Over four decades of cognitive complexity research demonstrate that higher integrative complexity (measured by the ability to differentiate and integrate multiple dimensions or perspectives on an issue) predicts more lasting, peaceful solutions to conflict. Interventions that seek to raise integrative complexity offer a promising approach to preventing various forms of intergroup conflict (e.g. sectarianism, violent extremism). However, these contexts can also be extremely stressful, and dominant theory suggests that cognitive complexity diminishes in the face of high stress. However, we know that this is not always the case, with some findings demonstrating the opposite pattern: increases in complexity under high stress. How is it that some people in the midst of stressful conflict are able to recognize multiple perspectives and solutions, while others become increasingly narrow and rigid in their thinking? The aim of this paper is to integrate these divergent findings through the broader framework of the biopsychosocial model of stress and to explore possible underlying mechanisms such as affect. Implications for intervention will also be discussed
