Repetitive transcranial magnetic stimulation promotes response inhibition in patients with major depression during the stop-signal task

Structural alterations after repetitive transcranial magnetic stimulation in depression and the link to neurotransmitter profiles

BACKGROUND

Repetitive Transcranial Magnetic Stimulation (rTMS) is widely used to treat depression, showing good efficacy and tolerability. However, the neurobiological mechanisms of its antidepressant effects remain unclear. This study explores the potential impact of rTMS on brain structure in depressed patients and its link to neurotransmitter systems.

METHODS

Thirty-six MDD patients were randomized to receive 5 times per week for 3 weeks of active or sham rTMS targeting the dorsolateral prefrontal cortex (DLPFC) within a double-blind, sham-controlled trial. The Hamilton Depression Rating Scale-17 items (HAMD-17) was used to assess depressive symptoms at baseline and the end of 1 W, 2 W and 3 W after treatment. We analyzed the differences in efficacy between the two groups of patients at different time points, and the grey matter changes of the brain before and after treatment in both groups. In addition, we analyzed the spatial correlations between abnormal grey matter and the neurotransmitter receptors and transporters map.

RESULTS

Both the active and sham groups showed significant improvement in depression and anxiety symptoms following rTMS treatment, with the Active group demonstrating greater improvement. Additionally, the Active group exhibited increased grey matter volume in regions associated with the frontal-limbic network, and these changes were significantly correlated with the spatial distribution of D1 receptors.

CONCLUSION

This study suggests that rTMS targeting the left DLPFC produces antidepressant effects by enhancing structural plasticity in the frontal-limbic network, and that dopamine system modulation may underlie rTMS therapeutic effects. These findings provide insight into the neurobiological basis of rTMS for depression treatment.

Comparative efficacy of multiple non-invasive brain stimulation to treat major depressive disorder in older patients: A systematic review and network meta-analysis study based on randomized controlled trials

BACKGROUND

Major depressive disorder (MDD) is prevalent among older patients and is frequently associated with cognitive decline and a reduced quality of life. Non-invasive brain stimulation (NIBS) techniques show promise for treating MDD, but their comparative efficacy and safety older populations remain unclear. This study aimed to compare the efficacy and cognitive effects of various NIBS techniques in treating MDD in older patients.

METHODS

We searched the PubMed, EMBASE, Cochrane Library, and Web of Science core databases from inception to March 2024. Seventeen randomized controlled trials (RCTs) were included.

RESULTS

Surfaces under the cumulative ranking curve (SUCRA) values were used to rank the interventions. The SUCRA rankings for the Hamilton Depression Rating Scale (HDRS) outcomes indicated that repetitive transcranial magnetic stimulation (rTMS) (89.0 %) had the highest efficacy, followed by transcranial direct current stimulation (tDCS) (68.7 %). rTMS demonstrated significantly superior efficacy compared with bilateral electroconvulsive therapy (BL ECT) and right unilateral electroconvulsive therapy (RUL ECT). Theta burst stimulation (TBS) had the highest response rate (69.6 %), followed by rTMS (61.8 %). Based on the Mini-Mental State Examination, rTMS (86.4 %) ranked the highest, with RUL ECT showing significantly better outcomes than BL ECT.

CONCLUSION

NIBS, particularly rTMS and TBS, may offer effective treatment options for older patients with MDD. Further research with larger sample sizes and longer follow-up periods is required to validate these findings and inform clinical practice.

Does the stop-signal P3 reflect inhibitory control?

The ability to stop already-initiated actions is paramount to adaptive behavior. In psychology and neuroscience alike, action-stopping is a popular model behavior to probe inhibitory control - the underlying cognitive control process that is purportedly vital to regulating thoughts and actions. Starting with seminal work in the 1990s, the frontocentral stop-signal P3 - an event-related potential derived from scalp EEG - has been proposed as a neurophysiological index of inhibitory control during action-stopping. However, this association has been challenged repeatedly over recent years. Here, we perform a critical review of both the evidence in support of the association between this P3 index and inhibitory control, as well as its documented criticisms. We first comprehensively review literature from the past three decades that suggested a link between stop-signal P3 and inhibitory control. Second, we then replicate the key empirical patterns reported in that body of literature in a uniquely large stop-signal task EEG dataset (N = 255). Third, we then examine the criticisms raised against the view of P3 as an index of inhibitory control and evaluate the evidence supporting these arguments. Finally, we present an updated view of the process(es) reflected in the stop-signal P3. Specifically, we propose that the stop-signal P3 indexes a specific, selective inhibitory control process that critically contributes to action-stopping. This view is motivated by recent two-stage models of inhibitory control and emerging empirical data. Together, we hope to clarify the process(es) reflected in the stop-signal P3 and resolve the ongoing debates regarding its utility as an index of inhibitory control during action-stopping.

Efficacy and safety of transcranial magnetic stimulation on cognition in mild cognitive impairment, Alzheimer's disease, Alzheimer's disease-related dementias, and other cognitive disorders: a systematic review and meta-analysis

OBJECTIVE

We aim to analyze the efficacy and safety of TMS on cognition in mild cognitive impairment (MCI), Alzheimer's disease (AD), AD-related dementias, and nondementia conditions with comorbid cognitive impairment.

DESIGN

Systematic review, Meta-Analysis.

SETTING

We searched MEDLINE, Embase, Cochrane database, APA PsycINFO, Web of Science, and Scopus from January 1, 2000, to February 9, 2023.

PARTICIPANTS AND INTERVENTIONS

RCTs, open-label, and case series studies reporting cognitive outcomes following TMS intervention were included.

MEASUREMENT

Cognitive and safety outcomes were measured. Cochrane Risk of Bias for RCTs and MINORS (Methodological Index for Non-Randomized Studies) criteria were used to evaluate study quality. This study was registered with PROSPERO (CRD42022326423).

RESULTS

The systematic review included 143 studies (n = 5,800 participants) worldwide, encompassing 94 RCTs, 43 open-label prospective, 3 open-label retrospective, and 3 case series. The meta-analysis included 25 RCTs in MCI and AD. Collectively, these studies provide evidence of improved global and specific cognitive measures with TMS across diagnostic groups. Only 2 studies (among 143) reported 4 adverse events of seizures: 3 were deemed TMS unrelated and another resolved with coil repositioning. Meta-analysis showed large effect sizes on global cognition (Mini-Mental State Examination (SMD = 0.80 [0.26, 1.33], p = 0.003), Montreal Cognitive Assessment (SMD = 0.85 [0.26, 1.44], p = 0.005), Alzheimer's Disease Assessment Scale-Cognitive Subscale (SMD = -0.96 [-1.32, -0.60], p < 0.001)) in MCI and AD, although with significant heterogeneity.

CONCLUSION

The reviewed studies provide favorable evidence of improved cognition with TMS across all groups with cognitive impairment. TMS was safe and well tolerated with infrequent serious adverse events.

Efficacy of non-invasive brain stimulation and neuronavigation for major depressive disorder: a systematic review and meta-analysis

INTRODUCTION

Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are increasingly used for major depressive disorder (MDD). Most tDCS and rTMS studies target the left dorsolateral prefrontal cortex, either with or without neuronavigation. We examined the effect of rTMS and tDCS, and the added value of neuronavigation in the treatment of MDD.

METHODS

A search on PubMed, Embase, and Cochrane databases for rTMS or tDCS randomized controlled trials of MDD up to 1 February 2023, yielded 89 studies. We then performed meta-analyses comparing tDCS efficacy to non-neuronavigated rTMS, tDCS to neuronavigated rTMS, and neuronavigated rTMS to non-neuronavigated rTMS. We assessed the significance of the effect in subgroups and in the whole meta-analysis with a z-test and subgroup differences with a chi-square test.

RESULTS

We found small-to-medium effects of both tDCS and rTMS on MDD, with a slightly greater effect from rTMS. No significant difference was found between neuronavigation and non-neuronavigation.

CONCLUSION

Although both tDCS and rTMS are effective in treating MDD, many patients do not respond. Additionally, current neuronavigation methods are not significantly improving MDD treatment. It is therefore imperative to seek personalized methods for these interventions.

The Effect of Rhythmic Audio-Visual Stimulation on Inhibitory Control: An ERP Study

Inhibitory control, as an essential cognitive ability, affects the development of higher cognitive functions. Rhythmic perceptual stimulation has been used to improve cognitive abilities. It is unclear, however, whether it can be used to improve inhibitory control. This study used the Go/NoGo task and the Stroop task to assess various levels of inhibitory control using rhythmic audio-visual stimuli as the stimulus mode. Sixty subjects were randomly divided into three groups to receive 6 Hz, 10 Hz, and white noise stimulation for 30 min. Two tasks were completed by each subject both before and after the stimulus. Before and after the task, closed-eye resting EEG data were collected. The results showed no differences in behavioral and EEG measures of the Go/NoGo task among the three groups. While both 6 Hz and 10 Hz audio-visual stimulation reduced the conflict effect in the Stroop task, only 6 Hz audio-visual stimulation improved the amplitude of the N2 component and decreased the conflict score. Although rhythmic audio-visual stimulation did not enhance response inhibition, it improved conflict inhibition.

Using functional near-infrared spectroscopy to study effects of virtual reality intervention for adolescents with depression in a clinical setting in China: study protocol for a prospective, randomised, controlled trial

INTRODUCTION

Adolescent depression has been shown to be associated with many devastating psychosocial outcomes. However, there are many barriers that may prevent depressed individuals from receiving specialised treatment. Virtual reality (VR) technology has shown promise as one avenue for overcoming these challenges. This study first aims to evaluate the effectiveness of VR intervention on adolescent depression symptoms, and second, to determine the intervention's underlying mechanism of effect using functional near-infrared spectroscopy (fNIRS).

METHODS AND ANALYSIS

This is a single-centre, prospective, randomised controlled clinical trial. Sixty-six eligible adolescents aged 12-18 years with a diagnosis of depression will be randomised in a 1:1 ratio to either the VR treatment group or the conventional treatment group. All patients for both groups will receive usual treatment during a 4-week intervention period. In addition, patients randomised to VR treatment group (n=33) will complete three 20 min VR sessions including attention, executive function and relaxation training per week. Moreover, 33 healthy adolescents will be recruited as the general population. Primary outcome (ie, depressive symptoms) and secondary outcomes (ie, anxiety symptoms, executive function, treatment emergent symptoms, haemoglobin changes measured by fNIRS) will be collected at preintervention, immediately postintervention and at 4 weeks follow-up. The data assessor and analyst will be blinded to group membership.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Ethics Committee of Lishui Second People's Hospital. Written informed consent will be obtained for all participants. Results will be disseminated through peer-reviewed journals, national or international conference presentations, media outlets, the internet and various community activities.

TRIAL REGISTRATION NUMBER

ChiCTR2300067747.

The changes in metabolomics profile induced by intermittent theta burst stimulation in major depressive disorder: an exploratory study

BACKGROUND

Recently, there has been an ongoing interest in the mechanism of intermittent theta burst stimulation (iTBS) in major depressive disorder. Studying the metabolite changes induced by iTBS may help to understand the mechanism.

METHODS

Eleven participants with major depressive disorder received 10 days iTBS treatment. Magnetic resonance imaging (MRI) was used to target the region of the left dorsolateral prefrontal cortex (DLPFC) in each participant. We analyzed the effects of iTBS on metabolites using high-throughput profiling and assessed its impact on depressive symptoms. These analyses were considered exploratory, and no correction for multiple comparisons was applied.

RESULTS

Among the 318 measured metabolites, a significant increase in cystine, asymmetric dimethylarginine (ADMA), 1-methylhistidine, indoleacetic acid (IAA), diethanolamine (DEA), dopa, riboflavin-5'-monophosphate (FMN), and a significant decrease in alphalinolenic acid (ALA), gamma-linolenic acid (GLA), serotonin, linoleic acid (LA) (p < 0.05) were detected in the patients after iTBS treatment. In Pearson correlation analysis, the plasma levels of LA, FMN and ADMA at baseline were significantly related to the reduction rate of the 17-item Hamilton Depression Rating Scale and the Patient Health Questionnaire-9 scores (p < 0.05).

CONCLUSIONS

Our study highlights that LA, FMN, ADMA and their relationship with oxidative stress, may be key factors in the antidepressant efficacy of iTBS.

High-frequency rTMS over the left DLPFC improves the response inhibition control of young healthy participants: an ERP combined 1H-MRS study

Introduction

Unlike the effect of repetitive transcranial magnetic stimulation (rTMS) in treating neuropsychiatric diseases, little is known about how personal factors might account for the disparity of results from studies of cognition and rTMS. In this study, we investigated the effects of high-frequency rTMS on response inhibition control and explored the time course changes in cognitive processing and brain metabolic mechanisms after rTMS using event-related potentials (ERPs) and magnetic resonance spectroscopy (¹H-MRS).

Methods

Participants were all right-handed and were naive to rTMS and the Go/NoGo task. Twenty-five healthy young participants underwent one 10 Hz rTMS session per day in which stimulation was applied over the left dorsolateral prefrontal cortex (DLPFC), and a homogeneous participant group of 25 individuals received a sham rTMS treatment for 1  week. A Go/NoGo task was performed, an electroencephalogram (EEG) was recorded, and ¹H-MRS was performed.

Results

The results revealed that there was a strong trend of decreasing commission errors of NoGo stimuli by high frequency rTMS over the left DLPFC, whereas there was no significant difference between before and after rTMS treatment with respect to these parameters in the sham rTMS group. High-frequency rTMS significantly increased the amplitude of NoGo-N2 but not Go-N2, Go-P3, or NoGo-P3. The myo-inositol /creatine complex (MI/Cr) ratio, indexing cerebral metabolism, in the left DLPFC was decreased in the rTMS treated group.

Discussion

This observation supports the view that high-frequency rTMS over the left DLPFC has the strong tendency of reducing commission errors behaviorally, increase the amplitude of NoGo-N2 and improve the response inhibition control of healthy young participants. The results are consistent with the excitatory properties of high frequency rTMS. We suggest that the increase in the NoGo-N2 amplitude may be related to the increased excitability of the DLPFC-anterior cingulate cortex (ACC) neural loop. Metabolic changes in the DLPFC may be a possible mechanism for the improvement of the response inhibition control of rTMS.

Cognitive functioning as predictor and marker of response to repetitive transcranial magnetic stimulation in depressive disorders: A systematic review

OBJECTIVE

Cognitive performance in Major Depressive Disorder (MDD) is frequently impaired and related to functional outcomes. Repetitive Transcranial Magnetic Stimulation (rTMS) may exert its effects on MDD acting both on depressive symptoms and neurocognition. Furthermore, cognitive status could predict the therapeutic response of depressive symptoms to rTMS. However, cognitive performances as a predictor of rTMS response in MDD has not been thoroughly investigated. This review aims to evaluate the role of pre-treatment cognitive performance as a predictor of clinical response to rTMS, and the effects of rTMS on neurocognition in MDD.

METHOD

A systematic review of studies evaluating neurocognition in MDD as an outcome and/or predictor of response to rTMS was conducted using PubMed/Medline and Embase.

RESULTS

Fifty-eight articles were identified: 25 studies included neurocognition as a predictor of response to rTMS; 56 used cognitive evaluation as an outcome of rTMS. Baseline cognitive performance and cognitive improvements after rTMS predicted clinical response to rTMS. Moreover, rTMS improved cognition in MDD.

CONCLUSIONS

Cognitive assessment could predict improvement of depression in MDD patients undergoing rTMS and help selecting patients that could have beneficial effects from rTMS. A routine cognitive assessment might stratify MDD patients and track rTMS related cognitive improvement.