The consequences of the new European reclassification of non-invasive brain stimulation devices and the medical device regulations pose an existential threat to research and treatment: An invited opinion paper

A significant amount of European basic and clinical neuroscience research includes the use of transcranial magnetic stimulation (TMS) and low intensity transcranial electrical stimulation (tES), mainly transcranial direct current stimulation (tDCS). Two recent changes in the EU regulations, the introduction of the Medical Device Regulation (MDR) (2017/745) and the Annex XVI have caused significant problems and confusions in the brain stimulation field. The negative consequences of the MDR for non-invasive brain stimulation (NIBS) have been largely overlooked and until today, have not been consequently addressed by National Competent Authorities, local ethical committees, politicians and by the scientific communities. In addition, a rushed bureaucratic decision led to seemingly wrong classification of NIBS products without an intended medical purpose into the same risk group III as invasive stimulators. Overregulation is detrimental for any research and for future developments, therefore researchers, clinicians, industry, patient representatives and an ethicist were invited to contribute to this document with the aim of starting a constructive dialogue and enacting positive changes in the regulatory environment.

Unraveling the brain mechanisms of source monitoring with non-invasive brain stimulation: A systematic review

Background/Objective

Source monitoring refers to the ability to determine the source of memories and encompasses three subprocesses: internal source monitoring, reality monitoring, and external source monitoring. Neuroimaging studies provide valuable insights about neural correlates of source monitoring, but the causal relationship between brain and behavior is lacking. This study aimed to identify brain circuits involved in source monitoring by synthesizing the effects of brain stimulation on source monitoring as a function of the targeted brain regions or circuits.

Method

We conducted a systematic review of interventional studies that have examined the effects of brain stimulation on source monitoring across six databases. The principal outcome was the difference of source monitoring performance between active and control stimulation conditions.

Results

23 studies (920 healthy participants and 54 patients with schizophrenia) were included. Our findings revealed the involvement of i) the lateral prefrontal and temporoparietal cortices in internal source monitoring, ii) the medial prefrontal and temporoparietal cortices in reality monitoring, and iii) the precuneus and the left angular gyrus in external source monitoring.

Conclusions

These findings deepen our understanding of the brain mechanisms of source monitoring and highlight specific stimulation targets to alleviate source monitoring deficits.

Case report: accelerated cathodal HD-tDCS over the right dorsolateral prefrontal cortex in hoarding disorder

Hoarding disorder is an under-recognized condition characterized by the excessive acquisition of possessions and difficulty in disposing of them, which can have dramatic consequences. As hoarding disorder is difficult to treat and associated with high levels of disability in all areas of functioning, there appears to be a critical need to develop novel, tailored therapeutic strategies. Non-invasive brain stimulation techniques hold promise as potential therapeutic interventions for various psychiatric conditions and as a tool to modulate impulsivity when applied over the dorsolateral prefrontal cortex (DLPFC). Therefore, we hypothesized that delivering accelerated cathodal high-definition direct transcranial stimulation (HD-tDCS) over the right DLPFC could be a suitable approach to alleviate symptoms in patients with hoarding disorder. In a case report, we observed beneficial clinical effects on acquisition and depressive symptoms after 15 sessions of three daily 20-min sessions. Accelerated cathodal HD-tDCS over the right DLPFC appears to be a safe and appropriate intervention for patients with hoarding disorder. However, randomized, sham-controlled trials are needed to further validate these encouraging findings.

A non-randomized pilot trial of the use of prazosin in the prevention of transition from acute stress disorder to post-traumatic stress disorder

BACKGROUND

Following a traumatic event, 40-80% of the patients with acute stress disorder (ASD) will develop post-traumatic stress disorder (PTSD), 67% at 6 months. Alpha1-blockers are effective in treating some symptoms of PTSD but their usefulness in acute stress situations remains unclear. We hypothesized that reducing noradrenergic hyperactivity with an alpha1-blocker during the acute phase after a traumatic event could prevent the transition to PTSD in patients with ASD.

OBJECTIVE

To investigate the efficacy and safety of a 1-month course of alpha1-blocker (prazosin) to prevent the transition to PTSD in patients with ASD at 6 months.

METHOD

In a monocentric open-label prospective pilot study, 15 patients with ASD were included within 3-7 days of exposure to a traumatic event. After enrolment, they received prazosin LP at home at bedtime at 2.5 mg/day for 7 days and then 5 mg/day for 21 days. Incidence of PTSD was assessed at 6 months using the Clinician Administrated PTSD Scale (CAPS).

RESULTS

At 6 months, 22% of patients who completed the study (2/9) met the diagnostic criteria for PTSD. This rate was significantly lower than that observed in previous studies (67%; p = .047). The treatment was well tolerated and there were no serious adverse events.

CONCLUSIONS

These preliminary findings indicating the safety of prazosin and suggesting its potential to prevent the development of PTSD in ASD require to be replicated in large-scale randomized placebo-controlled studies.Trial registration: The study was pre-registered on a public database (www.clinicalTrials.gov identifier: NCT03045016).

Basic auditory processing and its relationship with symptoms in patients with schizophrenia: A systematic review

Processing of basic auditory features, one of the earliest stages of auditory perception, has been the focus of considerable investigations in schizophrenia. Although numerous studies have shown abnormalities in pitch perception in schizophrenia, other basic auditory features such as intensity, duration, and sound localization have been less explored. Additionally, the relationship between basic auditory features and symptom severity shows inconsistent results, preventing concrete conclusions. Our aim was to present a comprehensive overview of basic auditory processing in schizophrenia and its relationship with symptoms. We conducted a systematic review according to the PRISMA guidelines. PubMed, Embase, and PsycINFO databases were searched for studies exploring auditory perception in schizophrenia compared to controls, with at least one behavioral task investigating basic auditory processing using pure tones. Forty-one studies were included. The majority investigated pitch processing while the others investigated intensity, duration and sound localization. The results revealed that patients have a significant deficit in the processing of all basic auditory features. Although the search for a relationship with symptoms was limited, auditory hallucinations experience appears to have an impact on basic auditory processing. Further research may examine correlations with clinical symptoms to explore the performance of patient subgroups and possibly implement remediation strategies.

Digitalized transcranial electrical stimulation: A consensus statement

OBJECTIVE

Although relatively costly and non-scalable, non-invasive neuromodulation interventions are treatment alternatives for neuropsychiatric disorders. The recent developments of highly-deployable transcranial electric stimulation (tES) systems, combined with mobile-Health technologies, could be incorporated in digital trials to overcome methodological barriers and increase equity of access. The study aims are to discuss the implementation of tES digital trials by performing a systematic scoping review and strategic process mapping, evaluate methodological aspects of tES digital trial designs, and provide Delphi-based recommendations for implementing digital trials using tES.

METHODS

We convened 61 highly-productive specialists and contacted 8 tES companies to assess 71 issues related to tES digitalization readiness, and processes, barriers, advantages, and opportunities for implementing tES digital trials. Delphi-based recommendations (>60% agreement) were provided.

RESULTS

The main strengths/opportunities of tES were: (i) non-pharmacological nature (92% of agreement), safety of these techniques (80%), affordability (88%), and potential scalability (78%). As for weaknesses/threats, we listed insufficient supervision (76%) and unclear regulatory status (69%). Many issues related to methodological biases did not reach consensus. Device appraisal showed moderate digitalization readiness, with high safety and potential for trial implementation, but low connectivity.

CONCLUSIONS

Panelists recognized the potential of tES for scalability, generalizability, and leverage of digital trials processes; with no consensus about aspects regarding methodological biases.

SIGNIFICANCE

We further propose and discuss a conceptual framework for exploiting shared aspects between mobile-Health tES technologies with digital trials methodology to drive future efforts for digitizing tES trials.

Examining transcranial random noise stimulation as an add-on treatment for persistent symptoms in schizophrenia (STIM'Zo): a study protocol for a multicentre, double-blind, randomized sham-controlled clinical trial

Background

One out of three patients with schizophrenia failed to respond adequately to antipsychotics and continue to experience debilitating symptoms such as auditory hallucinations and negative symptoms. The development of additional therapeutic approaches for these persistent symptoms constitutes a major goal for patients. Here, we develop a randomized-controlled trial testing the efficacy of high-frequency transcranial random noise stimulation (hf-tRNS) for the treatment of resistant/persistent symptoms of schizophrenia in patients with various profiles of symptoms, cognitive deficits and illness duration. We also aim to investigate the biological and cognitive effects of hf-tRNS and to identify the predictors of clinical response.

Methods

In a randomized, double-blind, 2-arm parallel-group, controlled, multicentre study, 144 patients with schizophrenia and persistent symptoms despite the prescription of at least one antipsychotic treatment will be randomly allocated to receive either active (n = 72) or sham (n = 72) hf-tRNS. hf-tRNS (100–500 Hz) will be delivered for 20 min with a current intensity of 2 mA and a 1-mA offset twice a day on 5 consecutive weekdays. The anode will be placed over the left dorsolateral prefrontal cortex and the cathode over the left temporoparietal junction. Patients’ symptoms will be assessed prior to hf-tRNS (baseline), after the 10 sessions, and at 1-, 3- and 6-month follow-up. The primary outcome will be the number of responders defined as a reduction of at least 25% from the baseline scores on the Positive and Negative Syndrome Scale (PANSS) after the 10 sessions. Secondary outcomes will include brain activity and connectivity, source monitoring performances, social cognition, other clinical (including auditory hallucinations) and biological variables, and attitude toward treatment.

Discussion

The results of this trial will constitute a first step toward establishing the usefulness of hf-tRNS in schizophrenia whatever the stage of the illness and the level of treatment resistance. We hypothesize a long-lasting effect of active hf-tRNS on the severity of schizophrenia symptoms as compared to sham. This trial will also have implications for the use of hf-tRNS as a preventive intervention of relapse in patients with schizophrenia.

Trial registration

ClinicalTrials.gov NCT02744989. Prospectively registered on 20 April 2016

Cognitive insight in individuals with an at-risk mental state for psychosis: A meta-analysis

AIM

To compare cognitive insight abilities measured with the Beck Cognitive Insight Scale (BCIS) between individuals with an at-risk mental state (ARMS) and healthy controls.

METHOD

Review and meta-analysis based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A search for articles investigating cognitive insight in ARMS in the MEDLINE and ScienceDirect databases revealed five studies including 303 ARMS and 376 controls. Regarding BCIS subscales, ARMS individuals displayed significant higher scores for self-certainty than controls with a small-to-moderate effect size (ESg = 0.45 [0.23;0.67], P < .005), whereas no significant difference was observed for self-reflectiveness (ESg = -0.56 [-0.18;1.29], P = .14). No significant differences were observed between ARMS and controls for overall cognitive insight abilities as indexed by the BCIS composite score (ESg = -0.24 [-0.43;0.91], P = .45).

CONCLUSIONS

Self-certainty abnormalities seem to predate the expression of full-blown psychotic episode and to be higher in ARMS than in healthy controls. By contrast, ARMS did not display abnormal self-reflectiveness and overall cognitive insight abilities.

Evidence-Based Guidelines and Secondary Meta-Analysis for the Use of Transcranial Direct Current Stimulation in Neurological and Psychiatric Disorders

BACKGROUND

Transcranial direct current stimulation has shown promising clinical results, leading to increased demand for an evidence-based review on its clinical effects.

OBJECTIVE

We convened a team of transcranial direct current stimulation experts to conduct a systematic review of clinical trials with more than 1 session of stimulation testing: pain, Parkinson's disease motor function and cognition, stroke motor function and language, epilepsy, major depressive disorder, obsessive compulsive disorder, Tourette syndrome, schizophrenia, and drug addiction.

METHODS

Experts were asked to conduct this systematic review according to the search methodology from PRISMA guidelines. Recommendations on efficacy were categorized into Levels A (definitely effective), B (probably effective), C (possibly effective), or no recommendation. We assessed risk of bias for all included studies to confirm whether results were driven by potentially biased studies.

RESULTS

Although most of the clinical trials have been designed as proof-of-concept trials, some of the indications analyzed in this review can be considered as definitely effective (Level A), such as depression, and probably effective (Level B), such as neuropathic pain, fibromyalgia, migraine, post-operative patient-controlled analgesia and pain, Parkinson's disease (motor and cognition), stroke (motor), epilepsy, schizophrenia, and alcohol addiction. Assessment of bias showed that most of the studies had low risk of biases, and sensitivity analysis for bias did not change these results. Effect sizes vary from 0.01 to 0.70 and were significant in about 8 conditions, with the largest effect size being in postoperative acute pain and smaller in stroke motor recovery (nonsignificant when combined with robotic therapy).

CONCLUSION

All recommendations listed here are based on current published PubMed-indexed data. Despite high levels of evidence in some conditions, it must be underscored that effect sizes and duration of effects are often limited; thus, real clinical impact needs to be further determined with different study designs.

Advancing clinical response characterization to frontotemporal transcranial direct current stimulation with electric field distribution in patients with schizophrenia and auditory hallucinations: a pilot study

Transcranial direct current stimulation (tDCS) has been proposed as a therapeutic option for treatment-resistant auditory verbal hallucinations (AVH) in schizophrenia. In such cases, repeated sessions of tDCS are delivered with the anode over the left prefrontal cortex and the cathode over the left temporoparietal junction. Despite promising findings, the clinical response to tDCS is highly heterogeneous among patients. Here, we explored baseline differences between responders and nonresponders to frontotemporal tDCS using electric field modeling. We hypothesized that responders would display different tDCS-induced electric field strength in the brain areas involved in AVH compared to nonresponders.Using baseline structural MRI scans of 17 patients with schizophrenia and daily AVH who received 10 sessions of active frontotemporal tDCS, we constructed individual realistic whole brain models estimating electric field strength. Electric field maps were compared between responders (n = 6) and nonresponders to tDCS (n = 11) using an independent two-sample t test. Clinical response was defined as at least a 50% decrease of AVH 1 month after the last tDCS session.Results from the electric field map comparison showed that responders to tDCS displayed higher electric field strength in the left transverse temporal gyrus at baseline compared to nonresponders (T = 2.37; p = 0.016; 32 voxels).These preliminary findings suggested that the strength of the tDCS-induced electric field reaching the left transverse temporal gyrus could play an important role in the response to frontotemporal tDCS. In addition, this work suggests the interest of using electric field modeling to individualize tDCS and increase response rate.

[Transcranial electrical brain stimulation methods for treatment of negative symptoms in schizophrenia]

Über die letzten Jahre entwickelten sich Neuromodulationsverfahren zu einer dritten Säule neben Pharmakotherapie und Psychotherapie in der Behandlung psychischer Erkrankungen. Besonders in der Behandlung von Menschen mit einer Schizophrenie könnten Hirnstimulationsverfahren eine Alternative oder Ergänzung zu den etablierten Therapiestrategien darstellen. Die meist vorhandenen Positivsymptome können zumeist mit Antipsychotika adäquat behandelt werden. Gerade bei Patienten mit Schizophrenie besitzen jedoch Negativsymptome einen überdauernden Krankheitswert und beeinflussen den Verlauf durch globale Antriebsverarmung und beeinträchtigte Kognition im alltäglichen Leben negativ. Dieser Übersichtsartikel stellt eine Zusammenfassung über die verschiedenen nichtinvasiven Hirnstimulationsverfahren transkranielle Gleichstromstimulation (transcranial direct current stimulation, tDCS), Wechselstromstimulation (transcranial alternating current stimulation, tACS) sowie Rauschstromstimulation (transcranial random noise stimulation, tRNS) zur Behandlung der Negativsymptomatik bei Schizophrenie dar. Die neuen transkraniellen Hirnstimulationsverfahren könnten dabei helfen, gestörte neuronale Vernetzungen wieder herzustellen und die Konnektivität vor allem der dorsolateralen präfrontalen Anteile des Kortex zu verbessern. Einige Studien weisen auf eine Verbesserung der Negativsymptome durch Behandlung mit tDCS, tACS bzw. tRNS hin und könnten so neue Therapiemöglichkeiten in der Behandlung der Schizophrenie darstellen.

Repetitive transcranial magnetic stimulation (rTMS) for schizophrenia patients treated with clozapine

OBJECTIVES

Biological strategies to improve treatment efficacy in clozapine-treated patients are urgently needed. Repetitive transcranial magnetic stimulation (rTMS) merits consideration as intervention for patients with persistent auditory hallucinations (AH) or negative symptoms (NS) not responding sufficiently to clozapine treatment.

METHODS

Data from 10 international RCTs of rTMS for patients being treated with clozapine were pooled. Two levels of symptomatic response were defined: improvement of ≥20% and ≥50% on study-specific primary endpoint scales. Changes in the positive and negative syndrome scale (PANSS) from baseline to endpoint assessment were also analysed.

RESULTS

Analyses of 131 patients did not reveal a significant difference for ≥20% and ≥50% response thresholds for improvement of AH, negative or total symptoms between active and sham rTMS groups. The number needed to treat (NNT) for an improvement in persistent AH was nine following active rTMS. PANSS scores did not improve significantly from baseline to endpoint between active and sham groups in studies investigating NS and AH.

CONCLUSIONS

rTMS as a treatment for persistent symptoms in clozapine-treated patients did not show a beneficial effect of active compared to sham treatment. For AH, the size of the NNTs indicates a possible beneficial effect of rTMS.

Using EEG to Predict Clinical Response to Electroconvulsive Therapy in Patients With Major Depression: A Comprehensive Review

Introduction: An important approach to improve the therapeutic effect of electroconvulsive therapy (ECT) may be to early characterize patients who are more likely to respond. Our objective was to explore whether baseline electroencephalography (EEG) settings before the beginning of ECT treatment can predict future clinical response to ECT in patients with depressive disorder. Methods: We conducted a systematic search in the MEDLINE, EMBASE, PsycINFO, Web of Science, and Cochrane Central Register of Controlled Trials (CENTRAL) databases to identify studies using EEG in adults with depressive disorder treated by ECT. To investigate the predictive value of baseline EEG on clinical outcomes of ECT, we extracted from the retrieved studies and qualitatively described the association between the baseline EEG markers characteristics and the rates of future responders and/or remitters to ECT. Results: The primary search yielded 2,531 potentially relevant citations, and 12 articles were selected according to inclusion criteria. Most of the studies were prospective studies with small sample size. Sociodemographic and clinical characteristics of patients, ECT settings, EEG settings, and outcomes were heterogeneous. Event-related potential (ERP) paradigms were used in three studies, polysomnography was used in three studies, and the six other studies used EEG to measure cerebral connectivity and activity. Conclusions: P300 amplitude, coherence, and connectivity measures were correlated with remission in patients with depression treated by ECT. Sleep EEG recordings seemed not to be correlated with remission after ECT. Further prospective studies with large sample size are needed to determine optimal EEG parameters associated with clinical response to ECT in depressive disorder. Systematic Review Registration: PROSPERO CRD42020181978.

The Effects of Transcranial Electrical Stimulation of the Brain on Sleep: A Systematic Review

Transcranial Electrical Stimulation (tES) is a promising non-invasive brain modulation tool. Over the past years, there have been several attempts to modulate sleep with tES-based approaches in both the healthy and pathological brains. However, data about the impact on measurable aspects of sleep remain scattered between studies, which prevent us from drawing firm conclusions. We conducted a systematic review of studies that explored the impact of tES on neurophysiological sleep oscillations, sleep patterns measured objectively with polysomnography, and subjective psychometric assessments of sleep in both healthy and clinical samples. We searched four main electronic databases to identify studies until February 2020. Forty studies were selected including 511 healthy participants and 452 patients. tES can modify endogenous brain oscillations during sleep. Results concerning changes in sleep patterns are conflicting, whereas subjective assessments show clear improvements after tES. Possible stimulation-induced mechanisms within specific cortico-subcortical sleep structures and networks are discussed. Although these findings cannot be directly transferred to the clinical practice and sleep-enhancing devices development for healthy populations, they might help to pave the way for future researches in these areas. PROSPERO registration number 178910.

The Combination of Propofol and Ketamine Does Not Enhance Clinical Responses to Electroconvulsive Therapy in Major Depression-The Results From the KEOpS Study

Objective

We investigated the clinical effects of the combination of ketamine and propofol as anesthetic agents during electroconvulsive therapy (ECT) in patients with uni- or bipolar major depressive episodes. We hypothesized that ketamine may confer short- and long- term advantages in improving depressive symptoms at the early stages of ECT.

Methods

In a randomized placebo-controlled trial, remission rates after 4 and 8 weeks of ECT were compared between patients who were randomly allocated to receive either the combination of ketamine (0.5 mg/kg) + propofol (n= 11) or placebo + propofol (n = 16). Depressive symptoms were assessed weekly using the Montgomery-Åsberg Depression Rating Scale (MADRS); ECT sessions were administered twice per week for a maximum of 8 weeks (16 sessions).

Results

After 4 weeks, we observed significantly fewer remitters (MADRS score < 10) in the ketamine + propofol group (0/11; 0%) than in the placebo + propofol group (5/16; 31%; χ² = 4.22; p = 0.040). No significant difference was observed between the two groups regarding the number of patients who achieved remission weekly throughout the study period (Chi² = 3.588; p = 0.058). The mean duration of seizures was significantly shorter in the ketamine + propofol group than in the placebo + propofol group.

Conclusions

The results from the current study corroborated results from previously published studies and did not support the use of the combination of ketamine + propofol as an anesthetic agent for ECT in patients with major depressive episodes in clinical settings.

Abnormalities of the late positive potential during emotional processing in individuals with psychopathic traits: a meta-analysis

BACKGROUND

Individuals with psychopathic traits display deficits in emotional processing. A key event-related potential component involved in emotional processing is the late positive potential (LPP). In healthy controls, LPP amplitude is greater in response to negative stimuli than to positive or neutral stimuli. In the current study, we aimed to compare LPP amplitudes between individuals with psychopathic traits and control subjects when presented with negative, positive or neutral stimuli. We hypothesized that LPP amplitude evoked by emotional stimuli would be reduced in individuals with psychopathic traits compared to healthy controls.

METHODS

After a systematic review of the literature, we conducted a meta-analysis to compare LPP amplitude elicited by emotional stimuli in individuals with psychopathic traits and healthy controls.

RESULTS

Individuals with psychopathic traits showed significantly reduced LPP amplitude evoked by negative stimuli (mean effect size = -0.47; 95% CI -0.60 to -0.33; p < 0.005) compared to healthy controls. No significant differences between groups were observed for the processing of positive (mean effect size = -0.15; 95% CI -0.42 to 0.12; p = 0.28) and neutral stimuli (mean effect size = -0.12; 95% CI 0.31 to 0.07; p = 0.21).

CONCLUSIONS

Measured by LPP amplitude, individuals with psychopathic traits displayed abnormalities in the processing of emotional stimuli with negative valence whereas processing of stimuli with positive and neutral valence was unchanged as compared with healthy controls.

Gamma transcranial alternating current stimulation in patients with negative symptoms in schizophrenia: A case series

Non-invasive transcranial brain stimulation therapies, such as transcranial direct current stimulation, have been found to improve negative symptoms in schizophrenia. Another new technique is transcranial alternating current stimulation (tACS). Here we report a series of three patient treated with twice-daily 10min prefrontal 40Hz tACS stimulation over ten days. Patients showed an improvement in the Positive and Negative Syndrome Scale, Scale for the Assessment of Negative Symptoms, and subjective well-being. Furthermore, there was an improvement in the Trail Making Test and word fluency. ytACS merits further investigation in the treatment of schizophrenia symptoms.

Ethnic minority position and migrant status as risk factors for psychotic symptoms in the general population: a meta-analysis

Psychotic symptoms (PS) are experienced by a substantial proportion of the general population. When not reaching a threshold of clinical relevance, these symptoms are defined as psychotic experiences (PEs) and may exist on a continuum with psychotic disorders. Unfavorable socio-environmental conditions, such as ethnic minority position (EMP) and migrant status (MS), may increase the risk of developing PS and PEs. We conducted an electronic systematic review and a meta-analysis assessing the role of EMP and MS for the development and persistence of PS in the general population. Sub-group analyses were performed investigating the influence of ethnic groups, host countries, age, types of PS, and scales. Twenty-four studies met our inclusion criteria. EMP was a relevant risk factor for reporting PS [odds ratio (OR) 1.44, 95% confidence interval (CI) 1.22-1.70) and PEs (OR 1.36, 95% CI 1.16-1.60). The greatest risk was observed in people from the Maghreb and the Middle East ethnic groups in Europe (OR 3.30, 95% CI 2.09-5.21), in Hispanic in the USA (OR 1.98, 95% CI 1.43-2.73), and in the Black populations (OR 1.85, 95% CI 1.39-2.47). We found a significant association between MS and delusional symptoms (OR 1.47, 95% CI 1.33-1.62). We found no association between EMP and persistence of PEs.EMP was associated with increased risk of reporting PS and PEs, and the risk was higher in ethnic groups facing deprivation and discrimination. We found an association between MS and delusional symptoms. These results raise questions about the precise role of socio-environmental factors along the psychosis continuum.

Management of depression in patients with schizophrenia spectrum disorders: a critical review of international guidelines

OBJECTIVES

Depression is a frequent but potentially treatable clinical dimension in patients with schizophrenia spectrum disorders (PWS). However, there is a lack of consensual recommendations regarding the optimal strategy to manage depression in PWS. In this study, we aimed to compare the various proposed strategies to define a core set of valid care recommendations for depression management in PWS.

METHODS

After a systematic search of the literature, the methodological quality of 10 international guidelines from four continents was compared using a validated guideline appraisal instrument (AGREE II). Key recommendations for the management of depression in PWS were subsequently reviewed and discussed.

RESULTS

The methodological quality of the guidelines was heterogeneous. Although all guidelines proposed pharmacotherapy, psychosocial interventions were a minor concern. Waiting for antipsychotic effects mostly was recommended during the acute phase of schizophrenia. During the postpsychotic phase of the illness, a switch to a second-generation antipsychotic and/or the adjunction of an antidepressant were the primary recommendations. Cognitive behavioural therapy and other medications were considered with strong variations.

CONCLUSIONS

Further studies are needed to strengthen the level of evidence for antidepressive approaches in PWS. The inclusion of PWS as stakeholders is also considered to be a major issue for future guideline development.

Non-invasive brain stimulation for negative symptoms in schizophrenia: An updated systematic review and meta-analysis

BACKGROUND

Schizophrenia is a mental disorder with significant socioeconomic burden. Although current pharmacological treatments are effective for treating positive symptoms, medications have little-to-no effect in the treatment of negative symptoms.

OBJECTIVE

To assess the efficacy of non-invasive brain stimulation (NIBS) for negative symptoms in schizophrenia in randomized clinical trials (RCTs).

METHODS

A systematic review in Medline and Cochrane Library databases was performed up to May 31, 2017. The primary outcome was Hedges' g for continuous scores in a random-effects model. Heterogeneity was evaluated with the I² and χ² tests. Publication bias was assessed using Begg's funnel plot.

RESULTS

31 RCTs (n = 1272) were included, most with small-to-modest sample sizes. Both repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) were superior to sham (Hedges' g = 0.19; 95% CI 0.07-0.32; and 0.5; 0.02-0.97, respectively). Only one study evaluated the use of transcutaneous auricular vagus nerve stimulation (taVNS). The funnel plot and Eggers test showed that the risk of publication bias was low. In relation to heterogeneity, we found an I² of 0% (p = 0.749) and 51.3% (0.055) for rTMS and tDCS, respectively.

CONCLUSION

Both rTMS and tDCS were superior to sham stimulation for ameliorating negative symptoms in schizophrenia. We found no considerable heterogeneity or publication bias in our analysis, corroborating the strength of our findings. Not enough studies on other NIBS techniques, such as taVNS, were found for an isolated analysis. Further RCTs with larger sample sizes are needed to clarify the specific impact of NIBS on negative symptoms in schizophrenia.

Usefulness of the Montreal Cognitive Assessment (MoCA) to monitor cognitive impairments in depressed patients receiving electroconvulsive therapy

There is a lack of consensual tools for evaluating the cognitive side-effects in patients with depression who are treated with electroconvulsive therapy (ECT). The objective of this study was to evaluate the usefulness of the Montreal Cognitive Assessment (MoCA) and of the Mini Mental State Examination (MMSE) to monitor cognitive changes in patients with depression receiving ECT. Cognitive functioning was assessed prospectively in 48 patients with unipolar or bipolar depression before and after an ECT course. ECT-induced cognitive impairments were defined as a decrease of at least 2 points on the MoCA and the MMSE total scores and of at least one point on each sub-score. At baseline, the MoCA detected a higher number of patients with cognitive deficits than the MMSE. After ECT, the MoCA and MMSE total scores were comparable, but the MoCA detected more impairments than did the MMSE for visuo-executive, memory and language subscores. ECT significantly decreased the language capacities but improved the visuo-executive and abstraction performances measured by MoCA. In remitters, the MoCA total score and visuo-executive and abstraction performances were significantly improved, while other cognitive functions remained unchanged. The MoCA is a useful screening tool for monitoring cognitive functioning during an ECT course.

A single session of repetitive transcranial magnetic stimulation of the prefrontal cortex reduces cue-induced craving in patients with gambling disorder

BACKGROUND

Gambling disorder (GD) is common and disabling addictive disorder. In patients with substance use disorders, the application of repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) offers promise to alleviate craving. We hypothesized that applying real compared to sham rTMS over the left DLPFC would reduce gambling craving in patients with GD.

METHODS

In a randomized sham-controlled crossover design, 22 treatment-seeking patients with GD received real or sham treatment with high frequency rTMS over the left DLPFC followed a week later by the other type of treatment. Before and after each rTMS session, participants rated their gambling craving (from 0 to 100) before and after viewing a gambling video used as a cue. We used the Yale-Brown Obsessive Compulsive Scale adapted for Pathological Gambling to assess gambling behavior before and 7 days after each rTMS session.

RESULTS

As compared to sham (mean +0.74; standard deviation±3.03), real rTMS significantly decreased cue-induced craving (-2.12±3.39; F_(1,19)=4.87; P=0.04; partial η²=0.05; 95% CI: 0.00-0.21). No significant effect of rTMS was observed on gambling behavior.

CONCLUSIONS

Patients with GD reported decreased cue-induced craving following a single session of high frequency rTMS applied over the left DLPFC. Further large randomized controlled studies are needed to determine the usefulness of rTMS in GD.

Effects of smoking status and MADRS retardation factor on response to low frequency repetitive transcranial magnetic stimulation for depression

BACKGROUND

Despite growing evidence supporting the clinical interest of repetitive transcranial magnetic stimulation (rTMS) in treatment-resistant depression (TRD), little is known regarding the effects of clinical and sociodemographic factors on the clinical outcome in patients.

METHODS

We retrospectively investigated the effects of clinical (using the 3-factor model of the Montgomery-Åsberg depression rating scale [MADRS] encompassing dysphoria, retardation and vegetative symptoms) and sociodemographic characteristics of participants on clinical outcome in a sample of 54 TRD patients receiving low frequency rTMS (1Hz, 360 pulses) applied over the right dorsolateral prefrontal cortex combined with sham venlafaxine.

RESULTS

Responders (n=29) displayed lower retardation baseline scores (13.6±2.9) than non-responders (15.6±2.9; n=25; P=0.02). We also observed a significant difference between the numbers of ex-smokers in responders and non-responders groups; all ex-smokers (n=8) were responders to rTMS (P=0.005).

CONCLUSION

Low MADRS retardation factor and ex-smoker status is highly prevalent in responders to low frequency rTMS. Further studies are needed to investigate the predictive value of these factors.

Effects of theta-rhythm transcranial alternating current stimulation (4.5 Hz-tACS) in patients with clozapine-resistant negative symptoms of schizophrenia: a case series

Our aim was to assess the efficacy and safety of theta-rhythm transcranial Alternating Current Stimulation (4.5 Hz-tACS) in patients with clozapine-resistant symptoms of schizophrenia. In an open case series, 3 patients received 20 sessions of 4.5 Hz-tACS (20 min, 2 mA) applied over the dorsolateral prefrontal cortex. The patients exhibited a decrease of negative symptoms (-10 %), general symptoms (-18 %) and an improvement of insight into the illness (-25 %). 4.5 Hz-tACS might be a suitable alternative treatment for clozapine-resistant symptoms of schizophrenia.

Integrity of the arcuate fasciculus in patients with schizophrenia with auditory verbal hallucinations: A DTI-tractography study

Auditory verbal hallucinations (AVH) of schizophrenia are associated with a disrupted connectivity between frontal and temporoparietal language areas. We hypothesized that this dysconnectivity is underpinned by white matter abnormalities in the left arcuate fasciculus, the main fiber bundle connecting speech production and perception areas. We therefore investigated the relationship between AVH severity and the integrity of the arcuate fasciculus measured by diffusion tensor imaging (DTI) tractography in patients with schizophrenia.

Thirty-eight patients with treatment-resistant schizophrenia were included: 26 presented with daily severe treatment-resistant AVH, 12 reported prominent negative symptoms and no AVH. Fractional anisotropy (FA) was measured along the length of the left and right anterior arcuate fasciculi and severity of AVH was assessed using P3 PANSS item.

FA values were significantly higher in the left arcuate fasciculus in patients with AVH than in no AVH patients (F_(1,35) = 3.86; p = 0.05). No difference was observed in the right arcuate fasciculus. There was a significant positive correlation between FA value in the left arcuate fasciculus and the severity of AVH (r = 0.36; p = 0.02). No correlation was observed between FA values and PANSS total score suggesting a specific relationship between AVH severity and the left arcuate fasciculus integrity.

These results support the hypothesis of a relationship between left frontotemporal connectivity and AVH in patients with schizophrenia and suggest that whilst a disruption of frontotemporal connectivity might be present to ensure the emergence of AVH, more severe anatomical alterations may prevent the occurrence of AVH in patients with schizophrenia.

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Fractional anisotropy (FA) in the left arcuate fasciculus (AF) correlated with severity of hallucinations.

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Hallucinating patients had greater FA in the left AF than non-hallucinating patients.

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We did not find any association between hallucinations and FA in the right AF.

Transcranial Direct Current Stimulation for the Treatment of Refractory Symptoms of Schizophrenia. Current Evidence and Future Directions

Schizophrenia is a severe and frequent neuropsychiatric disorder. Despite antipsychotic medications, up to 30% of patients with schizophrenia still report disabling treatment-resistant symptoms. Transcranial direct current stimulation (tDCS) has been proposed as a novel method to alleviate such symptoms. Here, we review studies investigating the effects of tDCS on symptoms, cognition, brain activity and cortical plasticity in patients with schizophrenia. We provide an up-to-date and comprehensive overview of the use of tDCS in patients with schizophrenia. More specifically, we first present the effects of tDCS on treatment-resistant symptoms of schizophrenia. We report that tDCS applied over the frontotemporal regions reduced auditory hallucinations, with a mean 34% reduction of symptoms. Moreover, tDCS applied over both prefrontal cortices reduced negative symptoms and catatonia. We discuss the need for further sham-controlled studies to confirm these effects. Second, we present the impact of tDCS on cognitive functions in patients with schizophrenia. Positive effects of tDCS have been reported on learning, working memory, attention and source-monitoring. Third, we review the effects of tDCS on brain activity in patients with schizophrenia. Although only few studies investigated the effects of tDCS using neuroimaging technics, these studies are helpful at identifying the mechanisms of action of tDCS in schizophrenia. Fourth, we present tDCS studies on cortical plasticity showing reduced cortical plasticity in patients with schizophrenia that tDCS may beneficially modulate. Lastly, we discuss the safety aspects of tDCS in patients with schizophrenia and potential directions to improve efficacy for this clinical populations.

The application of tDCS in psychiatric disorders: a brain imaging view

Background

Transcranial direct current stimulation (tDCS) is a non-invasive, non-convulsive technique for modulating brain function. In contrast to other non-invasive brain stimulation techniques, where costs, clinical applicability, and availability limit their large-scale use in clinical practices, the low-cost, portable, and easy-to-use tDCS devices may overcome these restrictions.

Objective

Despite numerous clinical applications in large numbers of patients suffering from psychiatric disorders, it is not quite clear how tDCS influences the mentally affected human brain. In order to decipher potential neural mechanisms of action of tDCS in patients with psychiatric conditions, we focused on the combination of tDCS with neuroimaging techniques.

Design

We propose a contemporary overview on the currently available neurophysiological and neuroimaging data where tDCS has been used as a research or treatment tool in patients with psychiatric disorders.

Results

Over a reasonably short period of time, tDCS has been broadly used as a research tool to examine neuronal processes in the healthy brain. tDCS has also commonly been applied as a treatment application in a variety of mental disorders, with to date no straightforward clinical outcome and not always accompanied by brain imaging techniques.

Conclusion

tDCS, as do other neuromodulation devices, clearly affects the underlying neuronal processes. However, research on these mechanisms in psychiatric patients is rather limited. A better comprehension of how tDCS modulates brain function will help us to define optimal parameters of stimulation in each indication and may result in the detection of biomarkers in favor of clinical response.

Transcranial direct current stimulation in treatment-resistant obsessive-compulsive disorder: An open-label pilot study

BACKGROUND

Obsessive-compulsive disorder (OCD) is a severe mental illness. OCD symptoms are often resistant to available treatments. Abnormalities within the orbitofronto-striato-pallido-thalamic circuitry, especially orbitofrontal cortex (OFC) hyperactivity and cerebellar hypoactivity have been observed in patients. Non-invasive brain stimulation studies have indicated that transcranial direct current stimulation (tDCS) may be a useful alternative to alleviate treatment-resistant symptoms in various neuropsychiatric conditions.

METHODS

In an open-label pilot study, 8 patients with treatment-resistant OCD received 10 sessions (twice a day) of 2mA tDCS applied with the cathode over the left OFC and the anode over the right cerebellum. OCD (Y-BOCS and OCD-VAS) as well as depressive (MADRS) symptoms were measured 4 times: one time before tDCS and 3 times after (immediately after, 1 and 3months after the 10th tDCS session).

RESULTS

We reported a significant 26.4% (±15.8) decrease of Y-BOCS score (p=0.002). The beneficial effect lasted during the 3month follow-up. No effect of tDCS was observed on depressive symptoms. At end point, 5 out of 8 patients had a decrease of ≥25%; and 3 out of 8 patients had a decrease of ≥35% in Y-BOCS score. tDCS was well tolerated.

CONCLUSION

tDCS with the cathode placed over the left OFC combined with the anode placed over the right cerebellum is a suitable and safe approach to decrease OCD symptoms in patients with treatment-resistant OCD. Large scale randomized controlled studies are needed to confirm this promising result.

Deviations in cortex sulcation associated with visual hallucinations in schizophrenia

Hallucinations, and auditory hallucinations (AH) in particular, constitute the most typical and disabling schizophrenia symptoms. Although visual hallucinations (VH) have been largely neglected in psychiatric disorders, a recent review reported a 27% mean prevalence of VH in schizophrenia patients. The pathophysiology underlying VH in schizophrenia remains elusive. Several schizophrenia studies reported a significant effect of age on VH; therefore, we tested the hypothesis that the neurodevelopmental model of schizophrenia may explain VH occurrence. We analyzed cortex sulcation, a marker of brain development, in healthy controls (HCs) and two subgroups of carefully selected schizophrenia patients suffering from hallucinations: patients with only AH (that is, patients who never reported VH) and patients with audio-visual hallucinations (A+VH). Different cortical sulcation and left-right sulcal asymmetry were found between A+VH and AH patients, with decreased sulcation in both A+VH and AH patients in comparison with the HCs. Although a specific association between VH and neurodegenerative mechanisms, for example, in Body-Lewy Dementia or Parkinson's Disease, has previously been reported in the literature, the current study provides the first neuroimaging evidence of an association between VH and neurodevelopmental mechanisms.

Transcranial direct current stimulation in psychiatric disorders

The interest in non-invasive brain stimulation techniques is increasing in recent years. Among these techniques, transcranial direct current stimulation (tDCS) has been the subject of great interest among researchers because of its easiness to use, low cost, benign profile of side effects and encouraging results of research in the field. This interest has generated several studies and randomized clinical trials, particularly in psychiatry. In this review, we provide a summary of the development of the technique and its mechanism of action as well as a review of the methodological aspects of randomized clinical trials in psychiatry, including studies in affective disorders, schizophrenia, obsessive compulsive disorder, child psychiatry and substance use disorder. Finally, we provide an overview of tDCS use in cognitive enhancement as well as a discussion regarding its clinical use and regulatory and ethical issues. Although many promising results regarding tDCS efficacy were described, the total number of studies is still low, highlighting the need of further studies aiming to replicate these findings in larger samples as to provide a definite picture regarding tDCS efficacy in psychiatry.

Regulatory Considerations for the Clinical and Research Use of Transcranial Direct Current Stimulation (tDCS): review and recommendations from an expert panel

The field of transcranial electrical stimulation (tES) has experienced significant growth in the past 15 years. One of the tES techniques leading this increased interest is transcranial direct current stimulation (tDCS). Significant research efforts have been devoted to determining the clinical potential of tDCS in humans. Despite the promising results obtained with tDCS in basic and clinical neuroscience, further progress has been impeded by a lack of clarity on international regulatory pathways. We therefore convened a group of research and clinician experts on tDCS to review the research and clinical use of tDCS. In this report, we review the regulatory status of tDCS, and we summarize the results according to research, off-label and compassionate use of tDCS in the following countries: Australia, Brazil, France, Germany, India, Iran, Italy, Portugal, South Korea, Taiwan and United States. Research use, off label treatment and compassionate use of tDCS are employed in most of the countries reviewed in this study. It is critical that a global or local effort is organized to pursue definite evidence to either approve and regulate or restrict the use of tDCS in clinical practice on the basis of adequate randomized controlled treatment trials.