The Neuropsychological Mechanisms of Treatment of Bipolar Disorder and Borderline Personality Disorder

Objective: To explore the alteration of brain regions after treatments for bipolar disorder (BD) and borderline personality disorder (BPD) in order to discover the underlying neural mechanisms of therapies.Data Sources: An electronic search of the PubMed, Embase, Cochrane Library, and Web of Science databases from inception until June 2021 was conducted.Study Selection: Articles reporting the results of changes in brain activation after treatment, to assess the effects of therapy relative to a before-treatment condition, were included. A total of 1,592 records were retrieved, with 34 studies ultimately included.Data Extraction: Activation coordinates were extracted from each study. We used activation likelihood estimation meta-analysis to evaluate the similarities and differences in the activation of different brain regions in patients with BD and BPD after treatment with psychotherapy and drug therapy.Results: Most brain regions with abnormal activation were improved after treatments for BD and BPD. The brain activity changes produced by psychotherapy were mostly in the frontal areas, while drug therapy primarily impacted the limbic areas. In BD, treatments were associated with activation alterations in the inferior frontal gyrus, superior temporal gyrus, and cingulate gyrus, while in BPD, treatments were associated with activation alterations in the supramarginal gyrus, middle frontal gyrus, and parahippocampal gyrus.Conclusions: These results suggest that drug therapy might have a bottom-up effect, while psychotherapy might have a top-down effect. This study may contribute to the clinical prediction of treatment efficacy in BD and BPD and to the identification of more accurate neuroimaging biomarkers for treatment of the two disorders.