Introduction: Reports from astronauts and cosmonauts, studies from space analogue environments on Earth, and our previous research on the Mir Space Station have identified a number of psychosocial issues that can lead to problems during long-duration space missions. Three of these issues (time effects, displacement, leader role) were studied during a series of long-duration missions to the International Space Station (ISS).
Methods: As in our previous Mir study, mood and group climate questions from the Profile of Mood States or POMS, the Group Environment Scale or GES, and the Work Environment Scale or WES were completed weekly by 17 ISS crewmembers (15 men, 2 women) in space and 128 American and Russian personnel in mission control.
Results: The results did not support the presence of decrements in mood and group cohesion during the 2nd half of the missions or in any specific quarter. The results did support the predicted displacement of negative feelings to outside supervisors in both crew and mission control subjects on all six questionnaire subscales tested. Crewmembers related cohesion in their group to the support role of their commander. For mission control personnel, greater cohesion was linked to the support role as well as to the task role of their leader.
Discussion: The findings from our previous study on the Mir Space Station were essentially replicated on board the ISS. The findings suggest a number of countermeasures for future on-orbit missions, some of which may not be relevant for expeditionary missions (e.g., to Mars).