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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].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.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.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].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).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].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].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.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].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].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].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.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).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.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].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].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.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.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].
