Review of Study Published in The Journal of Personality Disorders
Borderline Personality Disorder is typically associated with deficits related to affect regulation, impulse control, interpersonal relationships, and self-identity. Previous research also indicates that patients with Borderline Personality Disorder typically show several neuropsychological impairments that are related to right-hemisphere dysfunction. This impairment is most often observed in the case of impulse control, attention, and decision-making. According to past etiological models, these neuropsychological impairments can act as a moderator in the development of Borderline Personality Disorder. Previous studies speculate that the dysfunctional cognitive processes may play an important role in the development of mental distortions that are commonly associated with the disorder. However, previous research has yet to determine the exact pattern of these neuropsychological deficits, and examine their severity in comparison with other personality disorders. The purpose of this study was to compare the severity of neuropsychological dysfunction in patients with Borderline Personality Disorder to patients diagnosed with other personality disorders, and a healthy control group.
The authors of this study tested two main hypotheses based on the empirical findings of previous research on personality disorders. The first hypothesis was that patients with Borderline Personality Disorder will show more prominent neuropsychological deficiency than patients with other personality disorders. The second hypothesis predicted that the observed neuropsychological deficits would be most related to impulsivity.
Neuropsychological performance was measured using the Repeatable Brief Assessment of Neuropsychological Status (RBANS) test battery. The RBANS was originally created to provide comprehensive evaluations in studies designed to evaluate the efficacy of therapeutic practices. It consists of ten subtests that form five distinct index scores of immediate memory, delayed memory, language, visuo-spatial cognition, and attention. The data collected from neuropsychological assessment were correlated with specific symptoms of Borderline Personality Disorder using the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD). The ZAN-BPD defines four clinical dimensions of Borderline Personality Disorder and yields four separate scores for affective, cognitive, impulsivity, and interpersonal sectors.
The results of this study showed a clear neuropsychological impairment in the Borderline Personality Disorder group compared with the healthy control group. Post hoc tests indicated that these patients differed from the control group in domains of attention, immediate memory, and delayed memory. The neuropsychological deficit was less noticeable in subjects with other personality disorders relative to the control group. Several correlations were also found between RBANS scores and ZAN-BPD impulsivity scores.
This research suggests that attention, immediate memory, and delayed memory are the most severely impaired neuropsychological realms associated with personality disorders. The results further suggest that the neuropsychological impairments observed in Borderline Personality Disorder may be related specifically to frontal and temporal lobe dysfunctions. The frontal and temporal lobe profiles of the observed impairments also indicate that they are associated with impulsivity.
One limitation of this study was the fact that the patient groups were treated with psychotropic medications prior to testing. These medications could potentially affect cognitive performance as compared to the non-medicated control group. Another limitation of this study is that its correlational design indicates an inability to draw causal conclusions. The relationship between symptomology, etiology, and neuropsychology must be further studied in order to better understand the direct contribution of each variable on Borderline Personality Disorder features.
This study has several implications for future research. While current models such as Dialectic Behavior Therapy have moderate records of success in the treatment of Borderline Personality Disorder, there is still much that remains a mystery about the etiology and symptomology of personality disorders in general. This is a great example of the kind of research that will be necessary in order to better understand the origins and complex clinical presentations of these disorders.