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Background: This systematic review and meta‐analysis aimed to assess the effectiveness of non‐invasive brain stimulation (NIBS), including repetitive transcranial magnetic stimulation (rTMS) and transcranial electrical stimulation (tES), as a neurological intervention for degenerative cerebellar ataxia (DCA) based on preregistration (PROSPERO: CRD42023379192). Objective: We aimed to explore clinical outcomes and examine the parameters associated with NIBS efficacy in DCA patients. Methods: The PubMed, Cochrane Library, CHINAL, and PEDro databases were searched for relevant randomized controlled trials (RCTs). Data extraction, quality assessment, and heterogeneity analyses were conducted; the Grading, Recommendations, Assessment, Development, and Evaluation was used to assess the quality of evidence and a meta‐analysis was performed. Results: Seventeen RCTs that included 661 patients on the scale for assessment and rating of ataxia (SARA) and 606 patients on the International Cooperative Ataxia Rating Scale (ICARS) were included. These RCTs showed a serious risk of bias (RoB) and low certainty of evidence for both outcomes. NIBS significantly reduced SARA (MD = −2.49, [95% confidence interval: −3.34, −1.64]) and ICARS (−5.27 [−7.06, −3.47]); the subgroup analysis showed significant effects: rTMS and tES reduced both outcomes. However, there were no significant differences in the effects of rTMS and tES. Additional subgroup analysis indicated the impact of rTMS frequency and the total number of tES sessions on ataxia. Conclusion: Non‐invasive brain stimulation may reduce ataxia in DCA patients, but the estimated effect size may change in future studies because the RoB was serious and the certainty of evidence was low, and the heterogeneity was high. To establish evidence for selecting NIBS methods and parameters, continued high‐quality RCTs are required. [ABSTRACT FROM AUTHOR]

Research suggests a potential of gamma oscillation entrainment for enhancing memory in Alzheimer's disease and healthy subjects. Gamma entrainment can be accomplished with oscillatory electrical, but also sensory stimulation. However, comparative studies between sensory stimulation and transcranial alternating current stimulation (tACS) effects on memory processes are lacking. This study examined the effects of rhythmic gamma auditory stimulation (rAS) and temporal gamma‐tACS on verbal long‐term memory (LTM) and working memory (WM) in 74 healthy individuals. Participants were assigned to two groups according to the stimulation techniques (rAS or tACS). Memory was assessed in three experimental blocks, in which each participant was administered with control, 40, and 60 Hz stimulation in counterbalanced order. All interventions were well‐tolerated, and participants reported mostly comparable side effects between real stimulation (40 and 60 Hz) and the control condition. LTM immediate and delayed recall remained unaffected by stimulations, while immediate recall intrusions decreased during 60 Hz stimulation. Notably, 40 Hz interventions improved WM compared to control stimulations. These results highlight the potential of 60 and 40 Hz temporal cortex stimulation for reducing immediate LTM recall intrusions and improving WM performance, respectively, probably due to the entrainment of specific gamma oscillations in the auditory cortex. The results also shed light on the comparative effects of these neuromodulation tools on memory functions, and their potential applications for cognitive enhancement and in clinical trials. We compared the effects of a single session online gamma‐rhythmic auditory stimulation (rAS) and temporal gamma‐transcranial alternating current stimulation (tACS) on memory processes in healthy individuals. Findings reveal that 40 Hz stimulation enhances verbal working memory (i.e., digit span backward score), while 60 Hz stimulation reduces immediate recall intrusions rate during a declarative long‐term memory task. These frequency‐specific effects suggest a potential role for auditory cortex activity in immediate cognitive demands, shedding light on the mechanisms of gamma frequency neuromodulation. [ABSTRACT FROM AUTHOR]

Non‐invasive brain stimulation techniques offer therapeutic potential for neurological and psychiatric disorders. However, current methods are often limited in their stimulation depth. The novel transcranial temporal interference stimulation (tTIS) aims to overcome this limitation by non‐invasively targeting deeper brain regions. In this study, we aimed to evaluate the efficacy of tTIS in modulating alpha activity during a mental rotation task. The effects of tTIS were compared with transcranial alternating current stimulation (tACS) and a sham control. Participants were randomly assigned to a tTIS, tACS, or sham group. They performed alternating blocks of resting and mental rotation tasks before, during, and after stimulation. During the stimulation blocks, participants received 20 min of stimulation adjusted to their individual alpha frequency (IAF). We assessed shifts in resting state alpha power, event‐related desynchronization (ERD) of alpha activity during mental rotation, as well as resulting improvements in behavioral performance. Our results indicate tTIS and tACS to be effective in modulating cortical alpha activity during mental rotation, leading to an increase in ERD from pre‐ to poststimulation as well as compared to sham stimulation. However, this increase in ERD was not correlated with enhanced mental rotation performance, and resting state alpha power remained unchanged. Our findings underscore the complex nature of tTIS and tACS efficacy, indicating that stimulation effects are more observable during active cognitive tasks, while their impacts are less pronounced on resting neuronal systems. Our study adds to the limited human research on the novel tTIS technique, which holds the potential for non‐invasive deep brain stimulation. We show that while tTIS and tACS can modulate cortical alpha activity during an active cognitive task, they do not improve behavioral performance or affect resting state alpha power. This underscores the task‐specific effectiveness of these techniques, suggesting their therapeutic potential is most effective during active cognitive engagement. [ABSTRACT FROM AUTHOR]

Both the primary motor cortex (M1) and the cerebellum are crucial for postural stability and deemed as potential targets for non‐invasive brain stimulation (NIBS) to enhance balance performance. However, the optimal target remains unknown. The purpose of this study was to compare the role of M1 and the cerebellum in modulating balance performance in young healthy adults using facilitatory 5 Hz repetitive transcranial magnetic stimulation (rTMS). Twenty‐one healthy young adults (mean age = 27.95 ± 1.15 years) received a single session of 5 Hz rTMS on M1 and the cerebellum in a cross‐over order with a 7‐day washout period between the two sessions. Three balance assessments were performed on the Biodex Balance system SD: Limits of Stability (LOS), modified Clinical Test of Sensory Interaction on Balance (mCTSIB), and Balance Error Scoring System (BESS). No significant effect of rTMS was found on the LOS. The effect of rTMS on the mCTSIB was mediated by stimulation target, proprioception, and vision (p =.003, ηp2 = 0.37). Cerebellar rTMS improved the mCTSIB sway index under eyes closed‐foam surface condition (p =.02), whereas M1 rTMS did not result in improvement on the mCTSIB. The effect of rTMS on the BESS was mediated by stimulation target, posture, and proprioception (p =.049, ηp2 = 0.14). Cerebellar rTMS enhanced reactive balance performance during most sensory deprived conditions. [ABSTRACT FROM AUTHOR]

Introduction: Long COVID occurs when numerous symptoms begin 3 weeks after acute infection and last for 12 months or more. High‐definition transcranial direct current stimulation (HD‐tDCS) has been tested in patients with COVID‐19; however, previous studies did not investigate the HD‐tDCS use combined with inspiratory muscle training (IMT) for respiratory sequelae of long COVID. Case presentation: Six individuals (four women and two men) aged between 29 and 71 years and presenting with respiratory sequelae of long COVID were included. They were submitted to an intervention that comprised HD‐tDCS combined with IMT twice a week for 5 weeks. Lung function and respiratory muscle assessments were performed at baseline and after 5 weeks of intervention. Implications on physiotherapy practice: HD‐tDCS may enhance the IMT effects by increasing respiratory muscle strength, efficiency, and lung function of individuals with long COVID. [ABSTRACT FROM AUTHOR]

Introduction: Despite its high lifetime prevalence rate and the elevated disability caused by posttraumatic stress disorder (PTSD), treatments exhibit modest efficacy. In consideration of the abnormal connectivity between the dorsolateral prefrontal cortex (DLPFC) and amygdala in PTSD, several randomized controlled trials (RCTs) addressing the efficacy of different noninvasive brain stimulation (NIBS) modalities for PTSD management have been undertaken. However, previous RCTs have reported inconsistent results. The current network meta‐analysis (NMA) aimed to compare the efficacy and acceptability of various NIBS protocols in PTSD management. Methods: We systematically searched ClinicalKey, Cochrane Central Register of Controlled Trials, Embase, ProQuest, PubMed, ScienceDirect, Web of Science, and ClinicalTrials.gov to identify relevant RCTs. The targeted RCTs was those comparing the efficacy of NIBS interventions, such as transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and transcutaneous cervical vagal nerve stimulation, in patients with PTSD. The NMA was conducted using a frequentist model. The primary outcomes were changes in the overall severity of PTSD and acceptability (to be specific, rates of dropouts for any reason). Results: We identified 14 RCTs that enrolled 686 participants. The NMA demonstrated that among the investigated NIBS types, high‐frequency rTMS over bilateral DLPFCs was associated with the greatest reduction in overall PTSD severity. Further, in comparison with the sham controls, excitatory stimulation over the right DLPFC with/without excitatory stimulation over left DLPFC were associated with significant reductions in PTSD‐related symptoms, including depression and anxiety symptoms, and overall PTSD severity. Conclusions: This NMA demonstrated that excitatory stimulation over the right DLPFC with or without excitatory stimulation over left DLPFC were associated with significant reductions in PTSD‐related symptoms. Trial registration: PROSPERO CRD42023391562. [ABSTRACT FROM AUTHOR]

Transcranial pulsed current stimulation (tPCS) is a noninvasive brain stimulation technique that has aroused considerable attention in recent years. This review aims to provide an overview of the existing literature on tPCS, examine the scope and nature of previous research, investigate its underlying mechanisms, and identify gaps in the literature. Searching online databases resulted in 36 published tPCS studies from inception until May 2023. These studies were categorized into three groups: human studies on healthy individuals, human studies on clinical conditions, and animal studies. The findings suggest that tPCS has the potential to modulate brain excitability by entraining neural oscillations and utilizing stochastic resonance. However, the underlying mechanisms of tPCS are not yet fully understood and require further investigation. Furthermore, the included studies indicate that tPCS may have therapeutic potential for neurological diseases. However, before tPCS can be applied in clinical settings, a better understanding of its mechanisms is crucial. Hence, the tPCS studies were categorized into four types of research: basic, strategic, applied, and experimental research, to identify the nature of the literature and gaps. Analysis of these categories revealed that tPCS, with its diverse parameters, effects, and mechanisms, presents a wide range of research opportunities for future investigations. Transcranial pulsed current stimulation (tPCS) is a cutting‐edge, noninvasive brain stimulation method that utilizes pulsatile current to modulate brain oscillations. It shares parameters and effects with other transcranial electric stimulation techniques like transcranial alternating current stimulation (frequency‐dependent) and transcranial direct current stimulation (polarity dependent). It is believed to have unique mechanisms for personalized treatment. Despite the limited literature, research suggests that tPCS can modulate cortical excitability through entrainment and stochastic resonance. Further studies are recommended to investigate its underlying mechanisms and the effects of different parameters. [ABSTRACT FROM AUTHOR]

Brain rhythms of sleep reflect neuronal activity underlying sleep‐associated memory consolidation. The modulation of brain rhythms, such as the sleep slow oscillation (SO), is used both to investigate neurophysiological mechanisms as well as to measure the impact of sleep on presumed functional correlates. Previously, closed‐loop acoustic stimulation in humans targeted to the SO Up‐state successfully enhanced the slow oscillation rhythm and phase‐dependent spindle activity, although effects on memory retention have varied. Here, we aim to disclose relations between stimulation‐induced hippocampo‐thalamo‐cortical activity and retention performance on a hippocampus‐dependent object‐place recognition task in mice by applying acoustic stimulation at four estimated SO phases compared to sham condition. Across the 3‐h retention interval at the beginning of the light phase closed‐loop stimulation failed to improve retention significantly over sham. However, retention during SO Up‐state stimulation was significantly higher than for another SO phase. At all SO phases, acoustic stimulation was accompanied by a sharp increase in ripple activity followed by about a second‐long suppression of hippocampal sharp wave ripple and longer maintained suppression of thalamo‐cortical spindle activity. Importantly, dynamics of SO‐coupled hippocampal ripple activity distinguished SOUp‐state stimulation. Non‐rapid eye movement (NREM) sleep was not impacted by stimulation, yet preREM sleep duration was effected. Results reveal the complex effect of stimulation on the brain dynamics and support the use of closed‐loop acoustic stimulation in mice to investigate the inter‐regional mechanisms underlying memory consolidation. [ABSTRACT FROM AUTHOR]

Objective: Low‐intensity transcranial focused ultrasound (TUS) is a novel method for neuromodulation. We aimed to study the feasibility of stimulating the bilateral primary motor cortices (M1) with accelerated theta‐burst TUS (a‐tbTUS) on neurophysiologic and clinical outcomes in Parkinson's disease (PD). Methods: Patients were randomly assigned to receive active or sham a‐tbTUS for the first visit and the alternate condition on the second visit, at least 10 days apart. a‐tbTUS was administered in three consecutive sonications at 30‐minute intervals. We used an accelerated protocol to produce an additive effect of stimulation. Patients were studied in the OFF‐medication state. Transcranial magnetic stimulation (TMS)‐elicited motor‐evoked potentials (MEPs) were used to assess motor cortical excitability before and after TUS. Clinical outcomes after a‐tbTUS administration were assessed using the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS‐UPDRS)‐III. Results: A total of 20 visits were conducted in 10 PD patients. Compared to the baseline, TMS‐elicited MEP amplitudes significantly increased following active but not sham sonication (P = 0.0057). MEP amplitudes were also higher following a‐tbTUS than sham sonication (P = 0.0064). There were no statistically significant changes in MDS‐UPDRS‐III scores with active or sham a‐tbTUS. Conclusions: a‐tbTUS increases motor cortex excitability and is a feasible non‐invasive neuromodulation strategy in PD. Future studies should determine optimal dosing parameters and the durability of neurophysiologic and clinical outcomes in PD patients. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

The article focuses on the exploration of noninvasive brain stimulation techniques for enhancing sports performance while considering the associated ethical implications. Topics include the potential benefits of combining resistance training with brain stimulation, the need for further investigation into the side effects and regulatory aspects of these techniques, and the current understanding of the neural mechanisms involved in performance enhancement.

Transcranial direct current stimulation (tDCS) is a non‐invasive brain stimulation technique that can modulate brain activity through the application of low‐intensity electrical currents. Based on its reported effects on corticospinal excitability (CSE), tDCS has been used to study cognition in healthy individuals and reduce symptoms in a variety of clinical conditions. Despite its increasing popularity as a research and clinical tool, high interindividual variability has been reported in the response to protocols using transcranial magnetic stimulation (TMS) to assess tDCS‐induced changes in CSE leading to several nonsignificant findings. In this systematic review, studies that reported no significant modulation of CSE following tDCS were identified from PubMed and Embase (Ovid) databases. Forty‐three articles were identified where demographic, TMS and tDCS parameters were extracted. Overall, stimulation parameters, CSE measurements and participant characteristics were similar to those described in studies reporting positive results and were likewise heterogeneous between studies. Small sample sizes and inadequate blinding were notable features of the reviewed studies. This systematic review suggests that studies reporting nonsignificant findings do not markedly differ from those reporting significant modulation of CSE. [ABSTRACT FROM AUTHOR]

Aim: In recent decades, the prevalence of amphetamine and methamphetamine use disorders has at least doubled in some regions/countries, with accompanying high risks of drug overdose‐associated mortality. Noninvasive brain stimulation (NIBS) methods may be effective treatments. However, the comparative efficacy of the NIBS protocol for amphetamine/methamphetamine use disorder (AUD/MUD) remains unknown to date. The aim of this network meta‐analysis (NMA) was to compare the efficacy and acceptability of various NIBS methods/protocols for AUD/MUD management. Methods: A frequentist model‐based NMA was conducted. We included randomized controlled trials (RCTs) that investigated the efficacy of NIBS and guideline‐recommended pharmacologic treatments to reduce craving severity in patients with either AUD or MUD. Results: Twenty‐two RCTs including 1888 participants met the eligibility criteria. Compared with the sham/placebo group (study = 19, subjects = 891), a combination of intermittent theta burst stimulation over the left dorsolateral prefrontal cortex (DLPFC) and continuous TBS over the left ventromedial prefrontal cortex (study = 1, subjects = 19) was associated with the largest decreases in craving severity [standardized mean difference (SMD) = −1.50; 95% confidence intervals (95%CIs) = −2.70 to −0.31]. High‐frequency repetitive transcranial magnetic stimulation over the left DLPFC was associated with the largest improvements in depression and quality of sleep (study = 3, subjects = 86) (SMD = −2.48; 95%CIs = −3.25 to −1.71 and SMD = −2.43; 95%CIs = −3.38 to −1.48, respectively). The drop‐out rate of most investigated treatments did not significantly differ between groups. Conclusion: The combined TBS protocol over the prefrontal cortex was associated with the greatest improvement in craving severity. Since few studies were available for inclusion, additional large‐scale randomized controlled trials are warranted. [ABSTRACT FROM AUTHOR]

Summary: Sleep spindles are a hallmark electroencephalographic feature of non‐rapid eye movement sleep, and are believed to be instrumental for sleep‐dependent memory reactivation and consolidation. However, direct proof of their causal relevance is hard to obtain, and our understanding of their immediate neurophysiological consequences is limited. To investigate their causal role, spindles need to be targeted in real‐time with sensory or non‐invasive brain‐stimulation techniques. While fully automated offline detection algorithms are well established, spindle detection in real‐time is highly challenging due to their spontaneous and transient nature. Here, we present the real‐time spindle detector, a robust multi‐channel electroencephalographic signal‐processing algorithm that enables the automated triggering of stimulation during sleep spindles in a phase‐specific manner. We validated the real‐time spindle detection method by streaming pre‐recorded sleep electroencephalographic datasets to a real‐time computer system running a Simulink® Real‐Time™ implementation of the algorithm. Sleep spindles were detected with high levels of Sensitivity (~83%), Precision (~78%) and a convincing F1‐Score (~81%) in reference to state‐of‐the‐art offline algorithms (which reached similar or lower levels when compared with each other), for both naps and full nights, and largely independent of sleep scoring information. Detected spindles were comparable in frequency, duration, amplitude and symmetry, and showed the typical time–frequency characteristics as well as a centroparietal topography. Spindles were detected close to their centre and reliably at the predefined target phase. The real‐time spindle detection algorithm therefore empowers researchers to target spindles during human sleep, and apply the stimulation method and experimental paradigm of their choice. [ABSTRACT FROM AUTHOR]

Background and Aims: Non‐invasive brain stimulation (NIBS) methods have showed promising results for the treatment of tobacco use disorder, but little is known about the efficacy of NIBS on sustained tobacco abstinence. We aimed to assess its effectiveness for long‐term smoking cessation. Methods: Systematic review and meta‐analysis of randomized controlled trials (RCT). PubMed, Cochrane library, Embase, PsycINFO and clinical trials registries were systematically searched for relevant studies up to May 2021. Relevant studies included adult smokers seeking smoking cessation, included in an RCT using NIBS [specifically repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS)], and with follow‐up of more than 4 weeks. There were no restrictions on location. Abstinence rates in the active NIBS groups were compared with abstinence rates in sham NIBS or in usual treatment groups, from 4 weeks to 12 months following the quit attempt. Smoking abstinence was measured on an intention‐to‐treat basis and we used risk ratios (RRs) as measures of effect size. Results: Seven studies were included (n = 699 patients). In all included studies, the control groups were receiving sham NIBS and only data from 3 to 6 months were analysable. By pooling the seven included studies, the RR of sustained abstinence of any form of NIBS relative to sham NIBS was 2.39 [95% confidence interval (CI) = 1.26–4.55; I2 = 40%]. Subgroup analyses found that the RR was even higher when excitatory rTMS was used on the left dorsolateral prefrontal cortex (RR = 4.34; 95% CI = 1.69–11.18; I2 = 0%) or when using deep rTMS targeting the lateral prefrontal cortex and insula bilaterally (RR = 4.64; 95% CI = 1.61–13.39; I2 = 0%). A high risk of bias was found in four included studies. We also determined, using grades of recommendation, assessment, development and evaluation, that overall there was a low level of confidence in the results. Conclusion: Non‐invasive brain stimulation (NIBS) may improve smoking abstinence rates from 3 to 6 months after quitting smoking, compared with sham NIBS or usual treatment. [ABSTRACT FROM AUTHOR]

Background: Neuroplasticity in adolescents is distinct from that of adults. Literature pertaining to neuroplasticity in schizophrenia is limited to adult populations. Aim: We aimed to assess baseline (or resting) cortical excitability and cortical plasticity in adolescents with schizophrenia using the transcranial magnetic stimulation-electromyography (TMS-EMG) protocol. Methods: Twenty adolescent cases with schizophrenia and 20 age and gender matched healthy controls were studied using a crossover design. Single pulse TMS elicited resting motor threshold (RMT) and motor evoked potentials (MEPs) were assessed. Cortical plasticity was determined by tracking MEPs after a single session continuous theta burst stimulation (cTBS) and intermittent theta burst stimulation (iTBS) up to 120 min at 12 intervals. Results: Baseline (or resting) cortical excitability was found to be significantly lower in cases compared with controls. Response patterns to cTBS and iTBS were similar between the crossover. While cTBS led to inhibitory response, iTBS had an excitatory effect in both the groups. In the cases, while cTBS led to significantly greater initial inhibitory response, iTBS led to significantly lower excitatory response, compared with controls. The time taken to return to baseline excitability was significantly longer after receiving cTBS for cases, compared with controls. Conclusions: iTBS and cTBS lead to excitatory and inhibitory response, representing classical long-term depression and long-term potentiation effects, respectively, in both cases and controls. We conclude that adolescents with schizophrenia have significantly lower baseline (resting) cortical excitability as well as significantly greater inhibitory plasticity; excitatory plasticity is significantly lower. [ABSTRACT FROM AUTHOR]

Aim: Emerging evidence suggests that transcranial direct current stimulation (tDCS) has anxiolytic effects and may enhance emotional processing of threat and reduce threat‐related attentional bias. Panic disorder (PD) is considered to be a fear network disorder along with prefrontal activity alterations. We aim to assess the effect of tDCS on clinical and physiological parameters in PD for the first time. Methods: In this triple‐blind randomized sham‐controlled pilot study, 30 individuals with PD were allocated into active and sham groups to receive 10 sessions of tDCS targeting the dorsolateral prefrontal cortex bilaterally at 2 mA for 20‐min duration over 2 weeks. The clinical severity, threat‐related attentional bias, interoceptive accuracy, and emotional recognition were assessed before, immediately after, and 1 month after tDCS. Results: Active tDCS, in comparison to sham, did not elicit more favorable clinical and neuropsychological/physiological outcomes in PD. Conclusion: The present study provides the first clinical and neurobehavioral results of prefrontal tDCS in PD and indicates that prefrontal tDCS was not superior to sham in PD. [ABSTRACT FROM AUTHOR]

Background and aims: Nicotine is a highly addictive substance in tobacco products that dysregulates several neurotransmitters in the brain and impairs executive function. Non‐invasive brain stimulation (NIBS) methods such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are promising treatments for nicotine dependence. We investigated the efficacy and acceptability of NIBS in managing smoking cessation through a systematic review and network meta‐analysis (NMA). Methods: We conducted a systematic review to identify randomized controlled trials (RCTs) that investigated the efficacy of NIBS for smoking cessation. All pairwise meta‐analyses and NMA procedures were conducted using random‐effects and frequentist models. The co‐primary outcomes were (1) the change in number of cigarettes smoked per day (change in frequency of smoking) in patients with nicotine dependence after NIBS and (2) acceptability (the dropout rate). The effect sizes for co‐primary outcomes of change in frequency of smoking and acceptability were assessed according to standardized mean difference (SMD) and odds ratio, respectively. Results: Twelve RCTs with 710 participants (mean age: 44.2 years, 31.2% female) were included. Compared with the sham control, 10‐Hz rTMS over the left dorsolateral prefrontal cortex (DLPFC) was associated with the largest changes in smoking frequency [SMD = −1.22, 95% confidence interval (95% CI) = −1.77 to −0.66]. The 2‐mA bifrontal tDCS (SMD = −0.97, 95% CI = −1.32 to −0.62) and 10‐Hz deep rTMS over the bilateral DLPFC with cue provocation (SMD = −0.77, 95% CI = −1.20 to −0.34) were associated with a significantly larger decrease in smoking frequency versus the sham. None of the investigated NIBSs was associated with dropout rates significantly different from those of the sham control groups. Conclusion: Prefrontal non‐invasive brain stimulation interventions appear to reduce the number of cigarettes smoked with good acceptability. [ABSTRACT FROM AUTHOR]

Transcranial magnetic stimulation (TMS) motor mapping is a safe, non‐invasive method that can be used to study corticomotor organization. Motor maps are typically acquired at rest, and comparisons to maps obtained during muscle activation have been both limited and contradictory. Understanding the relationship between functional activation of the corticomotor system as recorded by motor mapping is crucial for their use clinically and in research. The present study utilized robotic TMS paired with personalized neuro‐navigation to examine the relationship between resting and active motor map measures and their relationship with motor performance. Twenty healthy right‐handed participants underwent resting and active robotic TMS motor mapping of the first dorsal interosseous to 10% maximum voluntary contraction. Motor map parameters including map area, volume, and measures of map centrality were compared between techniques using paired sample tests of difference and Bland–Altman plots and analysis. Map area, volume, and hotspot magnitude were larger in the active motor maps, while map center of gravity and hotspot locations remained consistent between both maps. No associations were observed between motor maps and motor performance as measured by the Purdue Pegboard Test. Our findings support previous suggestions that maps scale with muscle contraction. Differences in mapping outcomes suggest rest and active motor maps may reflect functionally different corticomotor representations. Advanced analysis methods may better characterize the underlying neurophysiology of both types of motor mapping. [ABSTRACT FROM AUTHOR]

The role of transcranial direct current stimulation (tDCS) as an ergogenic aid is receiving attention from scientists to optimize sport performance. Most studies have examined the effects of tDCS on endurance performance during continuous tasks, while the effect of tDCS on high-intensity intermittent tasks has been less investigated. Therefore, this study aimed to explore the acute effects of tDCS on sprint performance and ratings of perceived exertion (RPE) during a repeated sprint ability (RSA) task. Twenty-five healthy males (age: 22.0 ± 2.5 years) participated in a randomized crossover study consisting of three experimental sessions (anodal, cathodal or sham tDCS) separated by 1 week. Each session consisted of (I) tDCS protocol (15 min at 2 mA applied over the dorsolateral prefrontal cortex [DLPFC]), (II) warm-up and (III) RSA task (ten 30-m running sprints separated by 30 s). Total time and RPE values were recorded for each sprint. The two-way ANOVA applied on sprint time did not reveal a significant main effect of tDCS condition (p =.200) neither a significant tDCS condition × number of sprint interaction (p =.716). Similarly, no significant differences were observed for the fatigue index (p =.449), RSAmean (p =.200) or RPE after each sprint (p range =.116–.890). The magnitude of the differences between the tDCS conditions ranged from negligible to small (effect sizes ≤ 0.33). These results suggest that the application of tDCS over the DLPFC is not effective to increase sprint performance or reduce RPE during a RSA task. HIGHLIGHTS Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that could modulate neuromuscular performance. This study aimed to explore the short-term effects of tDCS on sprint performance and ratings of perceived exertion (RPE) during a repeated sprint ability (RSA) task. The application of either ANODAL or CATHODAL tDCS over the DLPFC for 15 minutes did not affect the sprint time of single repeated sprints or the overall metrics of RSA performance (RSAmean and fatigue index). The application of either ANODAL or CATHODAL tDCS over the DLPFC for 15 minutes did not affect the ratings of perceived exertion measured during the repeated sprints task. [ABSTRACT FROM AUTHOR]

Summary: Transcranial direct current stimulation (tDCS) is becoming an increasingly popular technique for altering eating behaviors. Recent research suggests a possible eating behavior trait‐dependent effect of tDCS. However, studies recruit participant populations with heterogeneous trait characteristics, including "healthy" individuals who do not present with eating behavior traits suggesting susceptibility to overconsumption. The present review considers the effects of tDCS across eating‐related measures and explores whether a trait‐dependent effect is evident across the literature. A literature search identified 28 articles using sham‐controlled tDCS to modify eating‐related measures. Random effects meta‐analyses were performed, with subgroup analyses to identify differences between "healthy" and trait groups. Trivial overall effects (g = −0.12 to 0.09) of active versus sham tDCS were found. Subgroup analyses showed a more consistent effect for trait groups, with small and moderate effect size (g = −1.03 to 0.60), suggesting tDCS is dependent on participants' eating behavior traits. Larger effect sizes were found for those displaying traits associated with study outcomes (e.g., heightened food cravings). "Healthy" individuals appear to be unresponsive to stimulation. Based on this meta data, future work should recruit those with eating behavior trait susceptibilities to overconsumption, focusing on those who present with traits associated with the outcome of interest. [ABSTRACT FROM AUTHOR]

Brain stimulation has become one of the most acceptable therapeutic approaches in recent years and a powerful tool in the remedy against neurological diseases. Brain stimulation is achieved through the application of electric currents using non‐invasive as well as invasive techniques. Recent technological advancements have evolved into the development of precise devices with capacity to produce well‐controlled and effective brain stimulation. Currently, most used non‐invasive techniques are repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), whereas the most common invasive technique is deep brain stimulation (DBS). In last decade, application of these brain stimulation techniques has not only exploded but also expanded to wide variety of neurological disorders. Therefore, in the current review, we will provide an overview of the potential of both non‐invasive (rTMS and tDCS) and invasive (DBS) brain stimulation techniques in the treatment of such brain diseases. [ABSTRACT FROM AUTHOR]

Introduction: Given rapid global population aging, developing interventions against age-associated cognitive decline is an important medical and societal goal. We evaluated a cognitive training protocol combined with transcranial direct current stimulation (tDCS) on trained and non-trained functions in non-demented older adults. Methods: Fifty-six older adults (65-80 years) were randomly assigned to one of two interventional groups, using age and baseline performance as strata. Both groups performed a nine-session cognitive training over 3 weeks with either concurrent anodal tDCS (atDCS, 1 mA, 20 minutes) over the left dorsolateral prefrontal cortex (target intervention) or sham stimulation (control intervention). Primary outcome was performance on the trained letter updating task immediately after training. Secondary outcomes included performance on other executive and memory (near and far transfer) tasks. All tasks were administered at baseline, post-intervention, and at 1- and 7-month follow-up assessments. Prespecified analyses to investigate treatment effects were conducted using mixed-model analyses. Results: No between-group differences emerged in the trained letter updating and Markov decision-making tasks at post-intervention and at follow-up timepoints. Secondary analyses revealed group differences in one near-transfer task: Superior n-back task performance was observed in the tDCS group at post-intervention and at followup. No such effectswere observed for the other transfer tasks. Improvements in workingmemory were associated with individually induced electric field strengths. Discussion: Cognitive training with atDCS did not lead to superior improvement in trained task performance compared to cognitive training with sham stimulation. Thus, our results do not support the immediate benefit of tDCS-assisted multi-session cognitive training on the trained function. As the intervention enhanced performance in a near-transfer working memory task, we provide exploratory evidence for effects on non-trainedworking memory functions in non-demented older adults that persist over a period of 1 month. [ABSTRACT FROM AUTHOR]

Mental rotation, the ability to manipulate mental images, is an important function in human cognition. This systematic review and meta‐analysis investigates the potential of non‐invasive brain stimulation in modulation of this component of visuo‐spatial perception. The PubMed database was reviewed prior to 31 September 2020 on randomized controlled trials investigating the effects of repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS), and transcranial alternating current stimulation (tACS) on the mental rotation ability in healthy persons. A total of 17 studies (including 485 subjects) matched our inclusion criteria. Within their scope, overall, 46 sham‐controlled experiments were performed. Methodology and results of each experiment are presented in a meta‐analysis. The data show a large variety of methods and effects. The influence of (1) stimulation‐technique (tDCS, tACS, and rTMS), (2) stimulation protocol (anodal, cathodal, bilateral tDCS, tACS, high‐frequency rTMS, low‐frequency rTMS, paired pulse rTMS, and theta burst stimulation), (3) stimulation timing (preconditioning and simultaneous), (4) stimulation location (left, right hemisphere, frontal, and parietal area), and (5) stimulus type (bodily and non‐bodily) is discussed. The data indicate a beneficial effect of anodal tDCS and of tACS and no effect of cathodal tDCS on the mental rotation ability. Bilateral tDCS protocols both improved and worsened the parameters assessed. The small effect sizes obtained in mostly rTMS experiments require cautious interpretation. [ABSTRACT FROM AUTHOR]

Non‐invasive brain stimulation (NIBS) techniques have been widely used to study central nervous system pathophysiology and have revealed new information about the functional roles of specific brain structures. This review first outlines the basic technologies and neural mechanisms associated with NIBS. Transcranial magnetic stimulation (TMS) was first utilized to obtain motor‐evoked potentials, which reflect corticospinal tract function. Later, studies using repetitive TMS and patterned TMS‐like theta‐burst stimulation reported the presence of aftereffects, which can enhance or inhibit cortical excitability depending on the stimulus frequency or continuous/intermittent stimulation. Over the past two decades, transcranial electrical stimulation has become increasingly popular for neuromodulation, which includes direct current stimulation (tDCS) and alternating current stimulation (tACS). While tDCS modulates cortical excitability depending on the stimulation polarity, tACS exerts its effects in a frequency‐phase–dependent manner. Although entrainment may be an important underlying mechanism, the recorded aftereffects are likely due to spike‐timing–dependent plasticity. Second, recent innovations using NIBS to induce short‐term cortical plasticity are highlighted. State‐dependent or informed open‐loop stimulation can be used to explore the interactions between endogenous cortical oscillations and TMS. Electroencephalographic oscillations prior to TMS stimulation reflect instantaneous cortical excitability depending on the stimulation power and phase, and repetitive TMS at a certain EEG state can enhance cortical excitability. Finally, temporal deafferentation of the peripheral nerve induced by a modified ischemic nerve block can modulate sensorimotor function after tourniquet deflation. Overall, NIBS techniques are promising tools for investigating human brain functions and developing new protocols for neurorehabilitation. [ABSTRACT FROM AUTHOR]

Background: In this study, we investigate the capacity of two different non‐invasive brain stimulation (NIBS) techniques (anodal transcranial direct current stimulation (anodal tDCS) and high‐frequency transcranial random noise stimulation (hf‐tRNS)) regarding the relationship between stimulation duration and their efficacy in inducing long‐lasting changes in motor cortical excitability. Methods: Fifteen healthy subjects attended six experimental sessions (90 experiments in total) and underwent both anodal tDCS of 7, 13, and 20 min duration, as well as high‐frequency 1mA‐tRNS of 7, 13, and 20 min stimulation duration. Sessions were performed in a randomized order and subjects were blinded to the applied methods. Results: For anodal tDCS, no significant stable increases of motor cortical excitability were observed for either stimulation duration. In contrast, for hf ‐tRNS a stimulation duration of 7 min resulted in a significant increase of motor cortical excitability lasting from 20 to 60 min poststimulation. While an intermediate duration of 13 min hf‐tRNS failed to induce lasting changes in motor cortical excitability, a longer stimulation duration of 20 min hf‐tRNS led only to significant increases at 50 min poststimulation which did not outlast until 60 min poststimulation. Conclusion: Hf‐tRNS for a duration of 7 min induced robust increases of motor cortical excitability, suggesting an indirect proportional relationship between stimulation duration and efficacy. While hf‐tRNS appeared superior to anodal tDCS in this study, further systematic and randomized experiments are necessary to evaluate the generalizability of our observations and to address current intensity as a further modifiable contributor to the variability of transcranial brain stimulation. [ABSTRACT FROM AUTHOR]

Transcranial direct current stimulation (tDCS) has been proposed to be able to modulate different cognitive functions. However, recent meta‐analyses conclude that its efficacy is still in question. Recently, an increase in subjects' propensity to mind‐wander has been reported as a consequence of anodal stimulation of the left dorsolateral prefrontal cortex (Axelrod et al., Proceedings of the National Academy of Sciences of the United States of America, 112, 2015). In addition, an independent group found a decrease in mind wandering after cathodal stimulation of the same region. These findings seem to indicate that high‐level cognitive processes such as mind wandering can reliably be influenced by non‐invasive brain stimulation. However, these previous studies used low sample sizes and are as such subject to concerns regarding the replicability of their findings. In this registered report, we implement a high‐powered replication of Axelrod et al. (2015) finding that mind‐wandering propensity can be increased by anodal tDCS. We used Bayesian statistics and a preregistered sequential‐sampling design resulting in a total sample size of N = 192 participants collected across three different laboratories. Our findings show support against a stimulation effect on self‐reported mind‐wandering scores. The effect was small, in the opposite direction as predicted and not reliably different from zero. Using a Bayes Factor specifically designed to test for replication success, we found strong evidence against a successful replication of the original study. Finally, even when combining data from both the original and replication studies, we could not find evidence for an effect of anodal stimulation. Our results underline the importance of designing studies with sufficient power to detect evidence for or against behavioural effects of non‐invasive brain stimulation techniques, preferentially using robust Bayesian statistics in preregistered reports. [ABSTRACT FROM AUTHOR]

Background: Non‐invasive brain stimulation (NIBS) techniques such as repetitive transcranial magnetic stimulation (rTMS), as well as transcranial direct current stimulation (tDCS) electrically stimulate the brain and modify brain activity to suppress pain. This method is emerging as a potential clinical intervention against migraine. Objective: To quantitatively review the efficacy of rTMS and tDCS in randomized controlled trials (RCTs) in modifying headache intensity and frequency of headache attacks in patients suffering from migraine. Methods: We searched 5 databases: PubMed, EMBASE, Web of Science, Cochrane Library, and Scopus for articles from January 2000 to September 2018. Any RCT regarding the efficacy on rTMS and tDCS on patients with migraine, was considered to be included. A random effects meta‐analysis was performed to pool effect sizes of outcomes related to headache intensity or frequency of headache attacks. The methodological quality of the included RCTs was assessed using the Physiotherapy Evidence Database scale. Results: Nine RCTs with 276 participants in total (experimental group [EG] = 149; control group [CG] = 127) were included in this review. Five included articles used rTMS (EG = 81; CG = 80), and 4 used tDCS (EG = 68; CG = 47). Meta‐analysis of excitatory primary motor cortex (M1) stimulation showed significant effects on reducing headache intensity in patients with migraine (Hedges' g = −0.94; 95% CI, −1.28 to −0.59; P < .001, I2 = 18.39%) with a large effect size. Meta‐analysis of excitatory M1 stimulation showed significant effects on reducing frequency of headache attacks in patients with migraine, with a large effect size (Hedges' g = −0.88; 95% CI, −1.38 to −0.38; P = .001, I2 = 57.15%). Excitatory dorsolateral prefrontal cortex stimulation showed a significant effect on the headache intensity in patients with migraine (Hedges' g = −1.14; 95% CI, −2.21 to −0.07; P = .04, I2 = 61.86%) with a large effect size. However, reductions of frequency of headache attacks was not significant. Limitations: Potential differential effects of rTMS and tDCS, various sham methods, and potential overlapping headache disorders among included subjects may affect the estimation of effect sizes. Conclusion: Excitatory NIBS of the M1 is likely to reduce headache intensity and the frequency of headache attacks in patients with migraine. [ABSTRACT FROM AUTHOR]

Objective: Neuromodulation of regions involved in food processing is increasingly used in studies on eating behaviors, but results are controversial. We assessed the effects of anodal transcranial direct current stimulation (a‐tDCS) on food and body implicit preferences in patients with eating disorders (EDs). Method: Thirty‐six ED patients and 36 healthy females completed three sessions with a‐tDCS applied to the medial‐prefrontal cortex (mPFC), the right extrastriate body area (rEBA) or in sham mode. Each participant then completed three Implicit Association Tests (IATs) on tasty/tasteless food, underweight/overweight body images, flowers versus insects as control. Differences in latency between incongruent and congruent blocks were calculated (D score). Results: The tDCS by group interaction was significant for the IAT‐food D score, with patients showing weaker preference for tasty food than controls in sham, but not a‐tDCS sessions. In particular, rEBA stimulation significantly increased patients' D score compared to sham. Moreover, a‐tDCS over mPFC and rEBA selectively increased patients' reaction times in the incongruent blocks of the IAT‐food. Discussion: A‐tDCS on frontal and occipito‐temporal cortices modulated food preferences in ED patients. The effect was specific for food images and selective in patients, but not in healthy participants. These findings suggest that neuromodulation of these regions could affect implicit food attitudes. [ABSTRACT FROM AUTHOR]

Keywords: central fatigue; exercise; non-invasive brain stimulation; perception of effort EN central fatigue exercise non-invasive brain stimulation perception of effort 703 704 2 02/03/23 20230201 NES 230201 The neurophysiological mechanisms leading to fatigue during exercise have been investigated since the early 19 SP th sp century, and since the introduction of neuromodulation stimulation techniques, applied either at the cortical or spinal level, the understanding of such mechanisms has been improved. Amann and colleagues ([2]) highlighted the potential for transcranial direct current stimulation (tDCS) to alter central fatigue and motoneuronal output. These important methodological limitations should be considered with extreme concern among the scientific community as many experiments and commercial off-the-shelf tDCS devices claim that tDCS induces some neurophysiological mechanisms that have never been demonstrated or measured (Angius, Pascual-Leone et al., [5]). [Extracted from the article]

Moreover, with the daily-increasing number of studies reporting significant effects of tDCS, there are reports of tDCS null-effects as well. Specifically, 2 mA cathodal tDCS resulted in an excitability-enhancing effect and increased MEP amplitudes, whereas 1 mA cathodal tDCS decreased corticocortical and corticospinal excitability (Batsikadze I et al i . Due to the state-dependency effects of neuromodulatory tDCS, the stimulation itself could have different effects in clinical populations in whom baseline brain activity, and excitability might differ from healthy humans. Cathodal tDCS effects, depending on the stimulation intensity and interval, could be affected by respective altered brain physiology. [Extracted from the article]

Abstract: The aim of this study was to determine whether non‐invasive brain stimulation (NIBS) techniques improve fine motor performance in stroke. We searched PubMed, EMBASE, Web of Science, SciELO and OpenGrey for randomized clinical trials on NIBS for fine motor performance in stroke patients and healthy participants. We computed Hedges’ g for active and sham groups, pooled data as random‐effects models and performed sensitivity analysis on chronicity, montage, frequency of stimulation and risk of bias. Twenty‐nine studies (351 patients and 152 healthy subjects) were reviewed. Effect sizes in stroke populations for transcranial direct current stimulation and repeated transcranial magnetic stimulation were 0.31 [95% confidence interval (CI), 0.08–0.55; P = 0.010; Tau2, 0.09; I2, 34%; Q, 18.23; P = 0.110] and 0.46 (95% CI, 0.00–0.92; P = 0.05; Tau2, 0.38; I2, 67%; Q, 30.45; P = 0.007). The effect size of non‐dominant healthy hemisphere transcranial direct current stimulation on non‐dominant hand function was 1.25 (95% CI, 0.09–2.41; P = 0.04; Tau2, 1.26; I2, 93%; Q, 40.27; P < 0.001). Our results show that NIBS is associated with gains in fine motor performance in chronic stroke patients and healthy subjects. This supports the effects of NIBS on motor learning and encourages investigation to optimize their effects in clinical and research settings. [ABSTRACT FROM AUTHOR]

Cognitive functions such as numerical processing and spatial attention show varying degrees of lateralization. Transcranial direct current stimulation (tDCS) can be used to investigate how modulating cortical excitability affects performance of these tasks. This study investigated the effect of bi-parietal tDCS on numerical processing, spatial and sustained attention. It was hypothesized that tDCS would have distinct effects on these tasks because of varying lateralization (numerical processing left, spatial attention right) and that these effects are partly mediated by modulation of sustained attention. A single-blinded, crossover, sham-controlled study was performed. Eighteen healthy right-handed participants performed cognitive tasks during three sessions of oppositional parietal tDCS stimulation: sham; right anodal with left cathodal (RA/LC); and right cathodal with left anodal (RC/LA). Participants performed a number comparison task, a modified Posner task, a choice reaction task (CRT) and the rapid visual processing task (RVP). RA/LC tDCS impaired number comparison performance compared with sham, with slower responses to numerically close numbers pairs. RA/LC and RC/LA tDCS had distinct effects on CRT performance, specifically affecting vigilance level during the final block of the task. No effect of stimulation on the Posner task or RVP was found. It was demonstrated that oppositional parietal tDCS affected both numerical performance and vigilance level in a polarity-dependent manner. The effect of tDCS on numerical processing may partly be due to attentional effects. The behavioural effects of tDCS were specifically observed under high task demands, demonstrating the consequences of an interaction between stimulation type and cognitive load. [ABSTRACT FROM AUTHOR]

Functional neuroimaging studies have shown activation of the supramarginal gyrus during pitch memory tasks. A previous transcranial direct current stimulation study using cathodal stimulation over the left supramarginal gyrus reported a detrimental effect on short-term pitch memory performance, indicating an important role of the supramarginal gyrus in pitch memory. The current study aimed to determine whether pitch memory could be improved following anodal stimulation of the left supramarginal gyrus. The performances of non-musicians on two pitch memory tasks (pitch recognition and recall) and a visual memory control task following anodal or sham transcranial direct current stimulation were compared. The results show that, post-stimulation, the anodal group but not the control group performed significantly better on both pitch memory tasks; performance did not differ on the face memory task. These findings provide strong support for the causal involvement of the left supramarginal gyrus in the pitch memory process, and highlight the potential efficacy of transcranial direct current stimulation as a tool to improve pitch memory. [ABSTRACT FROM AUTHOR]

Input from primary somatosensory cortex (S1) to primary motor cortex (M1) is important for high-level motor performance, motor skill learning and motor recovery after brain lesion. This study tested the effects of manipulating S1 excitability with paired associative transcranial stimulation (S1-PAS) on M1 excitability. Given the important role of S1 in sensorimotor integration, we hypothesized that changes in S1 excitability would be directly paralleled by changes in M1 excitability. We applied two established protocols (S1-PASLTP and S1-PASLTD) to the left S1 to induce long-term potentiation (LTP)-like or long-term depression (LTD)-like plasticity. S1 excitability was assessed by the early cortical components (N20-P25) of the median nerve somatosensory-evoked potential. M1 excitability was assessed by motor-evoked potential amplitude and short-interval intracortical inhibition. Effects of S1-PASLTP were compared with those of a PASLTP protocol targeting the left M1 (M1-PASLTP). S1-PASLTP and S1-PASLTD did not result in significant modifications of S1 or M1 excitability at the group level due to substantial interindividual variability. The individual S1-PAS-induced changes in S1 and M1 excitability showed no correlation. Furthermore, the individual changes in S1 and M1 excitability induced by S1-PASLTP did not correlate with changes in M1 excitability induced by M1-PASLTP. This demonstrates that the effects of S1-PAS in S1 are variable across individuals and, within a given individual, unrelated to those induced by S1-PAS or M1-PAS in M1. Potentially, this extends the opportunities of therapeutic PAS applications because M1-PAS 'non-responders' may well respond to S1-PAS. [ABSTRACT FROM AUTHOR]

Exploring the infinite parameter space: rethinking assumptions underpinning the use of transcranial direct current stimulation to induce long-term effects In addition, by studying two tDCS protocols that differ in both current intensity and length, it is impossible to separate out the effects of these two metrics, both of which have been shown previously to have significant effects on cortical excitability after-effects. Finally, while this is a detailed study of cathodal tDCS in healthy controls, it does not necessarily inform us as to the effects of anodal tDCS and nor does it translate clearly into effects post-stroke. [Extracted from the article]

The article focuses on the research "Aberrant cortical excitability reflects the loss of hand dexterity in musician's dystonia" by S. Furuya and colleagues. Topics discussed include focal task-specific dystonia (FTSD), role of Intracortical inhibition in shaping motor cortex output; and association between abnormalities in cortical function and specific deficits in behaviour among patients with FTSD.

Background and purpose: Progressive non-fluent aphasia (PNFA) is a neurodegenerative disorder that is characterized by non-fluent speech with naming impairment and grammatical errors. It has been recently demonstrated that repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) improves action naming in healthy subjects and in subjects with Alzheimer's disease. Purpose: To investigate whether the modulation of DLPFC circuits by rTMS modifies naming performance in patients with PNFA. Methods: Ten patients with a diagnosis of PNFA were enrolled. High-frequency rTMS was applied to the left and right DLPFC and the sham (i.e. placebo) condition during object and action naming. A subgroup of patients with semantic dementia was enrolled as a comparison group. Results: A repeated-measure anova with stimulus site (sham, left and right rTMS) showed significant effects. Action-naming performances during stimulation of both the left and right DLPFC were better than during placebo stimulation. No facilitating effect of rTMS to the DLPFC on object naming was observed. In patients with a diagnosis of semantic dementia, no effect of stimulation was reported. Conclusions: Our study demonstrated that rTMS improved action naming in subjects with PNFA, possibly due to the modulation of DLPFC pathways and a facilitation effect on lexical retrieval processes. Future studies on the potential of a rehabilitative protocol using rTMS applied to the DLPFC in this orphan disorder are required. [ABSTRACT FROM AUTHOR]