety.

Keywords

• acceleration
• aerospace medicine
• centrifugation
• pilots
• reflex, pupillary
• vision, ocular
• vision tests