Interrelations between the small isolated groups with homogeneous and heterogeneous composition.

Increase in the heterogeneity of a space crew's composition (cultural and gender differences) is a risk factor that can negatively influence the formation of a cohesive crew, which depends on a common way of perceiving one's social environment, goals and values. Method. Three groups working in isolation from 110 to 240 days, all with different cultural and gender composition were analysed using a modification of Kelly's repertory grid technique during a space simulation at the Institute for Biomedical Problems, Moscow. Subjects assessed themselves and each other monthly. Results. National Russian and international groups failed to create a single cohesive crew. Members of both groups considered people from their group as "us" and their neighbours as "them". Their relations became more negative during the mission, with attitudes changing from neutral to poor. Subjects began to perceive each other as "different and distant". Cultural and language differences prevented national (Russian) and international groups from forming a common understanding of behavioural rules and establishing close emotional contacts. Conclusions. Differences in perception of the interpersonal environment, group goals and values in national and international groups hindered the formation of a joint cohesive crew.