Antidepressant efficacy of high-frequency transcranial magnetic stimulation over the left dorsolateral prefrontal cortex in double-blind sham-controlled designs: a meta-analysis

Combination of Transcranial Magnetic Stimulation and Ketamine in Treatment-Resistant Depression: A Systematic Review

Treatment-resistant depression (TRD) is a significant challenge in psychiatric practice, affecting a substantial proportion of patients with major depressive disorder (MDD). Traditional treatment modalities often fall short, necessitating the exploration of alternative therapies. This literature review examines the combined use of Transcranial Magnetic Stimulation (TMS) and ketamine in treating TRD. The objective of this study is to evaluate the efficacy, safety, and potential synergies of combining TMS and ketamine in the treatment of TRD. A comprehensive literature search was conducted using PubMed and Google Scholar databases from 2014 to 2024. The search terms included combinations of "Transcranial Magnetic Stimulation," "Ketamine," "Depression," "Major Depressive Disorder," "Treatment-Resistant Depression," and "Combination." After screening for relevance and applying inclusion and exclusion criteria, six studies were selected for review, including three case reports, a retrospective study, a pilot study, and a review study. The selected studies demonstrated that the combination of TMS and ketamine resulted in substantial and sustained improvement in depressive symptoms for patients with TRD. Case reports and retrospective studies highlighted significant reductions in depression severity and improvements in psychosocial functioning. The combination therapy showed a higher efficacy compared to monotherapies of either TMS or ketamine alone. Notably, adverse effects were generally mild and transient, with no severe adverse events reported in most studies. In conclusion, the combination of TMS and ketamine presents a promising treatment modality for patients with TRD, offering significant improvements in depressive symptoms and better outcomes compared to traditional monotherapies. However, the heterogeneity in study designs and small sample sizes underline the need for larger, randomized controlled trials to establish standardized protocols and further validate these findings.

Real-world outcome of rTMS treatment for depression within the Japanese public health insurance system: Registry data from Kansai TMS network

This study registered consecutive cases to elucidate the efficacy of rTMS treatment for depression within the Japanese public health insurance system. Of the 102 patients with depression who received rTMS over the left dorsolateral prefrontal cortex, 44 (43.1 %) patients reached remission and 14 (13.7 %) patients did not reach remission but responded to treatment. No serious adverse events occurred. Low baseline HAMD-17 score was associated with remission after rTMS treatment. Favorable outcomes of rTMS treatment were shown in this cohort within the Japanese public insurance system. Our results provide insights into rTMS treatment for depression in real-world clinical setting.

A randomized controlled trial of intermittent theta burst stimulation to the medial prefrontal cortex for tobacco use disorder: Clinical efficacy and safety

OBJECTIVE

This study aimed to evaluate the clinical efficacy and safety of administering intermittent theta burst stimulation (iTBS) to the medial prefrontal cortex for tobacco use disorder.

METHODS

A randomized sham-controlled trial was conducted, with 38 participants receiving 28 sessions of active (n=25) or sham (n=13) iTBS (2 sessions/day, 600 pulses/session, 110% resting motor threshold, AFz target) along with smoking cessation education (Forever Free © booklets) over 14 visits. Primary outcomes included self-reported cigarette consumption and abstinence, verified by urinary cotinine tests. Secondary outcomes included symptoms of tobacco use disorder, negative mood, and safety/tolerability.

RESULTS

Both active and sham groups reported reduced cigarette consumption (β = -0.12, p = 0.015), cigarette craving (β = -0.16, p = 0.002), and tobacco withdrawal symptoms (β = -0.05, p < 0.001). However, there were no significant time x group interaction effects for any measure. Similarly, the two groups had no significant differences in urinary cotinine-verified abstinence. Adverse events occurred with similar frequency in both groups.

CONCLUSION

There were no differences in cigarette consumption between the active and sham iTBS groups, both groups decreased cigarette consumption similarly. Further research is needed to compare iTBS to standard high-frequency rTMS and explore the potential differences in efficacy. Despite limitations, this study contributes to experimental design considerations for TMS as a novel intervention for tobacco and other substance use disorders, emphasizing the need for a more comprehensive understanding of the stimulation parameters and target sites.

Functional magnetic resonance imaging in schizophrenia: current evidence, methodological advances, limitations and future directions

Functional neuroimaging emerged with great promise and has provided fundamental insights into the neurobiology of schizophrenia. However, it has faced challenges and criticisms, most notably a lack of clinical translation. This paper provides a comprehensive review and critical summary of the literature on functional neuroimaging, in particular functional magnetic resonance imaging (fMRI), in schizophrenia. We begin by reviewing research on fMRI biomarkers in schizophrenia and the clinical high risk phase through a historical lens, moving from case-control regional brain activation to global connectivity and advanced analytical approaches, and more recent machine learning algorithms to identify predictive neuroimaging features. Findings from fMRI studies of negative symptoms as well as of neurocognitive and social cognitive deficits are then reviewed. Functional neural markers of these symptoms and deficits may represent promising treatment targets in schizophrenia. Next, we summarize fMRI research related to antipsychotic medication, psychotherapy and psychosocial interventions, and neurostimulation, including treatment response and resistance, therapeutic mechanisms, and treatment targeting. We also review the utility of fMRI and data-driven approaches to dissect the heterogeneity of schizophrenia, moving beyond case-control comparisons, as well as methodological considerations and advances, including consortia and precision fMRI. Lastly, limitations and future directions of research in the field are discussed. Our comprehensive review suggests that, in order for fMRI to be clinically useful in the care of patients with schizophrenia, research should address potentially actionable clinical decisions that are routine in schizophrenia treatment, such as which antipsychotic should be prescribed or whether a given patient is likely to have persistent functional impairment. The potential clinical utility of fMRI is influenced by and must be weighed against cost and accessibility factors. Future evaluations of the utility of fMRI in prognostic and treatment response studies may consider including a health economics analysis.

A pilot, randomized clinical trial: Left dorsolateral prefrontal cortex intermittent theta burst stimulation improves treatment outcomes in veterans with alcohol use disorder

BACKGROUND

Transcranial magnetic stimulation (TMS) offers a promising treatment avenue to modulate brain function in alcohol use disorder (AUD). To the best of our knowledge, this pilot study is the first randomized, double-blind, sham-controlled trial to deliver intermittent theta burst stimulation to the left dorsolateral prefrontal cortex (DLPFC) among US veterans with AUD. We hypothesized that 20 sessions of real TMS are tolerable and feasible. As a secondary line of inquiry, we hypothesized that, relative to sham TMS, individuals receiving real TMS would experience greater reductions in 6-month relapse rates, anhedonia, and alcohol cue-reactivity.

METHODS

Veterans (n = 17, one woman) were enrolled in a double-blind, sham-controlled trial (2-3 sessions/day; 7-10 days; 600 pulses/session; 20 sessions). Pre- and posttreatment assessments included responses to self-report questionnaires and functional magnetic resonance imaging measures of alcohol cue-reactivity. Alcohol consumption was assessed for 6 months. Linear mixed-effects models were constructed to predict posttreatment craving, mood, and cue-reactivity.

RESULTS

Individuals who received active iTBS (n = 8) were less likely to relapse within 3 months after treatment than the sham-treated group (n = 9) (OR = 12.0). Greater reductions in anhedonia were observed following active iTBS (Cohen's d = -0.59), relative to sham (d = -0.25). Alcohol cue-reactivity was reduced following active iTBS and increased following sham within the left insula (d = -0.19 vs. 0.51), left thalamus (d = -0.28 vs. 0.77), right insula (d = 0.18 vs. 0.52), and right thalamus (d = -0.06 vs. 0.62).

CONCLUSIONS

Relative to sham, we demonstrate that 20 sessions of real left DLPFC iTBS reduced the likelihood of relapse for at least 3 months. The potential utility of this approach is underscored by observed decreases in anhedonia and alcohol cue-reactivity-strong predictors of relapse among veterans. These initial data offer a valuable set of effect sizes to inform future clinical trials in this patient population.

Systematic cross-species comparison of prefrontal cortex functional networks targeted via Transcranial Magnetic Stimulation

Transcranial Magnetic Stimulation (TMS) is a non-invasive brain stimulation method that safely modulates neural activity in vivo. Its precision in targeting specific brain networks makes TMS invaluable in diverse clinical applications. For example, TMS is used to treat depression by targeting prefrontal brain networks and their connection to other brain regions. However, despite its widespread use, the underlying neural mechanisms of TMS are not completely understood. Non-human primates (NHPs) offer an ideal model to study TMS mechanisms through invasive electrophysiological recordings. As such, bridging the gap between NHP experiments and human applications is imperative to ensure translational relevance. Here, we systematically compare the TMS-targeted functional networks in the prefrontal cortex in humans and NHPs. To conduct this comparison, we combine TMS electric field modeling in humans and macaques with resting-state functional magnetic resonance imaging (fMRI) data to compare the functional networks targeted via TMS across species. We identified distinct stimulation zones in macaque and human models, each exhibiting variations in the impacted networks (macaque: Frontoparietal Network, Somatomotor Network; human: Frontoparietal Network, Default Network). We identified differences in brain gyrification and functional organization across species as the underlying cause of found network differences. The TMS-network profiles we identified will allow researchers to establish consistency in network activation across species, aiding in the translational efforts to develop improved TMS functional network targeting approaches.

Effects of rTMS Intervention on Functional Neuroimaging Activities in Adolescents with Major Depressive Disorder Measured Using Resting-State fMRI

Repetitive transcranial magnetic stimulation (rTMS) to the left dorsolateral prefrontal cortex (L-DLPFC) is commonly used for the clinical treatment of major depressive disorder (MDD). The neuroimaging biomarkers and mechanisms of rTMS are still not completely understood. This study aimed to explore the functional neuroimaging changes induced by rTMS in adolescents with MDD. A total of ten sessions of rTMS were administrated to the L-DLPFC in thirteen adolescents with MDD once a day for two weeks. All of them were scanned using resting-state functional magnetic resonance imaging at baseline and after rTMS treatment. The regional homogeneity (ReHo), amplitude of low-frequency fluctuation (ALFF), and the subgenual anterior cingulate cortex (sgACC)-based functional connectivity (FC) were computed as neuroimaging indicators. The correlation between changes in the sgACC-based FC and the improvement in depressive symptoms was also analyzed. After rTMS treatment, ReHo and ALFF were significantly increased in the L-DLPFC, the left medial prefrontal cortex, bilateral medial orbital frontal cortex, and the left ACC. ReHo and ALFF decreased mainly in the left middle occipital gyrus, the right middle cingulate cortex (MCC), bilateral calcarine, the left cuneus, and the left superior occipital gyrus. Furthermore, the FCs between the left sgACC and the L-DLPFC, the right IFGoper, the left MCC, the left precuneus, bilateral post-central gyrus, the left supplementary motor area, and the left superior marginal gyrus were enhanced after rTMS treatment. Moreover, the changes in the left sgACC-left MCC FC were associated with an improvement in depressive symptoms in early improvers. This study showed that rTMS treatment in adolescents with MDD causes changes in brain activities and sgACC-based FC, which may provide basic neural biomarkers for rTMS clinical trials.

The priming effect of repetitive transcranial magnetic stimulation on clinical response to electroconvulsive therapy in treatment-resistant depression: a randomized, double-blind, sham-controlled study

BACKGROUND

Electroconvulsive therapy (ECT) is one of the most effective treatments for treatment-resistant depression (TRD). However, due to response delay and cognitive impairment, ECT remains an imperfect treatment. Compared to ECT, repetitive transcranial magnetic stimulation (rTMS) is less effective at treating severe depression, but has the advantage of being quick, easy to use, and producing almost no side effects. In this study, our objective was to assess the priming effect of rTMS sessions before ECT on clinical response in patients with TRD.

METHODS

In this multicenter, randomized, double-blind, sham-controlled trial, 56 patients with TRD were assigned to active or sham rTMS before ECT treatment. Five sessions of active/sham neuronavigated rTMS were administered over the left dorsolateral prefrontal cortex (20 Hz, 90% resting motor threshold, 20 2 s trains with 60-s intervals, 800 pulses/session) before ECT (which was active for all patients) started. Any relative improvements were then compared between both groups after five ECT sessions, in order to assess the early response to treatment.

RESULTS

After ECT, the active rTMS group exhibited a significantly greater relative improvement than the sham group [43.4% (28.6%) v. 25.4% (17.2%)]. The responder rate in the active group was at least three times higher. Cognitive complaints, which were assessed using the Cognitive Failures Questionnaire, were higher in the sham rTMS group compared to the active rTMS group, but this difference was not corroborated by cognitive tests.

CONCLUSIONS

rTMS could be used to enhance the efficacy of ECT in patients with TRD. ClinicalTrials.gov: NCT02830399.

The effect of repetitive transcranial magnetic stimulation on electroencephalography microstates of patients with heroin-addiction

The effects of transcranial magnetic stimulation in treating substance use disorders are gaining attention; however, most existing studies used subjective measures to examine the treatment effects. Objective electroencephalography (EEG)-based microstate analysis is important for measuring the efficacy of transcranial magnetic stimulation in patients with heroin addiction. We investigated dynamic brain activity changes in individuals with heroin addiction after transcranial magnetic stimulation using microstate indicators. Thirty-two patients received intermittent theta-burst stimulation (iTBS) over the left dorsolateral prefrontal cortex. Resting-state EEG data were collected pre-intervention and 10 days post-intervention. The feature values of the significantly different microstate classes were computed using a K-means clustering algorithm. Four EEG microstate classes (A-D) were noted. There were significant increases in the duration, occurrence, and contribution of microstate class A after the iTBS intervention. K-means classification accuracy reached 81.5%. The EEG microstate is an effective improvement indicator in patients with heroin addiction treated with iTBS. Microstates were examined using machine learning; this method effectively classified the pre- and post-intervention cohorts among patients with heroin addiction and healthy individuals. Using EEG microstate to measure heroin addiction and further exploring the effect of iTBS in patients with heroin addiction merit clinical investigation.

Efficacy and safety of transcranial magnetic stimulation for treating major depressive disorder: An umbrella review and re-analysis of published meta-analyses of randomised controlled trials

OBJECTIVES

We re-analysed data from published meta-analyses testing the effects of Transcranial Magnetic Stimulation (TMS) on Major Depressive Disorder (MDD) in adults. We applied up-to-date meta-analytic techniques for handling heterogeneity including the random-effects Hartung-Knapp-Sidik-Jonkman method and estimated 95% prediction intervals. Heterogeneity practices in published meta-analyses were assessed as a secondary aim.

STUDY DESIGN AND SETTING

We performed systematic searches of systematic reviews with meta-analyses that included randomised controlled trials assessing the efficacy, tolerability, and side effects of TMS on MDD. We performed risk of bias assessment using A MeaSurement Tool to Assess Reviews (AMSTAR) 2 and re-analysed meta-analyses involving 10 or more primary studies.

RESULTS

We included 29 systematic reviews and re-analysed 15 meta-analyses. Authors of all meta-analyses interpreted findings to suggest TMS is safe and effective for MDD. Our re-analysis showed that in 14 out of 15 meta-analyses, the 95% prediction intervals included the null and captured values in the opposite effect direction. We also detected presence of small-study effects in some meta-analyses and 24 out of 25 systematic reviews received an AMSTAR 2 rating classed as critically low.

CONCLUSION

Authors of all included meta-analyses interpreted findings to suggest TMS is safe and effective for MDD despite lack of comprehensive investigation of heterogeneity. Our re-analysis revealed the direction and magnitude of treatment effects vary widely across different settings. We also found high risk of bias in the majority of included systematic reviews and presence of small-study effects in some meta-analyses. Because of these reasons, we argue TMS for MDD may not be as effective and potentially less tolerated in some populations than current evidence suggests.

Electroceutical and Bioelectric Therapy: Its Advantages and Limitations

Given the long history, the field of electroceutical and bioelectric therapy has grown impressively, recognized as the main modality of mental health treatments along with psychotherapy and pharmacotherapy. Electroceutical and bioelectric therapy comprises electroconvulsive therapy (ECT), vagus nerve stimulation (VNS), repetitive transcranial magnetic stimulation (rTMS), deep brain stimulation (DBS), transcranial electrical stimulation (tES), and other brain stimulation techniques. Much empirical research has been published regarding the application guidelines, mechanism of action, and efficacy of respective brain stimulation techniques, but no comparative study that delineates the advantages and limitations of each therapy exists for a comprehensive understanding of each technique. This review provides a comparison of existing electroceutical and bioelectric techniques, primarily focusing on the therapeutic advantages and limitations of each therapy in the current electroceutical and bioelectric field.

Effects of bilateral sequential theta-burst stimulation on 5-HT1A receptors in the dorsolateral prefrontal cortex in treatment-resistant depression: a proof-of-concept trial

Theta-burst stimulation (TBS) represents a brain stimulation technique effective for treatment-resistant depression (TRD) as underlined by meta-analyses. While the methodology undergoes constant refinement, bilateral stimulation of the dorsolateral prefrontal cortex (DLPFC) appears promising to restore left DLPFC hypoactivity and right hyperactivity found in depression. The post-synaptic inhibitory serotonin-1A (5-HT1A) receptor, also occurring in the DLPFC, might be involved in this mechanism of action. To test this hypothesis, we performed PET-imaging using the tracer [carbonyl-11C]WAY-100635 including arterial blood sampling before and after a three-week treatment with TBS in 11 TRD patients compared to sham stimulation (n = 8 and n = 3, respectively). Treatment groups were randomly assigned, and TBS protocol consisted of excitatory intermittent TBS to the left and inhibitory continuous TBS to the right DLPFC. A linear mixed model including group, hemisphere, time, and Hamilton Rating Scale for Depression (HAMD) score revealed a 3-way interaction effect of group, time, and HAMD on specific distribution volume (VS) of 5-HT1A receptor. While post-hoc comparisons showed no significant changes of 5-HT1A receptor VS in either group, higher 5-HT1A receptor VS after treatment correlated with greater difference in HAMD (r = -0.62). The results of this proof-of-concept trial hint towards potential effects of TBS on the distribution of the 5-HT1A receptor. Due to the small sample size, all results must, however, be regarded with caution.

Application of Repetitive Transcranial Magnetic Stimulation in Neuropathic Pain: A Narrative Review

Neuropathic pain, affecting 6.9-10% of the general population, has a negative impact on patients' quality of life and potentially leads to functional impairment and disability. Repetitive transcranial magnetic stimulation (rTMS)-a safe, indirect and non-invasive technique-has been increasingly applied for treating neuropathic pain. The mechanism underlying rTMS is not yet well understood, and the analgesic effects of rTMS have been inconsistent with respect to different settings/parameters, causing insufficient evidence to determine its efficacy in patients with neuropathic pain. This narrative review aimed to provide an up-to-date overview of rTMS for treating neuropathic pain as well as to summarize the treatment protocols and related adverse effects from existing clinical trials. Current evidence supports the use of 10 Hz HF-rTMS of the primary motor cortex to reduce neuropathic pain, especially in patients with spinal cord injury, diabetic neuropathy and post-herpetic neuralgia. However, the lack of standardized protocols impedes the universal use of rTMS for neuropathic pain. rTMS was hypothesized to achieve analgesic effects by upregulating the pain threshold, inhibiting pain impulse, modulating the brain cortex, altering imbalanced functional connectivity, regulating neurotrophin and increasing endogenous opioid and anti-inflammatory cytokines. Further studies are warranted to explore the differences in the parameters/settings of rTMS for treating neuropathic pain due to different disease types.

Add-On Intermittent Theta Burst Stimulation Improves the Efficacy of First-Episode and Recurrent Major Depressive Disorder: Real-World Clinical Practice

OBJECTIVE

Repetitive transcranial magnetic stimulation (rTMS) is an effective and evidence-based treatment for major depressive disorder (MDD). This retrospective study aimed to explore the efficacy of add-on iTBS treatment in MDD in real-world clinical practice.

METHODS

One hundred and fifty-nine inpatients with MDD in a general hospital were included in this study. These patients were treated with at least 8 sessions of iTBS, in addition to antidepressants and supportive psychotherapy. Symptoms of depression and anxiety were assessed with the Hamilton Depression Rating Scale (HDRS) and the Hamilton Rating Scale for Anxiety (HAMA) at baseline and after 2-4 weeks of treatment. The improvement degree of depressive and anxious symptoms was compared between the first-episode MDD (n=107) and recurrent MDD (n=52) groups.

RESULTS

Depressive and anxious symptoms were reduced significantly after the add-on iTBS treatment; the response and remission rates in the first-episode MDD group were 55.14% and 28.97%, which were 63.46% and 28.85% for the recurrent MDD group, respectively (P>0.05). The response rate and remission rate of anxiety in the first-episode MDD group was 64.13% and 57.45% for HAMA, and 66.67% and 62.50% for the recurrent MDD group (P>0.05).

CONCLUSION

Our findings indicated that antidepressant and anti-anxiety efficacy of add-on iTBS treatment remains equivocal in real-world clinical practice, regardless of a first-episode depression diagnosis or recurrent depression.

Reduced subgenual cingulate-dorsolateral prefrontal connectivity as an electrophysiological marker for depression

Major Depressive Disorder (MDD) is a widespread mental illness that causes considerable suffering, and neuroimaging studies are trying to reduce this burden by developing biomarkers that can facilitate detection. Prior fMRI- and neurostimulation studies suggest that aberrant subgenual Anterior Cingulate (sgACC)-dorsolateral Prefrontal Cortex (DLPFC) functional connectivity is consistently present within MDD. Combining the need for reliable depression markers with the electroencephalogram's (EEG) high clinical utility, we investigated whether aberrant EEG sgACC-DLPFC functional connectivity could serve as a marker for depression. Source-space Amplitude Envelope Correlations (AEC) of 20 MDD patients and 20 matched controls were contrasted using non-parametric permutation tests. In addition, extracted AEC values were used to (a) correlate with characteristics of depression and (b) train a Support Vector Machine (SVM) to determine sgACC-DLPFC connectivity's discriminative power. FDR-thresholded statistical maps showed reduced sgACC-DLPFC AEC connectivity in MDD patients relative to controls. This diminished AEC connectivity is located in the beta-1 (13-17 Hz) band and is associated with patients' lifetime number of depressive episodes. Using extracted sgACC-DLPFC AEC values, the SVM achieved a classification accuracy of 84.6% (80% sensitivity and 89.5% specificity) indicating that EEG sgACC-DLPFC connectivity has promise as a biomarker for MDD.

The Association Between Sample and Treatment Characteristics and the Efficacy of Repetitive Transcranial Magnetic Stimulation in Depression: A Meta-analysis and Meta-regression of Sham-controlled Trials

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is a form of non-invasive neuromodulation that is increasingly used to treat major depressive disorder (MDD). However, treatment with rTMS could be optimized by identifying optimal treatment parameters or characteristics of patients that are most likely to benefit. This meta-analysis and meta-regression aims to identify sample and treatment characteristics that are associated with change in depressive symptom level, treatment response and remission.

METHODS

The databases PubMed, Embase, Web of Science and Cochrane library were searched for randomized controlled trials (RCTs) reporting on the therapeutic efficacy of high-frequent, low-frequent, or bilateral rTMS for MDD compared to sham. Study and sample characteristics as well as rTMS parameters and outcome variables were extracted. Effect sizes were calculated for change in depression score and risk ratios for response and remission.

RESULTS

Sixty-five RCTs with a total of 2982 subjects were included in this meta-analysis. Active rTMS resulted in a larger depressive symptom reduction than sham protocol (Hedges' g = -0.791 95% CI -0.977; -0.605). Risk ratios for response and remission were 2.378 (95% CI 1.882; 3.005) and 2.450 (95% CI 1.779; 3.375), respectively. We found no significant association between sample and treatment parameters and rTMS efficacy.

CONCLUSIONS

rTMS is an efficacious treatment for MDD. No associations between sample or treatment characteristics and efficacy were found, for which we caution that publication bias, heterogeneity and lack of consistency in the definition of remission might bias these latter null findings. Our results are clinically relevant and support the use of rTMS as a non-invasive and effective treatment option for depression.

Clinical and radiomic features for predicting the treatment response of repetitive transcranial magnetic stimulation in major neurocognitive disorder: Results from a randomized controlled trial

Image-guided repetitive transcranial magnetic stimulation (rTMS) has shown clinical effectiveness in senior adults with co-occurring depression and cognitive impairment, yet the imaging markers for predicting the treatment response are less investigated. In this clinical trial, we examined the efficacy and sustainability of 10 Hz rTMS for the treatment of depression and cognitive impairment in major neurocognitive disorder (NCD) patients and tested the predictive values of imaging-informed radiomic features in response to rTMS treatment. Fifty-five major NCD patients with depression were randomly assigned to receive a 3-week rTMS treatment of either active 10 Hz rTMS (n = 27) or sham rTMS (n = 28). Left dorsolateral prefrontal cortex (DLPFC) was the predefined treatment target. Based on individual structural magnetic resonance imaging scans, surface-based analysis was conducted to quantitatively measure the baseline radiomic features of left DLPFC. Severity of depression, global cognition and the serum brain-derived neurotrophic factor (BDNF) level were evaluated at baseline, 3-, 6- and 12-week follow-ups. Logistic regression analysis revealed that advanced age, higher baseline cognition and randomized group were associated with the remission of depression. Increased cortical thickness and gyrification in left DLPFC were the significant predictors of clinical remission and cognitive enhancement. A 3-week course of 10 Hz rTMS is an effective adjuvant treatment for rapid ameliorating depressive symptoms and enhancing cognitive function. Pre-treatment radiomic features of the stimulation target can predict the response to rTMS treatment in major NCD. Cortical thickness and folding of treatment target may serve as imaging markers to detect the responders. ChiCTR-IOR-16008191, registered on March 30, 2016.

Use of machine learning in predicting the efficacy of repetitive transcranial magnetic stimulation on treating depression based on functional and structural thalamo-prefrontal connectivity: A pilot study

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive, safe, and efficacious treatment for major depressive disorder (MDD). However, the antidepressant efficacy of rTMS greatly varies across individual patients. Thus, markers that can be used to predict the outcome of rTMS treatment at the individual level must be identified. Thalamo-cortical connectivity was abnormal in patients with MDD, and was normalized after rTMS treatment. In the current study, we investigated whether the resting-state functional and structural thalamo-cortical connectivity could be utilized to predict the rTMS treatment efficacy by employing support vector machine regression analysis. Results showed that the Hamilton Depression Scale scores of patients with MDD decreased after rTMS treatment. The functional connectivity of mediodorsal nucleus with prefrontal cortex predicted the rTMS treatment improvement, whereas the functional connectivity of other thalamic nuclei with cerebral cortex did not predict the treatment efficacy. The brain areas that contributed the most to the prediction were dorsal lateral prefrontal cortex, ventral lateral, and orbital and medial prefrontal areas. The improvement in the outcome of rTMS treatment could also be predicted by the thalamo-prefrontal structural connectivity. No statistically significantly difference in thalamo-cortical connectivity was observed between early improvers and early non-improvers. These results suggested that the thalamo-prefrontal connectivity can predict the rTMS treatment improvement. This study highlighted the crucial role of the thalamo-prefrontal connectivity as a neuroimaging marker in the treatment of depression via rTMS.

Safety of transcranial magnetic stimulation in unipolar depression: A systematic review and meta-analysis of randomized-controlled trials

BACKGROUND

To study the safety and patients' tolerance of transcranial magnetic stimulation (TMS), we conducted a systematic review and meta-analysis of the major depressive disorder population.

METHODS

Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched the literature published before April 30th, 2021 and performed a random-effects meta-analyses which included drop-out due to adverse events, serious adverse events and other non-serious adverse events as primary and secondary outcomes.

RESULTS

A total of 53 randomized sham-controlled trials with 3,273 participants were included. There was no increased risk of drop-out due to an adverse event (active TMS intervention group=3.3%, sham TMS intervention group=2.3%, odds ratio = 1.30, 95% CI= 0.78-2.16, P = 0.31) or a serious adverse event (active TMS intervention group=0.9%, sham TMS intervention group=1.5%, odds ratio = 0.67, 95% CI= 0.29-1.55, P = 0.35). Our findings suggest that TMS intervention may significantly increase the risk of non-serious adverse events including: headaches (active TMS intervention group=22.6%, sham TMS intervention group=16.2%, odds ratio = 1.48, 95% CI= 1.15-1.91, P = 0.002), discomfort (active TMS intervention group=10.9%, sham TMS intervention group=5.0%, odds ratio 1.98, 95% CI= 1.22-3.21, P = 0.006) and pain (active TMS intervention group=23.8%, sham TMS intervention group=5.2%, odds ratio= 8.09, 95% CI= 4.71-13.90, P < 0.001) at the stimulation site, but these non-serious events were mostly mild and transient after TMS treatment.

CONCLUSIONS

These findings provide evidence for the safety and patients' tolerance of transcranial magnetic stimulation technique as an alternative monotherapy or as an add-on treatment for major depressive disorder.

Decreased salience network fMRI functional connectivity following a course of rTMS for treatment-resistant depression

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is a treatment shown to be effective in treating major depressive disorder (MDD). However, the effect of rTMS therapy on functional connectivity within the brains of patients being treated for MDD remains poorly understood. Few studies have investigated the effects of a course of rTMS on resting-state network activity.

METHODS

In an open-label naturalistic study, resting-state fMRI was collected prior to and following a four-week course of rTMS in 24 participants with MDD and 2 with bipolar disorder. Montgomery-Asberg depression rating scale scores showed a response rate of 42%.

RESULTS

Clinical response to rTMS was correlated with reduced functional connectivity from baseline to post-rTMS within the salience network (SN). This indicates SN connectivity may be functionally relevant to how rTMS produces antidepressant effects. In an exploratory inter-network analysis, connectivity between the SN and posterior default mode network (pDMN) was higher following treatment. However this difference was not correlated with the antidepressant response. Local BOLD activity within these networks was also assessed using the fractional amplitude of low-frequency fluctuations (fALFF) technique. Local activity increased in both the SN and pDMN following rTMS. However this increase was also not correlated with antidepressant response.

LIMITATIONS

The sample population was heterogeneous, continuing current use of medications, and the study lacked a healthy control or sham stimulation comparison group.

CONCLUSIONS

Together, these results provide evidence for the involvement of the SN in the antidepressant response to rTMS treatment.

Neurofilament Light Chain as a Biomarker for Monitoring the Efficacy of Transcranial Magnetic Stimulation on Alcohol Use Disorder

Objective

This study assessed the effects of repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) on serum neurofilament light chain (NfL) levels, alcohol consumption, craving, and psychological impairment in participants with alcohol use disorder (AUD).

Methods

Participants with AUD were randomly assigned to receive one of two treatments (active or sham rTMS). All participants received 10 daily active or sham rTMS sessions over the left DLPFC for 2 weeks, with follow-up visits at baseline and immediately after the completion of the treatments. Serum samples were obtained before and after the intervention. Days of heavy drinking, visual analog scale (VAS) scores, and mental health component scores (MCSs) of the Medical Outcomes Study 36-Item Short Form Health Survey were used to assess the effects of rTMS.

Results

Active rTMS had a significant effect on reducing days of heavy drinking, alcohol craving, and serum NfL levels, and improved social functioning and mental health. The improvement with active rTMS was significantly greater than that with sham rTMS. Correlation analysis revealed that the reduction in the baseline drinking level was positively correlated with declines in the VAS and NfL levels but not with psychological scores.

Conclusion

Repetitive transcranial magnetic stimulation of the left DLPFC was associated with reducing alcohol consumption and craving in patients with AUD and positively impacted neuropsychological and social function. Serum NfL levels may be useful as an early serological indicator of alcohol-induced brain injury.

Increased Prefrontal Activation During Verbal Fluency Task After Repetitive Transcranial Magnetic Stimulation Treatment in Depression: A Functional Near-Infrared Spectroscopy Study

BACKGROUND

Previous studies have shown the clinical effect of 2 Hz repetitive transcranial magnetic stimulation (rTMS) for depression; however, its underlying neural mechanisms are poorly understood. The aim of this study was to examine the effects of rTMS on the activity of the prefrontal cortex in patients with depression, using functional near-infrared spectroscopy (fNIRS).

METHODS

Forty patients with major depressive disorder (MDD) and 40 healthy controls were enrolled in this study. Patients underwent 4 weeks of 2 Hz TMS delivered to the right dorsolateral prefrontal cortex (DLPFC). fNIRS was used to measure the changes in the concentration of oxygenated hemoglobin ([oxy-Hb]) in the prefrontal cortex during a verbal fluency task (VFT) in depressed patients before and after rTMS treatment. The severity of depression was assessed using the Hamilton Rating Scale for Depression-24 item (HAMD-24).

RESULTS

Prior to rTMS, depressed patients exhibited significantly smaller [oxy-Hb] values in the bilateral prefrontal cortex during the VFT compared with the healthy controls. After 4 weeks of 2 Hz right DLPFC rTMS treatment, increased [oxy-Hb] values in the bilateral frontopolar prefrontal cortex (FPPFC), ventrolateral prefrontal cortex (VLPFC) and left DLPFC during the VFT were observed in depressed patients. The increased [oxy-Hb] values from baseline to post-treatment in the right VLPFC in depressed patients were positively related to the reduction of HAMD score following rTMS.

CONCLUSION

These findings suggest that the function of the prefrontal cortex in depressed patients was impaired and could be recovered by 2 Hz rTMS. The fNIRS-measured prefrontal activation during a cognitive task is a potential biomarker for monitoring depressed patients' treatment response to rTMS.

Repetitive Transcranial Magnetic Stimulation Target Location Methods for Depression

Major depressive disorder (MDD) is a substantial global public health problem in need of novel and effective treatment strategies. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive and promising treatment for depression that has been approved by the U.S. Food and Drug Administration (FDA). However, the methodological weaknesses of existing work impairs the universal clinical use of rTMS. The variation of stimulated targets across the dorsolateral prefrontal cortex may account for most of the heterogeneity in the efficacy of rTMS. Many rTMS target location methods for MDD have been developed in recent decades. This review was conducted to assess this emerging field and to improve treatment outcomes in clinical practice.

Task-Modulated Brain Activity Predicts Antidepressant Responses of Prefrontal Repetitive Transcranial Magnetic Stimulation: A Randomized Sham-Control Study

Background

Prolonged intermittent theta-burst stimulation (piTBS) and repetitive transcranial magnetic stimulation (rTMS) are effective antidepressant interventions for major depressive disorder (MDD). Cognition-modulated frontal theta (frontalθ) activity had been identified to predict the antidepressant response to 10-Hz left prefrontal rTMS. However, whether this marker also predicts that of piTBS needs further investigation.

Methods

The present double-blind randomized trial recruited 105 patients with MDD who showed no response to at least one adequate antidepressant treatment in the current episode. The recruited patients were randomly assigned to one of three groups: group A received piTBS monotherapy; group B received rTMS monotherapy; and group C received sham stimulation. Before a 2-week acute treatment period, electroencephalopgraphy (EEG) and cognition-modulated frontal theta changes (Δfrontalθ) were measured. Depression scores were evaluated at baseline, 1 week, and 2 weeks after the initiation of treatment.

Results

The Δfrontalθ at baseline was significantly correlated with depression score changes at week 1 (r = -0.383, p = 0.025) and at week 2 for rTMS group (r = -0.419, p = 0.014), but not for the piTBS and sham groups. The area under the receiver operating characteristic curve for Δfrontalθ was 0.800 for the rTMS group (p = 0.003) and was 0.549 for the piTBS group (p = 0.619).

Conclusion

The predictive value of higher baseline Δfrontalθ for antidepressant efficacy for rTMS not only replicates previous results but also implies that the antidepressant responses to rTMS could be predicted reliably at baseline and both piTBS and rTMS could be effective through different neurobiological mechanisms.

A happiness magnet? Reviewing the evidence for repetitive transcranial magnetic stimulation in major depressive disorder

OBJECTIVES

First, to conduct a historical review of the evidence for repetitive transcranial magnetic stimulation (rTMS) for major depressive disorder and determine a clinical algorithm. Second, to identify opportunities for research.

METHODS

Literature searches were conducted of the MEDLINE database, UpToDate and the Australian National University Library SuperSearch from 1 January 2000 to 30 September 2019. The search terms used were 'transcranial magnetic stimulation', 'major depressive disorder' and 'depression'.

RESULTS

There were 24 meta-analyses identified, demonstrating a clear clinical effect. Left high-frequency rTMS had the most evidence. Ideal clinical parameters and study design were explored.

CONCLUSION

Use of rTMS for some patients with depression is justified. Open research questions include the comparative efficacy of right low-frequency and bilateral stimulation, the role of rTMS in medication-naïve patients, and maintenance of effect.

Efficacy, efficiency and safety of high-frequency repetitive transcranial magnetic stimulation applied more than once a day in depression: A systematic review

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for depression but a standard course can be time-consuming. Of all rTMS protocols, high-frequency rTMS (HF rTMS) is the most studied and applied in clinical settings. Little is known about applying multiple sessions of HF rTMS per day, in so-called accelerated schedules.

METHODS

We systematically searched electronic records up to September 2019 for studies that applied HF rTMS in accelerated schedules to treat depression to review its efficacy, efficiency and safety. Treatment effect sizes of accelerated rTMS versus standard and sham rTMS were calculated from comparison studies and pooled to derive overall treatment effect.

RESULTS

Of 1,361 records screened, 12 met review criteria. Qualitative synthesis suggested accelerated HF rTMS was equally effective as once-daily scheduling in treating depression. It is equivocal if accelerated HF rTMS results in more rapid antidepressant response. Accelerated HF rTMS was well-tolerated. The small number of studies suitable for quantitative analysis led to pooled effect sizes that did not reach statistical significance.

LIMITATIONS

There was an overall paucity of studies examining the accelerated application of HF rTMS and even fewer studies comparing accelerated HF rTMS with once-daily or sham rTMS.

CONCLUSION

Our review found comparable antidepressant efficacy between accelerated and once-daily HF rTMS. Between group differences in therapeutic effect sizes were not clinically meaningful. More studies investigating accelerated rTMS protocols are needed to validate its utility and guide clinical decision making.

Prefrontal cortex circuits in depression and anxiety: contribution of discrete neuronal populations and target regions

Our understanding of depression and its treatment has advanced with the advent of ketamine as a rapid-acting antidepressant and the development and refinement of tools capable of selectively altering the activity of populations of neuronal subtypes. This work has resulted in a paradigm shift away from dysregulation of single neurotransmitter systems in depression towards circuit level abnormalities impacting function across multiple brain regions and neurotransmitter systems. Studies on the features of circuit level abnormalities demonstrate structural changes within the prefrontal cortex (PFC) and functional changes in its communication with distal brain structures. Treatments that impact the activity of brain regions, such as transcranial magnetic stimulation or rapid-acting antidepressants like ketamine, appear to reverse depression associated circuit abnormalities though the mechanisms underlying the reversal, as well as development of these abnormalities remains unclear. Recently developed optogenetic and chemogenetic tools that allow high-fidelity control of neuronal activity in preclinical models have begun to elucidate the contributions of the PFC and its circuitry to depression- and anxiety-like behavior. These tools offer unprecedented access to specific circuits and neuronal subpopulations that promise to offer a refined view of the circuit mechanisms surrounding depression and potential mechanistic targets for development and reversal of depression associated circuit abnormalities.

A randomized controlled trial of a standard 4-week protocol of repetitive transcranial magnetic stimulation in severe treatment resistant depression

BACKGROUND

Treatment options for major depressive disorder (MDD) in individuals who are depressed for at least 2 years and failed two or more different types of therapeutic intervention, remain scarce. Being less invasive than electroconvulsive therapy, repetitive transcranial magnetic stimulation (rTMS) might be an alternative treatment option.

RESEARCH QUESTION

Does high frequency rTMS applied over the left prefrontal cortex ameliorate depressive symptoms in patients with treatment resistant major depressive disorder and is the efficacy dependent on treatment resistance?

METHOD

We performed a randomized controlled trial investigating the effect of twenty sessions of real or sham-rTMS, during 4 consecutive weeks. Efficacy was blindly rated with the Hamilton depression rating scale (HDRS-17) at baseline and 1 week after end of treatment, and the Dutch method for quantification of treatment resistance in Depression (DM-TRD) was assessed at baseline.

RESULTS

An interim analysis showed no differences in antidepressant response between real and sham rTMS and we therefore discontinued the RCT after 31 patients. The mean difference of the HDRS score between baseline and post-treatment was 3.7 (± 4.0; change 16%), indicating a small but significant improvement across time (F(1,30)=25.4;p < 0.01). There were no differences however between the treatment arms (F(1.30) = 1.5;p = 0.23). We did find a negative correlation between the change in HDRS score and DM-TRD in the active rTMS group, but this correlation was not significantly different from the sham group.

CONCLUSION

"Standard" 4-week rTMS treatment is not effective in chronic, severe treatment-resistant depressed patients. While a replication of our data in this patient group may be ethically difficult, further research with less treatment resistant patients might help in positioning rTMS within the current stepped care approach to depression.

Personalizing neuromodulation

In the era of "big data", we are gaining rich person-specific information about neuroanatomy, neural function, and cognitive functions. However, the optimal ways to create precise approaches to optimize individuals' mental functions in health and disease are unclear. Multimodal analysis and modeling approaches can guide neuromodulation by combining anatomical networks, functional signal analysis, and cognitive neuroscience paradigms in single subjects. Our progress could be improved by progressing from statistical fits to mechanistic models. Using transcranial magnetic stimulation as an example, we discuss how integrating methods with a focus on mechanisms could improve our predictions TMS effects within individuals, refine our models of health and disease, and improve our treatments.

Effects of HF-rTMS over the left and right DLPFC on proactive and reactive cognitive control

Previous research supports the distinction between proactive and reactive control. Although the dorsolateral prefrontal cortex (DLPFC) has been consistently related to these processes, lateralization of proactive and reactive control is still under debate. We manipulated brain activity to investigate the role of the left and right DLPFC in proactive and reactive cognitive control. Using a single-blind, sham-controlled crossover within-subjects design, 25 young healthy females performed the 'AX' Continuous Performance Task after receiving sham versus active High-Frequency repetitive Transcranial Magnetic Stimulation (HF-rTMS) to increase left and right DLPFC activity. RTs and pupillometry were used to assess patterns of proactive and reactive cognitive control and task-related resource allocation respectively. We observed that, compared to sham, HF-rTMS over the left DLPFC increased proactive control. After right DLPFC HF-rTMS, participants showed slower RTs on AX trials, suggesting more reactive control. However, this latter result was not supported by RTs on BX trials (i.e. the trial that specifically assess reactive control). Pupil measures showed a sustained increase in resource allocation after both active left and right HF-rTMS. Our results with RT data provide evidence on the role of the left DLPFC in proactive control and suggest that the right DLPFC is implicated in reactive control.

Two-week rTMS-induced neuroimaging changes measured with fMRI in depression

OBJECTIVE

To study the neuroimaging mechanisms of repetitive transcranial magnetic stimulation (rTMS) in treating major depressive disorder (MDD).

METHODS

Twenty-seven treatment-naive patients with major depressive disorder (MDD) and 27 controls were enrolled. All of them were scanned with resting-state functional magnetic resonance imaging (fMRI) at baseline, and 15 patients were rescanned after two-week rTMS. The amplitude of low frequency fluctuation (ALFF) and functional connection degree (FCD), based on voxels and 3 brain networks (default mode network [DMN], central executive network [CEN], salience network[SN]),were used as imaging indicators to analyze. The correlations of brain imaging changes after rTMS with clinical efficacy were calculated.

RESULTS

At baseline, patients groups showed increased ALFF in the right orbital frontal cortex (OFC) and decreased ALFF in the left striatal cortex and medial prefrontal cortex (PFC), while increased FCD in the right dorsal anterior cingulate cortex and OFC and decreased FCD in the right inferior parietal lobe and in the CEN. After rTMS, patients showed increased ALFF in the left dorsolateral prefrontal cortex (DLPFC)and superior frontal gyrus, FCD in the right dorsal anterior cingulate cortex, superior temporal gyrus and CEN, as well as decreased FCD in the bilateral lingual gyrus than pre-rTMS . These rTMS induced neuroimaging changes did not significantly correlated with clinical effecacy.

CONCLUSIONS

This study indicated that rTMS resulted in changes of ALFF and FCD in some brain regions and CEN. But we could not conclude this is the neuroimaging mechanism of rTMS according to the correlation analysis.

Interactions between transcranial direct current stimulation (tDCS) and pharmacological interventions in the Major Depressive Episode: Findings from a naturalistic study

Background:

Transcranial direct current stimulation (tDCS) is a non-invasive, neuromodulatory technique with an emerging role for treating major depression.

Objective:

To investigate the interactions between tDCS and drug therapy in unipolar and bipolar depressed patients who were refractory for at least one pharmacological treatment.

Methods:

This was a naturalistic study using data from 54 female and 28 male patients (mean age of 54 years) that consecutively visited our psychiatric unit. They received active tDCS (five consecutive days, 2 mA, anodal stimulation over the left and cathodal over the right dorsolateral prefrontal cortex, twice a day, 20 minutes). The outcome variable (mood) was evaluated using the Beck Depression Inventory (BDI) and the Hamilton Depression Rating Scale (HDRS). Predictor variables were age, gender, disorder and pharmacological treatment (seven dummy variables). We performed univariate and multivariate analyses as to identify predictors associated to the outcome.

Results:

After 5 days of treatment, BDI and HDRS scores decreased significantly (29% ± 36%, 18% ± 9%, respectively, P < 0.01 for both). Benzodiazepine use was independently associated with a worse outcome in both univariate (β = 4.92, P < 0.01) and multivariate (β = 5.8, P < 0.01) analyses; whereas use of dual-reuptake inhibitors positively changed tDCS effects in the multivariate model (β = –4.7, P = 0.02). A similar trend was observed for tricyclics (β = –4, P = 0.06) but not for antipsychotics, non-benzodiazepine anticonvulsants and other drugs.

Conclusion:

tDCS over the DLPFC acutely improved depressive symptoms. Besides the inherent limitations of our naturalistic design, our results suggest that tDCS effects might vary according to prior pharmacological treatment, notably benzodiazepines and some antidepressant classes. This issue should be further explored in controlled studies.

Effect of Low-Frequency Repetitive Transcranial Magnetic Stimulation on Impulse Inhibition in Abstinent Patients With Methamphetamine Addiction: A Randomized Clinical Trial

IMPORTANCE

Impulsivity during periods of abstinence is a critical symptom of patients who use methamphetamine (MA).

OBJECTIVE

To evaluate changes in impulse inhibition elicited by repetitive transcranial magnetic stimulation (rTMS) in patients with MA addiction.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was conducted in Da Lian Shan Addiction Rehabilitation Center, Nanjing, China, from December 1, 2018, to April 20, 2019. Effects of the intervention were examined at 3 time points: after a single session (day 1), 24 hours after 10 repeated sessions (day 11), and at 3 weeks of follow-up (day 31). Men with MA addiction and healthy male control participants were recruited for this study. Data analysis was performed from March 2019 to October 2019.

INTERVENTIONS

Patients who use MA were randomized to undergo sham rTMS (36 patients) and or 1-Hz rTMS (37 patients) to the left prefrontal cortex, receiving daily TMS treatments for 10 consecutive days.

MAIN OUTCOMES AND MEASURES

The primary outcome was impulse inhibition, which is primarily embodied by accuracy reduction (ie, accuracy cost) from standard to deviant trials in a 2-choice oddball task (80% standard and 20% deviant trials).

RESULT

The study included 73 men with MA addiction (mean [SD] age, 38.49 [7.69] years) and 33 male healthy control participants without MA addiction (mean [SD] age, 35.15 [9.68] years). The mean (SD) duration of abstinence for the men with MA addiction was 9.27 (4.61) months. Compared with the control group, patients with MA addiction exhibited greater impulsivity (accuracy cost, 3.3% vs 6.2%). The single session of 1-Hz rTMS over the left prefrontal cortex significantly increased accuracy from 91.4% to 95.7% (F1,36 = 9.58; P < .001) and reaction time delay from 50 milliseconds to 77 milliseconds (F1,36 = 22.66; P < .001) in deviant trials. These effects were seen consistently after 10 sessions of 1-Hz rTMS treatment (day 11 vs day 1, t26 = 1.59; P = .12), and the behavioral improvement was maintained at least for 3 weeks after treatment (day 31 vs day 1, t26 = 0.26; P = .80). These improvement effects of impulse inhibition were coupled with a reduction in addictive symptoms as measured by cue-induced craving. The pretest accuracy cost was positively correlated with the change in impulse inhibition (r = 0.615; P < .001) and change in craving (r = 0.334; P = .01), suggesting that these 2 behaviors may be modified simultaneously.

CONCLUSIONS AND RELEVANCE

These findings suggest that repeated rTMS sessions have sustained effects on impulse inhibition in patients with MA addiction and provide novel data on impulsivity management strategies for addiction rehabilitation.

TRIAL REGISTRATION

ChiCTR-ROC-16008541.

Antidepressant Efficacy of Prolonged Intermittent Theta Burst Stimulation Monotherapy for Recurrent Depression and Comparison of Methods for Coil Positioning: A Randomized, Double-Blind, Sham-Controlled Study

BACKGROUND

Prolonged intermittent theta burst stimulation (piTBS) with triple doses of the standard protocol is an updated form of repetitive transcranial magnetic stimulation, and it is an effective add-on intervention for major depressive disorder. In the present study, our objective was to investigate the antidepressant efficacy of piTBS monotherapy. Efficacy between the standard 5-cm method and magnetic resonance imaging (MRI)-guided coil positioning to the left dorsolateral prefrontal cortex method was also compared.

METHODS

In the present double-blind, randomized, sham-controlled trial, 105 patients with recurrent depression who exhibited no responses to at least one adequate antidepressant treatment for the prevailing episode were assigned randomly to one of three groups: piTBS monotherapy (n = 35), repetitive transcranial magnetic stimulation monotherapy (n = 35), or sham stimulation (n = 35). The acute treatment period was 2 weeks. Half of the patients were randomized to MRI navigation in each group.

RESULTS

No serious adverse events were observed. The piTBS group exhibited significantly greater decreases in depression scores than the sham group at week 2 (-40.0% vs. -13.9%; p < .001 after correcting for multiple comparisons by Bonferroni [effect size (Cohen's d) = 1.12]), and the odds ratio for responses was high. The MRI navigation method (-32.4%) did not yield better antidepressant effects than the standard method (-40.6%). Brain stimulation and 17-item Hamilton Depression Rating Scale changes in the first week were the most important variables for predicting antidepressant responses.

CONCLUSIONS

Left prefrontal piTBS monotherapy is effective for the treatment of recurrent depression, and the MRI-guided method of coil targeting is not better than the standard method.

Trends of Repetitive Transcranial Magnetic Stimulation From 2009 to 2018: A Bibliometric Analysis

Repetitive transcranial magnetic stimulation (rTMS) technology, which is amongst the most used non-invasive brain stimulation techniques currently available, has developed rapidly from 2009 to 2018. However, reports on the trends of rTMS using bibliometric analysis are rare. The goal of the present bibliometric analysis is to analyze and visualize the trends of rTMS, including general (publication patterns) and emerging trends (research frontiers), over the last 10 years by using the visual analytic tool CiteSpace V. Publications related to rTMS from 2009 to 2018 were retrieved from the Web of Science (WoS) database, including 2,986 peer-reviewed articles/reviews. Active authors, journals, institutions, and countries were identified by WoS and visualized by CiteSpace V, which could also detect burst changes to identify emerging trends. GraphPad Prism 8 was used to analyze the time trend of annual publication outputs. The USA ranked first in this field. Pascual-Leone A (author A), Fitzgerald PB (author B), George MS (author C), Lefaucheur JP (author D), and Fregni F (author E) made great contributions to this field of study. The most prolific institution to publish rTMS-related publications in the last decade was the University of Toronto. The journal Brain Stimulation published most papers. Lefaucheur et al.'s paper in 2014, and the keyword "sham controlled trial" showed the strongest citation bursts by the end of 2018, which indicates increased attention to the underlying work, thereby indicating the research frontiers. This study reveals the publication patterns and emerging trends of rTMS based on the records published from 2009 to 2018. The insights obtained have reference values for the future research and application of rTMS.

Asymmetrical Brain Plasticity: Physiology and Pathology

The brain is inherently asymmetrical. How that attribute, manifest both structurally (volumetric, cytological, molecular) as well as functionally, relates to cognitive function, is not fully understood. Since the early descriptions of Paul Broca and Marc Dax it has been known that the processing of language in the brain is fundamentally asymmetrical. Contemporary imaging studies have corroborated early observations, and have also revealed significant functional links to multiple other systems, such as those sub serving memory or emotion. Recent studies have demonstrated that laterality is both plastic and adaptive. Learning and training have shown to affect regional changes in asymmetry, such as that observed in the volume of the planum temporale associated with musical practice. Increasing task complexity has been demonstrated to induce recruitment of contralateral regions, suggesting that laterality is a manifestation of functional reserve. Indeed, in terms of cognitive function, successful aging is often associated with a reduction of asymmetrical activity. The goal of this review is to survey and critically appraise the current literature addressing brain laterality, both morphological and functional, with particular emphasis on the asymmetrical plasticity associated with environmental factors and training. The plastic recruitment of contralateral areas associated with aging and unilateral lesions will be discussed in the context of the loss of asymmetry as a compensatory mechanism, and specific instances of maladaptive plasticity will be explored.

Can psychological features predict antidepressant response to rTMS? A Discovery-Replication approach

BACKGROUND

Few studies focused on the relationship between psychological measures, major depressive disorder (MDD) and repetitive transcranial magnetic stimulation (rTMS) response. This study investigated several psychological measures as potential predictors for rTMS treatment response. Additionally, this study employed two approaches to evaluate the robustness of our findings by implementing immediate replication and full-sample exploration with strict p-thresholding.

METHODS

This study is an open-label, multi-site study with a total of 196 MDD patients. The sample was subdivided in a Discovery (60% of total sample, n = 119) and Replication sample (40% of total sample, n = 77). Patients were treated with right low frequency (1 Hz) or left high frequency (10 Hz) rTMS at the dorsolateral prefrontal cortex. Clinical variables [Beck Depression Inventory (BDI), Neuroticism, Extraversion, Openness Five-Factor Inventory, and Depression, Anxiety, and Stress Scale, and BDI subscales] were obtained at baseline, post-treatment, and at follow-up. Predictors were analyzed in terms of statistical association, robustness (independent replication), as well as for their clinical relevance [positive predictive value (PPV) and negative predictive value (NPV)].

RESULTS

Univariate analyses revealed that non-responders had higher baseline anhedonia scores. Anhedonia scores at baseline correlated negatively with total BDI percentage change over time. This finding was replicated. However, anhedonia scores showed to be marginally predictive of rTMS response, and neither PPV nor NPV reached the levels of clinical relevance.

CONCLUSIONS

This study suggests that non-responders to rTMS treatment have higher baseline anhedonia scores. However, anhedonia was only marginally predictive of rTMS response. Since all other psychological measures did not show predictive value, it is concluded that psychological measures cannot be used as clinically relevant predictors to rTMS response in MDD.

The influence of personality on the effect of iTBS after being stressed on cortisol secretion

Over the last years, individualization of repetitive Transcranial Magnetic Stimulation (rTMS) parameters has been a focus of attention in the field of non-invasive stimulation. It has been proposed that in stress-related disorders personality characteristics may influence the clinical outcome of rTMS. However, the underlying physiological mechanisms as to how personality may affect the rTMS response to stress remains to be clarified. In this sham-controlled crossover study, after being stressed by the Trier Social Stress Test, 38 healthy females received two sessions of intermittent theta burst stimulation (iTBS) applied to the left dorsolateral prefrontal cortex. To take possible personality influences into account, they also completed the Temperament and Character Inventory. Mood and salivary cortisol were assessed throughout the experimental protocol. Overall, two iTBS sessions did not significantly alter mood or influenced cortisol secretion. When taking into account personality features, higher scores on the character dimension Cooperativeness was related to decreased cortisol output, only when active iTBS was administered after the social stressor. In line with other studies, personality features such as the character dimension Cooperativeness may be of particular interest to explain individual neurobiological responses to neurostimulation.

Potential predictors of depressive relapse following repetitive Transcranial Magnetic Stimulation: A systematic review

BACKGROUND

Repetitive Transcranial Magnetic Stimulation (rTMS) is widely approved treatment for major depressive disorder (MDD). However, around 50% of individuals who recover from depression following rTMS interventions experience a relapse of depressive symptomatology by 12 months. The short-term durability of the rTMS treatment effect has been systematically investigated. However, variables relating to the long-term durability of the antidepressant effect produced by rTMS are less understood. Therefore, the current review systematically assessed the research on variables relating to relapse following rTMS.

METHOD

This systematic review was performed according to PRISMA guidelines. A comprehensive electronic literature search for terms related to relapse following rTMS treatment for MDD was performed on studies published before the end of October 2018.

RESULTS

A total of 18 studies assessing relapse related variables were identified. While there is some indication that comorbid anxiety, acute response, and residual symptomatology may hold predictive potential for depressive relapse following rTMS treatment, findings were not sufficient to draw reliable conclusions.

DISCUSSION

Identified studies assessed three main categories of variables including demographic information, clinical characteristics and rating scale scores, and rTMS treatment specific factors. Only a small number of studies were available, and considerable inconsistency exists between studies, only limited conclusions were able to be drawn.

CONCLUSION

More studies assessing a wider range of predictor variables such as cognitive or neuroimaging markers are needed.

Is rTMS effective for anxiety symptoms in major depressive disorder? An efficacy analysis comparing left-sided high-frequency, right-sided low-frequency, and sequential bilateral rTMS protocols

BACKGROUND

Anxiety symptoms are common in major depressive disorder. Whilst therapeutic efficacy of repetitive transcranial magnetic stimulation (rTMS) in depression is well-established, minimal research has investigated rTMS's efficacy in treating anxiety symptoms in depression.

METHODS

This study investigates the effectiveness of rTMS in treating anxiety symptoms in depression, specifically the relative efficacy of the three rTMS protocols commonly used in clinical practice: left-sided high-frequency, right-sided low-frequency and sequential bilateral rTMS. Antidepressant efficacy of each rTMS protocol is also investigated. Treatment data for 697 patients were pooled from three studies across five sites. Changes in Beck's Anxiety Inventory (BAI) and the Hamilton Depression Rating Scale over 4-week rTMS courses were analysed using latent growth curve modelling.

RESULTS

All rTMS protocols were effective in treating anxiety symptoms (mean BAI reduction, 8.13 points; p < 0.001) and depressive symptoms. Near therapeutic equivalence was seen across the three protocols. Improvement in depressive severity positively correlated with improvement in anxiety. Both high- and low-baseline anxiety scores showed overall symptom reduction.

CONCLUSIONS

This study addresses the clinical knowledge gap pertaining to rTMS's therapeutic efficacy in treating anxiety symptoms in depression and the relative efficacy of three commonly used stimulation protocols. Our findings suggest therapeutic equivalence across left-sided high-frequency, right-sided low-frequency, and sequential bilateral rTMS approaches.

Is theta burst stimulation ready as a clinical treatment for depression?

Introduction: Major depression is a common and debilitating mental disorder that can be difficult to treat. Substantive evidence over the past two decades has established repetitive transcranial magnetic stimulation (rTMS) as an effective antidepressant therapy, although scope exists to improve its efficacy and efficiency. Theta burst stimulation (TBS) is a novel rTMS pattern attracting much research interest as a tool to study neurophysiology and treat neuropsychiatric disorders. Areas covered: This article outlines rTMS' state of development and explores the physiology studies underpinning TBS development and its observable neuronal conditioning and metabolic effects. We present a systematic review of studies that applied TBS to treat depression, followed by commentary on safety and practical considerations. Expert opinion: Much experimental and clinical research have advanced our understanding of the antidepressant effects of TBS, although unanswered questions remain relating to its physiological effects, response variability and optimal parameters for therapeutic purposes. A small number of sham-controlled trials, and one large comparative trial, support the therapeutic efficacy of TBS and demonstrates its non-inferiority relative to traditional rTMS. In this light, TBS can reasonably be offered as an alternative to rTMS in treatment-resistant depression, while ongoing research is likely to inform its therapeutic potential.

The effect of psychotropic drugs on cortical excitability and plasticity measured with transcranial magnetic stimulation: Implications for psychiatric treatment

OBJECTIVE

Repetitive transcranial magnetic stimulation (rTMS) is an emerging treatment for neuropsychiatric disorders. Patients in rTMS treatment typically receive concomitant psychotropic medications, which affect neuronal excitability and plasticity and may interact to affect rTMS treatment outcomes. A greater understanding of these drug effects may have considerable implications for optimizing multi-modal treatment of psychiatric patients, and elucidating the mechanism(s) of action (MOA) of rTMS.

METHOD

We summarized the empirical literature that tests how psychotropic drugs affect cortical excitability and plasticity, using varied experimental TMS paradigms.

RESULTS

Glutamate antagonists robustly attenuate plasticity, largely without changes in excitability per se; antiepileptic drugs show the opposite pattern of effects, while calcium channel blockers attenuate plasticity. Benzodiazepines have moderate and variable effects on plasticity, and negligible effects on excitability. Antidepressants with potent 5HT transporter inhibition reduce both excitability and alter plasticity, while antidepressants with other MOAs generally lack either effect. Catecholaminergic drugs, cholinergic agents and lithium have minimal effects on excitability but exhibit robust and complex, non-linear effects in TMS plasticity paradigms.

LIMITATIONS

These effects remain largely untested in sustained treatment protocols, nor in clinical populations. In addition, how these medications impact clinical response to rTMS remains largely unknown.

CONCLUSIONS

Psychotropic medications exert robust and varied effects on cortical excitability and plasticity. We encourage the field to more directly and fully investigate clinical pharmaco-TMS studies to improve outcomes.

Effects of Left Versus Right Dorsolateral Prefrontal Cortex Repetitive Transcranial Magnetic Stimulation on Affective Flexibility in Healthy Women: A Pilot Study

OBJECTIVE

To determine the antidepressant mechanism of action for repetitive transcranial magnetic stimulation (rTMS) to the left dorsolateral prefrontal cortex (DLPFC) in healthy women. Our primary hypothesis was that a single session of left DLPFC rTMS, compared with a session of right DLPFC rTMS, would result in better (reduced) negative nonaffective switch costs in healthy women.

BACKGROUND

The antidepressant mechanism of action for rTMS is not clear. It is possible that rTMS to the DLPFC improves emotion regulation, which could be a part of its antidepressant mechanism.

METHODS

Twenty-five healthy women were randomized to receive left high-frequency (HF) rTMS versus right HF rTMS in one session and then contralateral stimulation during a second session. Emotion regulation was assessed via switch costs for reappraisal of negatively valenced information on an affective flexibility task.

RESULTS

For negative nonaffective switch costs, the interaction effect in the two-way ANOVA was not significant (F1,19=3.053, P=0.097). Given that left HF rTMS is the approved treatment for depression, post hoc t tests were completed with particular interest in the left-side findings. These tests confirmed that negative nonaffective switch costs significantly improved immediately after left rTMS (t1,19=2.664, P=0.015) but not right rTMS.

CONCLUSIONS

These findings suggest that left DLPFC HF rTMS may lead to antidepressant effects by improving the regulation of emotion.

Pre-scan cortisol is differentially associated with enhanced connectivity to the cognitive control network in young adults with a history of depression

BACKGROUND

We have previously demonstrated that pre-scan salivary cortisol is associated with attentuated frontal-subcortical brain activation during emotion processesing and semantic list-learning paradigms in depressed subjects. Additionally, altered functional connectivity is observed after remission of acute depression symptoms (rMDD). It is unknown whether cortisol also predicts altered functional connectivity during remission.

METHODS

Participants were 47 healthy controls (HC) and 73 rMDD, 18-30 years old who provided salivary cortisol samples before and after undergoing resting-state fMRI. We tested whether salivary cortisol by diagnosis interactions were associated with seed-based resting connectivity of the default mode (DMN) and salience and emotion (SN) networks using whole-brain, cluster-level corrected (p < .01) regression in SPM8.

RESULTS

Pre-scan cortisol predicted decreased (HC) and increased (rMDD) cross-network connectivity to the dorsal anterior cingulate, dorso-medial and lateral- prefrontal cortex, brain stem and cerebellum (all seeds) and precuneus (DMN seeds). By and large, pre/post-scan cortisol change predicted the same pattern of findings. In network analyses, cortisol predominantly predicted enhanced cross-network connectivity to cognitive control network regions in rMDD.

CONCLUSIONS

The association of cortisol with connections of default and salience networks to executive brain networks differs between individuals with and without a history of depression. Further investigation is needed to better understand the role of cortisol and related stress hormones as a potential primary and interactive driver of network coherence in depression.

Regenerative injection therapy and repetitive transcranial magnetic stimulation in primary fibromyalgia treatment: A comparative study

OBJECTIVE

This study compared the effectiveness of regenerative injection therapy (RIT), i.e. prolotherapy, and repetitive transcranial magnetic stimulation (rTMS) in the treatment of fibromyalgia syndrome.

PATIENTS AND METHODS

This study included 120 female, age-matched fibromyalgia patients. All patients underwent a clinical examination, pain assessment by VAS, assessment of tender points, psychiatric and functional assessment using the Beck Depression Inventory (BDI), Fibromyalgia Impact Questionnaire Revised (RFIQ), and measurement of cortical auditory evoked potentials CAEPs elicited at 1000 Hz. Patients were divided into two equal groups; Group 1 received prolotherapy three times, two weeks apart, and Group 2 received rTMS sessions every other day for one month. Assessment was performed before treatment, immediately after treatment, and one month later.

RESULTS

A significant improvement of pain measured by the mean score of VAS was remarked in Group 1 compared to Group 2 immediately after treatment and one month later. There was statistically significant difference of mean scores for the number of tender points in Group 1 compared to Group 2 after treatment and one month later. The patients improved functionally, with a statistically significant difference in mean score of RFIQ, in Group 1 compared to Group 2 one month after treatment. However, there was a significant difference in mean score of BDI in Group 2 compared to Group 1 after treatment and one month later. Further, CAEPs showed better improvement, with a significant difference in Group 2, one month after treatment.

CONCLUSION

RIT had the advantage in clinical and functional improvement in fibromyalgia patients, while rTMS had better results regarding depression and the cortical component of AEPs. These results might draw attention to the evaluability of a combination of both techniques for a better therapeutic response.

Comparative efficacy and acceptability of non-surgical brain stimulation for the acute treatment of major depressive episodes in adults: systematic review and network meta-analysis

OBJECTIVE

To estimate the comparative clinical efficacy and acceptability of non-surgical brain stimulation for the acute treatment of major depressive episodes in adults.

DESIGN

Systematic review with pairwise and network meta-analysis.

DATA SOURCES

Electronic search of Embase, PubMed/Medline, and PsycINFO up to 8 May 2018, supplemented by manual searches of bibliographies of several reviews (published between 2009 and 2018) and included trials.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Clinical trials with random allocation to electroconvulsive therapy (ECT), transcranial magnetic stimulation (repetitive (rTMS), accelerated, priming, deep, and synchronised), theta burst stimulation, magnetic seizure therapy, transcranial direct current stimulation (tDCS), or sham therapy.

MAIN OUTCOME MEASURES

Primary outcomes were response (efficacy) and all cause discontinuation (discontinuation of treatment for any reason) (acceptability), presented as odds ratios with 95% confidence intervals. Remission and continuous depression severity scores after treatment were also examined.

RESULTS

113 trials (262 treatment arms) that randomised 6750 patients (mean age 47.9 years; 59% women) with major depressive disorder or bipolar depression met the inclusion criteria. The most studied treatment comparisons were high frequency left rTMS and tDCS versus sham therapy, whereas recent treatments remain understudied. The quality of the evidence was typically of low or unclear risk of bias (94 out of 113 trials, 83%) and the precision of summary estimates for treatment effect varied considerably. In network meta-analysis, 10 out of 18 treatment strategies were associated with higher response compared with sham therapy: bitemporal ECT (summary odds ratio 8.91, 95% confidence interval 2.57 to 30.91), high dose right unilateral ECT (7.27, 1.90 to 27.78), priming transcranial magnetic stimulation (6.02, 2.21 to 16.38), magnetic seizure therapy (5.55, 1.06 to 28.99), bilateral rTMS (4.92, 2.93 to 8.25), bilateral theta burst stimulation (4.44, 1.47 to 13.41), low frequency right rTMS (3.65, 2.13 to 6.24), intermittent theta burst stimulation (3.20, 1.45 to 7.08), high frequency left rTMS (3.17, 2.29 to 4.37), and tDCS (2.65, 1.55 to 4.55). Network meta-analytic estimates of active interventions contrasted with another active treatment indicated that bitemporal ECT and high dose right unilateral ECT were associated with increased response. All treatment strategies were at least as acceptable as sham therapy.

CONCLUSIONS

These findings provide evidence for the consideration of non-surgical brain stimulation techniques as alternative or add-on treatments for adults with major depressive episodes. These findings also highlight important research priorities in the specialty of brain stimulation, such as the need for further well designed randomised controlled trials comparing novel treatments, and sham controlled trials investigating magnetic seizure therapy.