حمیدرضا محسن زاده

Motion sickness is a natural and temporary response to unfamiliar motor stimuli which reduces performance in complex tasks that require constant attention. The aim of this research was to study the effect of a special exercise training period on motion sickness in the pilots and flight crews of the Army of the Islamic Republic of Iran.

In this study, 20 pilot students of Shahid Sattari Army Air Force of the Islamic Republic of Iran with an average (age of 21.10±1.31 years, weight of 70.27±8.23 kg, height of 173.32±5.77 cm) participated voluntarily. After completing the motion sickness questionnaire and based on the average age and scores of the rain seat test, they were divided into two equal training and control groups (n=10). The training group performed exercise training for four weeks (four sessions per week). The post-test was done after 72 hours from the last training session. The data were analyzed using SPSS version 24 software in two descriptive and inferential sections at a significant level (P<0.05).

After four weeks of exercise intervention, the intragroup results showed a significant increase in the motion sickness tolerance variable only in the training group (P=0.001). Also, the intergroup results showed a significant difference between both training and control groups in the post-test (P=0.037).

According to the results, the special exercise training can cause a significant increase in motion sickness tolerance in pilots; by stimulating the visual-vestibular and vestibular systems. Therefore, based on these findings, it is recommended that the pilots who experience symptoms of motion sickness while flying, help to improve the current conditions by performing the suggested exercise interventions.

 The pilot has a continuous flow of various activities that require navigation, attention, and navigation working memory. Fighter pilots are more vulnerable to cognitive impairment due to positive gravitational acceleration. This point indicates the importance of their cognitive assessments.

 This study aimed to evaluate visual-spatial cognitive function and attention in the pilots of the Airforce of the Islamic Republic of Iran and compare these factors between fighter pilots and other aviation personnel.

 An analytic observational cross-sectional study was performed on 49 fighter pilots (group 1) and other aviation personnel (group 2). A list of demographic variables and flight histories was recorded. Then Addenbrooke's Cognitive Examination-Revised, Rey– Osterrieth complex figure test, Forward and Backward Digit Span (FDS and BDS), and Brief Visual-spatial Memory Test-Revised were token. Data were analyzed by SPSS 18 (P <0.05).

 Both groups were homogeneous regarding age, sex, education, military-grade, flight history, and complaints of cognitive symptoms. The scores of the tests were not statistically significant between the two groups. More than 10 years of flight history and equal or less than 10 years of flight history were respectively related to higher and lower scores in BDS and “recalling words”. The scores of FDS were higher in those with equal or less than 400 hours of flight history. The scores of “delayed recalling” were higher in people with more than 400 hours of flight history and those with more than 40 hours of flight history in the last 6 months.
Discussion and

 There was no difference in visual-spatial function and attention between fighter pilots and other aviation personnel, but flight history was related to the scores of some cognitive subtests.

Hypoxia is a potential danger for aviation affairs and the lack of attention to it causes both human and financial costs. One of the main effects of hypoxia is reduction in mental efficiency. Therefore, the purpose of this study was to investigate the effects of hypoxia on hypoxic psychological aspects (selective attention and reaction time) among pilots as well as changes in heart rate and blood oxygen levels in the flight simulator of an altitude chamber.

Totally, 53 pilots referred to the altitude chamber at the air physiology center of IRAF were randomly entered the study within 10 months. Initially, the study protocol was described to them. A percentage of arterial oxygen saturation and heart rate and Stroop computer task under normal condition (class) were recorded. Then, in the hypoxic conditions (height 25000 feet) the same items were checked, recorded, and finally analyzed statistically.

The results of this study showed that hypoxia increases the reaction time and heart rate in the pilots. Also, it reduced pilots' selective attention and blood oxygen levels. All of the mentioned items were statistically significant.

Hypoxia can prolong the response time in the pilots and also disturbs their selective attention and increases the risk of accidents. The importance of this issue in fighter aircraft, which is controlled by one or two pilots, can be much more than in a cargo aircraft. Therefore, hypoxia training in the altitude chamber and attention to its psychological aspects can play an important role in correct and on time recognition of the hypoxia and safety of flights

Hypoxia is one of the major threats to human health in high altitude. Considering the importance of hypoxia experience by military pilots and educating them how to deal with this condition, this study was designed to assess the applicability of King-Devick (K-D) test in early recognition of cognitive impairments due to induced hypoxia.
Totally, 60 military pilots who were candidate to experience hypoxia in hypobaric chamber were randomly enrolled the study. Study process included the following steps: training, filling the questionnaire, K-D test in normoxic condition, denitrogenation, preparation for hypoxia, Eustachian tube performance test, simulating 25,000 ft altitude, K-D test in hypoxic condition, reusing oxygen mask.
The mean age of candidates was 31.78±7.74 years. About 46.7% of them had normal weight and 53.3% were overweight and 31.7% were smokers. The average flight time was 1168.35±1345.21 hours. The average K-D time in normoxic condition was 45.54±5.43 seconds and 71.7% of pilots had no mistake in reading numbers. The mean K-D time in hypoxic condition was 52.98±5.86 and 98.3% of pilots made 1 to 11 mistakes. Results show that smokers significantly had longer K-D time than non-smokers. There was no other significant difference between groups in terms of average K-D time and number of mistakes.
It seems that this study was the first one using K-D test in early recognition of cognitive impairments due to induced hypoxia in military pilots. It revealed that smoking significantly increases K-D time. Other factors like age, weight, and flight time did not show significant impact on K-D time and number of errors.