Neural correlates of psychotherapy in mental disorders: A meta-analysis of longitudinal resting-state fMRI studies

Background: Psychotherapy is a crucial approach in the treatment of mental disorders. However, how psychotherapy modulate spontaneous brain activity and finally take therapeutic effects remain unknown. Among countless number of analytic methods of resting-state functional magnetic resonance imaging (rs-fMRI), Regional Homogeneity (ReHo), Degree Centrality (DC), and Amplitude of Low Frequency Fluctuation (ALFF), are commonly used voxel-wise whole-brain (VWWB) metrics, and these studies could be used for coordinate-based meta-analysis. In order to reveal the underlying neural mechanisms of psychotherapy in patients with mental disorders, serving for future precise targeting intervention, we conducted a systematic review and meta-analysis based on rs-fMRI studies at VWWB level. Material and methods: A systematic literature search was conducted in PubMed, PsycINFO, and Web of Science following PRISMA criteria (registration number CRD42023432388) to investigate the differences between preand post-psychotherapy. To investigate whether changes in spontaneous brain activity differ across different metrics, distinct psychotherapy approaches or specific patient populations, subgroup analyses were performed. Results: Nine studies involving a total of 192 patients were included. We observed a significant decrease in spontaneous activity within the left insular after treatment with psychotherapy. Moreover, the subgroup analysis revealed significantly decreased ReHo in the right inferior frontal gyrus. Conclusions: The current study indicates that the clinical efficacy of psychotherapy may be modulated by insular and right inferior frontal gyrus through neurological perspective. This contributes to our understanding of the neurobiological mechanisms of psychotherapy and provides valuable insights into improving precise targeting interventions for individuals with mental disorders.