Loudness dependence of auditory evoked potentials in patients with borderline personality disorder--impact of psychopathology.

Alterations of the central serotonergic system are considered to be involved in the pathophysiology of borderline personality disorder (BPD). The loudness dependence of the N1/P2 component of auditory evoked potentials (LD) has been shown to indirectly reflect central serotonergic activity. The aim of this study was to investigate LD in patients with BPD compared to healthy controls, and to evaluate the association between LD and psychopathology such as anxiety, anger or impulsiveness. Female patients with BPD were included and compared to age- and sex-matched healthy subjects. Self-rating instruments, such as the State-Trait Anxiety Inventory (STAI), State-Trait Anger Expression Inventory (STAXI), and the Barratt Impulsiveness Scale (BIS) were used to assess clinical scores of anxiety, anger, and impulsiveness. Evoked potentials were recorded following the application of acoustic stimuli with increasing intensities; the LD was analysed using dipole source analysis. The mean LD was significantly higher in patients with BPD compared to controls. In the entire sample there were significant positive correlations of LD with state anxiety scores and STAXI subscores. The data contribute to the knowledge of neurophysiological alterations in patients with BPD, supporting the hypothesis of serotonergic dysregulation in the pathophysiology of the disorder. The significant clinical correlations suggest monoaminergic modulations of psychopathology on the symptom level.

[I-123] ADAM and SPECT in patients with borderline personality disorder and healthy control subjects.

OBJECTIVE: Serotonergic dysfunction is considered to be involved in the pathophysiology of borderline personality disorder (BPD). The aim of this study was to investigate serotonin transporter availability in patients with BPD as a marker of the central serotonergic system. METHODS: Eight unmedicated patients with BPD and 9 healthy control subjects received single photon emission computed tomography (SPECT) 4 hours after injection of 185 MBq [I-123] ADAM (2-([2-([dimethylamino]methyl)phenyl]thio)). As a measure of brain serotonin transporter (SERT) availability, ratios of specific-to-nonspecific [I-123] ADAM binding for the brainstem and hypothalamus were calculated with an occipital reference. Levels of impulsiveness and depressive symptoms were assessed with the Barratt Impulsiveness Scale and the Beck Depression Inventory. RESULTS: Mean specific-to-nonspecific ratios showed a 43% higher brainstem and a 12% higher hypothalamus ADAM binding in patients, compared with control subjects. We found significant correlations of ADAM binding with both age and impulsiveness but not depression. Associations of BIS scores with ADAM binding remained significant after controlling for age and depression (r = 0.69, p < 0.01). CONCLUSION: The study provides evidence of a serotonergic dysfunction in patients with BPD and suggests a serotonergic component in the pathophysiology of the disorder. SERT binding reflected the level of impulsiveness as a common feature in BPD.