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1.
Cereb Cortex ; 34(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39066504

RESUMO

The cerebral cortex has long been thought to be involved in the pathophysiology of motor symptoms of Parkinson's disease. The impaired cortical function is believed to be a direct and immediate effect of pathologically patterned basal ganglia output, mediated to the cerebral cortex by way of the ventral motor thalamus. However, recent studies in humans with Parkinson's disease and in animal models of the disease have provided strong evidence suggesting that the involvement of the cerebral cortex is much broader than merely serving as a passive conduit for subcortical disturbances. In the present review, we discuss Parkinson's disease-related changes in frontal cortical motor regions, focusing on neuropathology, plasticity, changes in neurotransmission, and altered network interactions. We will also examine recent studies exploring the cortical circuits as potential targets for neuromodulation to treat Parkinson's disease.


Assuntos
Córtex Motor , Doença de Parkinson , Doença de Parkinson/fisiopatologia , Doença de Parkinson/patologia , Humanos , Córtex Motor/fisiopatologia , Animais , Plasticidade Neuronal/fisiologia , Vias Neurais/fisiopatologia
2.
J Integr Neurosci ; 23(7): 132, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39082301

RESUMO

BACKGROUND: Non-invasive brain mapping using navigated transcranial magnetic stimulation (nTMS) is a valuable tool prior to resection of malignant brain tumors. With nTMS motor mapping, it is additionally possible to analyze the function of the motor system and to evaluate tumor-induced neuroplasticity. Distinct changes in motor cortex excitability induced by certain malignant brain tumors are a focal point of research. METHODS: A retrospective single-center study was conducted involving patients with malignant brain tumors. Clinical data, resting motor threshold (rMT), and nTMS-based tractography were evaluated. The interhemispheric rMT-ratio (rMTTumor/rMTControl) was calculated for each extremity and considered pathological if it was >110% or <90%. Distances between the corticospinal tract and the tumor (lesion-to-tract-distance - LTD) were measured. RESULTS: 49 patients were evaluated. 16 patients (32.7%) had a preoperative motor deficit. The cohort comprised 22 glioblastomas (44.9%), 5 gliomas of Classification of Tumors of the Central Nervous System (CNS WHO) grade 3 (10.2%), 6 gliomas of CNS WHO grade 2 (12.2%) and 16 cerebral metastases (32.7%). 26 (53.1%) had a pathological rMT-ratio for the upper extremity and 35 (71.4%) for the lower extremity. All patients with tumor-induced motor deficits had pathological interhemispheric rMT-ratios, and presence of tumor-induced motor deficits was associated with infiltration of the tumor to the nTMS-positive cortex (p = 0.04) and shorter LTDs (all p < 0.021). Pathological interhemispheric rMT-ratio for the upper extremity was associated with cerebral metastases, but not with gliomas (p = 0.002). CONCLUSIONS: Our study underlines the diagnostic potential of nTMS motor mapping to go beyond surgical risk stratification. Pathological alterations in motor cortex excitability can be measured with nTMS mapping. Pathological cortical excitability was more frequent in cerebral metastases than in gliomas.


Assuntos
Neoplasias Encefálicas , Imagem de Tensor de Difusão , Córtex Motor , Tratos Piramidais , Estimulação Magnética Transcraniana , Humanos , Tratos Piramidais/fisiopatologia , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/patologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Idoso , Glioma/fisiopatologia , Glioma/patologia , Glioma/diagnóstico por imagem , Mapeamento Encefálico , Potencial Evocado Motor/fisiologia
3.
CNS Neurosci Ther ; 30(7): e14889, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39073240

RESUMO

BACKGROUND: Upper limb motor impairment commonly occurs after stroke, impairing quality of life. Brain network reorganization likely differs between subgroups with differing impairment severity. This study explored differences in functional connectivity (FC) and corticospinal tract (CST) integrity between patients with mild/moderate versus severe hemiplegia poststroke to clarify the neural correlates underlying motor deficits. METHOD: Sixty chronic stroke patients with upper limb motor impairment were categorized into mild/moderate and severe groups based on Fugl-Meyer scores. Resting-state FC was assessed using functional near-infrared spectroscopy (fNIRS) to compare connectivity patterns between groups across motor regions. CST integrity was evaluated by inducing motor evoked potentials (MEP) via transcranial magnetic stimulation. RESULTS: Compared to the mild/moderate group, the severe group exhibited heightened premotor cortex-primary motor cortex (PMC-M1) connectivity (t = 4.56, p < 0.01). Absence of MEP was also more frequent in the severe group (χ2 = 12.31, p = 0.01). Bayesian models effectively distinguished subgroups and identified the PMC-M1 connection as highly contributory (accuracy = 91.30%, area under the receiver operating characteristic curve [AUC] = 0.86). CONCLUSION: Distinct patterns of connectivity and corticospinal integrity exist between stroke subgroups with differing impairments. Strengthened connectivity potentially indicates recruitment of additional motor resources to compensate for damage. These findings elucidate the neural correlates underlying motor deficits poststroke and could guide personalized, network-based therapies targeting predictive biomarkers to improve rehabilitation outcomes.


Assuntos
Potencial Evocado Motor , Tratos Piramidais , Espectroscopia de Luz Próxima ao Infravermelho , Acidente Vascular Cerebral , Estimulação Magnética Transcraniana , Humanos , Masculino , Feminino , Estimulação Magnética Transcraniana/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Pessoa de Meia-Idade , Idoso , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Potencial Evocado Motor/fisiologia , Tratos Piramidais/fisiopatologia , Tratos Piramidais/diagnóstico por imagem , Doença Crônica , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem , Biomarcadores , Adulto
4.
Physiother Res Int ; 29(3): e2111, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39014876

RESUMO

BACKGROUND: Aberrant movement in chronic low back pain (CLBP) is associated with a deficit in the lumbar multifidus (LM) and changes in cortical topography. Anodal transcranial direct current stimulation (a-tDCS) can be used to enhance cortical excitability by priming the neuromuscular system for motor control exercise (MCE), thereby enhancing LM activation and movement control. This study aimed to determine the effects of a 6-week MCE program combined with a-tDCS on cortical topography, LM activation, movement patterns, and clinical outcomes in individuals with CLBP. METHODS: Twenty-two individuals with CLBP were randomly allocated to the a-tDCS group (a-tDCS; n = 12) or sham-tDCS group (s-tDCS; n = 10). Both groups received 20 min of tDCS followed by 30 min of MCE. The LM and erector spinae (ES) cortical topography, LM activation, movement control battery tests, and clinical outcomes (disability and quality of life) were measured pre- and post-intervention. RESULTS: Significant interaction (group × time; p < 0.01) was found in the distance between LM and ES cortical locations. The a-tDCS group demonstrated significantly fewer discrete peaks (p < 0.05) in both ES and LM and significant improvements (p < 0.05) in clinical outcomes post-intervention. The s-tDCS group demonstrated a significant increase (p < 0.05) in the number of discrete peaks in the LM cortical topography. No significant changes (p > 0.05) in LM activation were observed in either group; however, both groups demonstrated improved movement patterns. DISCUSSION: Our findings suggest that combined a-tDCS with MCE can separate LM and ES locations over time while s-tDCS (MCE alone) reduces the distance. Our study did not find superior benefits of adding a-tDCS before MCE for LM activation, movement patterns, or clinical outcomes.


Assuntos
Terapia por Exercício , Dor Lombar , Estimulação Transcraniana por Corrente Contínua , Humanos , Dor Lombar/terapia , Dor Lombar/reabilitação , Feminino , Masculino , Adulto , Terapia por Exercício/métodos , Pessoa de Meia-Idade , Córtex Motor/fisiologia , Córtex Motor/fisiopatologia , Resultado do Tratamento , Músculos Paraespinais/fisiologia , Qualidade de Vida , Dor Crônica/terapia , Dor Crônica/reabilitação
5.
Sci Rep ; 14(1): 16527, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020053

RESUMO

Central post-stroke pain (CPSP) is a chronic pain resulting from a lesion in somatosensory pathways. Neuromodulation techniques, such as repetitive transcranial magnetic stimulation (rTMS) that target the primary motor cortex (M1), have shown promise for the treatment of CPSP. High-frequency (Hf) rTMS exhibits analgesic effects compared to low-frequency (Lf) rTMS; however, its analgesic mechanism is unknown. We aimed to elucidate the mechanism of rTMS-induced analgesia by evaluating alterations of tactile functional magnetic resonance imaging (fMRI) due to Hf- and Lf-rTMS in a CPSP monkey model. Consistent with the patient findings, the monkeys showed an increase in pain threshold after Hf-rTMS, which indicated an analgesic effect. However, no change after Lf-rTMS was observed. Compared to Lf-rTMS, Hf-rTMS produced enhanced tactile-evoked fMRI signals not only in M1 but also in somatosensory processing regions, such as the primary somatosensory and midcingulate cortices. However, the secondary somatosensory cortex (S2) was less active after Hf-rTMS than after Lf-rTMS, suggesting that activation of this region was involved in CPSP. Previous studies showed pharmacological inhibition of S2 reduces CPSP-related behaviors, and the present results emphasize the involvement of an S2 inhibitory system in rTMS-induced analgesia. Verification using the monkey model is important to elucidate the inhibition system.


Assuntos
Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral , Estimulação Magnética Transcraniana , Animais , Estimulação Magnética Transcraniana/métodos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem , Córtex Somatossensorial/fisiopatologia , Córtex Somatossensorial/diagnóstico por imagem , Masculino , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Limiar da Dor , Manejo da Dor/métodos , Dor Crônica/terapia , Dor Crônica/fisiopatologia , Dor Crônica/etiologia
6.
Brain Behav ; 14(7): e3605, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38956819

RESUMO

BACKGROUND: High-frequency repeated transcranial magnetic stimulation (rTMS) stimulating the primary motor cortex (M1) is an alternative, adjunctive therapy for improving the motor symptoms of Parkinson's disease (PD). However, whether the high frequency of rTMS positively correlates to the improvement of motor symptoms of PD is still undecided. By controlling for other parameters, a disease animal model may be useful to compare the neuroprotective effects of different high frequencies of rTMS. OBJECTIVE: The current exploratory study was designed to compare the protective effects of four common high frequencies of rTMS (5, 10, 15, and 20 Hz) and iTBS (a special form of high-frequency rTMS) and explore the optimal high-frequency rTMS on an animal PD model. METHODS: Following high frequencies of rTMS application (twice a week for 5 weeks) in a MPTP/probenecid-induced chronic PD model, the effects of the five protocols on motor behavior as well as dopaminergic neuron degeneration levels were identified. The underlying molecular mechanisms were further explored. RESULTS: We found that all the high frequencies of rTMS had protective effects on the motor functions of PD models to varying degrees. Among them, the 10, 15, and 20 Hz rTMS interventions induced comparable preservation of motor function through the protection of nigrostriatal dopamine neurons. The enhancement of brain-derived neurotrophic factor (BDNF), dopamine transporter (DAT), and vesicular monoamine transporter 2 (VMAT-2) and the suppression of TNF-α and IL-1ß in the nigrostriatum were involved in the process. The efficacy of iTBS was inferior to that of the above three protocols. The effect of 5 Hz rTMS protocol was weakest. CONCLUSIONS: Combined with the results of the present study and the possible side effects induced by rTMS, we concluded that 10 Hz might be the optimal stimulation frequency for preserving the motor functions of PD models using rTMS treatment.


Assuntos
Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Transtornos Parkinsonianos , Probenecid , Estimulação Magnética Transcraniana , Animais , Estimulação Magnética Transcraniana/métodos , Camundongos , Masculino , Probenecid/farmacologia , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/terapia , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Córtex Motor/metabolismo , Córtex Motor/fisiopatologia , Neurônios Dopaminérgicos/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Interleucina-1beta/metabolismo , Substância Negra/metabolismo , Corpo Estriado/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Intoxicação por MPTP/terapia , Intoxicação por MPTP/prevenção & controle , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/fisiopatologia , Atividade Motora/fisiologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia
7.
PLoS Comput Biol ; 20(7): e1012259, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38968294

RESUMO

Cognitive disorders, including Down syndrome (DS), present significant morphological alterations in neuron architectural complexity. However, the relationship between neuromorphological alterations and impaired brain function is not fully understood. To address this gap, we propose a novel computational model that accounts for the observed cell deformations in DS. The model consists of a cross-sectional layer of the mouse motor cortex, composed of 3000 neurons. The network connectivity is obtained by accounting explicitly for two single-neuron morphological parameters: the mean dendritic tree radius and the spine density in excitatory pyramidal cells. We obtained these values by fitting reconstructed neuron data corresponding to three mouse models: wild-type (WT), transgenic (TgDyrk1A), and trisomic (Ts65Dn). Our findings reveal a dynamic interplay between pyramidal and fast-spiking interneurons leading to the emergence of gamma activity (∼40 Hz). In the DS models this gamma activity is diminished, corroborating experimental observations and validating our computational methodology. We further explore the impact of disrupted excitation-inhibition balance by mimicking the reduction recurrent inhibition present in DS. In this case, gamma power exhibits variable responses as a function of the external input to the network. Finally, we perform a numerical exploration of the morphological parameter space, unveiling the direct influence of each structural parameter on gamma frequency and power. Our research demonstrates a clear link between changes in morphology and the disruption of gamma oscillations in DS. This work underscores the potential of computational modeling to elucidate the relationship between neuron architecture and brain function, and ultimately improve our understanding of cognitive disorders.


Assuntos
Biologia Computacional , Síndrome de Down , Modelos Neurológicos , Síndrome de Down/fisiopatologia , Síndrome de Down/patologia , Animais , Camundongos , Células Piramidais/patologia , Células Piramidais/fisiologia , Neurônios/fisiologia , Neurônios/patologia , Interneurônios/fisiologia , Interneurônios/patologia , Simulação por Computador , Córtex Motor/fisiopatologia , Córtex Motor/patologia , Modelos Animais de Doenças , Humanos , Camundongos Transgênicos , Rede Nervosa/fisiopatologia , Rede Nervosa/patologia
8.
Parkinsonism Relat Disord ; 125: 107049, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955097

RESUMO

INTRODUCTION: Parkinson's disease (PD) presents with a progressive decline in manual dexterity, attributed to dysfunction in the basal ganglia-thalamus-cortex loop, influenced by dopaminergic deficits in the striatum. Recent research suggests that the motor cortex may play a pivotal role in mediating the relationship between striatal dopamine depletion and motor function in PD. Understanding this connection is crucial for comprehending the origins of manual dexterity impairments in PD. Therefore, our study aimed to explore how motor cortex activation mediates the association between striatal dopamine depletion and manual dexterity in PD. MATERIALS AND METHODS: We enrolled 26 mildly affected PD patients in their off-medication phase to undergo [18F]FDOPA PET/CT scans for evaluating striatal dopaminergic function. EEG recordings were conducted during bimanual anti-phase finger tapping tasks to evaluate motor cortex activity, specifically focusing on Event-Related Desynchronization in the beta band. Manual dexterity was assessed using the Purdue Pegboard Test. Regression-based mediation analysis was conducted to examine whether motor cortex activation mediates the association between striatal dopamine depletion and manual dexterity in PD. RESULTS: Mediation analysis revealed a significant direct effect of putamen dopamine depletion on manual dexterity for the affected hand and assembly tasks (performed with two hands), with motor cortex activity mediating this association. In contrast, while caudate nucleus dopamine depletion showed a significant direct effect on manual dexterity, motor cortex mediation on this association was not observed. CONCLUSION: Our study confirms the association between striatum dopamine depletion and impaired manual dexterity in PD, with motor cortex activity mediating this relationship.


Assuntos
Dopamina , Córtex Motor , Doença de Parkinson , Humanos , Doença de Parkinson/fisiopatologia , Doença de Parkinson/metabolismo , Doença de Parkinson/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/metabolismo , Dopamina/metabolismo , Destreza Motora/fisiologia , Corpo Estriado/metabolismo , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/fisiopatologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Eletroencefalografia , Di-Hidroxifenilalanina/análogos & derivados
9.
Sci Rep ; 14(1): 15645, 2024 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977806

RESUMO

Understanding the response of the injured brain to different transcranial direct current stimulation (tDCS) montages may help explain the variable tDCS treatment results on poststroke motor gains. Cortical connectivity has been found to reflect poststroke motor gains and cortical plasticity, but the changes in connectivity following tDCS remain unknown. We aimed to investigate the relationship between tDCS-induced changes in cortical connectivity and poststroke motor gains. In this study, participants were assigned to receive four tDCS montages (anodal, cathodal, bilateral, and sham) over the primary motor cortex (M1) according to a single-blind, randomized, crossover design. Electroencephalography (EEG) and Jebsen-Taylor hand function test (JTT) were performed before and after the intervention. Motor cortical connectivity was measured using beta-band coherence with the ipsilesional and contralesional M1 as seed regions. Motor gain was evaluated based on the JTT completion time. We examined the relationship between baseline connectivity and clinical characteristics and that between changes in connectivity and motor gains after different tDCS montages. Baseline functional connectivity, motor impairment, and poststroke duration were correlated. High ipsilesional M1-frontal-temporal connectivity was correlated with a good baseline motor status, and increased connectivity was accompanied by good functional improvement following anodal tDCS treatment. Low contralesional M1-frontal-central connectivity was correlated with a good baseline motor status, and decreased connectivity was accompanied by good functional improvement following cathodal tDCS treatment. In conclusion, EEG-based motor cortical connectivity was correlated with stroke characteristics, including motor impairment and poststroke duration, and motor gains induced by anodal and cathodal tDCS.


Assuntos
Estudos Cross-Over , Eletroencefalografia , AVC Isquêmico , Córtex Motor , Estimulação Transcraniana por Corrente Contínua , Humanos , Córtex Motor/fisiopatologia , Estimulação Transcraniana por Corrente Contínua/métodos , Masculino , Feminino , Pessoa de Meia-Idade , AVC Isquêmico/fisiopatologia , AVC Isquêmico/terapia , Método Simples-Cego , Idoso , Reabilitação do Acidente Vascular Cerebral/métodos , Adulto , Plasticidade Neuronal/fisiologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-39018214

RESUMO

Parkinson's disease (PD) is characterized by decreased dopamine in the basal ganglia that causes excessive tonic inhibition of the thalamus. This excessive inhibition seems to explain inhibitory motor symptoms in PD, but the source of tremor remains unclear. This paper investigates how neural inhibition may change the closed-loop characteristics of the human motor control system to determine how this established pathophysiology could produce tremor. The rate-coding model of neural signals suggests increased inhibition decreases signal amplitude, which could create a mismatch between the closed-loop dynamics and the internal models that overcome proprioceptive feedback delays. This paper aims to identify a candidate model structure with decreased-amplitude-induced tremor in PD that also agrees with previously recorded movements of healthy and cerebellar patients. The optimal feedback control theory of human motor control forms the basis of the model. Key additional elements include gating of undesired movements via the basal ganglia-thalamus-motor cortex circuit and the treatment of the efferent copy of the control input as a measurement in the state estimator. Simulations confirm the model's ability to capture tremor in PD and also demonstrate how disease progression could affect tremor and other motor symptoms, providing insight into the existence of tremor and non-tremor phenotypes. Altogether, the physiological underpinnings of the model structure and the agreement of model predictions with clinical observations provides support for the hypothesis that unstable feedback produces parkinsonian tremor. Consequently, these results also support the associated framework for the neuroanatomy of human motor control.


Assuntos
Gânglios da Base , Simulação por Computador , Doença de Parkinson , Tremor , Humanos , Tremor/fisiopatologia , Tremor/etiologia , Gânglios da Base/fisiopatologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/complicações , Modelos Neurológicos , Córtex Motor/fisiopatologia , Tálamo/fisiopatologia , Algoritmos , Retroalimentação Fisiológica , Cerebelo/fisiopatologia , Movimento/fisiologia
12.
Am J Speech Lang Pathol ; 33(4): 2023-2040, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38875479

RESUMO

PURPOSE: Repetitive transcranial magnetic stimulation (rTMS) can enhance aphasia recovery. Most studies have used inhibitory stimulation targeting the right inferior frontal gyrus. However, the motor cortex, observed to contribute to the prediction of aphasia recovery, is involved in word production and could be an appropriate target for rTMS. We aimed to observe behavioral changes in a picture naming task induced by inhibitory rTMS targeting the right motor cortex of the lips in people with poststroke aphasia. METHOD: Using a single-case experimental design, we included three participants with chronic poststroke aphasia who had phonological deficits. Each participant performed a verbal picture naming task 3 times a week for 2, 3, or 4 weeks (pseudorandom across participants) to establish a baseline naming ability for each participant. These were not therapy sessions, and no feedback was provided. Then, each participant received the intervention, inhibitory continuous theta burst stimulation targeting the right motor cortex of the lips, 3 times a week for 2 weeks. Naming testing continued 3 times a week, for these latter 2 weeks. No therapy was performed at any time during the study. RESULTS: Visual analysis of the graphs showed a positive effect of rTMS for P2 and P3 on picture naming accuracy and a tendency toward improvement for P1. Statistical analysis showed an improvement after rTMS for P1 (τ = 0.544, p = .013, SETau = 0.288) and P2 (τ = 0.708, p = .001, SETau = 0.235). For P3, even if the intervention allowed some improvement, this was statistically nonsignificant due to a learning effect during the baseline naming testing, which lasted the longest, 4 weeks. Regarding specific language features, phonological errors significantly decreased in all patients. CONCLUSIONS: The motor cortex of the lips could be an appropriate target for rTMS to improve naming in people with poststroke aphasia suffering from a phonological deficit. This suggests the possibility to individualize the target for rTMS, according to the patient's linguistic impairment.


Assuntos
Lábio , Córtex Motor , Acidente Vascular Cerebral , Estimulação Magnética Transcraniana , Humanos , Córtex Motor/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Masculino , Lábio/inervação , Pessoa de Meia-Idade , Feminino , Idoso , Acidente Vascular Cerebral/complicações , Afasia/etiologia , Afasia/terapia , Resultado do Tratamento , Fonética , Transtornos da Articulação/terapia , Transtornos da Articulação/etiologia , Reabilitação do Acidente Vascular Cerebral/métodos
13.
Sci Rep ; 14(1): 14858, 2024 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937566

RESUMO

Research to improve and expand treatment options for motor impairment after stroke remains an important issue in rehabilitation as the reduced ability to move affected limbs is still a limiting factor in the selection of training content for stroke patients. The combination of action observation and peripheral nerve stimulation is a promising method for inducing increased excitability and plasticity in the primary motor cortex of healthy subjects. In addition, as reported in the literature, the use of action observation and motor imagery in conjunction has an advantage over the use of one or the other alone in terms of the activation of motor-related brain regions. The aim of the pilot study was thus to combine these findings into a multimodal approach and to evaluate the potential impact of the concurrent application of the three methods on dexterity in stroke patients. The paradigm developed accordingly was tested with 10 subacute patients, in whom hand dexterity, thumb-index pinch force and thumb tapping speed were measured for a baseline assessment and directly before and after the single intervention. During the 10-min session, patients were instructed to watch a repetitive thumb-index finger tapping movement displayed on a monitor and to imagine the sensations that would arise from physically performing the same motion. They were also repeatedly electrically stimulated at the wrist on the motorically more affected body side and asked to place their hand behind the monitor for the duration of the session to support integration of the displayed hand into their own body schema. The data provide a first indication of a possible immediate effect of a single application of this procedure on the dexterity in patients after stroke.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Projetos Piloto , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/métodos , Córtex Motor/fisiopatologia , Nervos Periféricos/fisiopatologia , Nervos Periféricos/fisiologia , Imagens, Psicoterapia/métodos , Adulto , Destreza Motora/fisiologia , Estimulação Elétrica/métodos
14.
CNS Neurosci Ther ; 30(6): e14792, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38867393

RESUMO

AIMS: Parkinson's disease (PD) patients experience improvement in motor symptoms after deep brain stimulation (DBS) and before initiating stimulation. This is called the microlesion effect. However, the mechanism remains unclear. The study aims to comprehensively explore the changes in functional connectivity (FC) patterns in movement-related brain regions in PD patients during the microlesion phase through seed-based FC analysis. METHODS: The study collected the resting functional magnetic resonance imaging data of 49 PD patients before and after DBS surgery (off stimulation). The cortical and subcortical areas related to motor function were selected for seed-based FC analysis. Meanwhile, their relationship with the motor scale was investigated. RESULTS: The motor-related brain regions were selected as the seed point, and we observed various FC declines within the motor network brain regions. These declines were primarily in the left middle temporal gyrus, bilateral middle frontal gyrus, right supplementary motor area, left precentral gyrus, left postcentral gyrus, left inferior frontal gyrus, and right superior frontal gyrus after DBS. CONCLUSION: The movement-related network was extensively reorganized during the microlesion period. The study provided new information on enhancing motor function from the network level post-DBS.


Assuntos
Estimulação Encefálica Profunda , Imageamento por Ressonância Magnética , Doença de Parkinson , Humanos , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia
17.
J Neuroeng Rehabil ; 21(1): 101, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872209

RESUMO

BACKGROUND: In post-stroke rehabilitation, functional connectivity (FC), motor-related cortical potential (MRCP), and gait activities are common measures related to recovery outcomes. However, the interrelationship between FC, MRCP, gait activities, and bipedal distinguishability have yet to be investigated. METHODS: Ten participants were equipped with EEG devices and inertial measurement units (IMUs) while performing lower limb motor preparation (MP) and motor execution (ME) tasks. MRCP, FCs, and bipedal distinguishability were extracted from the EEG signals, while the change in knee degree during the ME phase was calculated from the gait data. FCs were analyzed with pairwise Pearson's correlation, and the brain-wide FC was fed into support vector machine (SVM) for bipedal classification. RESULTS: Parietal-frontocentral connectivity (PFCC) dysconnection and MRCP desynchronization were related to the MP and ME phases, respectively. Hemiplegic limb movement exhibited higher PFCC strength than nonhemiplegic limb movement. Bipedal classification had a short-lived peak of 75.1% in the pre-movement phase. These results contribute to a better understanding of the neurophysiological functions during motor tasks, with respect to localized MRCP and nonlocalized FC activities. The difference in PFCCs between both limbs could be a marker to understand the motor function of the brain of post-stroke patients. CONCLUSIONS: In this study, we discovered that PFCCs are temporally dependent on lower limb gait movement and MRCP. The PFCCs are also related to the lower limb motor performance of post-stroke patients. The detection of motor intentions allows the development of bipedal brain-controlled exoskeletons for lower limb active rehabilitation.


Assuntos
Eletroencefalografia , Marcha , Lobo Parietal , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Masculino , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/complicações , Feminino , Pessoa de Meia-Idade , Marcha/fisiologia , Lobo Parietal/fisiopatologia , Lobo Parietal/fisiologia , Potencial Evocado Motor/fisiologia , Lobo Frontal/fisiopatologia , Lobo Frontal/fisiologia , Idoso , Adulto , Córtex Motor/fisiopatologia , Córtex Motor/fisiologia , Máquina de Vetores de Suporte
18.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38879808

RESUMO

Navigated repetitive transmagnetic stimulation is a non-invasive and safe brain activity modulation technique. When combined with the classical rehabilitation process in stroke patients it has the potential to enhance the overall neurologic recovery. We present a case of a peri-operative stroke, treated with ultra-early low frequency navigated repetitive transmagnetic stimulation over the contralesional hemisphere. The patient received low frequency navigated repetitive transmagnetic stimulation within 12 hours of stroke onset for seven consecutive days and a significant improvement in his right sided weakness was noticed and he was discharge with normal power. This was accompanied by an increase in the number of positive responses evoked by navigated repetitive transmagnetic stimulation and a decrease of the resting motor thresholds at a cortical level. Subcortically, a decrease in the radial, axial, and mean diffusivity were recorded in the ipsilateral corticospinal tract and an increase in fractional anisotropy, axial diffusivity, and mean diffusivity was observed in the interhemispheric fibers of the corpus callosum responsible for the interhemispheric connectivity between motor areas. Our case demonstrates clearly that ultra-early low frequency navigated repetitive transmagnetic stimulation applied to the contralateral motor cortex can lead to significant clinical motor improvement in patients with subcortical stroke.


Assuntos
Acidente Vascular Cerebral , Estimulação Magnética Transcraniana , Humanos , Masculino , Estimulação Magnética Transcraniana/métodos , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/cirurgia , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem , Pessoa de Meia-Idade , Idoso , Tratos Piramidais/fisiopatologia , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Potencial Evocado Motor/fisiologia
19.
BMC Neurol ; 24(1): 213, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909175

RESUMO

BACKGROUND: After spinal cord injury (SCI), a large number of survivors suffer from severe motor dysfunction (MD). Although the injury site is in the spinal cord, excitability significantly decreases in the primary motor cortex (M1), especially in the lower extremity (LE) area. Unfortunately, M1 LE area-targeted repetitive transcranial magnetic stimulation (rTMS) has not achieved significant motor improvement in individuals with SCI. A recent study reported that the M1 hand area in individuals with SCl contains a compositional code (the movement-coding component of neural activity) that links matching movements from the upper extremities (UE) and the LE. However, the correlation between bilateral M1 hand area excitability and overall functional recovery is unknown. OBJECTIVE: To clarify the changes in the excitability of the bilateral M1 hand area after SCI and its correlation with motor recovery, we aim to specify the therapeutic parameters of rTMS for SCI motor rehabilitation. METHODS: This study is a 12-month prospective cohort study. The neurophysiological and overall functional status of the participants will be assessed. The primary outcomes included single-pulse and paired-pulse TMS. The second outcome included functional near-infrared spectroscopy (fNIRS) measurements. Overall functional status included total motor score, modified Ashworth scale score, ASIA Impairment Scale grade, spinal cord independence measure and modified Barthel index. The data will be recorded for individuals with SCI at disease durations of 1 month, 2 months, 4 months, 6 months and 12 months. The matched healthy controls will be measured during the same period of time after recruitment. DISCUSSION: The present study is the first to analyze the role of bilateral M1 hand area excitability changes in the evaluation and prediction of overall functional recovery (including motor function and activities of daily living) after SCI, which will further expand the traditional theory of the predominant role of M1, optimize the current rTMS treatment, and explore the brain-computer interface design for individuals with SCI. TRIAL REGISTRATION NUMBER: ChiCTR2300068831.


Assuntos
Mãos , Córtex Motor , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal , Estimulação Magnética Transcraniana , Humanos , Traumatismos da Medula Espinal/reabilitação , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Recuperação de Função Fisiológica/fisiologia , Mãos/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Córtex Motor/fisiopatologia , Estudos Prospectivos , Potencial Evocado Motor/fisiologia , Masculino , Adulto , Feminino , Estudos de Coortes , Pessoa de Meia-Idade , Espectroscopia de Luz Próxima ao Infravermelho/métodos
20.
Hum Brain Mapp ; 45(8): e26723, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38864296

RESUMO

This study aims to investigate the structural reorganization in the sensorimotor area of the brain in patients with gliomas, distinguishing between those with impaired and unimpaired strength. Using voxel-based morphometry (VBM) and region of interest (ROI) analysis, gray matter volumes (GMV) were compared in the contralesional primary motor gyrus, primary sensory gyrus, premotor area, bilateral supplementary motor area, and medial Brodmann area 8 (BA8). The results revealed that in patients with right hemisphere gliomas, the right medial BA8 volume was significantly larger in the impaired group than in the unimpaired group, with both groups exceeding the volume in 16 healthy controls (HCs). In patients with left hemisphere gliomas, the right supplementary motor area (SMA) was more pronounced in the impaired group compared to the unimpaired group, and both groups were greater than HCs. Additionally, the volumes of the right medial BA8 in both the impaired group were greater than HCs. Contralateral expansions in the gray matter of hand- and trunk-related cortices of the premotor area, precentral gyrus, and postcentral gyrus were observed compared to HCs. Furthermore, a negative correlation was found between hand Medical Research Council (MRC) score and volumes of the contralateral SMA and bilateral medial BA8. Notably, our findings reveal consistent results across both analytical approaches in identifying significant structural reorganizations within the sensorimotor cortex. These consistent findings underscore the adaptive neuroplastic responses to glioma presence, highlighting potential areas of interest for further neurosurgical planning and rehabilitation strategies.


Assuntos
Neoplasias Encefálicas , Lateralidade Funcional , Glioma , Imageamento por Ressonância Magnética , Córtex Sensório-Motor , Humanos , Masculino , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/fisiopatologia , Feminino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Adulto , Pessoa de Meia-Idade , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/patologia , Córtex Sensório-Motor/fisiopatologia , Lateralidade Funcional/fisiologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Córtex Motor/fisiopatologia , Mapeamento Encefálico , Adulto Jovem
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