Neural responses to emotional stimuli in comorbid borderline personality disorder and bipolar depression

Borderline personality disorder (BPD) is a severe clinical condition characterised by different maladaptive traits such as impulsivity and affective lability. Mood and emotion dysregulation are core features of affective disorders. Indeed patients affected by mood disorder (MD) have a significantly higher prevalence of comorbid BPD, resulting in more unstable mood and poorer response to medication. Blood oxygen level-dependent functional magnetic resonance imaging has been used to investigate the neural correlates of emotional face processing. Images for each subject were entered into an analysis of variance (ANOVA) dividing participants into three groups (MD, MD+BPD, Controls). MD+BPD patients show lower activations in the dorsolateral prefrontal cortex and higher activations in the cingulate cortex and hippocampus. The present study identifies the neural basis of the interaction between BPD and MD. The lower rate of response to treatment in MD+BPD could be related to a more severe emotional dysregulation syndrome.