Idiographic and nomothetic relationships between momentary interpersonal behaviors, interpersonal complementarity, and alliance ruptures in psychotherapy.

In this study, we aimed to examine how moment-to-moment interpersonal behaviors of warmth and dominance in patients and therapists, as well as interpersonal complementarity, are related to withdrawal and confrontation ruptures as sessions unfold. Sixteen psychotherapy sessions from eight independent therapeutic dyads were sampled for the highest level of alliance ruptures from a naturalistic psychotherapy data set featuring evidence-based psychodynamic psychotherapy for patients with interpersonal problems and personality pathology. Interpersonal behaviors, complementarity, and alliance ruptures were generated every 30 s within each session. Subgrouping within group iterative multiple model estimation (S-GIMME) was used to identify an idiographic network structure for each session and examine generalizability at the nomothetic and subgroup levels. Nomothetically, patients' dominance negatively predicted therapists' dominance concurrently, but positively predicted therapists' dominance with a 30-s lag; additionally, therapists' dominance predicted their own concurrent warmth. At the subgroup level, therapists being less dominant than typical predicted more concurrent withdrawal ruptures. Idiographic modeling revealed a high degree of heterogeneity in how interpersonal behaviors are associated with ruptures. More confrontation ruptures concurrently predicted higher dominance complementarity in one subgroup. This study demonstrated the interconnection between patients' and therapists' in-session behaviors as well as the role of therapists' behaviors in momentary rupture development. This study highlights the importance of attuning and responding to individualized, momentary therapeutic contexts in navigating ruptures, and emphasizes the value of idiographic relational network approaches to aid in psychotherapy research and case conceptualization. (PsycInfo Database Record (c) 2022 APA, all rights reserved).