Safety and efficacy of repetitive transcranial magnetic stimulation in the treatment of depression: a critical appraisal of the last 10 years

Consensus review and considerations on TMS to treat depression: A comprehensive update endorsed by the National Network of Depression Centers, the Clinical TMS Society, and the International Federation of Clinical Neurophysiology

This article updates the prior 2018 consensus statement by the National Network of Depression Centers (NNDC) on the use of transcranial magnetic stimulation (TMS) in the treatment of depression, incorporating recent research and clinical developments. Publications on TMS and depression between September 2016 and April 2024 were identified using methods informed by PRISMA guidelines. The NNDC Neuromodulation Work Group met monthly between October 2022 and April 2024 to define important clinical topics and review pertinent literature. A modified Delphi method was used to achieve consensus. 2,396 abstracts and manuscripts met inclusion criteria for review. The work group generated consensus statements which include an updated narrative review of TMS safety, efficacy, and clinical features of use for depression. Considerations related to training, roles/responsibilities of providers, and documentation are also discussed. TMS continues to demonstrate broad evidence for safety and efficacy in treating depression. Newer forms of TMS are faster and potentially more effective than conventional repetitive TMS. Further exploration of targeting methods, use in special populations, and accelerated protocols is encouraged. This article provides an updated overview of topics relevant to the administration of TMS for depression and summarizes expert, consensus opinion on the practice of TMS in the United States.

Left dorsolateral prefrontal cortex activation can accelerate stress recovery: A repetitive transcranial stimulation study

In this study, a single high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) session was applied over the left dorsolateral prefrontal cortex (DLPFC) after a moderate-to-intense stressor to investigate whether left DLPFC stimulation could regulate cortisol concentration after stress induction. Participants were randomly divided into three groups (stress-TMS, stress, and placebo-stress). Stress was induced in both the stress-TMS and stress groups using the Trier Social Stress Test (TSST). The placebo-stress group received a placebo TSST. In the stress-TMS group, a single HF-rTMS session was applied over the left DLPFC after TSST. Cortisol was measured across the different groups, and each group's responses to the stress-related questionnaire were recorded. After TSST, both the stress-TMS and stress groups reported increased self-reported stress, state anxiety, negative affect, and cortisol concentration compared with the placebo-stress group, indicating that TSST successfully induced a stress response. Compared with the stress group, the stress-TMS group exhibited reduced cortisol levels at 0, 15, 30, and 45 min after HF-rTMS. These results suggest that left DLPFC stimulation after stress induction might accelerate the stress recovery.

Efficacy of Chinese herbal medicine on poststroke depression in animal models: A systematic review and meta-analysis

Background

Poststroke depression (PSD) is a common complication that can seriously affect patients' functional recovery and quality of life after a stroke. Various side effects have been found to be associated with the pharmacological therapies used for PSD. Studies have shown that Chinese herbal medicine (CHM) can effectively improve PSD-like behavior and neurological function in clinical and animal studies. The efficacy of CHM on PSD in animal models has not been systematically analyzed.

Methods

The following electronic databases were searched for articles published up to September 2022: PubMed, Web of Science, the Cochrane Library, and Embase. Studies that reported the efficacy of CHM in animals with PSD and were written in English were included. Depression-like behavior and the neurological deficit score were assessed as measures of efficacy. The included studies assessed depression-like behavior using sucrose preference, open-field, forced swimming, and tail suspension tests, as well as body weight. The Review Manager version 5.4 and STATA version 13.1 software packages were used for the meta-analysis. The standardized mean difference (SMD) with 95% confidence intervals was used to assess all the outcomes. Subgroup analyses were performed to explore the sources of heterogeneity. The Egger's test and funnel plots were used to assess the potential publication bias. Sensitivity analyses were used to identify the stability of the results.

Results

A total of 14 studies, including 12 CHMs involving 442 rats, fulfilled the inclusion criteria for meta-analysis. The pooled results showed that CHM significantly alleviated neurological deficits (-1.72 SMD, -2.47- -0.97) and was efficacious in improving the depression-like behavior of rats in the sucrose preference (2.08 SMD, 1.33-2.84), open-field (2.85 SMD, 1.88-3.83), forced swimming (-1.83 SMD, -2.23-1.44), and tail suspension tests (-1.35 SMD, -1.94-0.76).

Conclusion

Our results suggest that CHM could significantly improve depression-like behavior and neurological function in animals with PSD. The current results should be interpreted with caution because only animal studies were included.

Predictors of clinical response after rTMS treatment of patients suffering from drug-resistant depression

Repeated transcranial magnetic stimulation (rTMS) is a therapeutic brain-stimulation technique that is particularly used for drug-resistant depressive disorders. European recommendations mention the effectiveness of 30 to 64%. The failure rate of treatment is high and clinical improvement is visible only after a certain period of time. It would thus be useful to have indicators that could anticipate the success of treatment and more effectively guide therapeutic choices. We aimed to find predictive indicators of clinical improvement at 1 month after the start of rTMS treatment among the data collected during the care of patients with drug-resistant depression included in the Neuromodulation Unit of the Esquirol Hospital in Limoges since 2007. In total, 290 patients with a pharmaco-resistant depressive episode, according to the Hamilton Depression Rating Scale (HDRS) (score ≥8), before treatment who underwent a complete course of rTMS treatment and did not object to the use of their collected data were included. The clinical response in routine practice, corresponding to a decrease in the HDRS score of at least 50% from inclusion, was determined and complemented by interquartile analysis. A combination of factors predictive of clinical response during care, such as a short duration of the current depressive episode associated with a higher HDRS agitation item value (or a lower perceived sleepiness value) and a higher number of previous rTMS treatments, were identified as being useful in predicting the efficacy of rTMS treatment in routine clinical practice, thus facilitating the therapeutic choice for patients with drug-resistant depression.

The advances of post-stroke depression: 2021 update

Post-stroke depression (PSD) is one of common and serious sequelae of stroke. Approximately, one in three stroke survivors suffered from depression after stroke. It heavily affected functional rehabilitation, which leaded to poor quality of life. What is worse, it is strongly associated with high mortality. In this review, we aimed to derive a comprehensive and integrated understanding of PSD according to recently published papers and previous classic articles. Based on the considerable number of studies, we found that within 2 years incidence of PSD has a range from 11 to 41%. Many factors contribute to the occurrence of PSD, including the history of depression, stroke severity, lesion location, and so on. Currently, the diagnosis of PSD is mainly based on the DSM guidelines and combined with various depression scales. Unfortunately, we lack a unified mechanism to explain PSD which mechanisms now involve dysregulation of hypothalamic-pituitary-adrenal (HPA) axis, increased inflammatory factors, decreased levels of monoamines, glutamate-mediated excitotoxicity, and abnormal neurotrophic response. At present, both pharmacotherapy and psychological therapies are employed in treating PSD. Although great advance has been made by researchers, there are still a lot of issues need to be addressed. Especially, the mechanism of PSD is not completely clear.

Predictors of Response to Repetitive Transcranial Magnetic Stimulation in Depression: A Review of Recent Updates

Transcranial magnetic stimulation (TMS) has been increasingly used in the treatment of various neuropsychiatric disorders including depression over the past two decades. The responses to treatment with TMS are variable as found in the recent studies. Evidences suggest that various factors influence the outcome of depression treated with TMS. Understanding the predictors of response to TMS treatment in depression will guide the clinician in appropriate selection of patients for TMS treatment as well as needful modification in the TMS technique and protocol to have a better clinical outcome. This article comprehensively reviews the factors that predict the outcome of TMS treatment in depression.

Combining attentional bias modification with dorsolateral prefrontal rTMS does not attenuate maladaptive attentional processing

High frequency repetitive Transcranial Magnetic Stimulation (rTMS) over the left dorsolateral prefrontal cortex (DLPFC) has been shown to reduce depressive symptoms and improve cognitive biases such as attentional bias. One promising technique that may complement rTMS treatment is attentional bias modification (ABM) training, given the similarity in modulating attentional bias and affecting neuronal activity. We tested whether the combination of rTMS treatment and ABM training in a single session would attenuate maladaptive attentional processing and improve mood in participants with subclinical depressive symptoms. To this end, 122 healthy participants were randomly assigned to one of four groups, receiving either a single rTMS treatment, a single ABM treatment, a combination of rTMS and ABM or a sham treatment. Of these 122 participants, 72 showed a heightened BDI-II score (between 9 and 25) and were included in our main analyses. In our subclinical (≥9 and ≤25 BDI-II) sample, a single combination treatment of rTMS and ABM training induced no significant changes in attentional bias, attentional control or mood, nor did rTMS alone affect attentional bias systematically. We discuss these null findings in light of the task specifics and relate them to the ongoing discussion on ABM training in depression.

Repetitive Transcranial Magnetic Stimulation and Treatment-emergent Mania and Hypomania: A Review of the Literature

BACKGROUND

This review focuses on treatment-emergent mania/hypomania (TEM) associated with repetitive transcranial magnetic stimulation (rTMS).

METHODS

English-language studies involving possible rTMS-induced mania/hypomania published between 1966 and 2015 were retrieved through a Medline search using the search terms mania, hypomania, mixed affective state, treatment-emergent, repetitive transcranial magnetic stimulation, and rTMS. Fifteen case series and controlled studies describing TEM associated with rTMS treatment have been published involving 24 individuals, most of whom were diagnosed with either bipolar I or II disorder or major depressive disorder.

RESULTS

rTMS has been shown to possibly induce manic or hypomanic episodes in patients with depression, who are sometimes also taking antidepressants. Both high-frequency and low-frequency rTMS with different stimulus parameters may be associated with TEM in both males and females.

CONCLUSIONS

Given these findings, it is highly recommended that patients with bipolar disorder who are experiencing a depressive episode be prescribed a mood stabilizer and that patients diagnosed with major depressive disorder be reevaluated to consider the possibility that they might have bipolar disorder, before rTMS treatment is initiated. If TEM occurs, discontinuation of rTMS should be considered, while continuing mood-stabilizing medications. Further research is needed concerning the underlying neurobiological mechanisms and epidemiologic characteristics of TEM associated with rTMS.

Neurostimulation techniques in the treatment of nicotine dependence: A review

OBJECTIVE

Nicotine dependence accounts for significant mortality, morbidity, and socio-economic burdens. It remains a significant public health concern since it is among the leading causes of mortality worldwide and of preventable deaths in developed countries. Despite the availability of approved medications to treat nicotine dependence, along with cognitive behavioral therapy, only 6% of the total number of smokers who report wanting to quit each year are successful in doing so for more than a month mostly with poor abstinence rates. Urgent therapeutic alternatives are therefore needed such as neurostimulation techniques. The purpose of this review is to describe studies that have evaluated the safety and efficacy of these techniques for the treatment of nicotine dependence.

METHODS

The electronic literature on repetitive transcranial magnetic stimulation, theta-burst stimulation, deep transcranial magnetic stimulation, transcranial direct current stimulation, magnetic seizure therapy, electroconvulsive therapy, cranial electro-stimulation, and deep brain stimulation in the treatment of nicotine addiction were reviewed.

RESULTS

Most of these studies found that some of these neurostimulation techniques are safe and potentially effective in the reduction of craving to nicotine as well as in the reduction of cigarette consumption.

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

Given the promising results of some of the studies particularly with repetitive transcranial magnetic stimulation, theta-burst stimulation, transcranial direct current stimulation and, possibly, deep transcranial magnetic stimulation, future controlled studies with larger samples, and optimal stimulus parameters should be designed to confirm these findings. (Am J Addict 2016;25:436-451).

Neuromodulation of Attentional Control in Major Depression: A Pilot DeepTMS Study

While Major Depressive Disorder (MDD) is primarily characterized by mood disturbances, impaired attentional control is increasingly identified as a critical feature of depression. Deep transcranial magnetic stimulation (deepTMS), a noninvasive neuromodulatory technique, can modulate neural activity and induce neuroplasticity changes in brain regions recruited by attentional processes. This study examined whether acute and long-term high-frequency repetitive deepTMS to the dorsolateral prefrontal cortex (DLPFC) can attenuate attentional deficits associated with MDD. Twenty-one MDD patients and 26 matched control subjects (CS) were administered the Beck Depression Inventory and the Sustained Attention to Response Task (SART) at baseline. MDD patients were readministered the SART and depressive assessments following a single session (n = 21) and after 4 weeks (n = 13) of high-frequency (20 Hz) repetitive deepTMS applied to the DLPFC. To control for the practice effect, CS (n = 26) were readministered the SART a further two times. The MDD group exhibited deficits in sustained attention and cognitive inhibition. Both acute and long-term high-frequency repetitive frontal deepTMS ameliorated sustained attention deficits in the MDD group. Improvement after acute deepTMS was related to attentional recovery after long-term deepTMS. Longer-term improvement in sustained attention was not related to antidepressant effects of deepTMS treatment.

Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS)

A group of European experts was commissioned to establish guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS) from evidence published up until March 2014, regarding pain, movement disorders, stroke, amyotrophic lateral sclerosis, multiple sclerosis, epilepsy, consciousness disorders, tinnitus, depression, anxiety disorders, obsessive-compulsive disorder, schizophrenia, craving/addiction, and conversion. Despite unavoidable inhomogeneities, there is a sufficient body of evidence to accept with level A (definite efficacy) the analgesic effect of high-frequency (HF) rTMS of the primary motor cortex (M1) contralateral to the pain and the antidepressant effect of HF-rTMS of the left dorsolateral prefrontal cortex (DLPFC). A Level B recommendation (probable efficacy) is proposed for the antidepressant effect of low-frequency (LF) rTMS of the right DLPFC, HF-rTMS of the left DLPFC for the negative symptoms of schizophrenia, and LF-rTMS of contralesional M1 in chronic motor stroke. The effects of rTMS in a number of indications reach level C (possible efficacy), including LF-rTMS of the left temporoparietal cortex in tinnitus and auditory hallucinations. It remains to determine how to optimize rTMS protocols and techniques to give them relevance in routine clinical practice. In addition, professionals carrying out rTMS protocols should undergo rigorous training to ensure the quality of the technical realization, guarantee the proper care of patients, and maximize the chances of success. Under these conditions, the therapeutic use of rTMS should be able to develop in the coming years.

rTMS in the treatment of drug addiction: an update about human studies

Drug addiction can be a devastating and chronic relapsing disorder with social, psychological, and physical consequences, and more effective treatment options are needed. Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation technique that has been assessed in a growing number of studies for its therapeutic potential in treating addiction. This review paper offers an overview on the current state of clinical research in treating drug addiction with rTMS. Because of the limited research in this area, all studies (including case reports) that evaluated the therapeutic use of rTMS in nicotine, alcohol, or illicit drug addiction were included in this review. Papers published prior to December 2012 were found through an NCBI PubMed search. A total of eleven studies were identified that met review criteria. There is nascent evidence that rTMS could be effective in reducing cocaine craving and nicotine and alcohol craving and consumption and might represent a potential therapeutic tool for treating addiction. Further studies are needed to identify the optimal parameters of stimulation for the most effective treatment of drug addiction, to improve our comprehension of the treatment neurophysiological effects, and to conduct rigorous, controlled efficacy studies with adequate power.

Effect of five-consecutive-day exposure to an anxiogenic stressor on sleep-wake activity in rats

Repeated exposure to an anxiogenic stressor (AS) is a known environmental factor for the development of depression, yet the progression of sleep-wake (S-W) changes associated with the onset of AS-induced depression (ASID) is not completely understood. Thus, the aim of this study was to identify these progressive S-W changes by developing ASID in rats, via repeated exposure to an AS, and compare this ASID-associated sleep phenotype with the sleep phenotype of human depression. To achieve this aim, rats were first recorded for a 6 h period of baseline S-W activity without AS. Then, rats were subjected to 5 days of AS [Day 1: inescapable foot-shock; 5 trials of 3 s foot-shocks (1.0 mA) at 3 min intervals; Days 3–5: 15 trials of 5 s foot-shocks at 45 s intervals]. S-W activity was recorded for 6 h immediately after each AS treatment session. Two days later rats were again recorded for 6 h of S-W activity, but with no exposure to the AS (NASD). Compared to the baseline day: Day 1 of AS (ASD-1) increased wakefulness, slow-wave sleep (SWS) latency, and rapid-eye movement (REM) sleep latency, but decreased the total amount of REM sleep; ASD-2 animals remained awake throughout the 6 h S-W recording period; ASD-3, ASD-4, and ASD-5 (ASDs-3–5) decreased wakefulness, SWS latency, and REM sleep latency, but increased the total amount of REM sleep. Interestingly, these results reveal that initial exposure to the AS versus later, repeated exposure to the AS produced opposing S-W changes. On NASD, animals exhibited baseline-like S-W activity, except slightly less REM sleep. These results suggest that repeated AS produces a sleep phenotype that resembles the sleep phenotype of depression in humans, but consistent re-exposure to the AS is required. These results are promising because the methodological simplicity and reversibility of the ASID-associated S-W phenotype could be more advantageous than other animal models for studying the pathophysiological mechanisms that underlie the expression of ASID.

Addiction

Drug and alcohol addiction is a debilitating disorder characterized by persistent drug-seeking behaviors despite negative physiological, medical, or social consequences. Neurobiological models of addiction propose that the reinforcing effects of addictive drugs are associated with altered neurotransmission within the reward 'mesocorticolimbic' circuitry in the brain. Immense efforts are therefore designed to target the mesocorticolimbic circuitry in attenuating drug dependence and addiction-related behaviors. Yet, to date, most addiction treatments have demonstrated only limited success in reducing addiction-related behaviors. Accumulating and compelling evidence suggests that novel nonsurgical brain stimulation techniques, such as transcranial magnetic stimulation and transcranial direct current stimulation, could serve as promising tools for indexing altered neurotransmission associated with repetitive drug use, and moreover, may hold therapeutic potential for the treatment of drug dependence and addiction-related behaviors. This chapter reviews and discusses the current and potential applications of such techniques in the study and treatment of addiction; we focus on a number of common drugs of abuse, including nicotine, alcohol, cocaine, cannabis, and ecstasy.

Repetitive transcranial magnetic stimulation in psychiatry

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive and relatively painless tool that has been used to study various cognitive functions as well as to understand the brain–behavior relationship in normal individuals as well as in those with various neuropsychiatric disorders. It has also been used as a therapeutic tool in various neuropsychiatric disorders because of its ability to specifically modulate distinct brain areas. Studies have shown that repeated stimulation at low frequency produces long-lasting inhibition, which is called as long-term depression, whereas repeated high-frequency stimulation can produce excitation through long-term potentiation. This paper reviews the current status of rTMS as an investigative and therapeutic modality in various neuropsychiatric disorders. It has been used to study the cortical and subcortical functions, neural plasticity and brain mapping in normal individuals and in various neuropsychiatric disorders. rTMS has been most promising in the treatment of depression, with an overall milder adverse effect profile compared with electroconvulsive therapy. In other neuropsychiatric disorders such as schizophrenia, mania, epilepsy and substance abuse, it has been found to be useful, although further studies are required to establish therapeutic efficacy. It appears to be ineffective in the treatment of obsessive compulsive disorder. There is a paucity of studies of efficacy and safety of rTMS in pediatric and geriatric population. Although it appears safe, further research is required to optimize its efficacy and reduce the side-effects. Magnetic seizure therapy, which involves producing seizures akin to electroconvulsive therapy, appears to be of comparable efficacy in the treatment of depression with less cognitive adverse effects.

Safety and efficacy of repetitive transcranial magnetic stimulation in the treatment of obsessive-compulsive disorder: a review

OBJECTIVES

Obsessive-compulsive disorder (OCD) is a chronic, often severe, neuropsychiatric disorder leading to a dramatic impairment in interpersonal and occupational functions. rTMS has been tried out in several studies in patients with OCD with different characteristics. In this paper, we review the safety and efficacy of rTMS in the treatment of mostly severe resistant OCD.

METHODS

A review of the English literature from 1966 to 2010 pertaining to rTMS in the treatment of OCD was conducted using MEDLINE by selectively entering the search terms "transcranial magnetic stimulation", "repetitive transcranial magnetic stimulation", "obsessive-compulsive disorder" and "OCD". Twelve studies including open and randomized, sham-controlled trials were included in this review.

RESULTS

Although available data about the use of rTMS in OCD treatment are quite heterogeneous in terms of sample size, study design, stimulus parameters used and stimulation areas targeted, promising findings regarding rTMS efficacy appeared for two structures based on recent controlled studies: the supplementary motor area and the orbitofrontal cortex. On the other hand, rTMS of the dorsolateral prefrontal cortex is not significantly effective when compared to sham rTMS.

CONCLUSIONS

Three target areas have already been selected of which the supplementary motor area in particular and the orbitofrontal cortex seem to be the most promising in terms of potential efficacy and could more accurately be targeted with the help of neuronavigational techniques. Larger randomized controlled trials should be conducted in order to better clarify the therapeutic role of rTMS in OCD.

Systematic review of parameters of stimulation, clinical trial design characteristics, and motor outcomes in non-invasive brain stimulation in stroke

INTRODUCTION/OBJECTIVES

Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation are two powerful non-invasive neuromodulatory therapies that have the potential to alter and evaluate the integrity of the corticospinal tract. Moreover, recent evidence has shown that brain stimulation might be beneficial in stroke recovery. Therefore, investigating and investing in innovative therapies that may improve neurorehabilitative stroke recovery are next steps in research and development. Participants/Materials and Methods: This article presents an up-to-date systematic review of the treatment effects of rTMS and tDCS on motor function. A literary search was conducted, utilizing search terms "stroke" and "transcranial stimulation." Items were excluded if they failed to: (1) include stroke patients, (2) study motor outcomes, or (3) include rTMS/tDCS as treatments. Other exclusions included: (1) reviews, editorials, and letters, (2) animal or pediatric populations, (3) case reports or sample sizes ≤2 patients, and (4) primary outcomes of dysphagia, dysarthria, neglect, or swallowing.

RESULTS

Investigation of PubMed English Database prior to 01/01/2012 produced 695 applicable results. Studies were excluded based on the aforementioned criteria, resulting in 50 remaining studies. They included 1314 participants (1282 stroke patients and 32 healthy subjects) evaluated by motor function pre- and post-tDCS or rTMS. Heterogeneity among studies' motor assessments was high and could not be accounted for by individual comparison. Pooled effect sizes for the impact of post-treatment improvement revealed consistently demonstrable improvements after tDCS and rTMS therapeutic stimulation. Most studies provided limited follow-up for long-term effects.

CONCLUSION

It is apparent from the available studies that non-invasive stimulation may enhance motor recovery and may lead to clinically meaningful functional improvements in the stroke population. Only mild to no adverse events have been reported. Though results have been positive results, the large heterogeneity across articles precludes firm conclusions.

Meta-Review of Metanalytic Studies with Repetitive Transcranial Magnetic Stimulation (rTMS) for the Treatment of Major Depression

Background:

Major Depression (MD) and treatment-resistant depression (TRD) are worldwide leading causes of disability and therapeutic strategies for these impairing and prevalent conditions include pharmacological augmentation strategies and brain stimulation techniques. In this perspective, repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique with a favorable profile of tolerability which, despite being recently approved by the Food and Drug Administration (FDA) for the treatment of patients with medication-refractory unipolar depression, still raises some doubts about most effective parameters of stimulation.

Methods:

A literature search was performed using PubMed for the years 2001 through February 2011 in order to review meta-analytic studies assessing efficacy and safety issues for rTMS in depressive disorders. Fifteen meta-analyses were identified and critically discussed in order to provide an updated and comprehensive overview of the topic with specific emphasis on potentially optimal parameters of stimulation.

Results:

First meta-analyses on the efficacy of rTMS for the treatment of MD and TRD have shown mixed results. On the other hand, more recent meta-analytic studies seem to support the antidepressant efficacy of the technique to a greater extent, also in light of longer periods of stimulation (e.g. > 2 weeks).

Conclusion:

rTMS seems to be an effective and safe brain stimulation technique for the treatment of medication refractory depression. Nevertheless, further studies are needed to better define specific stimulation-related issues, such as duration of treatment as well as durability of effects and predictors of response.

Effects of repetitive transcranial magnetic stimulation of the dorsolateral prefrontal cortex on the attentional processing of emotional information in major depression: a pilot study

Repetitive transcranial magnetic stimulation (rTMS) is as a promising therapeutic tool for major depressive disorder. However, the degree of clinical improvement following rTMS treatment still remains questionable. This pilot study aimed at investigating potential working mechanisms of rTMS by examining the effects on attentional processing towards negative information, a proposed underlying cognitive vulnerability factor for depression. The antidepressant effect of high-frequency (10 Hz) rTMS over the left dorsolateral prefrontal cortex and possible effects on the inhibitory processing of emotional information was assessed in a sample of 14 depressed patients immediately after the first stimulation session and at the end of a 2-week treatment period. One session of rTMS caused neither significant self-reported mood changes, nor improvements in inhibitory control towards negative information. After a 10-day treatment period, nine out of our 14 patients demonstrated significant mood improvements, as indexed by a reduction of more than 50% on the Hamilton depression rating scale. Responders also demonstrated significant improvements in the inhibitory processing of negative information. This study contributed to the existing evidence of the antidepressant effect of rTMS in the treatment of depression and additionally was able to demonstrate improvements in underlying deficiencies in inhibitory processes towards negative information.

HF-rTMS treatment decreases psychomotor retardation in medication-resistant melancholic depression

Repetitive Transcranial Magnetic Stimulation (rTMS) applied to the left dorsolateral prefrontal cortex (DLPFC) might be a promising treatment strategy for depression. As one of the key features of melancholic depression is disturbances in psychomotor activity, we wanted to evaluate whether HF-rTMS treatment could influence psychomotor symptoms. Twenty antidepressant-free unipolar melancholic depressed patients, all at least stage III medication-resistant, were studied. All were treated with 10 sessions of High-Frequency (HF)-rTMS applied to the left dorsolateral prefrontal cortex (DLPFC) under MRI guidance. Forty percent of the patients showed a reduction of at least 50% on their initial 17-item Hamilton Depression Rating Score (HDRS) scale and were defined as clinical responders. Regardless of clinical outcome HF-rTMS treatment resulted in significant decreases on the Depressive Retardation Rating Scale (DRRS) scores. Although this was an open study in a relatively small sample, our results suggest that HF-rTMS might act on the 'psychomotor' level and these findings could add some further information as to why this kind of treatment can be beneficial for severely depressed patients of the melancholic subtype.

rTMS for adolescents: Safety and efficacy considerations

In light of both the FDA's clearance of repetitive transcranial magnetic stimulation (rTMS) for adult major depressive disorder and concerns about safety and efficacy of existing antidepressant therapies for adolescent depression, there is increasing interest in rTMS as a novel treatment for adolescent depression. We reviewed English-language studies using rTMS in persons under the age of 18, yielding 6 published reports. Because rTMS is typically delivered at or above 1 Hz for psychiatric indications, our search was confined to these frequencies. Also included are studies involving rTMS above 1 Hz for non-psychiatric indications. Articles were retrieved from the MEDLINE database. There were 19 reported subjects under age 18 who have been administered rTMS at a frequency above 1 Hz: 10 for major depression, 5 for spastic cerebral palsy and 4 for epilepsia partialis continua. We found that most subjects responded favorably to rTMS and no adverse events have been reported. However data are insufficient for drawing firm conclusions about safety and efficacy. Further studies of rTMS as a treatment for adolescent depression are warranted.

[Electrostimulation techniques in treatment for severe depression]

Electroconvulsivotherapy represents a key indication for severe Major Depressive Episode (MDE). However, an hospitalization with a general anaesthesia allowing a seizure induction followed by an almost systematic post-epileptic delirium justifies the development of other brain electrostimulation techniques. Trans-cranial Magnetic Stimulation (TMS) is a technique which offers to transform an electromagnetic field within the brain in an electric one. This therapeutic has been approved in 2008 in the MDE indication by the Food and Drug Administration. However a better knowledge of brain stimulation parameters such as the number of sequences, intensity, frequency, and the brain target, is necessary. Indeed it could enable to get some more homogeneous clinical results which will drive to the use of this technique in daily practice. Neurosurgical procedures represent also a stake for a better treatment of severe chronic and resistant depression. Whereas Vagus Nerve Stimulation (DBS) failed to be developed in France, Deep Brain Stimulation (DBS) is currently under development in this indication with some promising preliminary results.

Brain stimulation in the study and treatment of addiction

Addiction is a devastating and chronically relapsing disorder. Repeated drug administration induces neuroadaptations associated with abnormal dopaminergic activity in the mesocorticolimbic circuitry, resulting in altered cortical neurotransmission and excitability. Electrical stimulation of specific brain regions can be used in animal models and humans to induce local activation or disruption of specific circuitries or alter neuronal excitability and cause neuroadaptations. Non-surgical stimulation of specific brain regions in human addicts can be achieved by transcranial magnetic stimulation (TMS). TMS is used for transient stimulation or disruption of neural activity in specific cortical regions, which can be used to assess cortical excitability, and to induce changes in cortical excitability. Moreover, it is suggested that repeated stimulation can cause long-lasting neuroadaptations. Therefore, TMS paradigms were used in some studies to assess the presence of altered cortical excitability associated with chronic drug consumption, while other studies have begun to assess the therapeutic potential of repetitive TMS. Similarly, transcranial direct current stimulation (tDCS) is used to modulate neuronal resting membrane potential in humans and alter cortical excitability. The current review describes how these brain stimulation techniques have recently been used for the study and treatment of addiction in animal models and humans.

The value of neuronavigated rTMS for the treatment of depression

Repetitive transcranial magnetic stimulation (rTMS) has been increasingly evaluated as a therapeutic tool for the treatment of depression, using various stimulation parameters and protocols. Heterogeneous results have been reported with regard to clinical outcome, at least partly due to the variety of procedures for coil placement above the desired site of stimulation. This article reviews the strategies for coil positioning in the treatment of depression. Considering preliminary clinical evidence, neuronavigated rTMS appears desirable to treat depression, compared to the standard targeting procedure (5cm anterior to the motor cortex). Coil positioning strategy might improve in the future by taking into consideration the individual abnormalities revealed by functional neuroimaging data.

Influence of high-frequency repetitive transcranial magnetic stimulation over the dorsolateral prefrontal cortex on the inhibition of emotional information in healthy volunteers

BACKGROUND

Evidence suggests that repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (DLPFC) might be a promising new treatment procedure for depression. However, underlying working mechanisms of this technique are yet unclear. Multiple sessions of rTMS may--apart from the reported antidepressant effects--cause primary improvements in attentional control over emotional information, modulated by changes in cortical brain excitability within stimulated prefrontal regions.

METHOD

In two experiments, we examined the temporary effects of high-frequency (HF) rTMS (10 Hz) applied over the left and right DLPFC on the attentional processing of emotional information and self-reported mood within samples of healthy volunteers.

RESULTS

The present study showed that one session of HF-rTMS over the right DLPFC produces instant impairments in the ability to inhibit negative information, in line with a characteristic cognitive vulnerability found in depressive pathology, whereas HF-rTMS of the left DLPFC did not lead to significant changes in attentional control. These effects could not be attributed to mood changes.

CONCLUSIONS

The findings of the present study may suggest a specific involvement of the right DLPFC in the attentional processing of emotional information.

Repetitive transcranial magnetic stimulation for treatment of medication-resistant depression in older adults: a case series

The antidepressant effects of repetitive transcranial magnetic stimulation (rTMS) are well documented, but studies to date have produced heterogeneous results in late-life depression.

OBJECTIVE

To address this matter, we evaluated the efficacy of both high- and low-frequency rTMS delivered to the prefrontal cortex of older adults with treatment-resistant major depression.

METHODS

Forty-nine older adults (69 +/- 6.7 years) with treatment-refractory major depressive disorders underwent a series of rTMS treatments as an adjuvant to pharmacotherapy. Patients received high-frequency rTMS delivered to the left dorsolateral prefrontal cortex, low-frequency stimulation to the right dorsolateral prefrontal cortex, or a combination thereof, at 80-110% of the motor threshold.

RESULTS

There was a modest, but statistically significant, mean reduction (24.7%) in Hamilton Depression Rating Scale (HDRS) scores from baseline to the end of treatment. Nine patients were classified as responders (50% HDRS reduction), and 4 patients reached remission status (final HDRS score <8). Similar improvements in HDRS scores were observed for high- and low-frequency rTMS. Treatment was generally well tolerated, and no serious adverse effects were reported.

CONCLUSIONS

The findings support the contention that in older adults with treatment-refractory depression, rTMS can be an effective treatment alternative for some patients.

Antidepressant therapy in post-stroke depression

BACKGROUND

About 40% of patients with stroke will develop depression at some stage after the acute event. Post-stroke depression (PSD) is associated with a poor prognosis. Depressed patients have more severe deficits in activities of daily living, a worse functional outcome, more severe cognitive deficits and increased mortality as compared to stroke patients without depression.

OBJECTIVE

This review will focus on available controlled trials of treatment for PSD.

METHODS

An unsystematic review of recent studies for the treatment of PSD.

RESULTS

Randomized controlled trials have demonstrated the efficacy of sertraline, citalopram and nortriptyline to treat post-stroke depression. Whether antidepressant medication may help to prevent post-stroke depression and decrease post-stroke mortality will require further controlled studies.

A randomized controlled feasibility and safety study of deep transcranial magnetic stimulation

OBJECTIVE

The H-coils are a new development in transcranial magnetic stimulation (TMS) research, allowing direct stimulation of deeper neuronal pathways than does standard TMS. This study assessed possible health risks, and some cognitive and emotional effects, of two H-coil versions designed to stimulate deep portions of the prefrontal cortex, using several stimulation frequencies.

METHODS

Healthy volunteers (n=32) were randomly assigned to one of four groups: each of two H-coil designs (H1/H2), standard figure-8 coil, and sham-coil control. Subjects were tested in a pre-post design, during three increasing (single pulses, 10 Hz, and 20 Hz) stimulation sessions, as well as 24-36 h after the last stimulation.

RESULTS

The major finding of the present study is that stimulation with the novel H-coils was well tolerated, with no adverse physical or neurological outcomes. Computerized cognitive tests found no deterioration in cognitive functions, except for a transient short-term effect of the H1-coil on spatial recognition memory on the first day of rTMS (but not in the following treatment days). On the other hand, spatial working memory was transiently improved by the H2-coil treatment. Finally, the questionnaires showed no significant emotional or mood alterations, except for reports on 'detachment' experienced by subjects treated with the H1-coil.

CONCLUSIONS

This study provides additional evidence for the feasibility and safety of the two H-coil designs (H1/H2).

SIGNIFICANCE

The H-coils offer a safe new tool with potential for both research and clinical applications for psychiatric and neurological disorders associated with dysfunctions of deep brain regions.

The role of neurotrophic factors in adult hippocampal neurogenesis, antidepressant treatments and animal models of depressive-like behavior

Major depressive disorder (MDD) is characterized by structural and neurochemical changes in limbic structures, including the hippocampus, that regulate mood and cognitive functions. Hippocampal atrophy is observed in patients with depression and this effect is blocked or reversed by antidepressant treatments. Brain-derived neurotrophic factor and other neurotrophic/growth factors are decreased in postmortem hippocampal tissue from suicide victims, which suggests that altered trophic support could contribute to the pathophysiology of MDD. Preclinical studies demonstrate that exposure to stress leads to atrophy and cell loss in the hippocampus as well as decreased expression of neurotrophic/growth factors, and that antidepressant administration reverses or blocks the effects of stress. Accumulating evidence suggests that altered neurogenesis in the adult hippocampus mediates the action of antidepressants. Chronic antidepressant administration upregulates neurogenesis in the adult hippocampus and this cellular response is required for the effects of antidepressants in certain animal models of depression. Here, we review cellular (e.g. adult neurogenesis) and behavioral studies that support the neurotrophic/neurogenic hypothesis of depression and antidepressant action. Aberrant regulation of neuronal plasticity, including neurogenesis, in the hippocampus and other limbic nuclei may result in maladaptive changes in neural networks that underlie the pathophysiology of MDD.

Low frequency repetitive transcranial magnetic stimulation over premotor cortex can improve cortical tremor

OBJECTIVE

To examine the effects of a 30 min, 1 Hz subthreshold rTMS in a case of cortical tremor which is caused by hyperexcitability of sensorimotor cortex.

METHODS

Stimulation was applied over primary and, in a second time, over premotor cortex (M1 and PMC, respectively). Tremor was monitored by accelerometers placed on the index fingers of hands outstretched, before and several times after rTMS. Each rTMS session consisted of 1800 pulses delivered at 1 Hz with an intensity of 90% of resting motor threshold.

RESULTS

PMC but not M1 stimulation led to a decrease of the postural tremor (90% decrease of acceleration total spectral power). This functional benefit was associated to normalization of electrophysiologic parameters (short-interval intracortical inhibition and cortical silent period duration). Moreover, when stimulating PMC during two daily sessions, improvement of the tremor was longer than one day stimulation and this benefit was associated with functional improvement.

CONCLUSIONS

This study shows that 1 Hz rTMS over premotor cortex can improve cortical tremor.

SIGNIFICANCE

These results raise the interest of the motor cortical stimulation as a possible therapeutic target for treatment of action tremor.