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Functional connectivity of the anterior cingulate cortex predicts treatment outcome for rTMS in treatment-resistant depression at 3-month follow-up
Repetitive transcranial magnetic stimulation (rTMS) is a first-line treatment for treatment-resistant depression (TRD). The mechanisms of action of rTMS are not fully understood, and no biomarkers are available to assist in clinical practice to predict response to rTMS. This study aimed to demonstrate that after-rTMS clinical improvement is associated with functional connectivity (FC) changes of the subgenual cingulate cortex (sgACC) and rostral anterior cingulate (rACC), and FC of sgACC and rACC might serve as potential predictors for treatment response.Cortical modulation of nociception by galvanic vestibular stimulation: A potential clinical tool?
Vestibular afferents converge with nociceptive ones within the posterior insula, and can therefore modulate nociception. Consistent with this hypothesis, caloric vestibular stimulation (CVS) has been shown to reduce experimental and clinical pain. Since CVS can induce undesirable effects in a proportion of patients, here we explored an alternative means to activate non-invasively the vestibular pathways using innocuous bi-mastoid galvanic stimulation (GVS), and assessed its effects on experimental pain.A frontal-vagal network theory for Major Depressive Disorder: Implications for optimizing neuromodulation techniques
Major Depressive Disorder (MDD) is a psychiatric disorder characterized by high comorbidity with cardiovascular disease. Furthermore, a combination of high heart rate (HR) and low heart rate variability (HRV) has been frequently reported in depressed patients. The present review proposes a frontal-vagal (brain-heart) network that overlaps with functional nodes of the depression network. Moreover, we summarize neuromodulation studies that have targeted key nodes in this depression network, with subsequent impact on heart rate (HR) or heart-rate-variability (HRV), such as the dorsolateral prefrontal cortex (DLPFC), subgenual anterior cingulate cortex (sgACC), and the vagus nerve (VN).Cardiovascular differences between sham and active iTBS related to treatment response in MDD
Heart rate in MDD is often dysregulated, expressed in overall higher heart rates (HR) and lower heart rate variability (HRV). Interestingly, HR decelerations have been reported after stimulation of the DLPFC using rTMS, suggesting connectivity between the DLPFC and the heart. Recently, a new form of rTMS called theta burst stimulation (TBS) has been developed. One form of TBS, intermittent TBS (iTBS), delivers 600 pulses in just 3 min.Simulation of transcranial magnetic stimulation in head model with morphologically-realistic cortical neurons
Transcranial magnetic stimulation (TMS) enables non-invasive modulation of brain activity with both clinical and research applications, but fundamental questions remain about the neural types and elements TMS activates and how stimulation parameters affect the neural response.Conditions for numerically accurate TMS electric field simulation
Computational simulations of the E-field induced by transcranial magnetic stimulation (TMS) are increasingly used to understand its mechanisms and to inform its administration. However, characterization of the accuracy of the simulation methods and the factors that affect it is lacking.Cost of focality in TDCS: Interindividual variability in electric fields
In transcranial direct current stimulation (TDCS), electric current is applied via two large electrodes to modulate brain activity. Computational models have shown that large electrodes produce diffuse electric fields (EFs) in the brain, which depends on individual head and brain anatomy. Recently, smaller electrodes as well as novel electrode arrangements, including high-definition TDCS (HD-TDCS) montages, have been introduced to improve the focality of EFs. Here, we investigated whether the EFs of focal montages are more susceptible to interindividual anatomical differences.Using EMG to deliver lumbar dynamic electrical stimulation to facilitate cortico-spinal excitability
Potentiation of synaptic activity in spinal networks is reflected in the magnitude of modulation of motor responses evoked by spinal and cortical input. After spinal cord injury, motor evoked responses can be facilitated by pairing cortical and peripheral nerve stimuli.Transcranial direct current stimulation reduces seizure frequency in patients with refractory focal epilepsy: A randomized, double-blind, sham-controlled, and three-arm parallel multicenter study
Transcranial direct current stimulation (tDCS) has been explored in epilepsy with limited samples, varied parameters, and inconclusive results. We aimed to study the efficacy of tDCS for patients with refractory focal epilepsy.Prefrontal delta oscillations during deep brain stimulation predict treatment success in patients with obsessive-compulsive disorder
Deep brain stimulation (DBS) of the ventral capsule/ventral striatum (VC/VS) is a promising neurotherapeutic approach for severe and refractory cases of obsessive-compulsive disorder (OCD). Successful VC/VS-DBS treatment alters function in frontostriatal pathways important for the etiopathogenesis of OCD [1–3]. Monitoring changes in frontostriatal functioning resulting from active DBS can reveal signatures of DBS engagement with disease-relevant pathways [1,4]. In particular, modulation of the dorsal-medial prefrontal cortex (dmPFC) seems to be crucial for therapeutic success: symptomatic OCD patients demonstrate hyperconnectivity between the VC/VS and dmPFC, which is normalized following successful VC/VS-DBS [1,5,6].Transcranial focused ultrasound pulsation suppresses pentylenetetrazol induced epilepsy in vivo
Epilepsy is a neurological disorder characterized by abnormal neuron discharge, and one-third of epilepsy patients suffer from drug-resistant epilepsy (DRE). The current management for DRE includes epileptogenic lesion resection, disconnection, and neuromodulation. Neuromodulation is achieved through invasive electrical stimulus including deep brain stimulation, vagus nerve stimulation, or responsive neurostimulation (RNS). As an alternative therapy, transcranial focused ultrasound (FUS) can transcranially and non-invasively modulate neuron activity.Color perception matches selectivity in human early visual cortex
Where and how the color perception formed in the human brain remains one of the most intriguing topics in vision science. Color selective neurons could be found along the visual hierarchy [1,2], but which level contributes directly to color perception and behaviorally correlated processing is still under debate. Lesion [3] and functional magnetic resonance imaging [4,5] studies in human subjects suggested a group of color-selective areas in the ventral occipitotemporal cortex (VOTC), which labeled V4/V4α or V8, might be critical for color percepts.Dopamine depletion effects on cognitive flexibility as modulated by tDCS of the dlPFC
Recent evidence suggests that transcranial direct current stimulation (tDCS) may interact with the dopaminergic system to affect cognitive flexibility. Objective/hypotheses: We examined whether putative reduction of dopamine levels through the acute phenylalanine/tyrosine depletion (APTD) procedure and excitatory anodal tDCS of the dorsolateral prefrontal cortex (dlPFC) are causally related to cognitive flexibility as measured by task switching and reversal learning.Combination of lithium and electroconvulsive therapy (ECT) is associated with higher odds of delirium and cognitive problems in a large national sample across the United States
Lithium is a helpful adjunct to patients undergoing ECT. However, only case reports and limited data suggest increase risk of delirium. Thus, this continues to be a controversial issue.Super refractory status epilepticus in Lafora disease interrupted by vagus nerve stimulation: A case report
Refractory and super refractory status epilepticus (RSE/SRSE) require effective action to avoid death or serious and irreversible consequences on neurological functions. Regrettably, there is a considerable lack of evidence on the optimal treatment strategy [1]. Vagus nerve stimulation (VNS), an approved chronic therapy for pharmacoresistant epilepsy, was initiated acutely in less than 40 reported patients with RSE/SRSE, interrupting 74% of cases [2]. However, several studies failed to provide adequate information on patient clinical characteristics, concomitant and previous treatments, stimulation protocols and data on long-term prognosis [2].God locked you in the room, but left a window open: A case report of spinal cord stimulation in locked-in syndrome
Locked-in syndrome (LIS), caused by severe damage to the pons, is a serious neurological condition of movement deficiency, characterized by quadriplegia and aphonia. Spinal cord stimulation (SCS), the most common neuromodulation therapy, has recently been shown to restore walking in patients with spinal cord injury [1]. The possibility of SCS treatment in LIS is still unclear. We reported the first application of cervical SCS in a classic LIS patient with encouraging outcomes.Quantifying acute physiological biomarkers of transcutaneous cervical vagal nerve stimulation in the context of psychological stress
Stress is associated with activation of the sympathetic nervous system, and can lead to lasting alterations in autonomic function and in extreme cases symptoms of posttraumatic stress disorder (PTSD). Vagal nerve stimulation (VNS) is a potentially useful tool as a modulator of autonomic nervous system function, however currently available implantable devices are limited by cost and inconvenience.Adaptive current tDCS up to 4 mA
Higher tDCS current may putatively enhance efficacy, with tolerability the perceived limiting factor.A new device to improve target localization for transcranial magnetic stimulation therapy
Accurate identification of cranial midline structures is essential for many targeting techniques that use repetitive transcranial magnetic stimulation (rTMS), including the Beam F3 method used for depression treatment.Cortical inhibition in major depression: Investigating the acute effect of single-session yoga versus walking
While the etiology of depressive disorders is multifactorial, spanning diverse polygenic origins and environmental exposures, its impact on an aberrant cortical inhibition-excitation balance is one of the final common pathophysiological processes [1–3]. Gamma-aminobutyric acid (GABA) – an abundant inhibitory neurotransmitter in the nervous system, along with glutamate – an excitatory neurotransmitter, is vital in maintaining an optimal balance required for healthy brain functions. One of the contributing factors to the cortical excitation-inhibition imbalance in depression is GABAergic dysfunction [4].Direct current stimulation-induced synaptic plasticity in the sensorimotor cortex: structure follows function
Non-invasive direct current stimulation (DCS) of the brain induces functional plasticity in vitro and facilitates motor learning across species. The effect of DCS on structural synaptic plasticity is currently unknown.Safety of transcranial focused ultrasound stimulation: A systematic review of the state of knowledge from both human and animal studies
Low-intensity transcranial focused ultrasound stimulation (TFUS) holds great promise as a highly focal technique for transcranial stimulation even for deep brain areas. Yet, knowledge about the safety of this novel technique is still limited.Cerebellar rTMS for motor control in progressive supranuclear palsy
Stimulatory cerebellar TMS is a promising tool to improve motor control in neurodegenerative disorders. Objective/hypothesis: Our goal was to use 10Hz cerebellar rTMS to augment cerebellar-brain inhibition (CBI) for improved postural stability and speech in patients with progressive supranuclear palsy (PSP).The relationship between individual alpha peak frequency and clinical outcome with repetitive Transcranial Magnetic Stimulation (rTMS) treatment of Major Depressive Disorder (MDD)
The individual α frequency (IAF) has been associated with the outcome of repetitive Transcranial Magnetic Stimulation (rTMS) treatment of Major Depressive Disorder (MDD), but the association has been inconsistent.The effects of repetitive transcranial magnetic stimulation on body weight and food consumption in obese adults: A randomized controlled study
Although some studies have reported significant reductions in food cravings following the single-session of repetitive transcranial magnetic stimulation (rTMS), there is little research on the effects of multi-session of rTMS on food consumption and body weight in obese subjects.Reversible neuroinhibition by focused ultrasound is mediated by a thermal mechanism
Transcranial focused ultrasound (tFUS) at low intensities has been reported to directly evoke responses and reversibly inhibit function in the central nervous system. While some doubt has been cast on the ability of ultrasound to directly evoke neuronal responses, spatially-restricted transcranial ultrasound has demonstrated consistent, inhibitory effects, but the underlying mechanism of reversible suppression in the central nervous system is not well understood.Characterizing and minimizing the contribution of sensory inputs to TMS-evoked potentials
Transcranial magnetic stimulation (TMS) evokes voltage deflections in electroencephalographic (EEG) recordings, known as TMS-evoked potentials (TEPs), which are increasingly used to study brain dynamics. However, the extent to which TEPs reflect activity directly evoked by magnetic rather than sensory stimulation is unclear.Impact of prior treatment on remission with intermittent theta burst versus high-frequency repetitive transcranial magnetic stimulation in treatment resistant depression
Multiple prior treatment failures are associated with reduced rates of remission to subsequent antidepressant treatment, including rTMS. The degree of treatment resistance that is especially predictive of inferior outcome is uncertain. Intermittent theta burst stimulation (iTBS) is a newer form of rTMS where less is known regarding clinical predictors of remission. The THREE-D study demonstrated that iTBS is non-inferior to 10 Hz rTMS for the treatment of depression.Investigating the effects of transcranial direct current stimulation on obstacle negotiation performance in Parkinson disease with freezing of gait: A pilot study
Freezing of gait (FOG) is a severe symptom associated with Parkinson's disease (PD) which often occurs during complex walking, such as stepping over an obstacle in the ground, or while performing a secondary task [1]. To date, FOG poorly responds to pharmacological interventions and hardly affects daily life activities, thus the development of innovative treatments is needed. In this context, transcranial direct current stimulation (tDCS) has been studied as a non-pharmacological option [2–4]. Indeed, multiple sessions of tDCS over M1 were able to decrease number and duration of FOG episodes [4].Theoretical principles of deep brain stimulation induced synaptic suppression
Deep brain stimulation (DBS) is a successful clinical therapy for a wide range of neurological disorders; however, the physiological mechanisms of DBS remain unresolved. While many different hypotheses currently exist, our analyses suggest that high frequency (∼100 Hz) stimulation-induced synaptic suppression represents the most basic concept that can be directly reconciled with experimental recordings of spiking activity in neurons that are being driven by DBS inputs.MR imaging central thalamic deep brain stimulation restored autistic-like social deficits in the rat
Social deficit is a core symptom in autism spectrum disorder (ASD). Although deep brain stimulation (DBS) has been proposed as a potential treatment for ASD, an ideal target nucleus is yet to be identified. DBS at the central thalamic nucleus (CTN) is known to alter corticostriatal and limbic circuits, and subsequently increase the exploratory motor behaviors, cognitive performance, and skill learning in neuropsychiatric and neurodegenerative disorders.Frequency-specific effects of low-intensity rTMS can persist for up to 2 weeks post-stimulation: A longitudinal rs-fMRI/MRS study in rats
Evidence suggests that repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, alters resting brain activity. Despite anecdotal evidence that rTMS effects wear off, there are no reports of longitudinal studies, even in humans, mapping the therapeutic duration of rTMS effects.LTD-like plasticity of the human primary motor cortex can be reversed by γ-tACS
Cortical oscillatory activities play a role in regulating several brain functions in humans. However, whether motor resonant oscillations (i.e. β and γ) modulate long-term depression (LTD)-like plasticity of the primary motor cortex (M1) is still unclear.Corrigendum to “Analytical bias accounts for some of the reported effects of tACS on auditory perception” [Brain Stimul. 12 (4) (2019) 1001–1009]
In the calculation of the Bayesian information criterion (BIC) in this publication we inadvertently swapped the variables n and k in the text as well as in the published code (SimWilsch2018.m) which was used to calculate and plot (Fig. 3B) the BIC.MEG and navigated TMS jointly enable spatially accurate application of TMS therapy at the epileptic focus in pharmacoresistant epilepsy
Pharmacoresistant epilepsy is associated with increased morbidity, mortality and a reduced quality of life for patients [1]. Several neurostimulation techniques have been evaluated for pharmacoresistant epilepsy including repetitive transcranial magnetic stimulation (rTMS). At present, the efficacy of rTMS as a therapeutic alternative remains uncertain [2]. We studied three patients with refractory focal epilepsy. The seizure onset zone (SOZ) was estimated using a combination of seizure semiology, electroclinical findings, MRI imaging and magnetoencephalography (MEG).A single session of bihemispheric transcranial direct current stimulation does not improve quadriceps muscle spasticity in people with chronic stroke
Cerebral lesions following stroke cause an interhemispheric competition in the brain where the excitability of the affected hemisphere decreases and that of the unaffected hemisphere increases. This leads to a reduction of inhibitory control of spinal networks by the corticospinal tract of the affected side which in turn lead to the phenomenon of spasticity [1]. It has been found that i) bihemispheric-transcranial direct current stimulation (bi-tDCS) may reduce the interhemispheric imbalance in chronic stroke people (CSP) [2], and ii) anodal-tDCS applied over the affected leg motor cortex can alter the excitability of some spinal circuits involved in spasticity [3].Safety, tolerability and effectiveness of a novel 20 Hz rTMS protocol targeting dorsomedial prefrontal cortex in major depression: An open-label case series
Repetitive transcranial magnetic stimulation (rTMS) of the dorsomedial prefrontal cortex (DMPFC) in treatment-resistant depression (TRD) has been recently studied as an alternative to conventional dorsolateral prefrontal cortex (DLPFC) rTMS [1,2]. Across both targets, intermittent theta-burst stimulation (iTBS) reduces treatment duration while achieving comparable outcomes to conventional 10 Hz stimulation [1,3]. However, iTBS can require more costly devices than conventional high-frequency rTMS, and the consistency of excitatory effect varies across individuals [4].After-effects of 10 Hz tACS over the prefrontal cortex on phonological word decisions
Previous work in the language domain has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (pIFG) in the prefrontal cortex impaired phonological decision-making, arguing for a causal contribution of the bilateral pIFG to phonological processing. However, the neurophysiological correlates of these effects are unclear. The present study addressed the question whether neural activity in the prefrontal cortex could be modulated by 10 Hz tACS and how this would affect phonological decisions.Transcranial direct current stimulation (tDCS) for depression in pregnancy: A pilot randomized controlled trial
Depression in pregnancy negatively affects maternal-child health. Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation treatment for depression, has not been evaluated in pregnancy.Real-time estimation of electric fields induced by transcranial magnetic stimulation with deep neural networks
Transcranial magnetic stimulation (TMS) plays an important role in treatment of mental and neurological illnesses, and neurosurgery. However, it is difficult to target specific brain regions accurately because the complex anatomy of the brain substantially affects the shape and strength of the electric fields induced by the TMS coil. A volume conductor model can be used for determining the accurate electric fields; however, the construction of subject-specific anatomical head structures is time-consuming.Prestimulus cortical EEG oscillations can predict the excitability of the primary motor cortex
The motor evoked potentials (MEPs) elicited by single-pulse transcranial magnetic stimulation (TMS) vary considerably at rest, but the mechanism underlying this amplitude variation is largely unknown. We hypothesized that prestimulus EEG oscillations modulate the subsequent MEPs in a state-dependent manner.Cortico-spinal tDCS in ALS: A randomized, double-blind, sham-controlled trial
Amyotrophic lateral sclerosis (ALS) is a progressive disease which affects both upper and lower motor neurons, with a fatal prognosis, for which no curative treatment is currently available. Glutamate-driven excitotoxicity is supposed to be involved in its pathophysiology, and drugs such as riluzole or edaravone have shown to reduce disease progression in ALS to a limited extent.Modulation of creativity by transcranial direct current stimulation
Creativity is the use of original ideas to accomplish something innovative. Previous research supports the notion that creativity is facilitated by an activation of the right and/or a deactivation of the left prefrontal cortex. In contrast, recent brain imaging studies suggest that creativity improves with left frontal activation.The role of the dorsal anterior insula in ecstatic sensation revealed by direct electrical brain stimulation
An ecstatic phenomenon is an altered state of consciousness with a sense of “hyper-reality”, and a complete present-moment awareness with a feeling of union with the Universe. A better understanding of the network mechanisms underlying this fascinating subjective experience may help to unravel some mysteries of human consciousness. Insula has been recently proposed to be a key region to elicit these symptoms.tDCS to the left DLPFC modulates cognitive and physiological correlates of executive function in a state-dependent manner
The use of transcranial Direct Current Stimulation (tDCS) to study anatomical and physiological dynamics and circuits supporting cognition and executive functions in particular has dramatically increased in recent years. However, its mechanisms of action remain only partially understood.Effects of 6-month at-home transcranial direct current stimulation on cognition and cerebral glucose metabolism in Alzheimer's disease
Although single or multiple sessions of transcranial direct current stimulation (tDCS) on the prefrontal cortex over a few weeks improved cognition in patients with Alzheimer's disease (AD), effects of repeated tDCS over longer period and underlying neural correlates remain to be elucidated.The effect of electroconvulsive therapy (ECT) on serum tryptophan metabolites
Prior studies suggest that activation of the tryptophan catabolism via the kynurenine pathway by proinflammatory cytokines may be involved in the pathophysiology of depression. Electroconvulsive therapy (ECT) is an effective treatment for major depression (MD) with immunomodulation as one of the proposed modes of action.Stimulation over the cerebellum with a regular figure-of-eight coil induces reduced motor cortex inhibition in patients with progressive supranuclear palsy
To determine whether motor cortex inhibition by stimulation over the cerebellum with a figure-of eight coil (MISC8) may be reduced in patients with Progressive Supranuclear Palsy (PSP).Combining reward and M1 transcranial direct current stimulation enhances the retention of newly learnt sensorimotor mappings
Reward-based feedback given during motor learning has been shown to improve the retention of the behaviour being acquired. Interestingly, applying transcranial direct current stimulation (tDCS) during learning over the primary motor cortex (M1), an area associated with motor retention, also results in enhanced retention of the newly formed motor memories. However, it remains unknown whether combining these distinct interventions result in an additive benefit of motor retention.No additive meta plasticity effects of accelerated iTBS with short inter-session intervals
Many studies have aimed to optimize repetitive transcranial magnetic (rTMS) protocols, focusing on shortening protocol length, increasing plasticity effect size, and decreasing variability. The Theta Burst protocols (TBS) for example require only minutes of application duration and reportedly induce less variable and longer lasting plasticity effects compared to classic rTMS protocols [1]. Intermittent TBS (iTBS) is a 3-min protocol, which has been shown to increase cortical excitability for up to 1-h post stimulation [1].Directional stimulation of subthalamic nucleus sweet spot predicts clinical efficacy: Proof of concept
Directional deep brain stimulation (dDBS) of the subthalamic nucleus for Parkinson's disease (PD) increases the therapeutic window. However, empirical programming of the neurostimulator becomes more complex given the increasing number of stimulation parameters. A better understanding of dDBS is needed to improve therapy and help guide postoperative programming.A fast and general method to empirically estimate the complexity of brain responses to transcranial and intracranial stimulations
The Perturbational Complexity Index (PCI) was recently introduced to assess the capacity of thalamocortical circuits to engage in complex patterns of causal interactions. While showing high accuracy in detecting consciousness in brain-injured patients, PCI depends on elaborate experimental setups and offline processing, and has restricted applicability to other types of brain signals beyond transcranial magnetic stimulation and high-density EEG (TMS/hd-EEG) recordings.The influence of endogenous estrogen on high-frequency prefrontal transcranial magnetic stimulation
The use of repetitive transcranial magnetic stimulation (rTMS) as both therapeutic and experimental tools has grown enormously over the past decade. However, variability in response to rTMS is one challenge that remains to be solved. Estrogen can impact neural plasticity and may also affect plastic changes following rTMS. The present study investigated whether estrogen levels influence the neurophysiological effects of high-frequency (HF) rTMS in the left dorsolateral prefrontal cortex (DLPFC).Habenula deep brain stimulation for refractory bipolar disorder
Bipolar disorder (BD) is a mood disorder associated with significant morbidity and mortality. In many cases, BD can be managed with pharmacotherapy, psychological therapy, or electroconvulsive therapy [1]. For some afflicted patients, however, BD is a chronic and severely disabling condition that is resistant to the aforementioned treatments. Deep brain stimulation (DBS) offers a safe and effective neurosurgical treatment for otherwise refractory movement disorders and obsessive-compulsive disorder [2,3].No trace of phase: Corticomotor excitability is not tuned by phase of pericentral mu-rhythm
The motor potentials evoked by transcranial magnetic stimulation (TMS) over the motor hand area (M1-HAND) show substantial inter-trial variability. Pericentral mu-rhythm oscillations, might contribute to inter-trial variability. Recent studies targeting mu-activity based on real-time electroencephalography (EEG) reported an influence of mu-power and mu-phase on the amplitude of motor evoked potentials (MEPs) in a preselected group with strong pericentral mu-activity. Other studies that determined mu-power or mu-phase based on post-hoc trial sorting according in non-preselected individuals were largely negative.Antidepressant effects of tDCS are associated with prefrontal gray matter volumes at baseline: Evidence from the ELECT-TDCS trial
Transcranial direct current stimulation (tDCS) is a promising intervention for major depression. However, its clinical effects are heterogeneous. We investigated, in a subsample of the randomized, clinical trial Escitalopram versus Electrical Direct Current Therapy for Depression Study (ELECT-TDCS), whether the volumes of left and right prefrontal cortex (PFC) and anterior cingulate cortex (ACC) were associated with prefrontal tDCS response.Cardiovascular autonomic effects of transcutaneous auricular nerve stimulation via the tragus in the rat involve spinal cervical sensory afferent pathways
Electrical stimulation on select areas of the external auricular dermatome influences the autonomic nervous system. It has been postulated that activation of the Auricular Branch of the Vagus Nerve (ABVN) mediates such autonomic changes. However, the underlying neural pathways mediating these effects are unknown and, further, our understanding of the anatomical distribution of the ABVN in the auricle has now been questioned.Contextual cues as modifiers of cTBS effects on indulgent eating
Prior studies have found that continuous theta burst stimulation (cTBS) targeting the left dlPFC results in reliable increases in consumption of calorie-dense food items. However, it is not known to what extent such effects are modified by cues in the immediate eating environment. Tempting environments (i.e., those saturated with appetitive eating cues) may lead to more reliance on cognitive control networks involving the dlPFC, thereby enhancing cTBS effects on indulgent eating.Modulation of large-scale cortical coupling by transcranial alternating current stimulation
Long-range functional connectivity in the brain is considered fundamental for cognition and is known to be altered in many neuropsychiatric disorders. To modify such coupling independent of sensory input, noninvasive brain stimulation could be of utmost value.Focused ultrasound-induced blood brain-barrier opening enhanced vascular permeability for GDNF delivery in Huntington's disease mouse model
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the gene encoding the huntingtin (Htt) protein, which results in a protein containing an abnormally expanded polyglutamine (polyQ) sequence. The expanded polyQ in the Htt protein is toxic to brain cells. No therapy exists to delay disease progression.Combining electrical stimulation and cognitive control training to reduce concerns about subjective cognitive decline
Subjective cognitive decline (SCD) is characterized by a self-perceived deterioration of cognitive abilities in the absence of objective deficits or depression [1]. Concerns associated with SCD are increasingly acknowledged as risk factor for the development of Alzheimer's disease (AD) [1,2] and often affect psychological well-being [3].Somatosensory-motor cortex interactions measured using dual-site transcranial magnetic stimulation
Dual-site transcranial magnetic stimulation (ds-TMS) is a neurophysiological technique to measure functional connectivity between cortical areas.Effects of cerebellar transcranial direct current stimulation on cerebellar-brain inhibition in humans: A systematic evaluation
Cerebellar transcranial direct current stimulation (ctDCS) is increasingly used to modulate cerebellar excitability and plasticity in healthy subjects and various patient populations. ctDCS parameters are poorly standardized, and its physiology remains little understood. Our aim was to compare the physiological effects of three different non-target electrode positions (buccinator muscle, supraorbital region, deltoid muscle).High intensity aerobic exercise does not prime the brain for anodal transcranial direct current stimulation
The benefits of both regular and acute exercise on cognitive function are well-established. One candidate mechanism is the increase in brain derived neurotropic factor (BDNF), which is involved in exercise-induced neuroplasticity [1]. An increase in serum BDNF after a single exercise session may create favourable conditions for adaptive plasticity [2], and has also been shown to influence anodal transcranial direct current stimulation (a-tDCS) in mice [3]. We investigated the acute effects of a single bout of high-intensity interval training (HIIT) performed prior to dorsolateral pre-frontal cortex (DLPFC) a-tDCS on cognitive performance, serum BDNF, and the cerebral haemodynamic response in healthy adults.Adverse events associated with deep brain stimulation in patients with childhood-onset dystonia
Data on pediatric DBS is still limited because of small numbers in single center series and lack of systematic multi-center trials.Long-term effects of subthalamic stimulation in Obsessive-Compulsive Disorder: Follow-up of a randomized controlled trial
Obsessive-Compulsive Disorder (OCD) is characterized by intrusive, anxious thoughts with repetitive, ritualized behaviors, and has negative impacts on family relationships and social life. Its lifetime prevalence is estimated to be 2–3% [1]. Cognitive and behavioral therapy and selective serotonin reuptake inhibitors are the standard treatments for OCD; nevertheless, despite these treatments, between 25 and 40% of patients display persistent symptoms leading to severe functional disability [2]. Neurosurgical treatment targeting different parts of the orbito-fronto-striato-thalamo-cortical circuit has been proposed for the most severe and refractory forms, including both gamma knife non-invasive stereotactic lesions and invasive deep brain stimulation (DBS) [3] (Supplementary Information).Distilling the essence of TMS-evoked EEG potentials (TEPs): A call for securing mechanistic specificity and experimental rigor
Using realistic sham stimulation, we have shown that transcranial magnetic stimulation (TMS) produces significant off-target excitation of the peripheral nervous system, even when applying state-of-the-art procedures to attenuate peripheral co-activation [1]. The peripherally evoked potentials (PEPs) strongly resembled TMS-evoked potentials (TEPs) [1]. Our study prompted a letter to the editor in the Brain Stimulation journal, signed by many researchers using TEP recordings [2]. While Belardinelli et al.Sacral nerve stimulation improves gait in Parkinson's disease
Neurogenic overactive bladder is frequently present as a manifestation of autonomic dysfunction in patients with Parkinson's disease (PD). Sacral nerve stimulation (SNS), which delivers low-amplitude electrical stimulation via a lead to the sacral nerve accessed from the S3 foramen, is an established treatment of urinary incontinence, high urinary frequency and urinary retention [1]. Here, we report our findings that SNS unexpectedly improved gait in a patient with PD.Towards precise brain stimulation: Is electric field simulation related to neuromodulation?
Recent research on neural and behavioral consequences of transcranial direct current stimulation (tDCS) has highlighted the impact of individual factors, such as brain anatomy which determines current field distribution and may thus significantly impact stimulation effects. Computational modeling approaches may significantly advance our understanding of such factors, but the association of simulation-based tDCS-induced fields and neurophysiological outcomes has not been investigated.Transcranial direct current stimulation for unipolar depression and risk of treatment emergent mania: An updated meta-analysis
As transcranial direct current stimulation (tDCS) emerges as an investigational noninvasive approach for the treatment of major depressive disorder, there is increasing interest in its safety profile [1]. Several studies and case reports suggest that tDCS may be associated with increased risk of treatment-emergent mania or hypomania (TEM) when used to treat depression [2–4]. In 2017, Brunoni et al. [3] conducted a meta-analysis of TEM in ten randomized controlled trials (RCTs) evaluating antidepressant effects of active tDCS (n = 226) and sham tDCS (n = 190) in unipolar and bipolar depression and failed to demonstrate group differences [3].Analytical bias accounts for some of the reported effects of tACS on auditory perception
Transcranial alternating current stimulation (tACS) has been shown to modulate auditory, visual, cognitive and motor function. However, tACS effects can often be small and difficult to reproduce. Thus, the establishment of robust experimental and analysis procedures is of high importance. We reviewed the analysis used in six studies that investigated if tACS can phase-modulate auditory perception. All studies used analytical methods that introduce bias and could produce false positive results. Four studies corrected for this bias but two did not.Individual differences in TMS sensitivity influence the efficacy of tDCS in facilitating sensorimotor adaptation
Transcranial direct current stimulation (tDCS) can enhance cognitive function in healthy individuals, with promising applications as a therapeutic intervention. Despite this potential, variability in the efficacy of tDCS has been a considerable concern.Consistent linear and non-linear responses to invasive electrical brain stimulation across individuals and primate species with implanted electrodes
Electrical neuromodulation via implanted electrodes is used in treating numerous neurological disorders, yet our knowledge of how different brain regions respond to varying stimulation parameters is sparse.Is awake physiological confirmation necessary for DBS treatment of Parkinson's disease today? A comparison of intraoperative imaging, physiology, and physiology imaging-guided DBS in the past decade
Deep brain stimulation (DBS) is a well-established surgical therapy for Parkinson's disease (PD). Intraoperative imaging (IMG), intraoperative physiology (PHY) and their combination (COMB) are the three mainstream DBS guidance methods.Elimination of peripheral auditory pathway activation does not affect motor responses from ultrasound neuromodulation
Recent studies in a variety of animal models including rodents, monkeys, and humans suggest that transcranial focused ultrasound (tFUS) has considerable promise for non-invasively modulating neural activity with the ability to target deep brain structures. However, concerns have been raised that motor responses evoked by tFUS may be due to indirect activation of the auditory pathway rather than direct activation of motor circuits.Transcranial direct current stimulation in inflammatory bowel disease patients modifies resting-state functional connectivity: A RCT
Chronic pain is known to be associated with functional and structural changes in the brain. Inflammatory bowel disease (IBD) presents with chronic abdominal pain in almost 35% of all patients. This study investigates structural and functional changes in magnetic resonance imaging (MRI) after transcranial direct current stimulation (tDCS) applied to ameliorate pain in IBD.Significant improvement in treatment resistant auditory verbal hallucinations after 5 days of double-blind, randomized, sham controlled, fronto-temporal, transcranial direct current stimulation (tDCS): A replication/extension study
Transcranial direct current stimulation (tDCS) is a potentially novel treatment for antipsychotic-resistant auditory verbal hallucinations (AVH) in schizophrenia. Nevertheless, results have been mixed across studies.Letter to the editor: Thalamic deep brain stimulation may relieve breathlessness in COPD
The cerebral mechanisms of dyspnoea (breathlessness) are not well understood. Neuroimaging studies of experimentally induced dyspnoea in healthy individuals have identified several cortical areas that might form a neural network for perception of dyspnoea [1], much like those identified for pain perception [2]. However, functional imaging studies alone do not reveal neurophysiological pathways and may miss putative targets for dyspnoea relief. The objective of this study was to assess the effects of Deep Brain Stimulation (DBS) of four different brain nuclei on the sensation of dyspnoea in an individual with Chronic Obstructive Pulmonary Disease (COPD) using an established multidimensional dyspnoea tool [3].Somatosensory and transcranial direct current stimulation effects on manual dexterity and motor cortex function: A metaplasticity study
Non-invasive neuromodulation may provide treatment strategies for neurological deficits affecting movement, such as stroke. For example, weak electrical stimulation applied to the hand by wearing a “mesh glove” (MGS) can transiently increase primary motor cortex (M1) excitability. Conversely, transcranial direct current stimulation with the cathode over M1 (c-tDCS) can decrease corticomotor excitability. Objective/Hypothesis: We applied M1 c-tDCS as a priming adjuvant to MGS and hypothesised metaplastic effects would be apparent in improved motor performance and modulation of M1 inhibitory and facilitatory circuits.TMS-EEG approach unveils brain mechanisms underlying conscious and unconscious face perception
Conscious perception of external stimuli has been related to recurrent activity in distributed cortical networks, although brain mechanisms controlling unconscious processing and stimuli access to conscious report need to be clarified.Dual threshold neural closed loop deep brain stimulation in Parkinson disease patients
Closed loop deep brain stimulation (clDBS) in Parkinson's disease (PD) using subthalamic (STN) neural feedback has been shown to be efficacious only in the acute post-operative setting, using externalized leads and stimulators.Decreasing battery life in subthalamic deep brain stimulation for Parkinson's disease with repeated replacements: Just a matter of energy delivered?
People with Parkinson's disease (PD) treated with deep brain stimulation (DBS) with non-rechargeable implantable pulse generators (IPGs) require elective IPG replacement operations involving surgical and anesthesiologic risk. Life expectancy and the number of replacements per patient with DBS are increasing.Slow oscillatory transcranial direct current stimulation (so-tDCS) during slow wave sleep has no effects on declarative memory in healthy young subjects
The manipulation of specific brain oscillations by applying transcranial electrical stimulation techniques in order to enhance memory processes during sleep has become an intriguing field of research. A seminal study found a positive effect of slow-oscillatory transcranial direct current stimulation (so-tDCS) on sleep-dependent consolidation of declarative memories. Since then several studies have tried to replicate this result with inconsistent findings.Photobiomodulation in Parkinson's disease: A randomized controlled trial
Photobiomodulation, which uses non-thermal and non-ionizing light in the visible and infrared spectrum, has been proposed as a potential strategy for improving the symptoms of patients with Parkinson's disease (PD) [1], but this has not been tested in a randomized controlled trial (RCT). We thus sought to assess whether photobiomodulation can ameliorate the cardinal motor symptoms of PD using an RCT design.Decoding voluntary movements and postural tremor based on thalamic LFPs as a basis for closed-loop stimulation for essential tremor
High frequency Deep brain stimulation (DBS) targeting motor thalamus is an effective therapy for essential tremor (ET). However, conventional continuous stimulation may deliver unnecessary current to the brain since tremor mainly affects voluntary movements and sustained postures in ET.Increased perseverative errors following high-definition transcranial direct current stimulation over the ventrolateral cortex during probabilistic reversal learning
The prefrontal cortex regulates behavioural adaptation in response to feedback. However, the causal role of different prefrontal regions remains unclear, based on indirect evidence derived from functional neuroimaging. Neuroimaging studies show dorsomedial prefrontal activation during feedback monitoring, whereas the ventrolateral prefrontal cortex engages during behavioural adaptation (shifting).The influence of respiration on brainstem and cardiovagal response to auricular vagus nerve stimulation: A multimodal ultrahigh-field (7T) fMRI study
Brainstem-focused mechanisms supporting transcutaneous auricular VNS (taVNS) effects are not well understood, particularly in humans. We employed ultrahigh field (7T) fMRI and evaluated the influence of respiratory phase for optimal targeting, applying our respiratory-gated auricular vagal afferent nerve stimulation (RAVANS) technique.No evidence for modulation of outer hair-cell function by 4-Hz transcranial alternating current stimulation
A growing number of studies show that transcranial stimulation with direct current (TDCS) or alternating current (TACS) applied above the auditory cortex can alter auditory cognition (for reviews, see Refs. [1–3]). These auditory effects are often interpreted as being mediated by neural excitability changes under the temporal electrodes and as reflecting a causal role of auditory cortex in the studied auditory phenomenon. A widely neglected alternative is to attribute this causal role, partially or fully, to neuronal structures belonging to earlier stages of the auditory stimulus processing hierarchy.Psychogenic non-epileptic seizures treated with guided transcranial direct current stimulation: A case report
We report the case of a 39-year-old women presenting with psychogenic non-epileptic seizures, who was successfully treated with neuro-guided transcranial direct current stimulation.Chronic brain stimulation rewarding experience ameliorates depression-induced cognitive deficits and restores aberrant plasticity in the prefrontal cortex
Major depressive disorder (MDD) is a multifactorial disease which often coexists with cognitive deficits. Depression-induced cognitive deficits are known to be associated with aberrant reward processing, neurochemical and structural alterations. Recent studies have shown that chronic electrical stimulation of brain reward areas induces a robust antidepressant effect. However, the effects of repeated electrical self-stimulation of lateral hypothalamus - medial forebrain bundle (LH-MFB) on depression-induced cognitive deficits and associated neurochemical and structural alterations in the prefrontal cortex (PFC) are unknown.Transcutaneous spinal direct current stimulation improves locomotor learning in healthy humans
Ambulation is an essential aspect of daily living and is often impaired after brain and spinal cord injuries. Despite the implementation of standard neurorehabilitative care, locomotor recovery is often incomplete.Direction of TDCS current flow in human sensorimotor cortex influences behavioural learning
Recent studies have shown that neurophysiological outcomes of transcranial direct current stimulation (TDCS) are influenced by current flow in brain regions between the electrodes, and in particular the orientation of current flow relative to the cortical surface.Reproducibility in TMS–EEG studies: A call for data sharing, standard procedures and effective experimental control
A recent study by Conde, Tomasevic et al. (2019) [1] puts a spotlight on the subtleties of experimental design and analysis of studies involving TMS-evoked EEG potentials (TEPs), specifically focusing on the challenge of disentangling genuine cortical responses to TMS from those resulting from concomitant sensory activation. This is a relevant topic that the TMS–EEG community has previously identified [2] and addressed with different strategies [3–6]. Based on the similarity of the evoked EEG responses they obtained in real TMS at different sites and in sham conditions (auditory and somatosensory scalp stimulation), the authors of [1] inferred that TEPs can be significantly contaminated by the effects of concurrent, non-transcranial stimulation.Dual-site high-density 4Hz transcranial alternating current stimulation applied over auditory and motor cortical speech areas does not influence auditory-motor mapping
Learning to speak and speaking require the continuous mapping of speech sounds onto articulatory motor plans (auditory-motor mapping). Previous studies using various techniques (histology, lesion mapping, diffusion tensor-imaging, and transcranial magnetic stimulation) have provided converging evidence for the relevance of a dorsal cortical processing stream, including auditory and motor areas, for auditory-motor mapping [1–4].Medial septal stimulation increases seizure threshold and improves cognition in epileptic rats
Temporal lobe epilepsy is most prevalent among focal epilepsies, and nearly one-third of patients are refractory to pharmacological intervention. Persistent cognitive and neurobehavioral comorbidities also occur due to the recurrent nature of seizures and medication-related side effects.Publication trends in transcranial magnetic stimulation: a 30-year panorama
Transcranial magnetic stimulation (TMS) is a non-invasive neuromodulatory technique that has broad diagnostic and therapeutic potential across a range of neurological and psychiatric diseases.Differential effects of bifrontal tDCS on arousal and sleep duration in insomnia patients and healthy controls
Arousal and sleep represent basic domains of behavior, and alterations are of high clinical importance.The effect of electroconvulsive therapy on cerebral monoamine oxidase A expression in treatment-resistant depression investigated using positron emission tomography
Electroconvulsive therapy (ECT) constitutes one of the most effective antidepressant treatment strategies in major depression (MDD). Despite its common use and uncontested efficacy, its mechanism of action is still insufficiently understood. Previously, we showed that ECT is accompanied by a global decrease of serotonin-1A receptors in MDD; however, further studies to investigate the involvement of the serotonergic system in the mechanism of action of ECT are warranted. The monoamine oxidase A (MAO-A) represents an important target for antidepressant treatments and was found to be increased in MDD.Sham tDCS: A hidden source of variability? Reflections for further blinded, controlled trials
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique increasingly used to modulate neural activity in the living brain. In order to establish the neurophysiological, cognitive or clinical effects of tDCS, most studies compare the effects of active tDCS to those observed with a sham tDCS intervention. In most cases, sham tDCS consists in delivering an active stimulation for a few seconds to mimic the sensations observed with active tDCS and keep participants blind to the intervention.Effects of single-session versus multi-session non-invasive brain stimulation on craving and consumption in individuals with drug addiction, eating disorders or obesity: A meta-analysis
Brain stimulation interventions are increasingly used to reduce craving and consumption in individuals with drug addiction or excessive eating behavior. However, the efficacy of these novel treatments and whether effect sizes are affected by the length of the intervention has not been comprehensively evaluated.
