Evaluation of Executive Functions With Functional Near-Infrared Spectroscopy in Euthymic Bipolar and Borderline Personality Disorders.

ABSTRACT

Introduction: Bipolar disorder (BD) and borderline personality disorder (BPD) are often indistinguishable, given both the key features of impulsivity and emotional dysregulation. This indicates widespread comorbidity and potential misdiagnosis in both groups. Therefore, this study aimed to differentiate BD and BPD by using alterations of brain hemodynamics under the influence of executive tests. Methods: Twenty patients with the euthymic phase of BD and 20 patients with BPD, and 20 healthy control subjects were included in this study. The prefrontal cortex (PFC) hemodynamic responses were evaluated using functional near-infrared spectroscopy (fNIRS) during the Stroop Test and Wisconsin Card Sorting Test (WCST). Results: Left dorsolateral prefrontal cortex (DLPFC) activation was significantly decreased in BPD during both tests. On the other hand, the BD group showed medial PFC hypoactivation during both tests, and this finding is distinct from BPD (p<0.05). Conclusion: Our results indicate that brain hemodynamics during the executive test can highlight differences between BP and BPD. While medial PFC hypoactivation was more prominent in the BP group, DLPFC hypoactivation was more pronounced in the BPD group.