Transcranial direct current stimulation as an additional treatment to selective serotonin reuptake inhibitors in adults with major depressive disorder in Germany (DepressionDC): a triple-blind, randomised, sham-controlled, multicentre trial.

BACKGROUND: Transcranial direct current stimulation (tDCS) has been proposed as a feasible treatment for major depressive disorder (MDD). However, meta-analytic evidence is heterogenous and data from multicentre trials are scarce. We aimed to assess the efficacy of tDCS versus sham stimulation as an additional treatment to a stable dose of selective serotonin reuptake inhibitors (SSRIs) in adults with MDD. METHODS: The DepressionDC trial was triple-blind, randomised, and sham-controlled and conducted at eight hospitals in Germany. Patients being treated at a participating hospital aged 18-65 years were eligible if they had a diagnosis of MDD, a score of at least 15 on the Hamilton Depression Rating Scale (21-item version), no response to at least one antidepressant trial in their current depressive episode, and treatment with an SSRI at a stable dose for at least 4 weeks before inclusion; the SSRI was continued at the same dose during stimulation. Patients were allocated (1:1) by fixed-blocked randomisation to receive either 30 min of 2 mA bifrontal tDCS every weekday for 4 weeks, then two tDCS sessions per week for 2 weeks, or sham stimulation at the same intervals. Randomisation was stratified by site and baseline Montgomery-Åsberg Depression Rating Scale (MADRS) score (ie, <31 or ≥31). Participants, raters, and operators were masked to treatment assignment. The primary outcome was change on the MADRS at week 6, analysed in the intention-to-treat population. Safety was assessed in all patients who received at least one treatment session. The trial was registered with ClinicalTrials.gov (NCT02530164). FINDINGS: Between Jan 19, 2016, and June 15, 2020, 3601 individuals were assessed for eligibility. 160 patients were included and randomly assigned to receive either active tDCS (n=83) or sham tDCS (n=77). Six patients withdrew consent and four patients were found to have been wrongly included, so data from 150 patients were analysed (89 [59%] were female and 61 [41%] were male). No intergroup difference was found in mean improvement on the MADRS at week 6 between the active tDCS group (n=77; -8·2, SD 7·2) and the sham tDCS group (n=73; -8·0, 9·3; difference 0·3 [95% CI -2·4 to 2·9]). Significantly more participants had one or more mild adverse events in the active tDCS group (50 [60%] of 83) than in the sham tDCS group (33 [43%] of 77; p=0·028). INTERPRETATION: Active tDCS was not superior to sham stimulation during a 6-week period. Our trial does not support the efficacy of tDCS as an additional treatment to SSRIs in adults with MDD. FUNDING: German Federal Ministry of Education and Research.

TDCS at home for depressive disorders: an updated systematic review and lessons learned from a prematurely terminated randomized controlled pilot study.

The application of transcranial direct current stimulation (tDCS) at home for the treatment of major depressive disorder (MDD) is the subject of current clinical trials. This is due to its positive safety profile, cost-effectiveness, and potential scalability for a wide outreach in clinical practice. Here, we provide a systematic review of the available studies and also a report on the results of a randomized controlled trial (RCT) on tDCS at home for the treatment of MDD. This trial had to be prematurely terminated due to safety concerns. The HomeDC trial is a double-blinded, placebo-controlled, parallel-group study. Patients with MDD (DSM-5) were randomized to active or sham tDCS. Patients conducted tDCS at home for 6 weeks with 5 sessions/week (30 min at 2 mA) anode over F3, cathode over F4. Sham tDCS resembled active tDCS, with ramp-in and ramp-out periods, but without intermittent stimulation. The study was prematurely terminated due to an accumulation of adverse events (AEs, skin lesions), so that only 11 patients were included. Feasibility was good. Safety monitoring was not sufficient enough to detect or prevent AEs within an appropriate timeframe. Regarding antidepressant effects, the reduction in depression scales over time was significant. However, active tDCS was not superior to sham tDCS in this regard. Both the conclusions from this review and the HomeDC trial show that there are several critical issues with the use of tDCS at home that need to be addressed. Nevertheless the array of transcranial electric simulation (TES) methods that this mode of application offers, including tDCS, is highly interesting and warrants further investigation in high quality RCTs. TRIAL REGISTRATION: www. CLINICALTRIALS: gov . TRIAL REGISTRATION NUMBER: NCT05172505. Registration date: 12/13/2021, https://clinicaltrials.gov/ct2/show/NCT05172505 . *Consider, if feasible to do so, reporting the number of records identified from each database or register searched (rather than the total number across all databases/registers) **If automation tools were used, indicate how many records were excluded by a human and how many were excluded by automation tools From: Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ 2021;372:n71. https://doi.org/10.1136/bmj.n71 . For more information, visit: http://www.prisma-statement.org/.

Transcranial direct current stimulation combined with a brief intervention for smoking cessation: a randomized double-blind clinical trial.

Non-invasive brain stimulation methods are currently being evaluated for treatment of addictive disorders. Some evidence indicates that modulating left and right prefrontal brain activity by transcranial direct current stimulation (tDCS) can reduce craving and relapse rates in tobacco addiction. Therefore, this study investigated the effects of active and sham tDCS as an add-on treatment to a standardized brief intervention for smoking cessation. This randomized, double-blind study included 36 participants (22 women and 14 men) with nicotine dependence according to ICD-10 criteria. At five visits on alternate days, participants underwent a 20-min active or sham tDCS over the left dorsolateral prefrontal cortex and subsequently participated in a 10-min brief intervention for smoking cessation. Patients were followed up after 3 months. On each treatment day and at follow-up, abstinence was assessed as the smoking status nonsmoker and craving was assessed with the German version of the Questionnaire on Smoking Urges. At each visit, the number of cigarettes smoked per day was recorded and carbon monoxide in expired air and cotinine in saliva were measured. At follow-up, a study-specific questionnaire was used to assess tobacco use. All 36 participants completed the treatment sessions, but one participant in each group was lost to follow-up. Abstinence rates were not significantly different between the groups at any of the study visits, but craving was significantly lower in the active group at tDCS session 5 compared with session 1. tDCS combined with a brief intervention may support smoking cessation, but studies need to evaluate whether longer and more intensive treatment can achieve significant, sustainable effects.

[Alexithymia in Multiple Sclerosis - Narrative Review]. / Alexithymie bei Multipler Sklerose ­ eine narrative Übersicht.

Alexithymia is a multidimensional construct of personality implicating difficulties in identifying and describing another's feelings, and externally oriented thinking. It is broadly reported in psychiatric patients but has gained little attention regarding its occurrence and pathophysiology in multiple sclerosis (MS). This narrative review aims to address prevalence, etiology, neurobiological, and clinical findings of alexithymia. The prevalence of alexithymia in MS ranges from 10 to 53%. There seems to be an association with anxiety, depression, fatigue, and some aspects of social cognition, while the relationship with clinical and classical cognitive variables was rarely evaluated. Only a few studies referred to its pathophysiology assuming an aberrant interhemispheric transfer or regional cerebral abnormalities. The prevalence of alexithymia in MS and the potential negative impact on quality of life and interpersonal communication could severely impact clinical MS management and a screnning for these factors should be mandatory. Thus, further evaluation is needed concerning its relationship with clinical, emotional, and cognitive confounders. Large-scale studies employing neuroimaging techniques are needed for a better understanding of the neural underpinnings of this MS feature.

[Transcranial electrical brain stimulation methods for treatment of negative symptoms in schizophrenia]. / Transkranielle elektrische Hirnstimulationsverfahren zur Behandlung der Negativsymptomatik bei Schizophrenie.

In recent years noninvasive brain stimulation (NIBS) applications have emerged as a third and novel treatment option alongside psychopharmacology and psychotherapy in the treatment of mental diseases. It is assumed that NIBS could represent a supplement or (in some indications) even replacement to established therapeutic strategies, e.g. in disorders with high resistance to current treatment regimens, such as negative symptoms or cognitive impairments in schizophrenia. Although positive symptoms in schizophrenia can be treated sufficiently with antipsychotic drugs, patients with negative symptoms frequently suffer from persistent lack of impetus, cognitive decline, social withdrawal and loss of global functioning in the activities of daily life; however, in these cases, current treatment strategies exert only moderate effects, and new treatment options are urgently needed. This review article provides a summary of the clinical effects of new electrical NIBS methods, e.g. transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), and transcranial random noise stimulation (tRNS) for the treatment of negative symptoms in schizophrenia. These new NIBS methods could help restore the disrupted neuronal networks and improve disturbed connectivity, especially of the left dorsolateral prefrontal cortex and left temporoparietal junction. Promising results are reported for the treatment of negative symptoms with tDCS, tACS and tRNS and could thus represent new therapeutic options in the treatment of schizophrenia.

Bifrontal transcranial direct current stimulation modulates fatigue in multiple sclerosis: a randomized sham-controlled study.

Fatigue is a frequent and debilitating symptom in patients with central nervous system diseases. Up to 90% of patients with multiple sclerosis (MS) suffer from fatigue that drastically affects the quality of life. MS patients also complain of anxiety and depressive symptoms and these three manifestations tend to cluster together in this clinical population. The objective of this work was to assess the effects of transcranial direct stimulation (tDCS), a noninvasive brain stimulation technique, on fatigue as well as anxiety and depressive symptoms. Eleven fatigued MS patients randomly received two blocks (active and sham tDCS) of five consecutive daily sessions of bifrontal tDCS (anode/cathode over the left/right prefrontal cortices, respectively) in a crossover manner, separated by a 3-week washout interval. Evaluation took place at day 1, day 5 (right after each block) and 1 week later. Active but not sham tDCS resulted in a significant improvement of fatigue at day 5 (p < 0.05), an effect that seems to last at least 1 week following the stimulation (p = 0.05). Active tDCS also significantly improved anxiety symptoms, but the effect emerged 1 week later (p < 0.05). No significant effects were obtained regarding depression (p > 0.05). Bifrontal tDCS seems to modulate fatigue in PwMS. The observed anxiolytic effects could constitute delayed after effects of tDCS or might be mediated by fatigue improvement. These findings merit to be addressed in large-scale controlled trials.

tDCS for auditory verbal hallucinations in a case of schizophrenia and left frontal lesion: efield simulation and clinical results.

Transcranial direct current stimulation (tDCS) has been explored for treatment of several neuropsychiatric disorders. For tDCS use in structural brain lesions there is some evidence from motor stroke rehabilitation and post-stroke depression. Here we report the application of tDCS in a woman previously diagnosed with schizophrenia presenting refractory auditory verbal hallucinations and left prefrontal tissue lesion. Treatment with 20 left fronto-temporal tDCS had no effect on psychiatric symptoms and neuropsychological evaluation. An ex-post electric field simulation and calculation of dorsolateral prefrontal cortex activation showed lower activation in this patient compared to a matched non-lesioned schizophrenia, and healthy control brain.

Gamma transcranial alternating current stimulation (γtACS) in obsessive-compulsive disorder: a case report

Die Zwangsstörung hat oftmals einen chronischen Verlauf mit Therapieresistenz gegenüber Psychopharmakotherapie und Psychotherapie. Neue nichtinvasive Hirnstimulationsverfahren könnten helfen, Zwangssymptome zu vermindern. In diesem Fallbericht wird die Behandlung einer Patientin mit Zwangsstörung dargestellt, die mit 10 transkraniellen Wechselstromstimulationen in Gamma-Frequenz (40 Hz) im Rahmen eines Heilversuchs behandelt wurde. Die Yale-Brown Obsessive-Compulsive Scale verminderte sich von 70 auf 59 Punkte, und die Hamilton Depression Rating Scale sank von 25 auf 12 Punkte. Daneben konnte eine Verbesserung des Regensburger Wortflüssigkeitstests, des Pfadfindertests und eines computergestützten n-back-Tests verzeichnet werden. Eine Hypothese für die Verbesserung der Zwangsstörung durch Gamma-Wechselstromstimulation könnte eine Auswirkung auf die bei psychischen Erkrankungen (Depression, Zwangsstörung) veränderte alpha-Frequenz sein. Der hier vorgestellte Fall bestätigt die Ergebnisse einer früheren Fallserie und gibt Anlass zur weiteren Untersuchung dieses Verfahrens.

[Transcranial direct current stimulation (tDCS) for obsessive-compulsive disorder: A new treatment option?] / Transkranielle Gleichstromstimulation (tDCS) bei Zwangsstörung: Eine neue Therapieoption?

More than 40 % of patients with obsessive-compulsive disorder (OCD) do not respond to established treatments despite advances in psychopharmacology and psychotherapy. Since a couple of years, non-invasive brain stimulation techniques gain importance in the treatment of psychiatric disorders. Transcranial direct current stimulation (tDCS) uses weak constant direct current to modulate neuronal activation and changes the function of neuronal networks. This technique is recently investigated for the improvement of treatment resistant OCD symptoms. In this review we give a concise overview over the current state of the art and delineate further directions of tDCS application in OCD. The search in the NIH database pubmed and further manual search revealed nine case reports, three open label studies and one controlled study with two active arms. There is no sham controlled study yet. A total of 78 patients received active tDCS with a large variety of different electrode placements, with main target over dorsolateral prefrontal cortex, orbitofrontal cortex, and (pre-)supplementary motor areas. Although stimulation parameters were highly heterogeneous, reported cases show not only an improvement of OCD symptoms, but also an improvement of depression and anxiety symptoms in patients with treatment resistant OCD. This evidence is limited by the lack of sham-controlled studies and needs confirmation in larger studies.

Home Use, Remotely Supervised, and Remotely Controlled Transcranial Direct Current Stimulation: A Systematic Review of the Available Evidence.

OBJECTIVES: Transcranial direct current stimulation (tDCS) is gaining growing importance in the treatment of neurological and psychiatric disorders and is currently investigated for home-based and remotely supervised applications. METHODS: Here, we systematically review the available evidence from a database search (PubMed, ICTRP, clinicaltrials.gov) from January 2000 to May 2017. RESULTS: We detected 22 original research papers, trial protocols or trial registrations dealing with tDCS as an add-on intervention to cognitive or physiotherapeutic intervention. Overall, study samples are small; many studies are single-blinded and focus on feasibility and safety. There are two guideline papers setting basic requirements for clinical trials. CONCLUSIONS: Further research needs to focus on home-based treatment from different viewpoints, that is, safety, technical monitoring, reproducibility of repeated applications, feasibility of combined interventions and systematic assessment of efficacy, and safety in large randomized controlled clinical trials (RCTs). However, remotely controlled and supervised tDCS for home use represents a promising approach for widespread use of noninvasive brain stimulation (NIBS) in clinical care.

Vagus nerve stimulation in psychiatry: a systematic review of the available evidence.

Invasive and non-invasive vagus nerve stimulation (VNS) is a promising add-on treatment for treatment-refractory depression, but is also increasingly evaluated for its application in other psychiatric disorders, such as dementia, schizophrenia, somatoform disorder, and others. We performed a systematic review aiming to give a detailed overview of the available evidence of the efficacy of VNS for the treatment of psychiatric disorders. Data derived from animal models, experimental trials without health-related outcomes, case reports, single-session studies, and reviews were excluded. From 1292 publications, 33 records were included for further analyses: 25 focused on VNS as treatment of unipolar or bipolar major depressive disorder and one investigated the neurocognitive improvement after VNS in major depressive disorder. Seven focused on the improvement of cognitive function in Alzheimer´s disease, improvement of schizophrenia symptoms, treatment of obsessive compulsive disorder (OCD), panic disorder (PD) and post-traumatic stress disorder (PTSD), treatment resistant rapid-cycling bipolar disorder, treatment of fibromyalgia, and Prader-Willi syndrome. A total of 29 studies used invasive VNS, while four studies used non-invasive, transcutaneous VNS. Only 7 out of 33 studies investigated conditions other than affective disorders. The efficacy data of VNS in affective disorders is promising, whereas more in controlled and naturalistic studies are needed. In other conditions like schizophrenia, Alzheimer's disease, OCD, PD, PTSD, and fibromyalgia, either no effects or preliminary data on efficacy were reported. At this point, no final conclusion can be made regarding the efficacy of VNS to improve symptoms in psychiatric disorders other than in affective disorders.

Prefrontal tDCS and sertraline in obsessive compulsive disorder: a case report and review of the literature.

Obsessive-compulsive (OC) disorder is a disabling disorder resulting in tremendous individual and social burden. It has a large overlap with depression and anxiety disorders and shows treatment resistance in a relevant proportion of patients. Since a couple of years, different noninvasive brain stimulation methods have been investigated to improve OC symptoms. The application of transcranial direct current stimulation (tDCS) has shown inconsistent results which can probably be attributed to a lack in randomized controlled trials with adequate sample size. Anodal stimulation of pre-supplementary motor areas has shown promising results, and there is also sparse data on orbitofrontal and prefrontal stimulation. Here, we provide the first report on a patient with treatment-refractory OC disorder treated with sertraline and an enhanced prefrontal tDCS protocol (twice per day, 10 days) with a classic left-anodal/right cathodal montage, experiencing a 22% reduction of OC symptoms as well as reduction in depression (-10%) and anxiety symptoms (-21%). Due to multifactorial origin of OC disorder and the variety of brain circuits involved, there are probably multiple approaches for brain stimulation regarding site, polarity, and frequency to be assessed in future studies.

Driving skills in unmedicated first- and recurrent-episode schizophrenic patients.

The present study was designed to examine driving skills according to regulations of the German guidelines for road and traffic safety in unmedicated schizophrenic inpatients. A total of 13 first-episode (FES) and 13 recurrent-episode (RES) schizophrenic inpatients were included in the analysis and compared with a group of 20 healthy controls (HC). Data were collected with the computerised Wiener Testsystem measuring visual perception, reactivity and stress tolerance, concentration and vigilance. Analysis of data indicates that a great proportion (58 %) of schizophrenic patients were impaired in psychomotor functions related to driving skills. FES and RES significantly differed with respect to driving ability with a greater proportion in the FES (38 %) showing severe impairments when compared with RES (25 %). Differences with respect to HC performance were most pronounced in concentration and for the FES additionally in visual perception. Analysis of our data indicates that a great proportion of schizophrenic patients are impaired in psychomotor functions related to driving skills that cannot be attributed to adverse side effects of psychopharmacological treatment. Besides, we cannot confirm a chronical decline of psychomotor functions related to driving skills at least in the early course of schizophrenic illness.

Prefrontal transcranial direct current stimulation (tDCS) as treatment for major depression: study design and methodology of a multicenter triple blind randomized placebo controlled trial (DepressionDC).

Transcranial direct current stimulation (tDCS) has been proposed as novel treatment for major depressive disorder (MDD) based on clinical pilot studies as well as randomized controlled monocentric trials. The DepressionDC trial is a triple-blind (blinding of rater, operator and patient), randomized, placebo controlled multicenter trial investigating the efficacy and safety of prefrontal tDCS used as additive treatment in MDD patients who have not responded to selective serotonin reuptake inhibitors (SSRI). At 5 study sites, 152 patients with MDD receive a 6-weeks treatment with active tDCS (anode F3 and cathode F4, 2 mA intensity, 30 min/day) or sham tDCS add-on to a stable antidepressant medication with an SSRI. Follow-up visits are at 3 and 6 months after the last tDCS session. The primary outcome measure is the change of the Montgomery-Asberg Depression Rating Scale (MADRS) scores at week 6 post-randomisation compared to baseline. Secondary endpoints also cover other psychopathological domains, and a comprehensive safety assessment includes measures of cognition. Patients undergo optional investigations comprising genetic testing and functional magnetic resonance imaging (fMRI) of structural and functional connectivity. The study uses also an advanced tDCS technology including standard electrode positioning and recording of technical parameters (current, impedance, voltage) in every tDCS session. Aside reporting the study protocol here, we present a novel approach for monitoring technical parameters of tDCS which will allow quality control of stimulation and further analysis of the interaction between technical parameters and clinical outcome. The DepressionDC trial will hopefully answer the important clinical question whether prefrontal tDCS is a safe and effective antidepressant intervention in patients who have not sufficiently responded to SSRIs. TRIAL REGISTRY: ClinicalTrials.gov Identifier NCT0253016.

[Facial emotion recognition, theory of mind and empathy in multiple sclerosis]. / Emotionserkennung, Theory of Mind und Empathie bei Multipler Sklerose.

Multiple sclerosis (MS), a chronic progressive inflammatory disease of the central nervous system, causes frequent disability, mood disorders, fatigue, and cognitive dysfunction. As a part of the last, social cognition is frequently disturbed in MS patients. It comprises empathy and social perception of emotions from facial, bodily and vocal cues. Social cognitive deficits worsen affect decoding, interpersonal relationship, and quality of life. Despite the impact of these deficits on global functioning, only a small number of studies have investigated its correlations and overlaps with MS symptoms. This review focuses on the definition and anatomy of social cognition and draws attention to findings of neuropsychological and neuroimaging studies on social cognitive performance in MS.Results of the available studies show that social cognitive deficits are already measurable in early stages of MS. Over time course of the disease, neuropsychological and neuroimaging studies show an increase of disease burden and social and non-social cognitive impairment following the hypothesis of a disconnection syndrome resulting from gray and white matters lesions. These structural changes might exceed a threshold of compensatory restorative and neuroplasticity mechanisms and finally lead to deficits in social cognition. Considering this burden in social functioning, a further assessment of sociocognitive deficits in MS is urgently needed to provide specific therapeutic approaches and to improve quality of life.

[Multiple sclerosis fatigue, its neural correlates, and its modulation with tDCS]. / Fatigue bei Multipler Sklerose: Neuronale Korrelate und Möglichkeiten nicht-invasiver Hirnstimulation mit tDCS.

Multiple sclerosis (MS) is a chronic progressive and inflammatory disease of the central nervous system and causes high rates of non-traumatic disability in young adults. Fatigue is frequently reported by a major part of patients during the disease course and dramatically increases the burden of illness. Despite the high prevalence of fatigue and its enormous impact on quality of life, its pathophysiological mechanisms are still unclear. Its etiology is multifactorial and complex, and is usually classified into 'primary' fatigue resulting from the pathological brain changes versus 'secondary' fatigue following disease symptoms, sleep disturbances, mood disorders, and side effects of medication. Hypotheses concerning the pathophysiology of this symptom are based on radiological, physiological, and endocrine data. It has been suggested that fatigue refers to structural and functional changes in a variety of neuronal networks. Over the past years, non-invasive brain stimulation methods were used to modulate brain function, especially transcranial direct current stimulation (tDCS) has proven to impact neuronal connectivity; however evidence is still sparse due to the pilot character of the studies. In this review we aim at discussing the neuronal correlates of fatigue and the potential influence of tDCS in the modulation of the symptoms.

Transcranial direct current stimulation for acute major depressive episodes: meta-analysis of individual patient data.

BACKGROUND: Transcranial direct current stimulation (tDCS) is a non-pharmacological intervention for depression. It has mixed results, possibly caused by study heterogeneity. AIMS: To assess tDCS efficacy and to explore individual response predictors. METHOD: Systematic review and individual patient data meta-analysis. RESULTS: Data were gathered from six randomised sham-controlled trials, enrolling 289 patients. Active tDCS was significantly superior to sham for response (34% v. 19% respectively, odds ratio (OR) = 2.44, 95% CI 1.38-4.32, number needed to treat (NNT) = 7), remission (23.1% v. 12.7% respectively, OR = 2.38, 95% CI 1.22-4.64, NNT = 9) and depression improvement (B coefficient 0.35, 95% CI 0.12-0.57). Mixed-effects models showed that, after adjustment for other predictors and confounders, treatment-resistant depression and higher tDCS 'doses' were, respectively, negatively and positively associated with tDCS efficacy. CONCLUSIONS: The effect size of tDCS treatment was comparable with those reported for repetitive transcranial magnetic stimulation and antidepressant drug treatment in primary care. The most important parameters for optimisation in future trials are depression refractoriness and tDCS dose.

Transcranial direct current stimulation in children and adolescents: a comprehensive review.

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method that has shown promising results in various neuropsychiatric disorders in adults. This review addresses the therapeutic use of tDCS in children and adolescents including safety, ethical, and legal considerations. There are several studies addressing the dosage of tDCS in children and adolescents by computational modeling of electric fields in the pediatric brain. Results suggest halving the amperage used in adults to obtain the same peak electric fields, however, there are some studies reporting on the safe application of tDCS with standard adult parameters in children (2 mA; 20-30 min). There are several randomized placebo controlled trials suggesting beneficial effects of tDCS for the treatment of cerebral palsy. For dystonia there are mixed data. Some studies suggest efficacy of tDCS for the treatment of refractory epilepsy, and for the improvement of attention deficit/hyperactivity disorder and autism. Interestingly, there is a lack of data for the treatment of childhood and adolescent psychiatric disorders, i.e., childhood onset schizophrenia and affective disorders. Overall, tDCS seems to be safe in pediatric population. More studies are needed to confirm the preliminary encouraging results; however, ethical deliberation has to be weighed carefully for every single case.

tDCS for the treatment of depression: a comprehensive review.

Transcranial direct current stimulation (tDCS) has been investigated for the treatment of major depressive disorders in recent years. Here, we review the implications of current research for the clinical use of tDCS in the treatment of major depressive disorder. Meta-analyses, randomized, placebo-controlled clinical trials, open-label trials, case reports and review articles were identified through a systematic search of the literature database of the National Institutes of Health (USA). Available articles were evaluated with regard to their clinical relevance. Results of tDCS efficacy are inconsistent due to the small sample sizes, the heterogeneous patient samples and the partially high treatment resistance in some studies. Overall, tDCS has very low side effects. Meta-analyses suggest some efficacy of tDCS in the treatment of acute depressive disorder with moderate effect size, and low efficacy in treatment-resistant depression. A general statement about the efficacy of tDCS as a therapeutic tool in major depression seems to be premature. tDCS is considered as a safe therapeutic option and is associated with only minor side effects. The effectiveness of tDCS decreases with resistance to treatment. Psychotropic drugs may attenuate or amplify its effects. The use of 2 mA current strength over 20 min per day over a short time span can be considered as safe.