Add-on high frequency deep transcranial magnetic stimulation (dTMS) to bilateral prefrontal cortex reduces cocaine craving in patients with cocaine use disorder

Neurovascular effects of cocaine: relevance to addiction

Cocaine is a highly addictive drug, and its use is associated with adverse medical consequences such as cerebrovascular accidents that result in debilitating neurological complications. Indeed, brain imaging studies have reported severe reductions in cerebral blood flow (CBF) in cocaine misusers when compared to the brains of healthy non-drug using controls. Such CBF deficits are likely to disrupt neuro-vascular interaction and contribute to changes in brain function. This review aims to provide an overview of cocaine-induced CBF changes and its implication to brain function and to cocaine addiction, including its effects on tissue metabolism and neuronal activity. Finally, we discuss implications for future research, including targeted pharmacological interventions and neuromodulation to limit cocaine use and mitigate the negative impacts.

Non-invasive brain stimulation for patients and healthy subjects: Current challenges and future perspectives

Non-invasive brain stimulation (NIBS) techniques have a rich historical background, yet their utilization has witnessed significant growth only recently. These techniques encompass transcranial electrical stimulation and transcranial magnetic stimulation, which were initially employed in neuroscience to explore the intricate relationship between the brain and behaviour. However, they are increasingly finding application in research contexts as a means to address various neurological, psychiatric, and neurodegenerative disorders. This article aims to fulfill two primary objectives. Firstly, it seeks to showcase the current state of the art in the clinical application of NIBS, highlighting how it can improve and complement existing treatments. Secondly, it provides a comprehensive overview of the utilization of NIBS in augmenting the brain function of healthy individuals, thereby enhancing their performance. Furthermore, the article delves into the points of convergence and divergence between these two techniques. It also addresses the existing challenges and future prospects associated with NIBS from ethical and research standpoints.

Managing substance use in patients receiving therapeutic repetitive transcranial magnetic stimulation: A scoping review

Repetitive Transcranial Magnetic Stimulation (rTMS) is an invaluable treatment option for neuropsychiatric disorders. Co-occurring recreational and nonmedical substance use can be common in those presenting for rTMS treatment, and it is unknown how it may affect the safety and efficacy of rTMS for the treatment of currently approved neuropsychiatric indications. This scoping review aimed to map the literature on humans receiving rTMS and had a history of any type of substance use. The search identified 274 articles providing information on inclusion/exclusion criteria, withdrawal criteria, safety protocols, type of rTMS and treatment parameters, adverse events and effect on primary outcomes that related to substance use. There are neurophysiological effects of substance use on cortical excitability, although the relevance to clinical rTMS practice is unknown. The current literature supports the safety and feasibility of delivering rTMS to those who have co-occurring neuropsychiatric disorder and substance use. However, specific details on how varying degrees of substance use alters the safety, efficacy, and mechanisms of rTMS remains poorly described.

Transcranial Magnetic Stimulation as a Tool to Promote Smoking Cessation and Decrease Drug and Alcohol Use

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive, drug-free, neural-circuit-based therapeutic tool that was recently cleared by the United States Food and Drug Associate for the treatment of smoking cessation. TMS has been investigated as a tool to reduce consumption and craving for many other substance use disorders (SUDs). This review starts with a discussion of neural networks involved in the addiction process. It then provides a framework for the therapeutic efficacy of TMS describing the role of executive control circuits, default mode, and salience circuits as putative targets for neuromodulation (via targeting the DLPFC, MPFC, cingulate, and insula bilaterally). A series of the largest studies of TMS in SUDs are listed and discussed in the context of this framework. Our review concludes with an assessment of the current state of knowledge regarding the use of rTMS as a therapeutic tool in reducing drug, alcohol, and nicotine use and identifies gaps in the literature that need to be addressed in future studies. Namely, while the presumed mechanism through which TMS exerts its effects is by modulating the functional connectivity circuits involved in executive control and salience of drug-related cues, it is also possible that TMS has direct effects on subcortical dopamine, a hypothesis that could be explored in greater detail with PET imaging.

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.

Effects of 10 add-on HF-rTMS treatment sessions on alcohol use and craving among detoxified inpatients with alcohol use disorder: a randomized sham-controlled clinical trial

BACKGROUND AND AIMS

Alcohol use disorder (AUD) is a chronic disorder with high relapse rates. There are currently few clinical trials of high frequency repetitive transcranial magnetic stimulation (HF-rTMS) to reduce alcohol use among AUD patients, and results are mixed. The current study tested the effect of 10 add-on sessions of HF-rTMS over the right dorsolateral pre-frontal cortex (DLPFC) on alcohol use and craving.

DESIGN

Single-center, single blind sham-controlled parallel-group RCT (n = 80), with 3 and 6 months follow-up.

SETTING

Clinical treatment center in Amsterdam, the Netherlands.

PARTICIPANTS

Eighty detoxified and abstinent AUD inpatients in clinical treatment (20 females, average age = 44.35 years).

INTERVENTION

Ten sessions of active or sham HF-rTMS (60 10 Hz trains of 5 sec at 110% motor threshold) over the right DLPFC on 10 consecutive work-days.

MEASUREMENTS

The primary outcome measure is the number of abstinent days over 6-month follow-up (FU). Secondary outcome measures are craving over 6-month FU (alcohol urge questionnaire and obsessive-compulsive drinking scale), time to first relapse over 6-month FU and grams of alcohol consumed over 6-month FU. Additional outcome measures: full abstinence over 6-month FU and treatment success over 12-month FU.

FINDINGS

HF-rTMS did not affect the number of abstinent days over 6 months FU [sham = 124 ± 65.9 days, active = 115 ± 69.8 days, difference: 9 days, 95% confidence interval (CI) = Poisson model: 0.578-3.547]. Moreover, HF-rTMS did not affect craving (AUQ/OCDS) (sham = 15.38/5.28, active = 17.48/4.75, differences = 2.1/-0.53, 95% CI mixed-effects model = -9.14 to 2.07/-1.44 to 2.40).

CONCLUSIONS

There was no clear evidence that high-frequency repetitive transcranial magnetic stimulation over the right dorsolateral pre-frontal cortex treatment has a long-term positive effect on alcohol use or craving as add-on treatment for alcohol use disorder. High treatment response at 6-month follow-up could have limited the possibility to find an effect.

Substance Use and Addiction in Athletes: The Case for Neuromodulation and Beyond

Substance use, misuse and use disorders continue to be major problems in society as a whole and athletes are certainly not exempt. Substance use has surrounded sports since ancient times and the pressures associated with competition sometimes can increase the likelihood of use and subsequent misuse. The addiction field as a whole has very few answers to how to prevent and secondarily treat substance use disorders and the treatments overall do not necessarily agree with the role of being an athlete. With concerns for side effects that may affect performance coupled with organizational rules and high rates of recidivism in the general population, newer treatments must be investigated. Prevention strategies must continue to be improved and more systems need to be in place to find and treat any underlying causes leading to these behaviors. This review attempts to highlight some of the data regarding the field of substance misuse and addiction in the athletic population as well as explore possible future directions for treatment including Neuromodulation methods and Ketamine. There is a need for more rigorous, high-quality studies to look at addiction as a whole and in particular how to approach this vulnerable subset of the population.

Repetitive transcranial magnetic stimulation in treatment-seeking subjects with cocaine use disorder: A randomized, double-blind, sham-controlled trial

BACKGROUND

Cocaine use disorder (CUD) is a chronic and relapsing brain disorder with no approved treatments. Repetitive transcranial magnetic stimulation (rTMS) has shown promising results in open label and single-blind studies, reducing cocaine craving and consumption. Although, large randomized, double-blind, controlled trials are still missing.

OBJECTIVE

This multi-center, randomized, double-blind, sham-controlled study was designed to evaluate the safety and efficacy of multiple sessions of active rTMS compared to sham stimulation in patients with CUD.

METHODS

rTMS (15 Hz, 2 daily sessions for 5 days/week,for a total of 20 stimulation sessions) was delivered over the left DLPFC for two weeks of continuous treatment followed by 12 weeks of maintenance (1 day/week, twice a day), in a double-blind, randomized sham-controlled design. Our primary outcomes included self-reported cue-induced craving and cocaine consumption, as measured by percentage of negative urine tests. Our secondary outcomes included: 1) changes in depressive symptoms; 2) changes in cocaine withdrawal symptoms; and 3) changes in self-reported days of cocaine use.

RESULTS

Forty-two outpatients with CUD were enrolled in the active rTMS group and 38 patients in the sham group. We observed a significant decrease in self-reported cue-induced cocaine craving and consumption in both the active rTMS and sham, whereas no main effect of treatment was found. However, the active rTMS group showed greater changes in depressive symptoms. The improvement on depressive symptomatology was particularly marked among patients receiving a total number of rTMS sessions greater than 40 and those reporting more severe depressive symptoms at baseline.

CONCLUSIONS

A significant improvement of CUD symptoms during active rTMS treatment was observed. However, we did not observe significant differences in cocaine craving and consumption between treatment groups, highlighting the complexity of factors contributing to CUD maintenance. A significant improvement in depressive symptoms was observed in favour of the active group. Clinical trial registration details:clinicaltrials.govidentifierNCT03333460.

Mini-review: When neurostimulation joins cognitive-behavioral therapy. On the need of combining evidence-based treatments for addiction disorders

Substance and behavioral addiction is a global health problem related to cognitive functioning and emotional responses like top-down control and craving. The present review discusses the role of non-invasive brain stimulation (NIBS) and cognitive-behavioral therapy (CBT) as evidence-based treatments for addiction disorders. The discussion spans between several evidence for both therapies, also considering the difference and heterogeneity among clinical protocols. Nowadays, literature is consistent in indicating the neurostimulation of the prefrontal cortex as effective for different kinds of addiction, corroborating the evidence that they rely on a common network in the brain. Likewise, within the CBT studies it is possible to observe a wide range of interventions that are overall effective in regulating the executive functions associated with addiction disorders. Nevertheless, the integration of NIBS and CBT in addictions has been scarcely considered in literature so far. For this reason, the present article is meant to foster empirical research in this field by highlighting the findings supporting these evidence-based interventions, both as stand-alone and integrated treatments. To this aim, psychological and neurophysiological mechanisms of NIBS and CBT in addictions are reviewed, and the rationale of their integration discussed. In particular, as evidence suggest these treatments affect top-down and bottom-up processes in different ways, with NIBS reducing craving and CBT boosting motivation and coping, we suggest their combination might better target the different components of addiction to promote abstinence.

Theta oscillations in rat infralimbic cortex are associated with the inhibition of cocaine seeking during extinction

Infralimbic cortical (IL) manipulations indicate that this region mediates extinction learning and suppresses cocaine seeking following cocaine self‐administration. However, little work has recorded IL activity during the inhibition of cocaine seeking due to the difficulty of determining precisely when cocaine‐seeking behaviour is inhibited within a cocaine‐seeking session. The present study used in vivo electrophysiology to examine IL activity across extinction as well as during cocaine self‐administration and reinstatement. Sprague–Dawley rats underwent 6‐h access cocaine self‐administration in which the response lever was available during discrete signalled trials, a procedure which allowed for the comparison between epochs of cocaine seeking versus the inhibition thereof. Subsequently, rats underwent extinction and cocaine‐primed reinstatement using the same procedure. Results indicate that theta rhythms (4–10 Hz) dominated IL local‐field potential (LFP) activity during all experimental stages. During extinction, theta power fluctuated significantly surrounding the lever press and was lower when rats engaged in cocaine seeking versus when they withheld from doing so. These patterns of oscillatory activity differed from self‐administration and reinstatement stages. Single‐unit analyses indicate heterogeneity of IL unit responses, supporting the idea that multiple neuronal subpopulations exist within the IL and promote the expression of different and even opposing cocaine‐seeking behaviours. Together, these results are consistent with the idea that aggregate synaptic and single‐unit activity in the IL represent the engagement of the IL in action monitoring to promote adaptive behaviour in accordance with task contingencies and reveal critical insights into the relationship between IL activity and the inhibition of cocaine seeking.

Role of maintenance treatment on long-term efficacy of bilateral iTBS of the prefrontal cortex in treatment-seeking cocaine addicts: A retrospective analysis

CUD, like other addictions, is a chronic disease characterized by a high rate of relapse and drop-out (DO) from medical and behavioral treatment programs, which is positively correlated with relapse. Repetitive transcranial Magnetic Stimulation (rTMS) protocols have shown therapeutic potential in addiction in the short term, but only a few studies have explored their long-term efficacy, so far. This study explores the long-term outcome of bilateral intermittent theta-burst stimulation (iTBS) of the prefrontal cortex (PFC) in cocaine use disorder (CUD) and the possible influence of maintenance treatment in improving abstinence and decreasing DO rates. Eighty-nine treatment-seeking CUD patients were exposed to 20 sessions of iTBS. At the end of the treatment 61 (81%) abstinent patients underwent a 12 months follow-up. Among these, 27 patients chose to follow a maintenance treatment (M), whereas 34 patients chose not to adhere to a maintenance treatment (NM). Overall, among patients reaching the 12 months follow-up endpoint, 69.7% were still abstinent and 30.3% relapsed. In NM-patients the DO rate was significantly higher than in M-ones (58.82 vs. 29.63%). The present observations show the long-term therapeutic effect of bilateral PFC iTBS to decrease cocaine consumption. Moreover, they underline the importance to perform a maintenance protocol to consolidate abstinence and decrease DO rates over time.

Transcranial Magnetic Stimulation for the Treatment of Cocaine Addiction: A Systematic Review

Long-term cocaine use is associated with cognitive deficits and neuro-psychiatric pathologies. Repetitive transcranial magnetic stimulation (rTMS) is an emerging therapeutic strategy relating to changes in brain activity. It stimulates the prefrontal cortex and is involved in inhibitory cognitive control, decision making and care. This systematic review aims to evaluate and synthesize the evidence on the safety, effectiveness, and cost-effectiveness of rTMS for the treatment of cocaine addiction. A systematic review of the literature was carried out. The following electronic databases were consulted from inception to October 2020: MEDLINE, Embase, CINAHL, PsycINFO, Cochrane Central Register of Controlled Trials and Web of Science. Randomised controlled trials, non-randomised controlled trials and case-series and full economic evaluations were included. Twelve studies were included. No identified study reported data on cost-effectiveness. Significant results of the efficacy of TMS have been observed in terms of the reduction of craving to consume and the number of doses consumed. No serious adverse effects have been observed. Despite the low quality of the studies, the first results were observed in terms of reduction of cocaine use and craving. In any case, this effect is considered moderate. Studies with larger sample sizes and longer follow-ups are required.

A randomised, double-blind, sham-controlled study of left prefrontal cortex 15 Hz repetitive transcranial magnetic stimulation in cocaine consumption and craving

Background

Cocaine use disorder (CUD) is a global health issue with no effective treatment. Repetitive Transcranial Magnetic Stimulation (rTMS) is a recently proposed therapy for CUD.

Methods

We conducted a single-center, randomised, sham-controlled, blinded, parallel-group research with patients randomly allocated to rTMS (15 Hz) or Sham group (1:1) using a computerised block randomisation process. We enrolled 62 of 81 CUD patients in two years. Patients were followed for eight weeks after receiving 15 15 Hz rTMS/sham sessions over the left dorsolateral prefrontal cortex (DLPFC) during the first three weeks of the study. We targeted the DLFPC following the 5 cm method. Cocaine lapses in twice a week urine tests were the primary outcome. The secondary outcomes were craving severity, cocaine use pattern, and psychometric assessments.

Findings

We randomly allocated patients to either an active rTMS group (32 subjects) or a sham treatment group (30 subjects). Thirteen (42%) and twelve (43.3%) of the subjects in rTMS and sham groups, respectively, completed the full trial regimen, displaying a high dropout rate. Ten/30 (33%) of rTMS-treated patients tested negative for cocaine in urine, in contrast to 4/27 of placebo controls (p = 0.18, odd ratio 2.88, CI 0.9–10). The Kaplan-Meier survival curve did not state a significant change between the treated and sham groups in the time of cocaine urine negativisation (p = 0.20). However, the severity of cocaine-related cues mediated craving (VAS peak) was substantially decreased in the rTMS treated group (p<0.03) after treatment at T1, corresponding to the end of rTMS treatment. Furthermore, in the rTMS and sham groups, self-reported days of cocaine use decreased significantly (p<0.03). Finally, psychometric impulsivity parameters improved in rTMS-treated patients, while depression scales improved in both groups.

Conclusions

In CUD, rTMS could be a useful tool for lowering cocaine craving and consumption.

Trial registration

The study number on clinicalTrials.gov is NCT03607591.

Repetitive transcranial magnetic stimulation as a potential treatment approach for cannabis use disorder

The expanding legalization of cannabis across the United States is associated with increases in cannabis use, and accordingly, an increase in the number and severity of individuals with cannabis use disorder (CUD). The lack of FDA-approved pharmacotherapies and modest efficacy of psychotherapeutic interventions means that many of those who seek treatment for CUD relapse within the first few months. Consequently, there is a pressing need for innovative, evidence-based treatment development for CUD. Preliminary evidence suggests that repetitive transcranial magnetic stimulation (rTMS) may be a novel, non-invasive therapeutic neuromodulation tool for the treatment of a variety of substance use disorders (SUDs), including recently receiving FDA clearance (August 2020) for use as a smoking cessation aid in tobacco cigarette smokers. However, the potential of rTMS for CUD has not yet been reviewed. This paper provides a primer on therapeutic neuromodulation techniques for SUDs, with a particular focus on reviewing the current status of rTMS research in people who use cannabis. Lastly, future directions are proposed for rTMS treatment development in CUD, with suggestions for study design parameters and clinical endpoints based on current gold-standard practices for therapeutic neuromodulation research.

Can pharmacotherapy improve treatment outcomes in people with co-occurring major depressive and cocaine use disorders?

Introduction: Major depressive disorder (MDD) and cocaine use disorder (CUD) are prevalent and frequently co-occur. When co-occurring, the presence of one disorder typically negatively impacts the prognosis for the other. Given the clinical relevance, we sought to examine pharmacotherapies for co-occurring CUD and MDD. While multiple treatment options have been examined in the treatment of each condition individually, studies exploring pharmacological options for their comorbidity are fewer and not conclusive.Areas Covered: For this review, the authors searched the literature in PubMed using clinical query options for therapies and keywords relating to each condition. Then, they described potentially promising pharmacologic therapeutic options based on shared mechanisms between the two conditions and/or results from individual clinical trials conducted to date.Expert opinion: Medications like stimulants, dopamine (D3) receptors partial agonists or antagonists, antagonists of kappa opioid receptors, topiramate, and ketamine could be promising as there is significant overlap relating to reward deficiency models, antireward pathways, and altered glutamatergic systems. However, the available clinical literature on any one of these types of agents is mixed. Additionally, for some agents there is possible concern related to abuse potential (e.g. ketamine and stimulants).

A double-blind sham-controlled phase 1 clinical trial of tDCS of the dorsolateral prefrontal cortex in cocaine inpatients: Craving, sleepiness, and contemplation to change

Impaired inhibitory control accompanied by enhanced salience attributed to drug-related cues, both associated with function of the dorsolateral prefrontal cortex (dlPFC), are hallmarks of drug addiction, contributing to worse symptomatology including craving. dlPFC modulation with transcranial direct current stimulation (tDCS) previously showed craving reduction in inpatients with cocaine use disorder (CUD). Our study aimed at assessing feasibility of a longer tDCS protocol in CUD (15 versus the common five/10 sessions) and replicability of previous results. In a randomized double-blind sham-controlled protocol, 17 inpatients with CUD were assigned to either a real-tDCS (right anodal/left cathodal) or a sham-tDCS condition for 15 sessions. Following the previous report, primary outcome measures were self-reported craving, anxiety, depression, and quality of life. Secondary measures included sleepiness, readiness to change drug use, and affect. We also assessed cognitive function including impulsivity. An 88% retention rate demonstrated feasibility. Partially supporting the previous results, there was a trend for self-reported craving to decrease in the real-tDCS group more than the sham-group, an effect that would reach significance with 15 subjects per group. Quality of life and impulsivity improved over time in treatment in both groups. Daytime sleepiness and readiness to change drug use showed significant Group × Time interactions whereby improvements were noted only in the real-tDCS group. One-month follow-up suggested transient effects of tDCS on sleepiness and craving. These preliminary results suggest the need for including more subjects to show a unique effect of real-tDCS on craving and examine the duration of this effect. After replication in larger sample sizes, increased vigilance and motivation to change drug use in the real-tDCS group may suggest fortification of dlPFC-supported executive functions.

Transcranial Magnetic Stimulation: A review about its efficacy in the treatment of alcohol, tobacco and cocaine addiction

Substance Use Disorder (SUD) is a chronic and relapsing disease characterized by craving, loss of control, tolerance and physical dependence. At present, the combination of pharmacotherapy and psychosocial intervention is the most effective management strategy in preventing relapse to reduce dropout rates and promote abstinence in SUD patients. However, only few effective medications are available. Transcranial Magnetic Stimulation (TMS) is a non-invasive brain stimulation technique that modulates the cellular activity of the cerebral cortex through a magnetic pulse applied on selected brain areas. Recently, the efficacy of TMS has been investigated in various categories of SUD patients. The present review analyzes the application of repetitive TMS in patients with alcohol, tobacco, and cocaine use disorder. Although the number of clinical studies is still limited, repetitive TMS yields encouraging results in these patients, suggesting a possible role of TMS in the treatment of SUD.

Clinical and Functional Connectivity Outcomes of 5-Hz Repetitive Transcranial Magnetic Stimulation as an Add-on Treatment in Cocaine Use Disorder: A Double-Blind Randomized Controlled Trial

BACKGROUND

Cocaine use disorder (CUD) is a global condition lacking effective treatment. Repetitive transcranial magnetic stimulation (rTMS) may reduce craving and frequency of cocaine use, but little is known about its efficacy and neural effects. We sought to elucidate short- and long-term clinical benefits of 5-Hz rTMS as an add-on to standard treatment in patients with CUD and discern underlying functional connectivity effects using magnetic resonance imaging.

METHODS

A total of 44 patients with CUD were randomly assigned to complete the 2-week double-blind randomized controlled trial (acute phase) (sham [n = 20, 2 female] and active [n = 24, 4 female]), in which they received two daily sessions of rTMS on the left dorsolateral prefrontal cortex (PFC). Subsequently, 20 patients with CUD continued to an open-label maintenance phase for 6 months (two weekly sessions for up to 6 mo).

RESULTS

rTMS plus standard treatment for 2 weeks significantly reduced craving (baseline: 3.9 ± 3.6; 2 weeks: 1.5 ± 2.4, p = .013, d = 0.77) and impulsivity (baseline: 64.8 ± 16.8; 2 weeks: 53.1 ± 17.4, p = .011, d = 0.79) in the active group. We also found increased functional connectivity between the left dorsolateral PFC and ventromedial PFC and between the ventromedial PFC and right angular gyrus. Clinical and functional connectivity effects were maintained for 3 months, but they dissipated by 6 months. We did not observe reduction in positive results for cocaine in urine; however, self-reported frequency and grams consumed for 6 months were reduced.

CONCLUSIONS

With this randomized controlled trial, we show that 5-Hz rTMS has potential promise as an adjunctive treatment for CUD and merits further research.

The Role of Gut Microbiota in the High-Risk Construct of Severe Mental Disorders: A Mini Review

Severe mental disorders (SMD) are highly prevalent psychiatric conditions exerting an enormous toll on society. Therefore, prevention of SMD has received enormous attention in the last two decades. Preventative approaches are based on the knowledge and detailed characterization of the developmental stages of SMD and on risk prediction. One relevant biological component, so far neglected in high risk research, is microbiota. The human microbiota consists in the ensemble of microbes, including viruses, bacteria, and eukaryotes, that inhabit several ecological niches of the organism. Due to its demonstrated role in modulating illness and health, as well in influencing behavior, much interest has focused on the characterization of the microbiota inhabiting the gut. Several studies in animal models have shown the early modifications in the gut microbiota might impact on neurodevelopment and the onset of deficits in social behavior corresponding to distinct neurosignaling alterations. However, despite this evidence, only one study investigated the effect of altered microbiome and risk of developing mental disorders in humans, showing that individuals at risk for SMD had significantly different global microbiome composition than healthy controls. We then offer a developmental perspective and provided mechanistic insights on how changes in the microbiota could influence the risk of SMD. We suggest that the analysis of microbiota should be included in the comprehensive assessment generally performed in populations at high risk for SMD as it can inform predictive models and ultimately preventative strategies.

A Retrospective Comparative Study in Patients With Cocaine Use Disorder Comorbid With Attention Deficit Hyperactivity Disorder Undergoing an rTMS Protocol Treatment

Background: Adult attention-deficit/hyperactivity disorder (ADHD) is associated with high comorbidity with other psychiatric diseases, including cocaine use disorder (CocUD). Given the common fronto-striatal dysfunction, ADHD patients often use cocaine as self-medication for ameliorating symptoms by increasing striatal dopamine release. Yet, comorbidity with ADHD is related to poor treatment outcomes. CocUD has been treated with transcranial magnetic stimulation (TMS), but no studies investigated the outcomes in patients comorbid with ADHD. Methods: Twenty-two ADHD/CocUD and 208 CocUD-only participants received a high-frequency (15 Hz) rTMS treatment stimulating the left-DLPFC. We investigated whether both groups of patients shared similar demographic and clinical characteristics at baseline. Then, we monitored the effect of treatment testing for potential differences between groups. Results: At baseline demographic, toxicology and clinical features were not different between the two groups except for global severity index (GSI from SCL-90): patients of ADHD/CocUD group reported higher general symptomatology compared to the CocUD-only group. Concerning the effect of treatment, both groups significantly improved over time regarding cocaine use, craving, and other negative affect symptoms. No differences were observed between groups. Conclusions: To our knowledge, this is the first study comparing the demographic characterization and rTMS clinical improvements of patients with a dual diagnosis of ADHD and CocUD against CocUD-only patients. Cocaine use and common self-reported withdrawal/abstinence symptoms appear to benefit from rTMS treatment with no differences between groups. Future studies are needed to further investigate these preliminary results.

The hypodopaminergic state ten years after: transcranial magnetic stimulation as a tool to test the dopamine hypothesis of drug addiction

An altered dopamine transmission has been described for different types of addiction for a long time. Preclinical and clinical evidence support the hypodopaminergic hypothesis and underpin the need to increase dopamine transmission to obtain therapeutic benefit. Repetitive transcranial magnetic stimulation (rTMS) of prefrontal cortex shows efficacy in treating some forms of addiction. Recent imaging studies confirmed that the therapeutic effect of rTMS is correlated with an enhancement of dopamine transmission. Novel targets for rTMS are under evaluation to increase its effectiveness in treating addiction, and research is ongoing to find the optimal protocol to boost dopaminergic transmission in the addicted brain. TMS can thus be considered a useful tool to test the dopamine hypothesis of drug addiction and instrumental in the search for addiction therapeutics.

Non-invasive Brain Stimulation for Gambling Disorder: A Systematic Review

Background: Gambling disorder (GD) is the most common behavioral addiction and shares pathophysiological and clinical features with substance use disorders (SUDs). Effective therapeutic interventions for GD are lacking. Non-invasive brain stimulation (NIBS) may represent a promising treatment option for GD.

Objective: This systematic review aimed to provide a comprehensive and structured overview of studies applying NIBS techniques to GD and problem gambling.

Methods: A literature search using Pubmed, Web of Science, and Science Direct was conducted from databases inception to December 19, 2019, for studies assessing the effects of repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (t-DCS) on subjects with GD or problem gambling. Studies using NIBS techniques on healthy subjects and those without therapeutic goals but only aiming to assess basic neurophysiology measures were excluded.

Results: A total of 269 articles were title and abstract screened, 13 full texts were assessed, and 11 were included, of which six were controlled and five were uncontrolled. Most studies showed a reduction of gambling behavior, craving for gambling, and gambling-related symptoms. NIBS effects on psychiatric symptoms were less consistent. A decrease of the behavioral activation related to gambling was also reported. Some studies reported modulation of behavioral measures (i.e., impulsivity, cognitive and attentional control, decision making, cognitive flexibility). Studies were not consistent in terms of NIBS protocol, site of stimulation, clinical and surrogate outcome measures, and duration of treatment and follow-up. Sample size was small in most studies.

Conclusions: The clinical and methodological heterogeneity of the included studies prevented us from drawing any firm conclusion on the efficacy of NIBS interventions for GD. Further methodologically sound, robust, and well-powered studies are needed.

Cocaine-induced ischemia in prefrontal cortex is associated with escalation of cocaine intake in rodents

Cocaine-induced vasoconstriction reduces blood flow, which can jeopardize neuronal function and in the prefrontal cortex (PFC) it may contribute to compulsive cocaine intake. Here, we used integrated optical imaging in a rat self-administration and a mouse noncontingent model, to investigate whether changes in the cerebrovascular system in the PFC contribute to cocaine self-administration, and whether they recover with detoxification. In both animal models, cocaine induced severe vasoconstriction and marked reductions in cerebral blood flow (CBF) in the PFC, which were exacerbated with chronic exposure and with escalation of cocaine intake. Though there was a significant proliferation of blood vessels in areas of vasoconstriction (angiogenesis), CBF remained reduced even after 1 month of detoxification. Treatment with Nifedipine (Ca²⁺ antagonist and vasodilator) prevented cocaine-induced CBF decreases and neuronal Ca²⁺ changes in the PFC, and decreased cocaine intake and blocked reinstatement of drug seeking. These findings provide support for the hypothesis that cocaine-induced CBF reductions lead to neuronal deficits that contribute to hypofrontality and to compulsive-like cocaine intake in addiction, and document that these deficits persist at least one month after detoxification. Our preliminary data showed that nifedipine might be beneficial in preventing cocaine-induced vascular toxicity and in reducing cocaine intake and preventing relapse.

Sleep quality improves during treatment with repetitive transcranial magnetic stimulation (rTMS) in patients with cocaine use disorder: a retrospective observational study

BACKGROUND

Sleep disturbance is a prominent and common complaint in people with cocaine use disorder (CUD), either during intake or withdrawal. Repetitive transcranial magnetic stimulation (rTMS) has shown promise as a treatment for CUD. Thus, we evaluated the relationship between self-perceived sleep quality and cocaine use pattern variables in outpatients with CUD undergoing an rTMS protocol targeted at the left dorsolateral prefrontal cortex.

METHODS

This is a retrospective observational study including 87 patients diagnosed with CUD according to the DSM-5 criteria. Scores in Pittsburgh Sleep Quality Index (PSQI), Cocaine Craving Questionnaire (CCQ), Beck Depression Inventory-II (BDI-II), Self-rating Anxiety Scale (SAS), and Symptoms checklist 90-Revised (outcome used: Global Severity Index, GSI) were recorded at baseline, and after 5, 30, 60, and 90 days of rTMS treatment. Cocaine use was assessed by self-report and regular urine screens.

RESULTS

Sleep disturbances (PSQI scores > 5) were common in patients at baseline (mean ± SD; PSQI score baseline: 9.24 ± 3.89; PSQI > 5 in 88.5% of patients). PSQI scores significantly improved after rTMS treatment (PSQI score Day 90: 6.12 ± 3.32). Significant and consistent improvements were also seen in craving and in negative-affect symptoms compared to baseline. Considering the lack of a control group, in order to help the conceptualization of the outcomes, we compared the results to a wait-list group (n = 10). No significant improvements were observed in the wait-list group in any of the outcome measures.

CONCLUSIONS

The present findings support the therapeutic role of rTMS interventions for reducing cocaine use and accompanying symptoms such as sleep disturbance and negative-affect symptoms.

TRIAL REGISTRATION

ClinicalTrials.gov.NCT03733821.

rTMS-Induced Changes in Glutamatergic and Dopaminergic Systems: Relevance to Cocaine and Methamphetamine Use Disorders

Cocaine use disorder and methamphetamine use disorder are chronic, relapsing disorders with no US Food and Drug Administration-approved interventions. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation tool that has been increasingly investigated as a possible therapeutic intervention for substance use disorders. rTMS may have the ability to induce beneficial neuroplasticity in abnormal circuits and networks in individuals with addiction. The aim of this review is to highlight the rationale and potential for rTMS to treat cocaine and methamphetamine dependence: we synthesize the outcomes of studies in healthy humans and animal models to identify and understand the neurobiological mechanisms of rTMS that seem most involved in addiction, focusing on the dopaminergic and glutamatergic systems. rTMS-induced changes to neurotransmitter systems include alterations to striatal dopamine release and metabolite levels, as well as to glutamate transporter and receptor expression, which may be relevant for ameliorating the aberrant plasticity observed in individuals with substance use disorders. We also discuss the clinical studies that have used rTMS in humans with cocaine and methamphetamine use disorders. Many such studies suggest changes in network connectivity following acute rTMS, which may underpin reduced craving following chronic rTMS. We suggest several possible future directions for research relating to the therapeutic potential of rTMS in addiction that would help fill current gaps in the literature. Such research would apply rTMS to animal models of addiction, developing a translational pipeline that would guide evidence-based rTMS treatment of cocaine and methamphetamine use disorder.

Long-Term Outcome of Repetitive Transcranial Magnetic Stimulation in a Large Cohort of Patients With Cocaine-Use Disorder: An Observational Study

Background: Cocaine is a psychostimulant drug used as performance enhancer throughout history. The prolonged use of cocaine is associated with addiction and a broad range of cognitive deficits. Currently, there are no medications proven to be effective for cocaine-use disorder (CocUD). Previous preliminary clinical work suggests some benefit from repetitive transcranial magnetic stimulation (rTMS) stimulating the prefrontal cortex (PFC), involved in inhibitory cognitive control, decision-making and attention. All published studies to date have been limited by small sample sizes and short follow-up times. Methods: This is a retrospective observational study of 284 outpatients (of whom 268 were men) meeting DSM-5 criteria for CocUD. At treatment entry, most were using cocaine every day or several times per week. All patients underwent 3 months of rTMS and were followed for up to 2 years, 8 months. Self-report, reports by family or significant others and regular urine screens were used to assess drug use. Results: Median time to the first lapse (resumption of cocaine use) since the beginning of treatment was 91 days. For most patients, TMS was re-administered weekly, then monthly, throughout follow-up. The decrease in frequency of rTMS sessions was not accompanied by an increase in lapses to cocaine use. Mean frequency of cocaine use was <1·0 day/month (median 0), while serious rTMS-related adverse events were infrequent, consistent with published reports from smaller studies. Conclusions: This is the first follow-up study to show that rTMS treatment is accompanied by long-lasting reductions in cocaine use in a large cohort.

Stabilization Beyond Mood: Stabilizing Patients With Bipolar Disorder in the Various Phases of Life

BACKGROUND

There are different ways to define stabilization and currently, the main standpoint regards it as no-depression/no-mania. Furthermore, each person is physiologically different from childhood to adulthood, and in old age, thus the meaning of stabilization should take into account both growth and maturity. We aimed to review systematically studies focusing on mood stabilization in all phases of bipolar disorder (BD) and across all life phases, including pregnancy and the perinatal period, which is still a different phase in women's life cycles.

METHODS

We carried out a PubMed search focusing on studies of bipolar disorder treated with drugs and aimed at stabilization with the following search strategy stabiliz*[ti] OR stabilis*[ti] OR stable[ti] OR stability[ti]) AND mood[ti] AND bipolar. In conducting our review, we followed the PRISMA statement. Agreement on inclusion was reached by consensus of all authors through a Delphi rounds procedure.

RESULTS

The above search strategy produced 509 records on January 25, 2020. Of them, 58 fitted our inclusion criteria and were discussed. The eligible studies spanned from September 1983 to July 6, 2019.

CONCLUSIONS

No clear-cut indications could be drawn due to a number of limitations involving sample inconsistency and different methods of assessing mood stabilization. The evidence collected so far does not allow recommended treatments for Adolescents, pregnant or perinatal women, and aged patients. However, adults, not within these groups, better focused upon. For their manic/mixed phases, second generation antipsychotic drugs may be useful in the short-to-medium run, alone or combined with mood stabilizers (MSs). However, MSs, and especially lithium, continue to be pivotal in chronic treatment. Bipolar depression should rely on MSs, but an antidepressant may be added on and can prove to be helpful. However, there are concerns with the tendency of antidepressants to induce the opposite polarity or mood instability, rendering the need for concurrent MS prescription mandatory.

Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS): An update (2014-2018)

A group of European experts reappraised the guidelines on the therapeutic efficacy of repetitive transcranial magnetic stimulation (rTMS) previously published in 2014 [Lefaucheur et al., Clin Neurophysiol 2014;125:2150-206]. These updated recommendations take into account all rTMS publications, including data prior to 2014, as well as currently reviewed literature until the end of 2018. Level A evidence (definite efficacy) was reached for: high-frequency (HF) rTMS of the primary motor cortex (M1) contralateral to the painful side for neuropathic pain; HF-rTMS of the left dorsolateral prefrontal cortex (DLPFC) using a figure-of-8 or a H1-coil for depression; low-frequency (LF) rTMS of contralesional M1 for hand motor recovery in the post-acute stage of stroke. Level B evidence (probable efficacy) was reached for: HF-rTMS of the left M1 or DLPFC for improving quality of life or pain, respectively, in fibromyalgia; HF-rTMS of bilateral M1 regions or the left DLPFC for improving motor impairment or depression, respectively, in Parkinson's disease; HF-rTMS of ipsilesional M1 for promoting motor recovery at the post-acute stage of stroke; intermittent theta burst stimulation targeted to the leg motor cortex for lower limb spasticity in multiple sclerosis; HF-rTMS of the right DLPFC in posttraumatic stress disorder; LF-rTMS of the right inferior frontal gyrus in chronic post-stroke non-fluent aphasia; LF-rTMS of the right DLPFC in depression; and bihemispheric stimulation of the DLPFC combining right-sided LF-rTMS (or continuous theta burst stimulation) and left-sided HF-rTMS (or intermittent theta burst stimulation) in depression. Level A/B evidence is not reached concerning efficacy of rTMS in any other condition. The current recommendations are based on the differences reached in therapeutic efficacy of real vs. sham rTMS protocols, replicated in a sufficient number of independent studies. This does not mean that the benefit produced by rTMS inevitably reaches a level of clinical relevance.

Bouncing back: Brain rehabilitation amid opioid and stimulant epidemics

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Frontoparietal event related potentials predict/track recovery.

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Frontostriatal functional magnetic resonance imaging signals predict/track recovery.

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Transcranial magnetic left prefrontal stimulation reduces craving and drug use.

Recent methamphetamine and opioid use epidemics are a major public health concern. Chronic stimulant and opioid use are characterized by significant psychosocial, physical and mental health costs, repeated relapse, and heightened risk of early death. Neuroimaging research highlights deficits in brain processes and circuitry that are linked to responsivity to drug cues over natural rewards as well as suboptimal goal-directed decision-making. Despite the need for interventions, little is known about (1) how the brain changes with prolonged abstinence or as a function of various treatments; and (2) how symptoms change as a result of neuromodulation. This review focuses on the question: What do we know about changes in brain function during recovery from opioids and stimulants such as methamphetamine and cocaine? We provide a detailed overview and critique of published research employing a wide array of neuroimaging methods – functional and structural magnetic resonance imaging, electroencephalography, event-related potentials, diffusion tensor imaging, and multiple brain stimulation technologies along with neurofeedback – to track or induce changes in drug craving, abstinence, and treatment success in stimulant and opioid users. Despite the surge of methamphetamine and opioid use in recent years, most of the research on neuroimaging techniques for recovery focuses on cocaine use. This review highlights two main findings: (1) interventions can lead to improvements in brain function, particularly in frontal regions implicated in goal-directed behavior and cognitive control, paired with reduced drug urges/craving; and (2) the targeting of striatal mechanisms implicated in drug reward may not be as cost-effective as prefrontal mechanisms, given that deep brain stimulation methods require surgery and months of intervention to produce effects. Overall, more studies are needed to replicate and confirm findings, particularly for individuals with opioid and methamphetamine use disorders.

Excessive bodybuilding as pathology? A first neurophysiological classification

Objectives: Excessive bodybuilding as a pathological syndrome has been classified based on two different theories: bodybuilding as dependency or as muscle dysmorphic disorder (MDD). This study is a first attempt to find psychophysiological data supporting one of these classifications.Methods: Twenty-four participants (bodybuilders vs healthy controls) were presented with pictures of bodies, exercise equipment or general reward stimuli in a control or experimental condition, and were measured with functional near-infrared spectroscopy (fNIRS). Higher activation in the dorsolateral prefrontal cortex (DLPFC) and the orbitofrontal cortex (OFC) while watching bodies and training equipment in the experimental condition (muscular bodies and bodybuilding-typical equipment) would be an indicator for the addiction theory. Higher activation in motion-related areas would be an indicator for the MDD theory.Results: We found no task-related differences between the groups in the DLPFC and OFC, but a significantly higher activation in bodybuilders in the primary somatosensory cortex (PSC) and left-hemispheric supplementary motor area (SMA) while watching body pictures (across conditions) as compared to the control group.Conclusions: These neurophysiological results could be interpreted as a first evidence for the MDD theory of excessive bodybuilding.

The Neuroscience of Drug Reward and Addiction

Drug consumption is driven by a drug's pharmacological effects, which are experienced as rewarding, and is influenced by genetic, developmental, and psychosocial factors that mediate drug accessibility, norms, and social support systems or lack thereof. The reinforcing effects of drugs mostly depend on dopamine signaling in the nucleus accumbens, and chronic drug exposure triggers glutamatergic-mediated neuroadaptations in dopamine striato-thalamo-cortical (predominantly in prefrontal cortical regions including orbitofrontal cortex and anterior cingulate cortex) and limbic pathways (amygdala and hippocampus) that, in vulnerable individuals, can result in addiction. In parallel, changes in the extended amygdala result in negative emotional states that perpetuate drug taking as an attempt to temporarily alleviate them. Counterintuitively, in the addicted person, the actual drug consumption is associated with an attenuated dopamine increase in brain reward regions, which might contribute to drug-taking behavior to compensate for the difference between the magnitude of the expected reward triggered by the conditioning to drug cues and the actual experience of it. Combined, these effects result in an enhanced motivation to "seek the drug" (energized by dopamine increases triggered by drug cues) and an impaired prefrontal top-down self-regulation that favors compulsive drug-taking against the backdrop of negative emotionality and an enhanced interoceptive awareness of "drug hunger." Treatment interventions intended to reverse these neuroadaptations show promise as therapeutic approaches for addiction.

Transcranial electrical and magnetic stimulation (tES and TMS) for addiction medicine: A consensus paper on the present state of the science and the road ahead

There is growing interest in non-invasive brain stimulation (NIBS) as a novel treatment option for substance-use disorders (SUDs). Recent momentum stems from a foundation of preclinical neuroscience demonstrating links between neural circuits and drug consuming behavior, as well as recent FDA-approval of NIBS treatments for mental health disorders that share overlapping pathology with SUDs. As with any emerging field, enthusiasm must be tempered by reason; lessons learned from the past should be prudently applied to future therapies. Here, an international ensemble of experts provides an overview of the state of transcranial-electrical (tES) and transcranial-magnetic (TMS) stimulation applied in SUDs. This consensus paper provides a systematic literature review on published data - emphasizing the heterogeneity of methods and outcome measures while suggesting strategies to help bridge knowledge gaps. The goal of this effort is to provide the community with guidelines for best practices in tES/TMS SUD research. We hope this will accelerate the speed at which the community translates basic neuroscience into advanced neuromodulation tools for clinical practice in addiction medicine.

Weight loss induced by deep transcranial magnetic stimulation in obesity: A randomized, double-blind, sham-controlled study

AIM

To test the hypothesis that deep transcranial magnetic stimulation (dTMS) reduces food craving and causes weight loss via neuromodulation.

MATERIALS AND METHODS

This pilot study was designed as a randomized, double-blind, sham-controlled study. A total of 33 obese people (nine men, 24 women, mean age 48.1 ± 10.6 years, body mass index [BMI] 36.9 ± 4.7 kg/m² ) were randomized and completed the study: 13 participants underwent a 5-week treatment with high-frequency (HF) dTMS (18 Hz; HF group), 10 were treated with low-frequency (LF) dTMS (1 Hz; LF group), and 10 were sham-treated (sham group). Food craving, and metabolic and neuro-endocrine variables were evaluated at baseline, after the 5-week treatment, and at follow-up visits (1 month, 6 months, 1 year after the end of treatment).

RESULTS

The mixed-model analysis for repeated measures showed a significant interaction of time and groups for body weight (P = 0.001) and BMI (P = 0.001), with a significant body weight (-7.83 ± 2.28 kg; P = 0.0009) and BMI (-2.83 ± 0.83, P = 0.0009) decrease in the HF versus the sham group. A decreasing trend in food craving in the HF versus the LF and sham groups (P = 0.073) was observed. A significant improvement of metabolic and physical activity variables was found (P < 0.05) in the HF group.

CONCLUSIONS

We demonstrated the safety and efficacy of dTMS, in addition to physical exercise and a hypocaloric diet, in reducing body weight for up to 1 year in obese people. We hypothesize that a possible mechanism of HF dTMS treatment is modulation of the dopaminergic pathway and stimulation of physical activity.

Intermittent Theta Burst Stimulation of the Prefrontal Cortex in Cocaine Use Disorder: A Pilot Study

Transcranial Magnetic Stimulation (TMS) is earning a role in the therapeutic arsenal of cocaine use disorder (CUD). A widespread and still growing number of studies have reported beneficial use of repeated TMS (rTMS) in reduction of craving, intake and cue-induced craving in cocaine addicts. In spite of these encouraging findings, many issues are still unresolved such as brain area to be stimulated, laterality of the effects, coil geometry and stimulation protocols/parameters. Intermittent theta burst stimulation (iTBS) is a more tolerable protocol administered at lower intensities and shorter intervals than conventional rTMS protocols. Yet, its effects on cocaine craving and length of abstinence in comparison with standard high frequency (10–15 Hz) protocols have never been evaluated so far. In the present paper, we describe the effect of the bilateral iTBS of the prefrontal cortex (PFC) in a population (n = 25) of treatment-seeking cocaine addicts, in an outpatient setting, and compare them with 15 Hz stimulation of the same brain area (n = 22). The results indicate that iTBS produces effects on cocaine consumption and cocaine craving virtually superimposable to the 15 Hz rTMS group. Both treatments had low numbers of dropouts and similar side-effects, safety and tolerability profiles. While larger studies are warranted to confirm these observations, iTBS appears to be a valid approach to be considered in treatment-seeking cocaine addicts, especially in light of its brief duration (3 min) vs. 15 Hz stimulation (15 min). The use of iTBS would allow increasing the number of patients treated per day with current rTMS devices, thus reducing patient discomfort and hopefully reducing drop-out rates without compromising clinical effectiveness.

Clinical Improvements in Comorbid Gambling/Cocaine Use Disorder (GD/CUD) Patients Undergoing Repetitive Transcranial Magnetic Stimulation (rTMS)

(1) Background: Pathological gambling behaviors may coexist with cocaine use disorder (CUD), underlying common pathogenic mechanisms. Repetitive transcranial magnetic stimulation (rTMS) has shown promise as a therapeutic intervention for CUD. In this case series, we evaluated the clinical effects of rTMS protocol stimulating the left dorsolateral prefrontal cortex (DLPFC) on the pattern of gambling and cocaine use. (2) Methods: Gambling severity, craving for cocaine, sleep, and other negative affect symptoms were recorded in seven patients with a diagnosis of gambling disorder (South Oaks Gambling Screen (SOGS) >5), in comorbidity with CUD, using the following scales: Gambling-Symptom Assessment Scale (G-SAS), Cocaine Craving Questionnaire (CCQ), Beck Depression Inventory-II (BDI-II), Self-rating Anxiety Scale (SAS), and Symptoms checklist-90 (SCL-90). The measures were assessed before the rTMS treatment and after 5, 30, and 60 days of treatment. Patterns of gambling and cocaine use were assessed by self-report and regular urine screens. (3) Results: Gambling severity at baseline ranged from mild to severe (mean ± Standard Error of the Mean (SEM), G-SAS score baseline: 24.42 ± 2.79). G-SAS scores significantly improved after treatment (G-SAS score Day 60: 2.66 ± 1.08). Compared to baseline, consistent improvements were significantly seen in craving for cocaine and in negative-affect symptoms. (4) Conclusions: The present findings provide unprecedent insights into the potential role of rTMS as a therapeutic intervention for reducing both gambling and cocaine use in patients with a dual diagnosis.

Rewiring the Addicted Brain: Circuits-Based Treatment for Addiction

The advent of the noninvasive brain stimulation (NIBS) technique has paved the way for neural circuit-based treatments for addiction. Recently, evidence from both preclinical and clinical studies has evaluated the use of transcranial magnetic stimulation (TMS) as a safe and cost-effective therapeutic tool for substance use disorders (SUDs). Indeed, repetitive TMS impacts on neural activity inducing short- and long-term effects involving neuroplasticity mechanisms locally within the target area of stimulation and the network level throughout the brain. Here, we provide an integrated view of evidence highlighting the mechanisms of TMS-induced effects on modulating the maladaptive brain circuitry of addiction. We then review the preclinical and clinical findings suggesting rTMS as an effective interventional tool for the treatment of SUDs.

Repetitive transcranial magnetic stimulation: Re-wiring the alcoholic human brain

Alcohol use disorders (AUDs) are one of the leading causes of mortality and morbidity worldwide. In spite of significant advances in understanding the neural underpinnings of AUDs, therapeutic options remain limited. Recent studies have highlighted the potential of repetitive transcranial magnetic stimulation (rTMS) as an innovative, safe, and cost-effective treatment for AUDs. Here, we summarize the fundamental principles of rTMS and its putative mechanisms of action via neurocircuitries related to alcohol addiction. We will also discuss advantages and limitations of rTMS, and argue that Hebbian plasticity and connectivity changes, as well as state-dependency, play a role in shaping some of the long-term effects of rTMS. Visual imaging studies will be linked to recent clinical pilot studies describing the effect of rTMS on alcohol craving and intake, pinpointing new advances, and highlighting conceptual gaps to be filled by future controlled studies.

rTMS Reduces Psychopathological Burden and Cocaine Consumption in Treatment-Seeking Subjects With Cocaine Use Disorder: An Open Label, Feasibility Study

Introduction: Cocaine use disorder (CUD) currently represents a notable public health concern, linked with significant disability, high chances of chronicity, and lack of effective pharmacological or psychological treatments. Repetitive transcranial magnetic stimulation (rTMS) is supposed to be a potential therapeutic option for addictive disorders. Aim of this study was to evaluate the feasibility of rTMS on (1) cocaine craving and consumption and (2) other comorbid psychiatric symptoms. Methods: Twenty treatment seeking CUD subjects underwent 2 weeks of intensive rTMS treatment (15Hz; 5 days/week, twice a day for a total of 20 stimulation sessions) of the left dorsolateral prefrontal cortex, followed by 2 weeks of maintenance treatment (15Hz, 1 day/week, twice a day). Sixteen patients completed the study. Patients were evaluated at baseline (T0), after 2 weeks of treatment (T1), and at the end of the study (T2; 4 weeks), with the following scales: Cocaine Selective Severity Assessment (CSSA), Zung Self-Rating Anxiety Scale, Beck Depression Inventory (BDI), Symptom Checklist-90 (SCL-90), and the Insomnia Severity Index. Results: After four weeks of rTMS treatment, 9 out of 16 subjects (56.25%) had a negative urinalysis test, with a significant conversion rate with respect to baseline (Z = -3.00; p = 0.003). Craving scores significantly improved only at T2 (p = 0.020). The overall psychopathological burden, as measured by the SCL-90 Global Severity Index (GSI), significantly decreased during the study period (Z = -2.689; p = 0.007), with a relevant improvement with regards to depressive symptoms, anhedonia, and anxiety. Subjects exhibiting lower baseline scores on the SCL-90 were more likely to be in the positive outcome group at the end of the study (Z = -3.334; p = 0.001). Discussion: Findings from this study are consistent with previous contributions on rTMS use in subjects with cocaine use disorder. We evidenced a specific action on some psychopathological areas and a consequent indirect effect in terms of relapse prevention and craving reduction. A double-blind, sham-controlled, neuro-navigated rTMS study design is needed, in order to confirm the potential benefits of this technique, opening new scenarios in substance use disorders treatment.

Lack of Effects of Extended Sessions of Transcranial Direct Current Stimulation (tDCS) Over Dorsolateral Prefrontal Cortex on Craving and Relapses in Crack-Cocaine Users

Background: Non-invasive brain stimulation such as transcranial direct current stimulation (tDCS) has been investigated as additional therapeutic tool for drug use disorder. In a previous study, we showed that five sessions of tDCS applied bilaterally over the dorsolateral prefrontal cortex (dlPFC) reduced craving to the use of crack-cocaine in inpatients from a specialized clinic. In the present study, we examine if an extended number of sessions of the same intervention would reduce craving even further and affect also relapses to crack-cocaine use.

Methods: A randomized, double-blind, sham-controlled, clinical trial with parallel arms was conducted (https://clinicaltrials.gov/ct2/show/NCT02091167). Crack-cocaine patients from two private and one public clinics for treatment of drug use disorder were randomly allocated to two groups: real tDCS (5 cm × 7 cm, 2 mA, for 20 min, cathodal over the left dlPFC and anodal over the right dlPFC, n = 19) and sham-tDCS (n = 16). Real or sham-tDCS was applied once a day, every other day, in a total of 10 sessions. Craving was monitored by a 5-item obsessive compulsive drinking scale once a week (one time before, three times during and once after brain stimulation) over about 5 weeks and relapse was monitored after their discharge from clinics for up to 60 days.

Results: Craving scores progressively decreased over five measurements in both sham- and real tDCS groups. Corrected Hedges’ within-group (initial and final) effect sizes of craving scores were of 0.77 for the sham-tDCS and of 0.97 for the real tDCS group. The between-groups effect size was of 0.34, in favor of the real tDCS group over sham-tDCS group. Relapse rates were high and quite similar between groups in the 30- and 60-days follow-up after discharge from the hospital.

Conclusion: Extended repetitive bilateral tDCS over the dlPFC had no add-on effects over regular treatment when considering craving and relapses to the crack-cocaine use in a sample of crack-cocaine patients with severe use disorder. Different tDCS montages targeting other cortical regions and perhaps additional extension of sessions need to be investigated to reach more efficiency in managing craving and relapses to crack-cocaine use.

Modulating Neural Circuits with Transcranial Magnetic Stimulation: Implications for Addiction Treatment Development

Although the last 50 years of clinical and preclinical research have demonstrated that addiction is a brain disease, we still have no neural circuit-based treatments for substance dependence or cue reactivity at large. Now, for the first time, it appears that a noninvasive brain stimulation technique known as transcranial magnetic stimulation (TMS), which is Food and Drug Administration approved to treat depression, may be the first tool available to fill this critical void in addiction treatment development. The goals of this review are to 1) introduce TMS as a tool to induce causal change in behavior, cortical excitability, and frontal-striatal activity; 2) describe repetitive TMS (rTMS) as an interventional tool; 3) provide an overview of the studies that have evaluated rTMS as a therapeutic tool for alcohol and drug use disorders; and 4) outline a conceptual framework for target selection when designing future rTMS clinical trials in substance use disorders. The manuscript concludes with some suggestions for methodological innovation, specifically with regard to combining rTMS with pharmacotherapy as well as cognitive behavioral training paradigms. We have attempted to create a comprehensive manuscript that provides the reader with a basic set of knowledge and an introduction to the primary experimental questions that will likely drive the field of TMS treatment development forward for the next several years.

Transcranial magnetic stimulation for the treatment of cocaine addiction: evidence to date

There is a common consensus in considering substance-use disorders (SUDs) a devastating chronic illness with social and psychological impact. Despite significant progress in understanding the neurobiology of SUDs, therapeutic advances have proceeded at a slower pace, in particular for cocaine-use disorder (CUD). Transcranial magnetic stimulation (TMS) is gaining support as a safe and cost-effective tool in the treatment of SUDs. In this review, we consider human studies that have investigated the efficacy of TMS in achieving therapeutic benefits in treating CUD. All studies conducted to date that have evaluated the therapeutic effect of TMS in CUD are included. We focus on the protocol of stimulation applied, emphasizing the neurophysiological effects of coils employed related to outcomes. Moreover, we examine the subjective and objective measurements used to assess the therapeutic effects along the timeline considered. The revision of scientific literatures underscores the therapeutic potential of TMS in treating CUD. However, the variability in stimulation protocols applied and the lack of methodological control do not allow us to draw firm conclusions, and further studies are warranted to examine the interaction between TMS patterns of stimulation relative to clinical outcomes in depth.

Can deep transcranial magnetic stimulation (DTMS) be used to treat substance use disorders (SUD)? A systematic review

BACKGROUND

Deep transcranial magnetic stimulation (DTMS) is a non-invasive method of stimulating widespread cortical areas and, presumably, deeper neural networks. The current study assessed the effects of DTMS in the treatment of substance use disorders (SUD) using a systematic review.

METHODS

Electronic literature search (PsycInfo, Medline until April 2017) identified k = 9 studies (k = 4 randomized-controlled trials, RCTs, with inactive sham and k = 5 open-label studies). DTMS was most commonly applied using high frequency/intensity (10-20 Hz/100-120% of the resting motor threshold, MT) protocols for 10-20 daily sessions in cases with alcohol, nicotine or cocaine use disorders. The outcome measures were craving and dependence (according to standardized scales) or consumption (frequency, abstinence or results of biological assays) at the end of the daily treatment phases and at the last follow-up.

RESULTS

Acute and longer-term (6-12 months) reductions in alcohol craving were observed after 20 sessions (20 Hz, 120% MT) relative to baseline in k = 4 open-label studies with comorbid SUD and major depressive disorder (MDD). In k = 2 RCTs without MDD, alcohol consumption acutely decreased after 10-12 sessions (10-20 Hz, 100-120% MT) relative to baseline or to sham. Alcohol craving was reduced only after higher frequency/intensity DTMS (20 Hz, 120% MT) relative to sham in k = 1 RCT. Nicotine consumption was reduced and abstinence was increased after 13 sessions (10 Hz, 120% MT) and at the 6-month follow-up relative to sham in k = 1 RCT. Cocaine craving was reduced after 12 sessions (15 Hz, 100% MT) and at the 2-month follow-up relative to baseline in k = 1 open-label study while consumption was reduced after 12 sessions (10 Hz, 100% MT) relative to baseline but not to sham in k = 1 RCT.

CONCLUSIONS

High-frequency DTMS may be effective at treating some SUD both acutely and in the longer-term. Large RCTs with inactive sham are required to determine the efficacy and the optimal stimulation parameters of DTMS for the treatment of SUD.

A review of brain stimulation methods to treat substance use disorders

BACKGROUND

Substance use disorders (SUDs) are a leading cause of disability worldwide. While several pharmacological and behavioral treatments for SUDs are available, these may not be effective for all patients. Recent studies using non-invasive neuromodulation techniques including Repetitive Transcranial Magnetic Stimulation (rTMS), Transcranial Direct Current Stimulation (tDCS), and Deep Brain Stimulation (DBS) have shown promise for SUD treatment.

OBJECTIVE

Multiple studies were evaluated investigating the therapeutic potential of non-invasive brain stimulation techniques in treatment of SUDs.

METHOD

Through literature searches (eg, PubMed, Google Scholar), 60 studies (2000-2017) were identified examining the effect of rTMS, tDCS, or DBS on cravings and consumption of SUDs, including tobacco, alcohol, cannabis, opioids, and stimulants.

RESULTS

rTMS and tDCS demonstrated decreases in drug craving and consumption, while early studies with DBS suggest similar results. Results are most encouraging when stimulation is targeted to the Dorsolateral Prefrontal Cortex (DLPFC).

CONCLUSIONS

Short-term treatment with rTMS and tDCS may have beneficial effects on drug craving and consumption. Future studies should focus on extending therapeutic benefits by increasing stimulation frequency and duration of treatment.

SCIENTIFIC SIGNIFICANCE

The utility of these methods in SUD treatment and prevention are unclear, and warrants further study using randomized, controlled designs. (Am J Addict 2018;27:71-91).

Neurostimulation techniques in the treatment of cocaine dependence: A review of the literature

OBJECTIVE

Cocaine use disorder is a very common condition that represents a substantial public health problem, and no effective pharmacological or psychological therapies have been identified to date. Urgent therapeutic alternatives are therefore needed such as neurostimulation techniques. The purpose of this review is to describe and discuss studies that have evaluated the safety and efficacy of these techniques for the treatment of cocaine 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 cocaine addiction were reviewed.

RESULTS

Most of these studies which are few in numbers and with limited sample sizes found that some of these neurostimulation techniques, particularly transcranial magnetic stimulation, and transcranial direct current stimulation are safe and potentially effective in the reduction of craving to cocaine. Although deep brain stimulation showed some good results in one patient, no conclusion can be drawn so far concerning the efficacy and safety of this approach.

CONCLUSION

Given the somewhat promising results of some of the studies, future controlled studies with larger samples, and optimal stimulus parameters should be designed to confirm the short- and long-term safety and efficacy of neurostimulation techniques to treat cocaine addiction.

Transcranial Magnetic Stimulation of Medial Prefrontal and Cingulate Cortices Reduces Cocaine Self-Administration: A Pilot Study

BACKGROUND

Previous studies have shown that repetitive transcranial magnetic stimulation (rTMS) to the dorsolateral prefrontal cortex may serve as a potential treatment for cocaine use disorder (CUD), which remains a public health problem that is refractory to treatment. The goal of this pilot study was to investigate the effect of rTMS on cocaine self-administration in the laboratory. In the self-administration sessions, CUD participants chose between cocaine and an alternative reinforcer (money) in order to directly measure cocaine-seeking behavior. The rTMS was delivered with the H7 coil, which provides stimulation to the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC). These brain regions were targeted based on previous imaging studies demonstrating alterations in their activation and connectivity in CUD.

METHODS

Volunteers with CUD were admitted to an inpatient unit for the entire study and assigned to one of three rTMS groups: high frequency (10 Hz), low frequency (1 Hz), and sham. Six participants were included in each group and the rTMS was delivered on weekdays for 3 weeks. The cocaine self-administration sessions were performed at three time points: at baseline (pre-TMS, session 1), after 4 days of rTMS (session 2), and after 13 days of rTMS (session 3). During each self-administration session, the outcome measure was the number of choices for cocaine.

RESULTS

The results showed a significant group by time effect (p = 0.02), where the choices for cocaine decreased between sessions 2 and 3 in the high frequency group. There was no effect of rTMS on cocaine self-administration in the low frequency or sham groups.

CONCLUSION

Taken in the context of the existing literature, these results contribute to the data showing that high frequency rTMS to the prefrontal cortex may serve as a potential treatment for CUD.