Effects of pharmacological treatments on emotional tasks in borderline personality disorder: A review of functional magnetic resonance imaging studies

Background: Borderline personality disorder (BPD) is a common mental disorder characterized by instability in interpersonal relationships, impaired self-image, impulsivity and aggressive behaviors that often requires pharmacological treatments. Neuroimaging alterations have been extensively reported in BPD, especially in regions within the fronto-limbic system. Although medications can be an important confounding factor in functional Magnetic Resonance Imaging (fMRI) studies, their role on brain function in BPD patients still remains uncertain. Therefore, this review aims to improve our understanding on the potential effect of the most commonly prescribed drugs for BPD on brain function during processing of emotional tasks. Methods: A search on PubMed, Scopus and Web of Science of fMRI studies exploring the effect of antipsychotics, antidepressants and mood stabilizers on brain activity during processing of emotional tasks on BPD was conducted. Results: Overall the studies showed small or no effect of pharmacological treatments on brain activity and connectivity in BPD patients during processing of emotional tasks. Limitations: The small sample size, the observational design, the elevated percentage of women, the concomitant use of psychostimulants, anticholinergics and opioids substitute treatments and the high rate of comorbidities limit the conclusion of this review. Conclusions: Pharmacological treatments seem to have minor role on brain activity/connectivity in BPD patients during emotional tasks, ultimately suggesting that in BPD patients brain deficits seem not be influenced by medications. This might be due to functional brain specificities of BPD and to the differences in pharmacological regimens and compliance to therapy between BPD and other common psychiatric disorders.