Mechanisms of Action in Psychotherapy

Therapy at its core is based on learning, and learning at its core is biological. Experience that is not in some way encoded in the brain and/or body is lost. This chapter provides a discussion of mechanisms of therapy research in PTSD in which the goal is to understand how PTSD therapy works. First, the chapter reviews what a mechanism is and how therapeutic mechanisms are examined. It then discusses the importance of therapeutic mechanisms research within the broader realm of mental health research. It focuses on prolonged exposure (PE) therapy for PTSD as an example of application of mechanisms research methodology and begins with the presentation of a theoretical model that builds on previous theory and mechanisms research to date. While much of this model is theoretical, the goal is to show how mechanisms research may apply to clinical practice to improve precision, efficiency, and efficacy.