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

Narcissism and central serotonergic neurotransmission in depression

OBJECTIVES

Based on previous research, it has been proposed that the development of depressive disorders is related to altered functioning of the serotonergic systems as well as the personality style, including narcissism. However, it is unclear to date how personality style, especially narcissism, depressive disorders and serotonergic activity are related.

METHODS

We included 74 patients with a depressive disorder (DP) and 74 healthy controls (HC) in the study. All participants completed the Personality Style and Disorder Inventory (PSDI) and the Beck Depression Inventory (BDI II). Moreover, we conducted EEG recordings for analysis of serotonergic neurotransmission by using the so-called intensity or loudness dependence of the auditory evoked potentials (LDAEP).

RESULTS

Significantly higher LDAEP results emerged for the DP group compared to the HC group, which indicated lower serotonergic activity in the patient's group. In addition, the positive correlation between ambitious-narcissistic personality and LDAEP reached significance in depressive patients.

LIMITATIONS

There was only a monocentric cross-sectional study with only one scale having differences between the two groups due to age and education.

CONCLUSIONS

Our data supports the theory of lower serotonergic activity in patients with depressive disorders and further suggests that high narcissistic personality traits are related to lower serotonergic neurotransmission in patients.

Sex differences in borderline personality disorder: A scoping review

Borderline Personality Disorder (BPD) is often perceived to be a female-predominant disorder in both research and clinical contexts. Although there is growing recognition of possible sex differences, the current literature remains fragmented and inconclusive. This scoping review aimed to synthesize available research evidence on potential sex differences in BPD. PsycINFO, PubMed, Scopus and Web-of-Science were searched from January 1982 to July 2022 surrounding the key concepts of sex and BPD. Data searching and screening processes followed the Joanna Briggs Institute methodology involving two independent reviewers, and a third reviewer if necessary, and identified 118 papers. Data regarding BPD symptoms, comorbid disorders, developmental factors, biological markers, and treatment were extracted. Data was summarized using the vote counting method or narrative synthesis depending on the availability of literature. Males with BPD were more likely to present externalizing symptoms (e.g., aggressiveness) and comorbid disorders (e.g., substance use), while females with BPD were more likely to present internalizing symptoms (e.g., affective instability) and comorbid disorders (e.g., mood and eating disorders). This review also revealed that substantially more research attention has been given to overall sex differences in baseline BPD symptoms and comorbid disorders. In contrast, there is a dearth of sex-related research pertaining to treatment outcomes, developmental factors, and possible biological markers of BPD. The present scoping review synthesized current studies on sex differences in BPD, with males more likely to present with externalizing symptoms in contrast to females. However, how this might change the prognosis of the disorder or lead to modifications of treatment has not been investigated. Most studies were conducted on western populations, mainly North American (55%) or European (33%), and there is a need for future research to also take into consideration genetic, cultural, and environmental concomitants. As the biological construct of 'sex' was employed in the present review, future research could also investigate the social construct 'gender'. Longitudinal research designs are needed to understand any longer-term sex influence on the course of the disorder.

Investigation of the Serotonergic Activity and the Serotonin Content in Serum and Platelet, and the Possible Role of the Serotonin Transporter in Patients with Depression

According to the monoamine hypothesis, the development of depression is associated with dysfunctions of the serotonergic system. Alterations in the serotonin transporter gene (5-HTTLPR), the serotonergic activity in the brain, and the content of serotonin (5-HT) have been related to depression and were examined separately by previous studies. This study investigates these parameters in 89 depressed patients and 89 healthy participants. We investigated the serotonergic activity measured by the loudness dependence of auditory evoked potentials (LDAEP). In addition to the examination of the serotonin content (serum and platelet), enzyme-linked immunosorbent assays (ELISA) were used and 5-HTTLPR genotypes were analyzed. We observed a lower serotonin content in patients compared to healthy participants. Further, we noticed a correlation between anxiety and depression-associated symptoms with serotonergic activity. Patients treated with SSRI/SNRI showed decreased contents of serum serotonin compared to patients without any psychotropic medication or other psychotropic medications. Since the serotonergic activity, peripheral serotonin content, and 5-HTTLPR were unrelated, the results suggest independent alterations of central and peripheral serotonergic systems in depression. In line with this finding, serotonergic activity was related to anxiety and depression symptoms. Furthermore, the applied medication seems to influence serum serotonin content in patients with depression.

Auditory event-related electroencephalographic potentials in borderline personality disorder

BACKGROUND

Borderline Personality Disorder (BPD) is characterized by mood dysregulation, impulsivity, identity disturbances, and a higher risk for suicide. Currently, the diagnosis is solely based on clinical observation of overt symptoms, and this can delay the detection of the disease and the timely start of appropriate treatment. Several candidate clinical tools have been studied to better characterize BPD, including event-related potentials (ERP). This review aimed at summarizing the results of the available ERP studies on BPD to clarify the possible application of this technique in the early diagnosis of BPD.

METHODS

A bibliographic search on PubMed and PsycInfo was performed in order to identify studies comprising individuals with BPD diagnosis and a control group that evaluated the ERP elicited by auditory stimuli.

RESULTS

Ten studies that explored various ERP components associated with auditory stimuli in BPD were included. Overall, the results showed that positive ERP (P50, P100, and P300) amplitude and latencies as well as loudness dependance were altered in BPD patients compared to controls, possibly reflecting deficits involving attention, mainly at its early stage, and executive functions.

LIMITATIONS

The reviewed studies used different ERP approaches and non-homogeneous BPD diagnostic criteria.

CONCLUSIONS

Auditory ERP appear to be a promising tool for the assessment of BPD patients, especially for early diagnosis and evaluation of cognitive symptoms.

Reduced white matter integrity in borderline personality disorder: A diffusion tensor imaging study

BACKGROUND

Borderline personality disorder (BPD) has a pervasive pattern of instability in interpersonal relationships, self-image, and emotions. BPD may be linked to an abnormal brain anatomy, but little is known about possible impairments of the white matter microstructure in BPD or their relationship with impulsivity or risky behaviors. The aims of the present study were to explore the relationship between BPD and diffusion tensor imaging (DTI) parameters and psychological tests.

METHODS

We evaluated 35 un-medicated BPD patients in a medication-free state and 50 healthy controls (HCs). We performed DTI tractography in BPD patients and HCs. The Childhood Trauma Questionnaire (CTQ), Profile of Mood State (POMS), State-Trait Anxiety Inventory (STAI), Beck Depression Inventory (BDI), Social Adaptation Self-Evaluation Scale (SASS), and Depression and Anxiety Cognition Scale (DACS) were administered to BPD patients and HCs.

RESULTS

A tract-based spatial statistics (TBSS) revealed that the BPD group had three clusters with a significantly lower axial diffusivity (AD) than the HC group: one located mainly in the cingulum and the other mainly in the inferior front-occipital fasciculus and inferior longitudinal fasciculus. Regarding the AD values, one cluster correlated negatively and significantly with POMS (Depression) and it was located in the cingulum, while another cluster correlated positively and significantly with DACS (Future Denial) and it was located in the inferior front-occipital fasciculus (IFOF).

LIMITATIONS

The small sample size of this study prevents us from forming any definitive conclusions, meaning that more studies are needed to confirm our findings. We are unable to generalize our findings to include other ethnic groups.

CONCLUSIONS

Our results suggested that hypo-metabolism in a front-limbic network dysfunction is characterized by the cingulum and a front-occipital network dysfunction characterized by the occipital lobe, while an occipital-temporal network dysfunction characterized by the inferior longitudinal fasciculus.

Association Between Borderline Personality Features and Temporal Summation of Second Pain: A Cross-Sectional Study

Individuals with greater borderline personality features may be vulnerable to chronic pain. Because pain is an unpleasant sensory and emotional experience, affect dysregulation as the core personality feature may be linked to pain hypersensitivity. Studies have found that greater borderline features are associated with increased intensity in clinical and experimental pain, and that depression mediates this increase. The current study further examined the association between borderline features and heat pain sensitivity, the contribution of affect dysregulation and the other borderline personality factors (identity problems, negative relationships, self-harming/impulsivity) to the association, and depression as a mediator. Additionally, we examined whether blunted sympathetic responses mediate the association between borderline features and temporal summation of second pain (TSSP). Thermal pain threshold, thermal TSSP and aftersensations pain were assessed in 79 healthy individuals with varying degrees of borderline features. TSSP is a proxy measure for central sensitization and refers to the gradual increase in pain to repeated nociceptive stimuli. A regression analysis showed that greater borderline features predicted greater TSSP (β = .22, p = .050, R² = .05). Borderline features were unrelated to pain threshold and TSSP decay. A stepwise regression showed greater TSSP in individuals with greater borderline features was accounted for by the negative relationships factor rather than the affect dysregulation factor. The results of mediational analyses showed depression and blunted sympathetic skin conductance responses mediated the positive association between TSSP and borderline features.

Modulation of auditory brainstem responses by serotonin and specific serotonin receptors

The neuromodulator serotonin is found throughout the auditory system from the cochlea to the cortex. Although effects of serotonin have been reported at the level of single neurons in many brainstem nuclei, how these effects correspond to more integrated measures of auditory processing has not been well-explored. In the present study, we aimed to characterize the effects of serotonin on far-field auditory brainstem responses (ABR) across a wide range of stimulus frequencies and intensities. Using a mouse model, we investigated the consequences of systemic serotonin depletion, as well as the selective stimulation and suppression of the 5-HT1 and 5-HT2 receptors, on ABR latency and amplitude. Stimuli included tone pips spanning four octaves presented over a forty dB range. Depletion of serotonin reduced the ABR latencies in Wave II and later waves, suggesting that serotonergic effects occur as early as the cochlear nucleus. Further, agonists and antagonists of specific serotonergic receptors had different profiles of effects on ABR latencies and amplitudes across waves and frequencies, suggestive of distinct effects of these agents on auditory processing. Finally, most serotonergic effects were more pronounced at lower ABR frequencies, suggesting larger or more directional modulation of low-frequency processing. This is the first study to describe the effects of serotonin on ABR responses across a wide range of stimulus frequencies and amplitudes, and it presents an important step in understanding how serotonergic modulation of auditory brainstem processing may contribute to modulation of auditory perception.

Gender determines cortisol and alpha-amylase responses to acute physical and psychosocial stress in patients with borderline personality disorder

Borderline personality disorder (BPD) is characterized by affective instability, unstable relationships, and identity disturbance. We measured salivary alpha-amylase (sAA) and salivary cortisol levels in all participants during exposure to the Trier Social Stress Test (TSST) and an electric stimulation stress. Seventy-two BPD patients were compared with 377 age- and gender- matched controls. The State and Trait versions of the Spielberger Anxiety Inventory test (STAI-S and STAI-T, respectively), the Profile of Mood State (POMS) tests, and the Beck Depression Inventory (BDI), the Depression and Anxiety Cognition Scale (DACS) were administered to participants before electrical stimulation. Following TSST exposure, salivary cortisol levels significantly decreased in female patients and significantly increased in male patients compared with controls. POMS tension-anxiety, depression-dejection, anger-hostility, fatigue, and confusion scores were significantly increased in BPD patients compared with controls. In contrast, vigor scores were significantly decreased in BPD patients relative to controls. Furthermore, STAI-T and STAI-S anxiety scores and BDI scores were significantly increased in BPD patient compared with controls. DACS scores were significantly increased in BPD patient compared with controls. Different stressors (e.g., psychological or physical) induced different responses in the HPA and SAM systems in female or male BPD patients.