Determining the psychophysiological responses of military aircrew when exposed to acute disorientation stimuli

Abstract

IntroductionExposure to enviromental flight conditions may impair performance and physical integrity, thus training in simulated environments it is a key factor. This research aimed to study the psychophysiological response, cortical arousal and autonomic modulation of pilots and medical aircrew personnel during disorientation exposure, considering gender, experience, flying hours and body mass index (BMI) as influencial variables.MethodsA total of 47 soldiers (37 men and 10 women, 22 medical aircrew personnel and 25 fighter pilots) of Spanish Air Forces faced 25 min of vestibular, proprioceptive and visual disorientation.ResultsDisorientation exposure elicited an increased psychophysiological response, significant increases in isometric hand strength, cortical arousal, autonomic modulation, perceived stress and effort in both groups while a significant decrease in respiratory muscle capacity and blood oxygen saturation in the medical aircrew group were found. Cross-sectional analysis showed gender differences, males presented greater parasympathetic activity and strength. Larger BMI was associated with greater levels and perception of stress as well as lower cardiovascular performance and sympathetic modulation. Furthermore, experience, previous training and larger flying hours correlated with greater parasympathetic modulation.ConclusionDisorientation exposure produces an increase in cortical arousal and decrease in the parasympathetic nervous system either in pilots and medical aircrew personnel. In addition, medical aircrew personnel are less adapted to disorientation stimulus presenting significantly higher psychophysiological stress response, thus complementary physical training should be mandatory.

Impact of Real and Simulated Flights on Psychophysiological Response of Military Pilots

“…Hypothetically, these results could also be explained since all the analysed pilots were expert. A previous study reinforces this explanation since lower HRV values were related to a lower level of experience [ 20 ]. Authors explained that this could be an adaptive response to this stressful environment [ 20 ].…”

“…A previous study reinforces this explanation since lower HRV values were related to a lower level of experience [20]. Authors explained that this could be an adaptive response to this stressful environment [20]. Another study showed that a pilot's first flight was the most stressful [7,39].…”

“…Autonomic modulation analysis was used in a military population as a stress marker, showing how different military manoeuvres, independently of land or flight units, produced an increased sympathetic modulation [18]. Moreover, the fatigue induced by flights can also be detected by spirometry, handgrip strength, and stress and exertion rates as previous authors showed in this special population [19][20][21][22].…”

Portable Biosensors for Psychophysiological Stress Monitoring of a Helicopter Crew

“…The large demand of the intervention, the lack of control, and the uncertainty produce the increase in the stress response through the increase in sympathetic modulation, affecting performance, reducing cardiopulmonary capacity and strength, and momentarily stopping the urine and intestinal processes in order to prioritize organic resources to maintain survival [1,3,7,10,11,14,29]. Specifically in the low-altitude flight, we found an increased anxiety response, probably related with the danger of the maneuver, since it was conducted at a low altitude, and any minimal failure could finish in a mortal accident; nevertheless, during the flight, the sympathetic modulation decreased, showing the habituation expected from highly trained subjects [16]. This response is in line with results obtained in armies and militaries in different combat maneuvers (asymmetrical, symmetrical, urban combat, etc.…”

“…Military air operations are considered some of the most stressful events in the military, but most previous aircrew research in this area has been carried out on special tactical groups, such as paratroopers, showing how the exposure to these extreme environments and types of jumps produced a decrease in cortical arousal and an increase in the physiological stress response, mediated by the autonomous sympathetic system [8][9][10][11]. In particular, aircrews are susceptible to suffering a large variety of critical situations, since they are exposed to stressors such as hypoxia, disorientation, G forces, accidents, or air attacks during their interventions, and have to face different demands, such as different types of parachute jumps, nocturnal jumps, ground training in war zones, and different types of flights at different heights-HALO (high altitude low opening) and HAHO (high altitude high opening)-as well as underwater training in case of aircraft accidents between others [6][7][8][9][10][11][12][13][14][15][16][17][18].…”