title: Crewmember interactions during a Mir space station simulation.
abstract: BACKGROUND
  Interpersonal problems may negatively affect crews on long-duration space missions. These problems stem from crewmember tension and its displacement to the outside monitoring personnel and from disruptions in crew cohesion and unclear leadership roles.
  
  
  OBJECTIVE
  We hypothesized that crew tension and dysphoria would transiently increase following stressful events and be greater in the second half of a mission; that cohesion would be less during the second half of a mission; that tension and dysphoria would be displaced to the outside monitoring personnel; and that high levels of leader support and control would produce high levels of cohesion.
  
  
  METHODS
  We tested these hypotheses during a 135-d Mir space station simulation study in Moscow. At weekly intervals, the three crewmembers completed items from two group climate questionnaires, a mood questionnaire, and a log of stressful events.
  
  
  RESULTS
  Contrary to expectations, there was significantly (p < 0.05) more total mood disturbance and tension during the first 9 wks than during the subsequent 10 wks of the simulation. Although levels of cohesion remained the same over time, cohesion scores dropped at a significantly greater rate during the last third of the seclusion. There was evidence for the displacement of tension and dysphoria to the outside monitoring personnel. There were significant correlations in the predicted direction between leader support and control and crew cohesion, as well as evidence of status leveling in the mission commander.
  
  
  CONCLUSIONS
  Crewmember tension, cohesion, and leadership are important issues affecting people working in secluded environments, and they need to be studied further in space.
authors.affiliation: Department of Psychiatry, University of California, San Francisco, USA.
authors.forename: N
authors.initials: N
authors.lastname: Kanas
authors.forename: D S
authors.initials: DS
authors.lastname: Weiss
authors.forename: C R
authors.initials: CR
authors.lastname: Marmar
mesh_terms: D000328:Adult; D000339:Affect; D018480:Astronauts / Q000523:psychology*; D004208:Displacement, Psychological; D006126:Group Processes; D006801:Humans; D007398:Interpersonal Relations; D007857:Leadership; D008297:Male; D011237:Predictive Value of Tests; D012380:Role; D018561:Space Simulation / Q000523:psychology*; D018531:Spacecraft; D013315:Stress, Psychological / Q000523:psychology*; D011795:Surveys and Questionnaires