Content and structure of crew’s communicative behavior and gonadal hormone excretion during long-term chamber isolation of all-male international crew

The characteristics of psychophysiological adaptation to the simulation of the extended autonomous manned mission to Mars with limited resources and external communication were studied. The behavioral (communication with the external world) and physiological correlates of 105-day life and work in a pressurized compartment of the crew of six male subjects representing Russian and European space agencies under the conditions of sensory deprivation, confinement, monotony, and high autonomy were studied. Psychological, physiological, and biochemical (urinary cortisol and gonadal hormones) testing together with content analysis of the crew??s communication with the external world were made in parallel. The results confirmed, to a considerable extent, the preliminary hypothesis about the serious impact of stressful factors, including conflict, the significant decrease of the variety and scope of communication with the outer world, and social pressure on the verbal behavior and hormone levels in the future Martian crew. The correlation between the metabolism of the gonadal hormones and the volume, content, and creativity of the verbal human behavior during various stages of adaptation to the extended isolation in pressurized compartments has been discovered.     

An experiment with a 105-day isolation simulating some conditions of a space flight to mars: the goals, scope, and structure of the research

The article deals with the main goals, objectives, and features of a 105-day experiment simulating some conditions of a manned space flight to Mars. It contains the scope and time patterns of the research program of the 105-day experiment, as well as methodological and organizational recommendations for the preparation for a 520-day experiment based on the analysis of the results of a 105-day experiment.     

Effects of the 520-day isolation on the functional state of the cardiovascular system

The purpose of the study was to estimate the cardiovascular effects of simulated factors in a 520-day crewed mission to Mars, and to validate the diagnostic value of the ultrasonic investigation of microcirculation and endothelium-dependent dilation of the right brachial artery in six male volunteers at the age of 28 to 39 years. It appears that a 520-day isolation affected intracardiac hemodynamics and endothelium function more dramatically compared with a 105-day isolation, increasing the risk of atherosclerosis. These findings add insight into the “cost of human adaptation” to very long isolation.     

Wireless Monitoring of Changes in Crew Relations during Long-Duration Mission Simulation

Group structure and cohesion along with their changes over time play an important role in the success of missions where crew members spend prolonged periods of time under conditions of isolation and confinement. Therefore, an objective system for unobtrusive monitoring of crew cohesion and possible individual stress reactions is of high interest. For this purpose, an experimental wireless group structure (WLGS) monitoring system integrated into a mobile psychophysiological system was developed. In the presented study the WLGS module was evaluated separately in six male subjects (27–38 years old) participating in a 520-day simulated mission to Mars. Two days per week, each crew member wore a small sensor that registered the presence and distance of the sensors either worn by the other subjects or strategically placed throughout the isolation facility. The registration between two sensors was on average 91.0% in accordance. A correspondence of 95.7% with the survey video on day 475 confirmed external reliability. An integrated score of the “crew relation time index” was calculated and analyzed over time. Correlation analyses of a sociometric questionnaire (r = .35-.55, p< .05) and an ethological group approach (r = .45-.66, p < 05) provided initial evidence of the method''s validity as a measure of cohesion when taking behavioral and activity patterns into account (e.g. only including activity phases in the afternoon). This confirms our assumption that the registered amount of time spent together during free time is associated with the intensity of personal relationships.     

Human torpor: translating insights from nature into manned deep space expedition

During a long-duration manned spaceflight mission, such as flying to Mars and beyond, all crew members will spend a long period in an independent spacecraft with closed-loop bioregenerative life-support systems. Saving resources and reducing medical risks, particularly in mental heath, are key technology gaps hampering human expedition into deep space. In the 1960s, several scientists proposed that an induced state of suppressed metabolism in humans, which mimics ‘hibernation’, could be an ideal solution to cope with many issues during spaceflight. In recent years, with the introduction of specific methods, it is becoming more feasible to induce an artificial hibernation-like state (synthetic torpor) in non-hibernating species. Natural torpor is a fascinating, yet enigmatic, physiological process in which metabolic rate (MR), body core temperature (T_b) and behavioural activity are reduced to save energy during harsh seasonal conditions. It employs a complex central neural network to orchestrate a homeostatic state of hypometabolism, hypothermia and hypoactivity in response to environmental challenges. The anatomical and functional connections within the central nervous system (CNS) lie at the heart of controlling synthetic torpor. Although progress has been made, the precise mechanisms underlying the active regulation of the torpor–arousal transition, and their profound influence on neural function and behaviour, which are critical concerns for safe and reversible human torpor, remain poorly understood. In this review, we place particular emphasis on elaborating the central nervous mechanism orchestrating the torpor–arousal transition in both non-flying hibernating mammals and non-hibernating species, and aim to provide translational insights into long-duration manned spaceflight. In addition, identifying difficulties and challenges ahead will underscore important concerns in engineering synthetic torpor in humans. We believe that synthetic torpor may not be the only option for manned long-duration spaceflight, but it is the most achievable solution in the foreseeable future. Translating the available knowledge from natural torpor research will not only benefit manned spaceflight, but also many clinical settings attempting to manipulate energy metabolism and neurobehavioural functions.     

During the Long Way to Mars: Effects of 520 Days of Confinement (Mars500) on the Assessment of Affective Stimuli and Stage Alteration in Mood and Plasma Hormone Levels

For future interplanetary manned spaceflight, mental issues, as well as physiological problems, must inevitably be considered and solved. Mars500 is a high-fidelity ground simulation experiment that involved 520 days of confined isolation for six multinational crewmembers. This experiment provided a good opportunity to perform psycho-physiological and psycho-social researches on such missions. To investigate emotional responses and psychological adaptation over long-term confinement, the International Affective Pictures System (IAPS) was selected as the visual emotional stimuli in this study. Additional data collected and analyzed included the Profile of Mood States (POMS) questionnaire and the levels of four types of plasma hormones: cortisol, 5-hydroxy tryptamine, dopamine, and norepinephrine. The results demonstrated an obvious bias on valence rating for unpleasant stimuli with time (p<0.05), and the correlation between psychological and biochemical data was identified (p<0.05). Overall, we concluded that the confined crew tended to assign positive ratings to negative pictures with time, which might be driven by a defensive system. There was a stage-changing pattern of psychological adaptation of the Mars500 crew, which is similar to the third-quarter phenomenon.     

Psychophysiological issues of manned space flights

The article deals with some issues of psychophysiological support (PPS) of manned space flights discussed with Academician O.G. Gazenko. It has been shown that even at the initial stages of development of space flights (SFs), monitoring and evaluation of the mental state and working capacity of crew members were regarded as the key components of PPS and merited special comprehensive studies with the development of associated methods. The polyeffectors method for recording physiological functions, such as electrocardiogram, electroencephalogram, and skin-galvanic reaction, was recognized as a potent tool in gathering information for the assessment of the current state of health. In the period of the performance of long-term orbital flights, starting with the 96-day flight of Yu. Romanenko and G. Grechko, the system of psychological support developed at the Institute for Biomedical Problems (IBMP), under the leadership of Gazenko was introduced into PPS, and then used in all flights of the stations Salyut and Mir, and now at the International Space Station. Evidently, the use of this system made a significant contribution to the PPS and maintenance of health and working efficiency of crews.     

Human Neurophysiological State in Long-term Isolation

During 520-day isolation in a confined space as an imitation of a long-term interplanetary flight, the neurofunctional condition of six crew members was examined using synchronous recording of electrical ( electroencephalogram) and energy (constant potential level) activities of the brain. Two background studies made it possible to predict high adaptability level of all crewmembers and low probability of adaptation reserve depletion in the course of the experiment. During isolation, the dynamics of neurofunctional correlates of cerebral activity generally corresponded to factors to which the crew was subjected during its activity. During the events significant for the crew, we observed physiological reactions in both metabolic and electrical activities of the brain. During the 54th week, the state of physiological adaptation of the crew to the experimental environment was observed, which was expressed in decreases in constant potential level (CPL), without interhemispheric asymmetry, and absolute α-power value. Throughout the experiment, none of crewmembers exhibited distinct stress reaction signs (α-activity asymmetry accompanied by a significant CPL decrease), which confirmed our prediction of a low probability of adaptation reserve depletion in the participants of the 520-day isolation study.     

Problems of Distant Communication of Isolated Small Groups

A new psychological phenomenon, distant communication of an isolated small group, is described. Factors affecting distant communication and mechanisms determining the patterns of its development during a long-term spaceflight and model isolation are analyzed. On the basis of the patterns described, the possible development of communication in the spacecraft–Earth loop during a mission to Mars is predicted and methods of its optimization are suggested.     

Immunological aspects of a space flight to Mars

The effects on the immune system of a 520-day isolation in a confined environment, simulating some conditions of a manned space flight to Mars, have been studied. A set of signs of adaptational reorganization, including quantitative and functional changes in innate and adaptive immunity, have been recorded. The most significant ones include the changes in the system of Toll-like receptors (TLRs) manifested as a decrease in the content of circulating monocytes and granulocytes expressing TLR2, TLR4, and TLR6; a decrease in the functional capacity of cellular factors of natural cytotoxicity or natural killer cells (NK cells); an increased ability of T cells and B cells to express on their surface the CD69 early activation marker; and an increase in phytohaemagglutinin (PHA)-induced secretion by cytokines in peripheral blood mononuclear cells. Intense mobilization of adaptive immunity and qualitative changes of its functions demonstrates the adaptive adjustment of the body in response to the combined effect of unfavorable factors to preserve immune homeostasis.     

Individual and group adaptation in space: evidence from analogue environments

As the duration of space missions increases and crews become more heterogeneous, psychological and interpersonal factors are likely to play an increasingly important role in determining mission success. Empirical evidence about psychological factors in space has to a large extent been based on personnel in analogue environments. Studies in these environments have included effects of multi-nationality on crew interaction, gender issues, development of tension within crews and in relation to Mission Control. Results so far demonstrate the need for countermeasures designed to address psychological and interpersonal dysfunctions, specifically selection, training and in-flight support.     

Confinement and free-volume requirements

Enclosure of individuals within a limited space may give rise to problems devolving from the associated restriction or constriction, as modified by any accompanying elements of social isolation and perceptual deprivation. In this paper, the nature of the resulting problems is outlined on the basis of analysis of some 60 studies of operational and experimental human confinement in which the associated elements of isolation and perceptual deprivation were considered minimal, along with consideration of other related work. It is pointed out that in the operational situations so far encountered, and in experimental studies in which highly trained and well-motivated subjects undergo realistic space-mission simulation, undesirable psychological effects have been negligible. Physiological effects are similar to those found in actual and simulated weightlessness, and are dependent largely upon the extent of immobility and the duration of the confinement. The response to confinement, including those undesirable psychological effects which are primarily associated with the extent of social isolation and perceptual deprivation, is modified by factors within the individual, such as motivation, personal qualities, training and experience, by the quality of leadership and group compatibility, by physical fitness of the crew and the use of exercise regimens, by the suitability and habitability of the immediate environment, the suitability of work and rest schedules, the meaningfulness of the activities and tasks in which the subjects or crew are engaged, by the existence of facilities for recreation and the creative use of leisure, and by informed knowledge of the status of the mission. The requirements for free internal volume of space vehicles for long-duration (400-day) missions cannot be stated with accuracy at this time, but from examination of confinement studies and crew-activity analyses, it is suggested that the minimum free volume per man in a multi-man crew would be about 200–250 cubic feet; the acceptable would be about 350–400 cubic feet, and the optimal about 600–700 cubic feet.Supported by Contract NASr-115, Directorate of Space Medicine, Office of Manned Space Flight, National Aeronautics & Space Administration, Washington, D.C.     

Specificity of sleep-wakefulness cycle during a 105-day isolation

Six healthy volunteers aged 25 to 40 years were test subjects in a 105-day isolation experiment (the Mars-105 project). The methods of investigation included filling in structured reports on sleep and wakefulness quality and the data of polysomnography at night.     

Preventing annoyance from odors in spaceflight: a method for evaluating the sensory impact of rodent housing.

For the scientific community, the ability to fly mice under weightless conditions in space offers several advantages over the use of rats. These advantages include the option of testing a range of transgenic animals, the ability to increase the number of animals that can be flown, and reduced demands on shuttle resources (food, water, animal mass) and crew time (for water refill). Mice have been flown in animal enclosure module (AEM) hardware only once [Space Shuttle Transport System (STS)-90] and were dissected early in the mission, whereas rats have been flown in the AEM on >20 missions. This has been due, in part, to concerns that strong and annoying odors from mouse urine (vs. rat urine) will interfere with crew performance in the shuttle middeck. To screen and approve mice for flight, a method was developed to evaluate the odor containment performance of AEMs housing female C57BL/6J mice compared with AEMs housing Sprague-Dawley rats across a 21-day test period. Based on the results of this test, consensus was reached that mice could fly in the AEM hardware for up to 17 days (including prelaunch and contingency) and that the AEM hardware would likely contain odors beyond this duration. Human sensory and electronic nose analysis of the AEMs postflight demonstrated their success in containing odors from mice for the mission duration of STS-108 (13 days). Although this paper focuses specifically on odor evaluations for the space shuttle, the concern is applicable to any confined, closed-system environment for human habitation.     

Interpersonal Interaction under the Conditions of High Autonomy in Interplanetary Mission Simulation (Mars-500 Experiment)

This paper discusses the influence of the social status and psychological stability of individuals on their communicative behavior in space flight on the basis of retrospective analysis of the findings of the Mars-500 experiment, in which six participants were isolated for a period of simulating a long-term exploration mission. Data were obtained using both classic social-psychological methods and observation of video recorded behavior. Communicative behavior of the crew members was dependent on the level of individual anxiety and social status in the isolated small group.     

Radiation burdens for humans on prolonged exomagnetospheric voyages.

The severity of radiation exposure for astronauts outside the magnetosphere poses a critical unanswered question bearing on the use of manned vehicles in extended exploration of the solar system (moon, Mars). Such prolonged exomagnetospheric voyages (1-3 years) enter a radiologic environment more severe than that of low earth orbit, an annual dose equivalent in the range of 0.3-0.5 Sv (30-50 rem), and a lifetime excess cancer fatality risk of 3-5% due to low linear-energy-transfer components of galactic cosmic radiation alone. To this calculus must be added estimates for high-atomic-number, high-energy particles, the probability of solar particle events, and the limited effectiveness of shielding. For a 3-year Mars voyage these could elevate the dose equivalent to 1.5-2.25 Sv (150-225 rem) total (0.5-0.75 Sv [50-75 rem] annual) and risks to 5-9% excess cancer fatality. Both the mission (civilian scientific research) and the alternatives (unmanned robotic devices) enter the policy decision here. This paper presents a brief review of pertinent physical and biological data and of research urgently needed before reaching a decision on this question.     

关于执行护航任务舰艇官兵情绪的影响因素探讨

目的:执行护航任务过程中,有很多因素会影响舰艇官兵的情绪,出现各种不良情绪问题。本文的目的是探索究竟是哪些因素影响官兵情绪,使情绪调控更有针对性。方法:本文采取自编《护航官兵情绪调控问卷》对329名执行过不同批次护航任务的官兵进行调查分析。结果:根据问卷结果,通过对问卷进行因素分析,发现KMO值为0,934,并得出在8个因素上具有较高的载荷,分别是人际、舆论、领导、归因、管理、任务、认知和个性八种影响因素。这八种因素根据护航任务的不同阶段有不同表现,对官兵情绪产生不同程度的影响。结论:影响护航舰艇官兵情绪的因素为八种,分别是人际、舆论、领导、归因、管理、任务、认知和个性,并且这些因素对情绪产生着不同程度的影响。     

Genomics in space life sciences

Since the early days of manned spaceflight, hazardous effects of the space environment on living organisms have been disputed. With the continuous manning of the International Space Station, the planned Chinese space station, and renewed interest in returning to the Moon and sending manned flights to Mars, identifying and addressing the potential outcomes of long-term space exposures is critically important.     

Hemostasis system indices in the course of a 105-day hermo chamber isolation experiment

The present paper deals with studying of hemostasis system indices in the course of the experiment with a 105-day isolation in a hermo chamber. The following values were determined: activated partial thromboplastin time, prothrombin time (PT), prothrombin index (PI), international normalized ratio [relationship] (INR), thrombin time, fibrinogen concentration, soluble fibrin-monomer complexes, D-dimer, plasminogen (PG), activity of antithrombin III, protein C, alpha2-antiplasmin. According to the experiment results, isolation is accompanied by PT prolongation (PI decreasing, INR increasing) which conserves up to the 7th day of the aftereffect period, as well as by PG concentration decreasing. Changes are likely to be connected with peculiarities of reduced motion activity conditions, compensatory physical activity influence, protein and lipid metabolism characteristics changing.     

Attenuation of psychosocial stress-induced hypertension by gamma-linolenic acid (GLA) administration in rats

This study investigated a model of psychosocial stress-induced hypertension in the rat, and examined effects of the prostaglandin E precursor, gamma-linolenic acid (GLA) on the development of hypertension during psychosocial stress. In the first study, male rats were housed four/cage for an acclimation period of 21 days, followed by a 14-day control period. An experimental group (N = 12) was then placed in isolation cages for 14 days, then regrouped for a 7-day recovery period. Controls (N = 12) remained group-housed. Eight animals per group were sacrificed after the experimental period, and four per group after recovery for organ weight analysis. Mean systolic blood pressure (BP) was similar between groups during the control period (126 +/- 2 and 125 +/- 2 mm Hg), but increased during isolation, reaching 140 +/- 2 mm Hg (P less than 0.001) by Day 14. During recovery BP returned to control levels. No changes in heart rate, heart weight/body weight or adrenal weight were seen. The second study utilized a protocol similar to that of the experimental group of the first study, minus the recovery period. On Day 1 of the control period 28-day osmotic pumps were implanted ip, releasing olive oil or GLA in olive oil. Four groups of rats (N = 8/group) received either (i) olive oil (controls), (ii) 0.018 mg GLA/hr, (iii) 0.040 mg GLA/hr, or (iv) 0.040 mg GLA/hr with no stress. Organ weights were obtained following stress in groups 1-3. Controls developed a sustained elevation in BP within 24 hr of isolation. Animals receiving 0.018 mg GLA/hr developed elevated BP upon isolation, but the BP was less than that of controls on Days 1 (P less than 0.05) and 14 (P less than 0.001) of isolation. Animals receiving 0.040 mg GLA/hr demonstrated a greatly attenuated rise in BP vs controls (P less than 0.001) on all isolation days. GLA in unstressed rats had no effect on BP. Heart rate, heart weight/body weight, and adrenal weight were unchanged in all groups. These data suggest that (i) isolation is a useful tool for investigating reversible psychosocial stress-induced hypertension, and (ii) GLA, while not affecting BP in unstressed animals, produces a dose-dependent attenuation of the BP response to chronic stress.