Effects of Dual Task Training and Transcranial Direct Current Stimulation in Children with Spastic Cerebral Palsy: A Pilot Randomized Control Trial

OBJECTIVE

Compare the effectiveness of active and sham transcranial direct current stimulation (tDCS) during the training of a dual task in children with spastic cerebral palsy (CP).

METHODS

Thirty children with CP were submitted to ten sessions of either active (n = 15) or sham (n = 15) tDCS over the motor cortex for 20 minutes during the training of a dual task. Pre-intervention, post-intervention and follow-up evaluations involved measures of functional performance, intellectual performance, functional mobility and cortical excitability.

RESULTS

The combination of active tDCS and dual task training led to improvements in functional mobility as well as functional and intellectual performances one month after the end of the intervention.

CONCLUSION

The combination of active tDCS and dual task training demonstrated promising effects for children with spastic CP.

Examining the neural mechanisms of rTMS: a naturalistic pilot study of acute and serial effects in pharmacoresistant depression

Introduction

Previous studies have demonstrated the effectiveness of therapeutic repetitive transcranial magnetic stimulation (rTMS) to treat pharmacoresistant depression. Nevertheless, these trials have primarily focused on the therapeutic and neurophysiological effects of rTMS following a long-term treatment course. Identifying brain-based biomarkers of early rTMS therapeutic response remains an important unanswered question. In this pilot study, we examined the effects of rTMS on individuals with pharmacoresistant depression using a graph-based method, called Functional Cortical Networks (FCN), and serial electroencephalography (EEG). We hypothesized that changes in brain activity would occur early in treatment course.

Methods

A total of 15 patients with pharmacoresistant depression underwent five rTMS sessions (5Hz over the left dorsolateral prefrontal cortex, 120%MT, up to 4,000 pulses/session). Five participants received additional rTMS treatment, up to 40 sessions. Resting EEG activity was measured at baseline and following every five sessions, using 64-channel EEG, for 10 minutes with eyes closed. An FCN model was constructed using time-varying graphs and motif synchronization. The primary outcome was acute changes in weighted-node degree. Secondary outcomes included serial FFT-based power spectral analysis and changes in depressive symptoms measured by the 9-Item Patient Health Questionnaire (PHQ-9) and the 30-item Inventory of Depressive Symptoms-Self Report (IDS-SR).

Results

We found a significant acute effect over the left posterior area after five sessions, as evidenced by an increase in weighted-node degree of 37,824.59 (95% CI, 468.20 to 75,180.98) and a marginal enhancement in the left frontal region (t (14) = 2.0820, p = 0.056). One-way repeated measures ANOVA indicated a significant decrease in absolute beta power over the left prefrontal cortex (F (7, 28) = 2.37, p = 0.048) following ten rTMS sessions. Furthermore, a significant clinical improvement was observed following five rTMS sessions on both PHQ-9 (t (14) = 2.7093, p = 0.017) and IDS-SR (t (14) = 2.5278, p = 0.024) and progressed along the treatment course.

Discussion

Our findings suggest that FCN models and serial EEG may contribute to a deeper understanding of mechanisms underlying rTMS treatment. Additional research is required to investigate the acute and serial effects of rTMS in pharmacoresistant depression and assess whether early EEG changes could serve as predictors of therapeutic rTMS response.

Heart Rate Variability Features as Predictors of Intermittent Theta-Burst Stimulation Response in Posttraumatic Stress Disorder

BACKGROUND

Posttraumatic stress disorder (PTSD) is associated with autonomic dysfunction as indicated by deficits in the sympathetic and parasympathetic nervous systems. These abnormalities are expressed as elevated heart rate and reduced heart rate variability (HRV), respectively. Intermittent theta-burst stimulation (iTBS), a form of transcranial magnetic stimulation, has demonstrated effectiveness in PTSD. Nevertheless, it remains unclear whether HRV may be an iTBS biomarker for PTSD and whether iTBS impacts autonomic activity.

MATERIALS AND METHODS

Fifty veterans with PTSD participated in a randomized controlled trial, receiving ten daily sessions of sham-controlled iTBS (right dorsolateral prefrontal cortex, 1800 pulses/day, 80% active motor threshold, 9.5 min). With a usable dataset (N = 47), HRV parameters were assessed as predictors of clinical response immediately after stimulation. iTBS effects on autonomic response (mean RR interval, root mean square of successive differences [RMSSD], total power [TP], and low-frequency/high-frequency [LF/HF] ratio) were evaluated using an ultra-short approach.

RESULTS

TP and RMSSD were significant predictors of acute clinical response to iTBS. Individuals with higher TP had better response to iTBS with improved symptoms on the Clinician-Administered PTSD Scale (rs = -0.58, p = 0.004), and higher functionality on the Social and Occupational Function Scale (rs = 0.43, p = 0.04). Similarly, higher RMSSD was associated with superior outcomes (rs = -0.44, p = 0.04). No other significant changes in HRV metrics were observed (p ≥ 0.05).

CONCLUSIONS

Our findings indicate that autonomic activity is a potential low-cost and technically simple predictive biomarker of iTBS response in PTSD. Less autonomic dysfunction was associated with superior clinical improvements with iTBS. Future studies might consider HRV acquisition during iTBS, as well as prospective testing of these findings in patients with elevated hyperarousal.

Burnout and Moral Injury Among Consultation-Liaison Psychiatry Trainees

Burnout and moral injury within medicine have steadily increased over the last decades, especially among those providing care during the COVID-19 pandemic. The term burnout has been used to describe clinician distress and a syndrome of emotional exhaustion, a diminished sense of personal accomplishment, and depersonalization. Burnout has a significant impact on both job performance and patient care. Moral injury occurs when external circumstances interact with a person's cherished beliefs and standards. When the tension between them cannot be reconciled, the felt integrity of the individual is disrupted and the person experiences distress. The consultative aspect in consultation-liaison psychiatry (CLP) presents challenges that may predispose the young clinician to burnout and moral injury, especially during fellowship training. CLP psychiatrists also have a liaison role that could catalyze systemlevel change to enhance the mental well-being of their colleagues. This article reviews clinically relevant psychodynamic aspects of burnout and moral injury during CLP training. In addition, the authors propose strategies to enhance career growth and prevent and address moral injury during training to generate fulfilling professional development.

Transcranial magnetic stimulation for post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is a debilitating psychiatric disorder. While current treatment options are effective for some, many individuals fail to respond to first-line psychotherapies and pharmacotherapy. Transcranial magnetic stimulation (TMS) has emerged over the past several decades as a noninvasive neuromodulatory intervention for psychiatric disorders including depression, with mounting evidence for its safety, tolerability, and efficacy in treating PTSD. While several meta-analyses of TMS for PTSD have been published to date showing large effect sizes on PTSD overall, there is marked variability between studies, making it difficult to draw simple conclusions about how best to treat patients. The following review summarizes over 20 years of the existing literature on TMS as a PTSD treatment, and includes nine randomized controlled trials and many other prospective studies of TMS monotherapy, as well as five randomized controlled trials investigating TMS combined with psychotherapy. While the majority of studies utilize repetitive TMS targeted to the right dorsolateral prefrontal cortex (DLPFC) at low frequency (1 Hz) or high frequency (10 or 20 Hz), others have used alternative frequencies, targeted other regions (most commonly the left DLPFC), or trialed different stimulation protocols utilizing newer TMS modalities such as synchronized TMS and theta-burst TMS (TBS). Although it is encouraging that positive outcomes have been shown, there is a paucity of studies directly comparing available approaches. Biomarkers, such as functional imaging and electroencephalography, were seldomly incorporated yet remain crucial for advancing our knowledge of how to predict and monitor treatment response and for understanding mechanism of action of TMS in this population. Effects on PTSD are often sustained for up to 2-3 months, but more long-term studies are needed in order to understand and predict duration of response. In short, while TMS appears safe and effective for PTSD, important steps are needed to operationalize optimal approaches for patients suffering from this disorder.

Repetitive Transcranial Magnetic Stimulation for Treatment-Resistant Depression: Recent Critical Advances in Patient Care

PURPOSE

Transcranial magnetic stimulation (TMS) is an evidence-based treatment for pharmacoresistant major depressive disorder (MDD). In the last decade, the field has seen significant advances in the understanding and use of this new technology. This review aims to describe the large, randomized controlled studies leading to the modern use of rTMS for MDD. It also includes a special section briefly discussing the use of these technologies during the COVID-19 pandemic.

RECENT FINDINGS

Several new approaches and technologies are emerging in this field, including novel approaches to reduce treatment time and potentially yield new approaches to optimize and maximize clinical outcomes. Of these, theta burst TMS now has evidence indicating it is non-inferior to standard TMS and provides significant advantages in administration. Recent studies also indicate that neuroimaging and related approaches may be able to improve TMS targeting methods and potentially identify those patients most likely to respond to stimulation.

SUMMARY

While new data is promising, significant research remains to be done to individualize and optimize TMS procedures. Emerging new approaches, such as accelerated TMS and advanced targeting methods, require additional replication and demonstration of real-world clinical utility. Cautious administration of TMS during the pandemic is possible with careful attention to safety procedures.

Use of transcranial direct current stimulation for the treatment of auditory hallucinations of schizophrenia - a systematic review

INTRODUCTION

Auditory hallucinations are defined as experiences of auditory perceptions in the absence of a provoking external stimulus. They are the most prevalent symptoms of schizophrenia with high capacity for chronicity and refractoriness during the course of disease. The transcranial direct current stimulation (tDCS) - a safe, portable, and inexpensive neuromodulation technique - has emerged as a promising treatment for the management of auditory hallucinations.

OBJECTIVE

The aim of this study is to analyze the level of evidence in the literature available for the use of tDCS as a treatment for auditory hallucinations in schizophrenia.

METHODS

A systematic review was performed, searching in the main electronic databases including the Cochrane Library and MEDLINE/PubMed. The searches were performed by combining descriptors, applying terms of the Medical Subject Headings (MeSH) of Descriptors of Health Sciences and descriptors contractions. PRISMA protocol was used as a guide and the terms used were the clinical outcomes ("Schizophrenia" OR "Auditory Hallucinations" OR "Auditory Verbal Hallucinations" OR "Psychosis") searched together ("AND") with interventions ("transcranial Direct Current Stimulation" OR "tDCS" OR "Brain Polarization").

RESULTS

Six randomized controlled trials that evaluated the effects of tDCS on the severity of auditory hallucinations in schizophrenic patients were selected. Analysis of the clinical results of these studies pointed toward incongruence in the information with regard to the therapeutic use of tDCS with a view to reducing the severity of auditory hallucinations in schizophrenia. Only three studies revealed a therapeutic benefit, manifested by reductions in severity and frequency of auditory verbal hallucinations in schizophrenic patients.

CONCLUSION

Although tDCS has shown promising results in reducing the severity of auditory hallucinations in schizophrenic patients, this technique cannot yet be used as a therapeutic alternative due to lack of studies with large sample sizes that portray the positive effects that have been described.

Spared Primary Motor Cortex and The Presence of MEP in Cerebral Palsy Dictate the Responsiveness to tDCS during Gait Training

The current priority of investigations involving transcranial direct current stimulation (tDCS) and neurorehabilitation is to identify biomarkers associated with the positive results of the interventions such that respondent and non-respondent patients can be identified in the early phases of treatment. The aims were to determine whether: (1) present motor evoked potential (MEP); and (2) injuries involving the primary motor cortex, are associated with tDCS-enhancement in functional outcome following gait training in children with cerebral palsy (CP). We reviewed the data from our parallel, randomized, sham-controlled, double-blind studies. Fifty-six children with spastic CP received gait training (either treadmill training or virtual reality training) and tDCS (active or sham). Univariate and multivariate logistic regression analyses were employed to identify clinical, neurophysiologic and neuroanatomic predictors associated with the responsiveness to treatment with tDCS. MEP presence during the initial evaluation and the subcortical injury were associated with positive effects in the functional results. The logistic regression revealed that present MEP was a significant predictor for the six-minute walk test (6MWT; p = 0.003) and gait speed (p = 0.028), whereas the subcortical injury was a significant predictor of gait kinematics (p = 0.013) and gross motor function (p = 0.021). In this preliminary study involving children with CP, two important prediction factors of good responses to anodal tDCS combined with gait training were identified. Apparently, MEP (integrity of the corticospinal tract) and subcortical location of the brain injury exerted different influences on aspects related to gait, such as velocity and kinematics.

Behavioral effects of transcranial pulsed current stimulation (tPCS): Speed-accuracy tradeoff in attention switching task

Transcranial pulsed current stimulation (tPCS) has been shown to increase inter-hemispheric coherence of brain oscillatory activity, mainly in fronto-temporal regions, leading to enhancement of functional connectivity across neural networks. The question is whether tPCS can modulate behavior significantly. Our aim was to identify the effects of tPCS on paired associative learning task (PALT) and attention switching task (AST), and to further categorize physiological autonomic responses by heart rate variability and electrodermal activity measurements before and after task performance. Thirty healthy volunteers were randomized to receive a single session of sham or active 2mA tPCS stimulation with a random frequency between 1 and 5Hz. We show that active tPCS significantly improved response time in the AST compared to sham stimulation, so that subjects who received active tPCS significantly exhibit decreased switching cost between repeat and switch trials. No differences were found in response accuracy on AST and PALT. No significant changes were observed in physiological parameters. Based on our results, we suggest that tPCS has a more pronounced effect on tasks that require the increase of functional connectivity across pre-existent neural circuitry, rather than on tasks that require the development of new learning circuits or the creation of new connections.

A Randomized, Double-Blind, Sham-Controlled Trial of Transcranial Direct Current Stimulation in Attention-Deficit/Hyperactivity Disorder

Background

Current standardized treatments for cognitive impairment in attention-deficit/hyperactivity disorder remain limited and their efficacy restricted. Transcranial direct current stimulation (tDCS) is a promising tool for enhancing cognitive performance in several neuropsychiatric disorders. Nevertheless, the effects of tDCS in reducing cognitive impairment in patients with attention-deficit/hyperactivity disorder (ADHD) have not yet been investigated.

Methods

A parallel, randomized, double-blind, sham-controlled trial was conducted to examine the efficacy of tDCS on the modulation of inhibitory control in adults with ADHD. Thirty patients were randomly allocated to each group and performed a go/no-go task before and after a single session of either anodal stimulation (1 mA) over the left dorsolateral prefrontal cortex or sham stimulation.

Results

A nonparametric two-sample Wilcoxon rank-sum (Mann-Whitney) test revealed no significant differences between the two groups of individuals with ADHD (tDCS vs. sham) in regard to behavioral performance in the go/no go tasks. Furthermore, the effect sizes of group differences after treatment for the primary outcome measures—correct responses, impulsivity and omission errors—were small. No adverse events resulting from stimulation were reported.

Conclusion

According to these findings, there is no evidence in support of the use of anodal stimulation over the left dorsolateral prefrontal cortex as an approach for improving inhibitory control in ADHD patients. To the best of our knowledge, this is the first clinical study to assess the cognitive effects of tDCS in individuals with ADHD. Further research is needed to assess the clinical efficacy of tDCS in this population.

Trial Registration

ClinicalTrials.gov NCT01968512

Contribution of transcranial direct current stimulation on inhibitory control to assess the neurobiological aspects of attention deficit hyperactivity disorder: randomized controlled trial

Background

The applicability of transcranial direct current stimulation (tDCS) in individuals with attention deficit hyperactivity disorder (ADHD) has not yet been investigated. This low-cost, non-invasive, and safe technique optimized to modulate the inhibitory response might be a useful treatment option for those affected by this condition.

Objective

The aim of this single center, parallel, randomized, double-blinded, sham-controlled trial is to investigate the efficacy of transcranial direct current stimulation over the prefrontal cortex on the modulation of inhibitory control in adults with attention deficit hyperactivity disorder.

Methods

A total of 60 individuals will be divided into 2 groups by block randomization to receive active or sham stimulation. Anodal stimulation over the left dorsolateral prefrontal cortex will be applied at 1 mA during a single 20-minute session. Before and after interventions, subjects will perform 2 go/no go tasks and the brain electrical activity will be recorded by electroencephalogram (EEG) with 32 channels, according to the 10-20 international EEG system.

Results

The trial began in May 2013 and we are currently performing the statistical analysis for the secondary outcomes.

Conclusions

The findings from this study will provide preliminary results about the role of prefrontal cortex activation through tDCS on ADHD patients.

Trial Registration

Clinicaltrials.gov NCT01968512; http://clinicaltrials.gov/ct2/show/NCT01968512 (Archived by WebCite at www.webcitation.org/6YMSW2tkD).

Spreading Effect of tDCS in Individuals with Attention-Deficit/Hyperactivity Disorder as Shown by Functional Cortical Networks: A Randomized, Double-Blind, Sham-Controlled Trial

BACKGROUND

Transcranial direct current stimulation (tDCS) is known to modulate spontaneous neural network excitability. The cognitive improvement observed in previous trials raises the potential of this technique as a possible therapeutic tool for use in attention-deficit/hyperactivity disorder (ADHD) population. However, to explore the potential of this technique as a treatment approach, the functional parameters of brain connectivity and the extent of its effects need to be more fully investigated.

OBJECTIVE

The aim of this study was to investigate a functional cortical network (FCN) model based on electroencephalographic activity for studying the dynamic patterns of brain connectivity modulated by tDCS and the distribution of its effects in individuals with ADHD.

METHODS

Sixty ADHD patients participated in a parallel, randomized, double-blind, sham-controlled trial. Individuals underwent a single session of sham or anodal tDCS at 1 mA of current intensity over the left dorsolateral prefrontal cortex for 20 min. The acute effects of stimulation on brain connectivity were assessed using the FCN model based on electroencephalography activity.

RESULTS

Comparing the weighted node degree within groups prior to and following the intervention, a statistically significant difference was found in the electrodes located on the target and correlated areas in the active group (p < 0.05), while no statistically significant results were found in the sham group (p ≥ 0.05; paired-sample Wilcoxon signed-rank test).

CONCLUSION

Anodal tDCS increased functional brain connectivity in individuals with ADHD compared to data recorded in the baseline resting state. In addition, although some studies have suggested that the effects of tDCS are selective, the present findings show that its modulatory activity spreads. Further studies need to be performed to investigate the dynamic patterns and physiological mechanisms underlying the modulatory effects of tDCS.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01968512.

Cognitive effects and autonomic responses to transcranial pulsed current stimulation

Transcranial pulsed current stimulation (tPCS) is emerging as an option in the field of neuromodulation; however, little is known about its effects on cognition and behavior and its neurophysiological correlates as indexed by autonomic responses. Our aim was to identify the effects of tPCS on arithmetic processing and risk-taking behavior, and to further categorize physiological autonomic responses by heart rate variability (HRV) and electrodermal activity measurements before, during, and after exposure to task performance and stimulation. Thirty healthy volunteers were randomized to receive a single session of sham or active stimulation with a current intensity of 2 mA and a random frequency between 1 and 5 Hz. Our results showed that tPCS has a modest and specific effect on cognitive performance as indexed by the cognitive tasks chosen in this study. There was a modest effect of active tPCS only on performance facilitation on a complex-level mathematical task as compared to sham stimulation. On autonomic responses, we observed that HRV total power increased while LF/HF ratio decreased in the tPCS active group compared to sham. There were no group differences for adverse effects. Based on our results, we conclude that tPCS, in healthy subjects, has a modest and specific cognitive effect as shown by the facilitation of arithmetical processing on complex mathematical task. These effects are accompanied by modulation of the central autonomic network providing sympathetic-vagal balance during stressful conditions. Although behavioral results were modest, they contribute to the understanding of tPCS effects and cognitive enhancement.

The importance of methylmalonic acid dosage on the assessment of patients with neurological manifestations following bariatric surgery

Vitamin B12 or cyanocobalamin is an important substance that is included in several metabolic pathways. Its deficiency is a common event after bariatric surgery, decreasing the vitamin B12 absorption after almost all of the stomach and duodenum are eliminated from the digestion process. Neurological manifestations of cyanocobalamin deficiency are not uncommon. We report a case of a young woman who developed ataxia, weakness and peripheral neuropathy after bariatric surgery, but with normal value of vitamin B12 dosage. For the diagnosis, it was necessary to dose methylmalonic acid. We discuss the importance of methylmalonic acid dosage after bariatric surgery in patients who present suspect of cyanocobalamin deficiency with normal values of this vitamin and the role of proton pump inhibitor use and vitamin supplementation in patients with early neurological presentation.