Mapping Psychological (In)Flexibility in U.S. Military Veterans: A Directed Acyclic Graph Approach to the Hexaflex Model

The Hexaflex model, a core theoretical framework of Acceptance and Commitment Therapy, comprises six components that foster psychological flexibility – present-moment awareness, defusion, self-as-context, acceptance, contact with values, and committed action – each with an opposing factor which is indicative of more inflexible responses. Previous research has examined unique associations among these variables using a complex systems approach. However, it remains unclear how patterns of activation unfold within these systems for military veterans. Using Directed Acyclic Graphs in a sample of U.S. military veterans (N=283), the current study aimed to identify potential pathways between key components of the Hexaflex model in a sample at risk for developing mental health complaints. We conducted separate analyses for components of flexibility and inflexibility. The Directed Acyclic Graphs highlight committed action and acceptance as central drivers of psychological flexibility, while cognitive fusion appears to initiate cascades of inflexibility through self-as-content and inaction, ultimately contributing to experiential avoidance, diminished present-moment awareness, and lack of contact with values. Although based on cross-sectional data, these findings shed light on possible pathways towards psychological flexibility and inflexibility, with immediate theoretical and clinical implications.