Oxytocin as a Biomarker of the Formation of Therapeutic Alliance in Psychotherapy and Counseling Psychology.

The therapeutic alliance is one of the most consistent predictors of therapeutic change, including symptom reduction and improvement in wellbeing and quality of life, across a variety of mental health interventions. Yet, little is known about its biological mechanisms. Oxytocin (OT) has been suggested as a biological mechanism by which bonds are formed and strengthened across species. This article is intended to demonstrate the potential of OT as a biomarker of therapeutic change in psychotherapy and counseling psychology, especially of the therapeutic alliance. We delineate three main potential paths of investigation based on the most recent research on OT in parent–child and romantic partner dyads. For each path, we provide a detailed explanation for whom, when, and how OT should be measured. Each path is illustrated using data collected in a randomized controlled trial of psychotherapy for major depressive disorder. These illustrations demonstrate the great potential of OT as a biomarker of (a) trait-like characteristics of the patients and the therapists, (b) the processes of therapeutic change, and (c) the dyadic synchrony between patients and their therapists. The potential clinical contribution of OT as a biomarker for each of these three paths is further demonstrated using a case study. Practical suggestions and directions for future research are discussed. Public Significance Statement: The article highlights the promising potential of OT as a biomarker in psychotherapy research, through the most recent research on the role of OT in parent–child and romantic relationships, as well as through data from a randomized controlled trial of psychotherapy for major depressive disorder. The article provides practical suggestions on how this potential may be realized. Interdisciplinary studies integrating the two fields of inquiry, psychotherapy and OT research, can create new important knowledge that has the potential to make a substantial contribution to clinical practice and complement existing approaches for measuring the process of therapeutic change. [ABSTRACT FROM AUTHOR]