Depression – a Complex Dynamic System

Abstract

This article focuses on some new developments in the treatment of Major Depressive Disorder with the question of how to optimize psychotherapeutic procedures. Following the intention of the editor of this journal, a short synopsis is given on the scientific and practical developments at the Institute of Synergetics and Psychotherapy Research at the Paracelsus Medical University Salzburg. One focus is on the personalization of psychotherapy, which concerns new methods of case formulation (e.g., Idiographic System Modelling and computer-based tools for its visualization) and technologies for high-frequency process-monitoring and -feedback. For this reason, we developed and validated the Synergetic Navigation System (SNS) which is an Internetand App-based application for data collection, data analysis, and visualization of change dynamics and outcome. Based on this methodology, it became evident that the psychotherapeutic processes of depressive disorders are characterized by discontinuous patterns, so called «order transitions». The precursors of these discontinuous transitions are critical fluctuations represented by increased dynamic complexity, and an increase in the synchronization of the inter-item dynamics of the therapy process questionnaire. The amount of critical instabilities occurring before order transitions revealed to be predictive for treatment outcome. Beside clinical improvement also neural connectivity patterns are changing by psychotherapy, as could be shown in repeated fMRI scans during inpatient treatment of comorbid depressive patients with obsessive compulsive disorder. The functional connectivity dynamics of 119 brain regions was assessed during the resting state periods of the repeated scans, showing that neural rigidity (a loss of flexibility and fluidity) is associated with psychopathology (e.g., depression, BDI), but flexibility increases during psychotherapy. Finally, the option of combining psychotherapy with noninvasive neurostimulation will be discussed.