Emotional changes and outcomes in psychotherapy: A systematic review and meta-analysis.

Objective: This systematic review and meta-analysis summarize current knowledge on emotional change processes and mechanisms and their relationship with outcomes in psychotherapy.

Method: We reviewed the main change processes and mechanisms in the literature and conducted meta-analyses of process/mechanism-outcome associations whenever methodologically feasible.

Results: A total of 121 studies, based on 92 unique samples, met criteria for inclusion. Of these, 85 studies could be subjected to meta-analysis. The emotional change processes and mechanisms most robustly related to improvement were fear habituation across sessions in exposure-based treatment of anxiety disorders (r = .38), experiencing in psychotherapy for depression (r = .44), and emotion regulation in psychotherapies for patients with various anxiety disorders (r = .37). Common methodological problems were that studies often did not ascertain representative estimates of the processes under investigation, determine if changes in processes and mechanisms temporally preceded outcomes, disentangle effects at the within- and between-client levels, or assess contributions of therapists and clients to a given process.

Conclusions: The present study has identified a number of emotional processes and mechanisms associated with outcome in psychotherapy, most notably fear habituation, emotion regulation, and experiencing. A common denominator between these appears to be the habitual reorganization of maladaptive emotional perception. We view this as a central pan-theoretical change mechanism, the essence of which appears to be increased differentiation between external triggers and one's own affective responses, which facilitates tolerance for affective arousals and leads to improved capacity for adaptive meaning-making in emotion-eliciting situations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).