(PS3-7) Disordering Disorders: The Dynamics of Change and Psychotherapy Outcomes in Exposure-based Cognitive Therapy for Depression

Background: Mental health disorders can be conceptualized as self-organized patterns that emerge from the complex dynamic interactions between psychological, biological, and social elements. The properties that characterize self-organizing systems have been studied in the interdisciplinary field of complexity science. This work suggests that a period of destabilization in system dynamics—critical fluctuations—often occurs before a period of change. A small but growing literature has linked periods of destabilization in longitudinal psychological measurements to improved treatment outcomes across a range of psychopathology. However, little is known about the dynamics of destabilization that emerge during treatment, nor how the specific timing of destabilization in treatment relates to outcomes.

Objectives: Examine patient psychological system dynamics throughout exposure-based cognitive therapy (EBCT) for depression from a complexity perspective. This study focuses on the relationship between destabilization levels across the three phases of EBCT (stress management, exposure and processing, and positive growth) and treatment outcomes. Destabilization during the exposure phase was hypothesized to be associated with lower depression scores at post-treatment.

Methods: An observational coding system was used to code the content of weekly treatment narrative essays from 73 participants diagnosed with depression, who participated in two open trials of EBCT. Essays were coded for levels of positive and negative functioning in emotion, behavior, and cognitive domains. Ratings were used to construct state space grids to represent trajectories through treatment and calculate levels of destabilization by treatment phase. Phase-wise destabilization scores were entered into Bayesian multiple regression models to examine them as predictors of depressive symptoms at post-treatment.

Results: Although there were no robust differences in destabilization between phases of EBCT, only destabilization during the exposure-focused phase predicted lower depressive symptoms at post-treatment.

Conclusion: This study suggests a link between destabilization during the exposure phase of EBCT and treatment outcomes, providing some support for the utility of exposure in depression treatment. We also highlight methodological considerations for future critical fluctuation research in psychotherapy.