EN
Extended spaceflight represents a potent psychosocial stressor. As the crew selection criteria have been sharpened over the years of experience, the effects of stressful conditions are rather subtle. Moreover, the crew members tend to deny their real feelings. For that reason it seems necessary to employ some measures of indirect assessment of possible strain to minimize the psychosocial costs of the flight. The purpose of the present study was to detect early signs of potential emotional tensions during simulated extended space mission. Three healthy male volunteers (aged 32, 36, 37) participated in the experiment designed to simulate 135 days of orbital station settings. Ambulatory recordings of physiological parameters, videotapes of crew behavior and audiotapes of the crew - control center communication were analyzed. From the results there follows an increasing level of psychosocial load encountered by the crew that can be documented by 1) increasing level of mean daily heart rate frequency, 2) increasing level of resting mean heart rate frequency, 3) increasing length of crew-control center communication and its informal part, and 4) increasing mean time spent by the subjects in bunks on leisure days.