27,081 results match your criteria direct cortical

Conveyance of cortical pacing for parkinsonian tremor-like hyperkinetic behavior by subthalamic dysrhythmia.

Cell Rep 2021 Apr;35(3):109007

Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; Neuroscience Research Center, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan 333, Taiwan. Electronic address:

Parkinson's disease is characterized by both hypokinetic and hyperkinetic symptoms. While increased subthalamic burst discharges have a direct causal relationship with the hypokinetic manifestations (e.g. Read More

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Cortical haemodynamic response during the verbal fluency task in patients with bipolar disorder and borderline personality disorder: a preliminary functional near-infrared spectroscopy study.

BMC Psychiatry 2021 Apr 20;21(1):201. Epub 2021 Apr 20.

Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore, 117599, Singapore.

Background: Functional near-infrared spectroscopy (fNIRS) is an emerging neuroimaging modality that provides a direct and quantitative assessment of cortical haemodynamic response during a cognitive task. It may be used to identify neurophysiological differences between psychiatric disorders with overlapping symptoms, such as bipolar disorder (BD) and borderline personality disorder (BPD). Hence, this preliminary study aimed to compare the cerebral haemodynamic function of healthy controls (HC), patients with BD and patients with BPD. Read More

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Interocular Grouping in Perceptual Rivalry Localized with fMRI.

Brain Topogr 2021 Apr 19. Epub 2021 Apr 19.

Department of Ophthalmology, McGill University, Montreal, QC, H9G 1A4, Canada.

Bistable perception refers to a broad class of dynamically alternating visual illusions that result from ambiguous images. These illusions provide a powerful method to study the mechanisms that determine how visual input is integrated over space and time. Binocular rivalry occurs when subjects view different images in each eye, and a similar experience called stimulus rivalry occurs even when the left and right images are exchanged at a fast rate. Read More

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Neural Mechanisms Underlying Human Auditory Evoked Responses Revealed By Human Neocortical Neurosolver.

Brain Topogr 2021 Apr 19. Epub 2021 Apr 19.

Department of Neuroscience, Carney Institute for Brain Sciences, Brown University, Providence, USA.

Auditory evoked fields (AEFs) are commonly studied, yet their underlying neural mechanisms remain poorly understood. Here, we used the biophysical modelling software Human Neocortical Neurosolver (HNN) whose foundation is a canonical neocortical circuit model to interpret the cell and network mechanisms contributing to macroscale AEFs elicited by a simple tone, measured with magnetoencephalography. We found that AEFs can be reproduced by activating the neocortical circuit through a layer specific sequence of feedforward and feedback excitatory synaptic drives, similar to prior simulation of somatosensory evoked responses, supporting the notion that basic structures and activation patterns are preserved across sensory regions. Read More

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The location of sucrose synthase in root nodules of white clover.

New Phytol 1995 Aug;130(4):523-530

Cell Biology Department, Institute of Grassland & Environmental Research, Plas Gogerddan, Aberystwyth, Dyfed SY23 3EB, UK.

Immunogold labelling was used to identify the location of the sucrose hydrolytic enzyme sucrose synthase in the N -fixing root nodules of white clover. This is the major enzyme of sucrose cleavage in clover nodules and might be involved in the modulation of N fixation by controlling the rate of utilization of photosynthetic products. Knowledge of the precise cellular location of this enzyme in relation to the point of delivery (the vascular bundles) and the site of utilization of the catabolic product (malate in the bacteroids) might aid our understanding of the metabolic communication between different cell types of the nodule. Read More

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An unusual infection mechanism and nodule morphogenesis in white lupin (Lupinus albus).

New Phytol 2004 Aug;163(2):371-380

Department of Plant Physiology and Biochemistry, Centro de Ciencias Medioambientales, CSIC, Serrano 115-bis, E-28006 Madrid, Spain.

•  The infection of white lupin (Lupinus albus) roots and the early stages in organogenesis of the lupinoid nodule are characterized in detail in this work. •  Immunolabelling of Bradyrhizobium sp. (Lupinus) ISLU16 and green fluorescent protein labelling of Mesorhizobium loti NZP2037, two strains that induce nodulation in L. Read More

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Targeted inoculation of Medicago truncatula in vitro root cultures reveals MtENOD11 expression during early stages of infection by arbuscular mycorrhizal fungi.

New Phytol 2002 Nov;156(2):265-273

Laboratoire de Biologie Moléculaire des Relations Plantes-Microorganismes, UMR215 INRA-CNRS, BP 27, 31326 Castanet Tolosan Cedex, France.

•  An in vitro targeted inoculation technique has been developed for studying the earliest stages of arbuscular endomycorrhizal (AM) infection of Medicago truncatula roots, and in particular the spatio-temporal expression of the early nodulin gene MtENOD11. •  Agrobacterium rhizogenes transformed root explants were derived either from Myc M. truncatula or from the infection-defective Myc mutant TR26 ( dmi2-2 ), both expressing the pMtENOD11-gusA fusion. Read More

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November 2002

Awake epilepsy surgery in patients with focal cortical dysplasia.

World Neurosurg 2021 Apr 16. Epub 2021 Apr 16.

Department of Neurosurgery, University Hospital "St. Ivan Rilski", Sofia, Bulgaria.

Background: Awake craniotomy (AC) and direct electrical stimulation (DES) emerged together with epilepsy surgery more than 80 years ago. The goal of our study was to evaluate the benefits of awake surgery in patients with drug-resistant epilepsy due to focal cortical dysplasia (FCD) affecting eloquent areas.

Methods: Our material included 95 patients with drug-resistant epilepsy and FCD, who were operated on between January 2009 and December 2018. Read More

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Intraoperative mapping of pre-central motor cortex and subcortex: a proposal for supplemental cortical and novel subcortical maps to Penfield's motor homunculus.

Brain Struct Funct 2021 Apr 19. Epub 2021 Apr 19.

Department of Neurosurgery, King's College Hospital NHS Foundation Trust, London, UK.

Penfield's motor homunculus describes a caricaturised yet useful representation of the map of various body parts on the pre-central cortex. We propose a supplemental map of the clinically represented areas of human body in pre-central cortex and a novel subcortical corticospinal tract map. We believe this knowledge is essential for safe surgery in patients with eloquent brain lesions. Read More

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miR-7b-3p Exerts a Dual Role After Spinal Cord Injury, by Supporting Plasticity and Neuroprotection at Cortical Level.

Front Mol Biosci 2021 31;8:618869. Epub 2021 Mar 31.

Department of Neuroscience "Rita Levi Montalcini," Neuroscience Institute Cavalieri Ottolenghi, University of Turin, Orbassano, Italy.

Spinal cord injury (SCI) affects 6 million people worldwide with no available treatment. Despite research advances, the inherent poor regeneration potential of the central nervous system remains a major hurdle. Small RNAs (sRNAs) 19-33 nucleotides in length are a set of non-coding RNA molecules that regulate gene expression and have emerged as key players in regulating cellular events occurring after SCI. Read More

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Specific contribution of neurons from the Dbx1 lineage to the piriform cortex.

Sci Rep 2021 Apr 16;11(1):8349. Epub 2021 Apr 16.

Molecular Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan.

The piriform cortex (PC) is a major cortical processing center for the sense of smell that receives direct inputs from the olfactory bulb. In mice, the PC consists of three neuronal layers, which are populated by cells with distinct developmental origins. One origin of PC neurons is the pool of Dbx1-expressing neural progenitors located in the ventral pallium at the pallial-subpallial boundary. Read More

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Bifurcation analyses and potential landscapes of a cortex-basal ganglia-thalamus model.

IET Syst Biol 2021 May 16;15(3):101-109. Epub 2021 Apr 16.

School of Statistics and Mathematics, Inner Mongolia University of Finance and Economics, Hohhot, China.

The dynamics of cortical neuronal activity plays important roles in controlling body movement and is regulated by connection weights between neurons in a cortex-basal ganglia-thalamus (BGCT) loop. Beta-band oscillation of cortical activity is closely associated with the movement disorder of Parkinson's disease, which is caused by an imbalance in the connection weights of direct and indirect pathways in the BGCT loop. In this study, the authors investigate how the dynamics of cortical activity are modulated by connection weights of direct and indirect pathways in the BGCT loop under low dopamine levels through bifurcation analyses and potential landscapes. Read More

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Learned Overweight Internal Model Can Be Activated to Maintain Equilibrium When Tactile Cues Are Uncertain: Evidence From Cortical and Behavioral Approaches.

Front Hum Neurosci 2021 30;15:635611. Epub 2021 Mar 30.

Aix-Marseille Université, CNRS, Laboratoire de Neurosciences Cognitives, FR 3C, Marseille, France.

Human adaptive behavior in sensorimotor control is aimed to increase the confidence in feedforward mechanisms when sensory afferents are uncertain. It is thought that these feedforward mechanisms rely on predictions from internal models. We investigate whether the brain uses an internal model of physical laws (gravitational and inertial forces) to help estimate body equilibrium when tactile inputs from the foot sole are depressed by carrying extra weight. Read More

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Deciphering Myostatin's Regulatory, Metabolic, and Developmental Influence in Skeletal Diseases.

Front Genet 2021 29;12:662908. Epub 2021 Mar 29.

Department of Biochemistry, University of Missouri, Columbia, MO, United States.

Current research findings in humans and other mammalian and non-mammalian species support the potent regulatory role of myostatin in the morphology and function of muscle as well as cellular differentiation and metabolism, with real-life implications in agricultural meat production and human disease. Myostatin null mice ( ) exhibit skeletal muscle fiber hyperplasia and hypertrophy whereas myostatin deficiency in larger mammals like sheep and pigs engender muscle fiber hyperplasia. Myostatin's impact extends beyond muscles, with alterations in myostatin present in the pathophysiology of myocardial infarctions, inflammation, insulin resistance, diabetes, aging, cancer cachexia, and musculoskeletal disease. Read More

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Perinatal Fentanyl Exposure Leads to Long-Lasting Impairments in Somatosensory Circuit Function and Behavior.

J Neurosci 2021 Apr;41(15):3400-3417

Department of Anatomy and Neurobiology, Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201

One consequence of the opioid epidemic are lasting neurodevelopmental sequelae afflicting adolescents exposed to opioids in the womb. A translationally relevant and developmentally accurate preclinical model is needed to understand the behavioral, circuit, network, and molecular abnormalities resulting from this exposure. By employing a novel preclinical model of perinatal fentanyl exposure, our data reveal that fentanyl has several dose-dependent, developmental consequences to somatosensory function and behavior. Read More

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New-onset lesions on MRI-DWI and cerebral blood flow changes on 3D-pCASL after carotid artery stenting.

Sci Rep 2021 Apr 13;11(1):8005. Epub 2021 Apr 13.

Department of Radiology, Chinese PLA General Hospital, Haidian District, Beijing, China.

This study aimed to investigate the relationship between the new-onset hyperintense lesions on diffusion-weighted images (DWI) and the changes of cerebral blood flow (CBF) before and after carotid artery stenting (CAS) in patients with symptomatic unilateral carotid artery stenosis. Twenty-four patients with symptomatic unilateral carotid stenosis (50-99%) were enrolled. Routine head magnetic resonance imaging and three-dimensional pseudo-continuous arterial spin labeling were taken 7 days before the surgery and for four consecutive days post CAS. Read More

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Modular network between postrhinal visual cortex, amygdala and entorhinal cortex.

J Neurosci 2021 Apr 13. Epub 2021 Apr 13.

Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA

The postrhinal area, POR, is a known center for integrating spatial with non-spatial visual information and a possible hub for influencing landmark navigation by affective input from the amygdala. This may involve specific circuits within muscarinic acetylcholine receptor 2 (M2)-positive or M2-negative modules of POR which associate inputs from the thalamus, cortex, and amygdala and send outputs to the entorhinal cortex. Using anterograde and retrograde labeling with conventional and viral tracers in male and female mice we found that all higher visual areas of the ventral cortical stream project to the amygdala, while such inputs are absent from primary visual cortex (V1) and dorsal stream areas. Read More

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Dissociating perceptual awareness and postperceptual processing: The P300 is not a reliable marker of somatosensory target detection.

J Neurosci 2021 Apr 13. Epub 2021 Apr 13.

Neurocomputation and Neuroimaging Unit, Freie Universität Berlin, 14195 Berlin, Germany.

A central challenge in the study of conscious perception lies in dissociating the neural correlates of perceptual awareness from those reflecting its precursors and consequences. No-report paradigms have been instrumental in this endeavour, demonstrating that the event-related potential P300, recorded from the human scalp, reflects reports rather than awareness. However, these paradigms cannot probe the degree to which stimuli are consciously processed from trial to trial and thus, leave open the possibility that the P300 is a genuine correlate of conscious access enabling reports. Read More

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Elucidating the complementarity of resting-state networks derived from dynamic [F]FDG and hemodynamic fluctuations using simultaneous small-animal PET/MRI.

Neuroimage 2021 Apr 10:118045. Epub 2021 Apr 10.

Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Germany. Electronic address:

Functional connectivity (FC) and resting-state network (RSN) analyses using functional magnetic resonance imaging (fMRI) have evolved into a growing field of research and have provided useful biomarkers for the assessment of brain function in neurological disorders. However, the underlying mechanisms of the blood oxygen level-dependent (BOLD) signal are not fully resolved due to its inherent complexity. In contrast, [F]fluorodeoxyglucose positron emission tomography ([F]FDG-PET) has been shown to provide a more direct measure of local synaptic activity and may have additional value for the readout and interpretation of brain connectivity. Read More

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Serial intravital imaging captures dynamic and functional endothelial remodeling with single-cell resolution.

JCI Insight 2021 Apr 13. Epub 2021 Apr 13.

Department of Physiology and Neuroscience, University of Southern California, Los Angeles, United States of America.

Endothelial cells are important in the maintenance of healthy blood vessels and in the development of vascular diseases. However, the origin and dynamics of endothelial precursors and remodeling at the single-cell level have been difficult to study in vivo due to technical limitations. We aimed to develop a direct visual approach to track the fate and function of single endothelial cells over several days-weeks in the same vascular bed in vivo using multiphoton microscopy (MPM) of transgenic Cdh5-Confetti mice and the kidney glomerulus as a model. Read More

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Defective Reelin/Dab1 signaling pathways associated with disturbed hippocampus development of homozygous yotari mice.

Mol Cell Neurosci 2021 Apr 9;112:103614. Epub 2021 Apr 9.

Department of Immunology and Medicine, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae-ku, Kawasaki 216-8511, Japan. Electronic address:

Homozygous Dab1 yotari mutant mice, Dab1 (yot/yot) mice, have an autosomal recessive mutation of Dab1 and show reeler-like phenotype including histological abnormality of the cerebellum, hippocampus, and cerebral cortex. We here show abnormal hippocampal development of yot/yot mice where granule cells and pyramidal cells fail to form orderly rows but are dispersed diffusely in vague multiplicative layers. Possibly due to the positioning failure of granule cells and pyramidal cells and insufficient synaptogenesis, axons of the granule cells did not extend purposefully to connect with neighboring regions in yot/yot mice. Read More

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Repetitive Transcranial Magnetic Stimulation as a Therapeutic and Probe in Schizophrenia: Examining the Role of Neuroimaging and Future Directions.

Neurotherapeutics 2021 Apr 12. Epub 2021 Apr 12.

Indiana University School of Medicine, Department of Psychiatry, 355W 16 St., Indianapolis, IN, USA.

Schizophrenia is a complex condition associated with perceptual disturbances, decreased motivation and affect, and disrupted cognition. Individuals living with schizophrenia may experience myriad poor outcomes, including impairment in independent living and function as well as decreased life expectancy. Though existing treatments may offer benefit, many individuals still experience treatment resistant and disabling symptoms. Read More

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Conversion of Reactive Astrocytes to Induced Neurons Enhances Neuronal Repair and Functional Recovery After Ischemic Stroke.

Front Aging Neurosci 2021 26;13:612856. Epub 2021 Mar 26.

Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, United States.

The master neuronal transcription factor NeuroD1 can directly reprogram astrocytes into induced neurons (iNeurons) after stroke. Using viral vectors to drive ectopic ND1 expression in gliotic astrocytes after brain injury presents an autologous form of cell therapy for neurodegenerative disease. Cultured astrocytes transfected with ND1 exhibited reduced proliferation and adopted neuronal morphology within 2-3 weeks later, expressed neuronal/synaptic markers, and extended processes. Read More

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Parafascicular Thalamic and Orbitofrontal Cortical Inputs to Striatum Represent States for Goal-Directed Action Selection.

Front Behav Neurosci 2021 19;15:655029. Epub 2021 Mar 19.

Centre for Neuroscience and Regenerative Medicine, University of Technology Sydney, Sydney, NSW, Australia.

Several lines of evidence accrued over the last 5-10 years have converged to suggest that the parafascicular nucleus of the thalamus and the lateral orbitofrontal cortex each represent or contribute to internal state/context representations that guide action selection in partially observable task situations. In rodents, inactivations of each structure have been found to selectively impair performance in paradigms testing goal-directed action selection, but only when that action selection relies on state representations. Electrophysiological evidence has suggested that each structure achieves this function inputs onto cholinergic interneurons (CINs) in the dorsomedial striatum. Read More

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Systemic Review on Transcranial Electrical Stimulation Parameters and EEG/fNIRS Features for Brain Diseases.

Front Neurosci 2021 26;15:629323. Epub 2021 Mar 26.

Department of Rehabilitation Medicine, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan-si, South Korea.

Background: Brain disorders are gradually becoming the leading cause of death worldwide. However, the lack of knowledge of brain disease's underlying mechanisms and ineffective neuropharmacological therapy have led to further exploration of optimal treatments and brain monitoring techniques.

Objective: This study aims to review the current state of brain disorders, which utilize transcranial electrical stimulation (tES) and daily usable noninvasive neuroimaging techniques. Read More

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A Multilevel Examination of Lifetime Aggression: Integrating Cortical Thickness, Personality Pathology, and Trauma Exposure.

Soc Cogn Affect Neurosci 2021 Apr 10. Epub 2021 Apr 10.

University of Delaware, Department of Psychological and Brain Sciences, 108 Wolf Hall, Newark, DE 19176, USA.

Aggression represents a significant public health concern, causing serious physical and psychological harm. Although many studies have sought to characterize the etiology of aggression, research on the contributions of risk factors that span multiple levels of analysis for explaining aggressive behavior is lacking. To address this gap, we investigated the direct and unique contributions of cortical thickness (level 1), pathological personality traits (level 2), and trauma exposure (level 3) for explaining lifetime physical aggression in a high-risk sample of community adults (N = 129, 47. Read More

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Upregulation of miR-499a-5p Decreases Cerebral Ischemia/Reperfusion Injury by Targeting PDCD4.

Cell Mol Neurobiol 2021 Apr 9. Epub 2021 Apr 9.

Department of Anesthesiology, The 1st Affiliated Hospital, School of Medicine, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China.

MiR-499a-5p was significantly downregulated in degenerative tissues and correlated with apoptosis. Nonetheless, the biological function of miR-499a-5p in acute ischemic stroke has been still unclear. In this study, we found that the plasma levels of miR-499a-5p were significantly downregulated in 64 ischemic stroke patients and negatively correlated with the National Institutes of Health Stroke Scale score. Read More

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5-HT receptor- and M muscarinic acetylcholine receptor-mediated activation of Gα in postmortem dorsolateral prefrontal cortex of opiate addicts.

Pharmacol Rep 2021 Apr 9. Epub 2021 Apr 9.

Laboratory of Neuropharmacology, IUNICS/IdISPa, University of the Balearic Islands (UIB), Palma de Mallorca, Spain.

Background: Chronic exposure to opiates causes the development of tolerance and physical dependence as well as persistent brain neuroplasticity. Despite a wealth of postmortem human studies for opiate addicts, little direct information regarding the functional status of serotonergic and cholinergic receptor-mediated signaling pathways in the human brain of opiate addicts is yet available.

Methods: Functional activation of Gα proteins coupled to 5-HT and M type muscarinic acetylcholine receptor (mAChR) was assessed by using the method named [S]GTPγS binding/immunoprecipitation in frontal cortical membrane preparations from postmortem human brains obtained from opiate addicts and matched controls. Read More

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Morphological Changes in Cortical and Subcortical Structures in Multiple System Atrophy Patients With Mild Cognitive Impairment.

Front Hum Neurosci 2021 23;15:649051. Epub 2021 Mar 23.

Department of Radiology, The First Hospital, China Medical University, Shenyang, China.

Objective: This study aimed to investigate the morphometric alterations in the cortical and subcortical structures in multiple system atrophy (MSA) patients with mild cognitive impairment (MCI), and to explore the association with cognitive deficits.

Methods: A total of 45 MSA patients (25 MSA-only, 20 MSA-MCI) and 29 healthy controls were recruited. FreeSurfer software was used to analyze cortical thickness, and voxel-based morphometry was used to analyze the gray matter volumes. Read More

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Effects of transcranial direct current stimulation on balance after ischemic stroke (SANDE trial): Study protocol for a multicentric randomized controlled trial.

Contemp Clin Trials 2021 Apr 5;105:106396. Epub 2021 Apr 5.

Physical Therapy Department, Federal University of Triângulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil. Electronic address:

Background: Among the tools used for motor rehabilitation after stroke, transcranial direct current electrical stimulation (tDCS) aims to modify cortical excitability and improve motor function. Despite promising results, the effects of tDCS on balance after stroke have not yet been assessed using specific protocols. Therefore, this study will aim to evaluate the effects of tDCS and rehabilitation on balance after stroke. Read More

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