Membership change and group cognitive complexity: the moderating role of normative interventions.

In this experimental study, we tested main and interaction effects of membership change and normative interventions aimed at increasing collaboration and participation on cognitive decline in groups. Three hundred participants were randomly assigned in one of the four types of groups (N = 75), based on crossing the independent variables, each with two conditions: membership change (most active member vs. least active member leaves the group) and normative interventions for achieving consensus (presence vs. absence of normative interventions). The results show that normative interventions reduce cognitive decline evaluated as the decrease in groups' cognitive complexity, with groups that received normative interventions actually having a cognitive gain. Membership change did not have a significant effect on cognitive decline. In addition, results show that normative interventions attenuate the cognitive decline in the case of most active member's departure. The results have important implications for group adaptation after membership loss. [ABSTRACT FROM AUTHOR]