Relational Fractal Dimension: From the Complexity of Psychological Interview to the Emergence of the Therapeutic Relationship.

The psychological interview is a complex system which emerges from the interaction of its components, i.e., the patient and the psychologist; therefore, it is presumed to display a fractal structure whose dimension defines its level of complexity. This paper presents a pilot study for a new evaluative methodology of the fractal dimension in the psychological interview: the analysis of 4 psychological interviews led to the determination of their fractal dimension, defined by the amount of verbal content produced. The conversational turn-taking naturally established in the patient-psychologist dyad divides the verbatim transcripts of the sessions into Relational Verbal Units (RVU), whose sizes are determined by the number of words which composes them. It was observed that the distribution of the RVUs in a size/frequency graph follows a power law distribution, from which it was possible to assess the Relational Fractal Dimension (RFD) of the interviews. The values obtained range from a minimum of 1.39 to a maximum of 1.50, an indicative range of self-organized criticality. Recursion is the simple process behind complexity, and it defines fractal patterns; the fractal dimension of a system characterizes its level of complexity, and its application in psychotherapy describes the therapeutic relationship as a nonlinear dynamic system endowed with self-organization and self-similarity.