What impact can brain stimulation interventions have on borderline personality disorder?

INTRODUCTION

Borderline personality disorder (BPD) is a severe mental disorder characterized by emotion dysregulation, impulsivity, neuropsychological impairment, and interpersonal instability, presenting with multiple psychiatric comorbidities, functional disability and reduced life expectancy due suicidal behaviors.

AREAS COVERED

In this perspective, the authors explore the application of noninvasive brain stimulation (NIBS) (rTMS, tDCS, and MST) in BPD individuals by considering a symptom-based approach, focusing on general BPD psychopathology, impulsivity and neuropsychological impairments, suicidality and depressive/anxious symptoms, and emotion dysregulation.

EXPERT OPINION

According to a symptoms-based approach, NIBS interventions (particularly rTMS and tDCS) are promising treatment options for BPD individuals improving core symptoms such as emotional and behavioral dysregulation, neuropsychological impairments and depressive symptoms. However, the heterogeneity of stimulation protocols and of assessment tools used to detect these changes limits the possibility to provide definitive recommendations according to a symptom-based approach. To implement such armamentarium in clinical practice, future NIIBS studies should further consider a lifespan perspective due to clinical variability over time, the role of psychiatric comorbidities affecting BPD individuals and the need to combine NIBS with specialized psychotherapeutic approaches for BPD patients and with functional neuroimaging studies.

Improving depressive symptoms in patients with schizophrenia using bilateral bipolar-nonbalanced prefrontal tDCS: Results from a double-blind sham-controlled trial

BACKGROUND

Treating depressive symptoms in patients with schizophrenia is challenging. While transcranical Dicrect Current Stimulation (tDCS) improved other core symptoms of schizophrenia, conflicting results have been obtained on depressive symptoms. Thus, we aimed to expand current evidence on tDCS efficacy to improve depressive symptoms in patients with schizophrenia.

METHODS

A double-blind RCT was performed with patients randomized to 2 mA active-tDCS or sham-tDCS (15 daily sessions) with a bilateral bipolar-nonbalanced prefrontal placement (anode: left Dorsolateral prefrontal cortex; cathode: right orbitofrontal region). Clinical outcomes included variations of Calgary Depression Scale for Schizophrenia total score (CDSS) and of Depression-hopelessness and Guilty idea of reference-pathological guilt factors. Analysis of covariance was performed evaluating between-group changes over time. The presence/absence of probable clinically significant depression was determined when CDSS > 6.

RESULTS

As 50 outpatients were included (both groups, n = 25), significant improvements following active-tDCS were observed for CDSS total score (p = 0.001), Depression-hopelessness (p = 0.001) and Guilty idea of reference-pathological guilt (p = 0.03). Considering patients with CDSS>6 (n = 23), compared to sham, active-tDCS significantly improved CDSS total score (p < 0.001), Depression-hopelessness (p = 0.001) but Guilty idea of reference-pathological guilt only marginally improved (p = 0.051). Considering response rates of clinically significant depression, important reductions of CDSS score were observed (78 % of the sample scored ≤6; active-tDCS, n = 23; sham-tDCS, n = 16; p = 0.017). Early wakening item did not significantly change in any group.

LIMITATIONS

The study lacks a follow-up period and evaluation of tDCS effects on psychosocial functioning.

CONCLUSIONS

Bilateral bipolar-nonbalanced prefrontal tDCS is a successful protocol for the treatment of depressive symptoms in patients with schizophrenia.

Effects of bilateral, bipolar-nonbalanced, frontal transcranial Direct Current Stimulation (tDCS) on negative symptoms and neurocognition in a sample of patients living with schizophrenia: Results of a randomized double-blind sham-controlled trial

Negative symptoms (NS), conceived as Avolition-Apathy (AA) and Expressive Deficit (EXP) domains, and neurocognitive impairments represent unmet therapeutic needs for patients with schizophrenia. The present study investigated if bilateral bipolar-nonbalanced frontal transcranial Direct Current Stimulation (tDCS) could improve these psychopathological dimensions. This randomized, double-blind, sham-controlled study (active-tDCS versus sham-tDCS, both, n = 25) included 50 outpatients diagnosed with schizophrenia clinically stabilized. Patients received 20-min 2 mA active-tDCS or sham-tDCS (anode: left Dorsolateral Prefrontal Cortex; cathode: right orbitofrontal region). Primary outcomes included: PANSS-Negative subscale, Negative Factor (Neg-PANSS), AA and EXP domains; neurocognitive performance at Brief Assessment of Cognition in Schizophrenia. Secondary outcomes included: PANSS subscales and total score, Disorganized/Concrete (DiscC-PANSS) and Positive Factors, Clinical Global Impression (CGI) scores, clinical insight at Scale to Assess Unawareness of Mental Disorder (SUMD). Analysis of covariance (ANCOVA) was performed evaluating between-group changes over time. Significant improvements following active-tDCS were observed for all NS measures (all, p < 0.001; d > 0.8) and for working memory (p = 0.025, d = 0.31). Greater variations following to active treatment emerged also for PANSS-General Psychopathology subscale (p < 0.001; d = 0.54), PANSS total score (p < 0.001; d = 0.69), CGI indexes (all, p < 0.001; d > 0.6), DiscC-PANSS (p < 0.001; d = 0.80) and SUMD-general Unawareness index (p = 0.005; d = 0.15) but not for positive symptoms and others insight measures. Good safety/tolerability profiles were found. Bilateral bipolar-nonbalanced frontal-tDCS is a non-pharmacological approach in schizophrenia effectively improving NS, particularly the AA and EXP domains, probably acting by modulating dysfunctional cortical-subcortical networks. Preliminary results also suggest working memory improvements following tDCS. Further studies are needed to confirm the neurobiological basis of these results.

Current Evidence and Theories in Understanding the Relationship between Cognition and Depression in Childhood and Adolescence: A Narrative Review

The present narrative review has covered the current evidence regarding the role of cognitive impairments during the early phase of major depressive disorder (MDD), attempting to describe the cognitive features in childhood, adolescence and in at-risk individuals. These issues were analyzed considering the trait, scar and state hypotheses of MDD by examining the cold and hot dimensions, the latter explained in relation to the current psychological theoretical models of MDD. This search was performed on several electronic databases up to August 2022. Although the present review is the first to have analyzed both cold and hot cognitive impairments considering the trait, scar and state hypotheses, we found that current evidence did not allow to exclusively confirm the validity of one specific hypothesis since several equivocal and discordant results have been proposed in childhood and adolescence samples. Further studies are needed to better characterize possible cognitive dysfunctions assessing more systematically the impairments of cold, hot and social cognition domains and their possible interaction in a developmental perspective. An increased knowledge on these topics will improve the definition of clinical endophenotypes of enhanced risk to progression to MDD and, to hypothesize preventive and therapeutic strategies to reduce negative influences on psychosocial functioning and well-being.