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1.
J Stroke Cerebrovasc Dis ; 30(1): 105447, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33188953

RESUMO

BACKGROUND: Hand motor function is often severely affected in patients with hemorrhagic stroke. The present study aimed to investigate the feasibility of predicting hand function recovery after hypertensive intracerebral hemorrhage using diffusion tensor imaging (DTI). METHODS: A total of 75 patients with hypertensive intracerebral hemorrhage were prospectively included. DTI of the corticospinal tract (CST) connecting the hand knob area of the precentral gyrus and the cerebral peduncle was performed at around 3 weeks after stroke. Integrity of the CST was evaluated as no disruption, partial disruption, and complete disruption. Hand function was compared by the Brunnstrom recovery stage of hand (BRS-H) at post-stroke 3 weeks and 3 months. RESULTS: Degrees of integrity of the corticospinal cord was negatively correlated with the BRS-H at both post-stroke 3 weeks (r = -0.77, p < 0.01) and 3 months (r = -0.75, p < 0.01). Patients with intact CST or completely disrupted CST shown by DTI did not show significant improvement in the BRS-H at post-stroke 3 months. However, those with partially disrupted CST showed significant improvement in the BRS-H at post-stroke 3 months compared to 3 weeks (3.79 ± 1.36 vs 2.53 ± 1.58, p = 0.012). CONCLUSIONS: DTI can be used to visualize the damage to the hand fibers of the CST. Patients with partially disrupted CST may benefit most from rehabilitation therapy for hand function recovery after hypertensive intracerebral hemorrhage.


Assuntos
Imagem de Tensor de Difusão , Mãos/inervação , Atividade Motora , Córtex Motor/diagnóstico por imagem , Tratos Piramidais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , /fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Valor Preditivo dos Testes , Estudos Prospectivos , Tratos Piramidais/fisiopatologia , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral , Fatores de Tempo , Resultado do Tratamento
2.
Sci Rep ; 10(1): 16987, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046800

RESUMO

Age-related hearing loss has been related to a compensatory increase in audio-visual integration and neural reorganization including alterations in functional resting state connectivity. How these two changes are linked in elderly listeners is unclear. The current study explored modulatory effects of hearing thresholds and audio-visual integration on resting state functional connectivity. We analysed a large set of resting state data of 65 elderly participants with a widely varying degree of untreated hearing loss. Audio-visual integration, as gauged with the McGurk effect, increased with progressing hearing thresholds. On the neural level, McGurk illusions were negatively related to functional coupling between motor and auditory regions. Similarly, connectivity of the dorsal attention network to sensorimotor and primary motor cortices was reduced with increasing hearing loss. The same effect was obtained for connectivity between the salience network and visual cortex. Our findings suggest that with progressing untreated age-related hearing loss, functional coupling at rest declines, affecting connectivity of brain networks and areas associated with attentional, visual, sensorimotor and motor processes. Especially connectivity reductions between auditory and motor areas were related to stronger audio-visual integration found with increasing hearing loss.


Assuntos
Córtex Motor/diagnóstico por imagem , Rede Nervosa/fisiologia , Presbiacusia/diagnóstico , Córtex Visual/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Percepção Auditiva , Mapeamento Encefálico , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Vias Neurais , Percepção Visual
3.
Artigo em Russo | MEDLINE | ID: mdl-33095531

RESUMO

OBJECTIVE: To compare monopolar and bipolar mapping in point-by-point fashion by using of threshold amperage, frequency of positive motor responses and the number of muscles involved in response. MATERIAL AND METHODS: A prospective non-randomized study included 14 patients with supratentorial tumors who underwent surgery in 2018-2019. All neoplasms were localized within 2 cm from the motor cortex and pyramidal tract. Age of patients ranged from 25 to 74 years. There were 9 women and 5 men. Eight patients had malignant glioma (grade III - 4, grade IV - 4), 6 patients - meningioma. Motor functions were assessed in all patients before and after surgery (1, 7 days and 3 months later) by using of a 5-point scale. In addition to routine neurophysiological monitoring, comparative mono- and bipolar mapping of the pyramidal tract within the bed of excised tumor was carried out at the end of surgery. The points of motor responses were marked. Comparative analysis of mono- and bipolar stimulation at identical points included threshold amperage, frequency of positive motor responses and the number of muscles involved in response (leg, forearm, hand, facial muscles). Brain MRI was performed in early postoperative period for assessment of resection quality. RESULTS: There were 64 points of motor responses in 14 patients. The number of these points ranged from 2 to 8 per a patient (mean 5 points). Motor responses were recorded in 57 points during monopolar and bipolar stimulation, in other 7 points - only during monopolar stimulation. Amperage of monopolar stimulation was 3-15 mA, bipolar stimulation - 2.5-25 mA. Threshold amperage (7.37 mA for monopolar stimulation and 8.88 mA for bipolar stimulation; p=0.12), frequency of positive motor responses and the number of muscles involved in response (p=0.1 and p=0.73) were similar. Seven (50%) patients had neurological deterioration in early postoperative period (4 patients with glial tumors and 3 patients with meningiomas). At the same time, only 2 patients (14.3%) had persistent neurological deficit (both patients with infiltrative meningioma). According to postoperative MRI in T1+C mode, resection volume was 100% in 1 patient with contrast-enhanced glioma and 94% in another one. According to FLAIR MRI data, resection volume exceeded 70% in 2 patients with non-enhancing glioma and less than 70% in 2 patients. Meningioma resection volume was estimated according to postoperative T1+C MRI data and made up over 90% in 4 patients. CONCLUSION: Monopolar stimulation is a reliable method of pyramidal tract identification in supratentorial brain tumor surgery.


Assuntos
Transtorno Bipolar , Neoplasias Encefálicas , Neoplasias Meníngeas , Córtex Motor , Neoplasias Supratentoriais , Mapeamento Encefálico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Potencial Evocado Motor , Feminino , Humanos , Masculino , Monitorização Intraoperatória , Córtex Motor/diagnóstico por imagem , Estudos Prospectivos , Tratos Piramidais/diagnóstico por imagem , Neoplasias Supratentoriais/diagnóstico por imagem , Neoplasias Supratentoriais/cirurgia
4.
Neurology ; 95(17): e2318-e2330, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32999058

RESUMO

OBJECTIVE: To determine the effects of a 12-week home-based motor training telerehabilitation program in patients with subcortical stroke by combining motor function assessments and multimodality MRI analysis methods. METHODS: Fifty-two patients with stroke and hemiplegia were randomly assigned to either a home-based motor training telerehabilitation (TR) group or a conventional rehabilitation (CR) group for 12 weeks. The Fugl-Meyer assessment (FMA) for upper and lower extremities and the modified Barthel Index were used as primary outcomes. The secondary outcomes included resting-state functional connectivity (rsFC) between the bilateral M1 areas, gray matter volumes of the primary motor cortex (M1) areas, and white matter integrity of the corticospinal tract. Analysis of covariance was applied to examine the effects of the home-based motor training TR program on neural function recovery and brain plasticity. RESULTS: Compared with the CR group, the TR group showed significant improvement in the FMA (p = 0.011) and significantly increased M1-M1 rsFC (p = 0.031) at the end of the rehabilitation. The M1-M1 rsFC change was significantly positively correlated with the FMA change in the TR group (p = 0.018). CONCLUSION: This study showed a beneficial effect of the home-based motor training telerehabilitation program on motor function in patients with stroke, which was accompanied by enhanced interhemispheric functional connectivity of the M1 areas. We inferred that it is feasible, safe, and efficacious for patients with stroke to receive professional rehabilitation training at home. The combined use of imaging biomarkers should be encouraged in motor training clinical studies in patients with stroke. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with stroke with hemiplegia, home-based telerehabilitation compared to conventional rehabilitation significantly improves some motor function tests.


Assuntos
Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Telerreabilitação/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Tensor de Difusão , Avaliação da Deficiência , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/fisiopatologia , Serviços de Assistência Domiciliar , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiopatologia , Vias Neurais , Plasticidade Neuronal , Paresia/etiologia , Paresia/reabilitação , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/fisiopatologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral/instrumentação , Resultado do Tratamento
5.
Nat Commun ; 11(1): 5233, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067461

RESUMO

Decision-making via monitoring others' actions is a cornerstone of interpersonal exchanges. Although the ventral premotor cortex (PMv) and the medial prefrontal cortex (MPFC) are cortical nodes in social brain networks, the two areas are rarely concurrently active in neuroimaging, inviting the hypothesis that they are functionally independent. Here we show in macaques that the ability of the MPFC to monitor others' actions depends on input from the PMv. We found that delta-band coherence between the two areas emerged during action execution and action observation. Information flow especially in the delta band increased from the PMv to the MPFC as the biological nature of observed actions increased. Furthermore, selective blockade of the PMv-to-MPFC pathway using a double viral vector infection technique impaired the processing of observed, but not executed, actions. These findings demonstrate that coordinated activity in the PMv-to-MPFC pathway has a causal role in social action monitoring.


Assuntos
Macaca/fisiologia , Córtex Motor/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Mapeamento Encefálico , Tomada de Decisões , Macaca/psicologia , Masculino , Córtex Motor/química , Córtex Motor/diagnóstico por imagem , Vias Neurais , Córtex Pré-Frontal/química , Córtex Pré-Frontal/diagnóstico por imagem , Comportamento Social
6.
Sci Rep ; 10(1): 15844, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32985527

RESUMO

Why would people tell the truth when there is an obvious gain in lying and no risk of being caught? Previous work suggests the involvement of two motives, self-interest and regard for others. However, it remains unknown if these motives are related or distinctly contribute to (dis)honesty, and what are the neural instantiations of these motives. Using a modified Message Game task, in which a Sender sends a dishonest (yet profitable) or honest (less profitable) message to a Receiver, we found that these two motives contributed to dishonesty independently. Furthermore, the two motives involve distinct brain networks: the LPFC tracked potential value to self, whereas the rTPJ tracked potential losses to other, and individual differences in motives modulated these neural responses. Finally, activity in the vmPFC represented a balance of the two motives unique to each participant. Taken together, our results suggest that (dis)honest decisions incorporate at least two separate cognitive and neural processes-valuation of potential profits to self and valuation of potential harm to others.


Assuntos
Decepção , Motivação , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Feminino , Jogos Experimentais , Humanos , Masculino , Motivação/fisiologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiologia , Vias Neurais/fisiologia , Neuroimagem , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Autoimagem , Confiança/psicologia
7.
PLoS One ; 15(9): e0238318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881901

RESUMO

Knowledge on neural processing during complex non-stationary motion sequences of sport-specific movements still remains elusive. Hence, we aimed at investigating hemodynamic response alterations during a basketball slalom dribbling task (BSDT) using multi-distance functional near-infrared spectroscopy (fNIRS) in 23 participants (12 females). Additionally, we quantified how the brain adapts its processing as a function of altered hand use (dominant right hand (DH) vs. non-dominant left hand (NDH) vs. alternating hands (AH)) and pace of execution (slow vs. fast) in BSDT. We found that BSDT activated bilateral premotor cortex (PMC), supplementary motor cortex (SMA), primary motor cortex (M1) as well as inferior parietal cortex and somatosensory association cortex. Slow dominant hand dribbling (DHslow) evoked lower contralateral hemodynamic responses in sensorimotor regions compared to fast dribbling (DHfast). Furthermore, during DHslow dribbling, we found lower hemodynamic responses in ipsilateral M1 as compared to dribbling with alternating hands (AHslow). Hence, altered task complexity during BSDT induced differential hemodynamic response patterns. Furthermore, a correlation analysis revealed that lower levels of perceived task complexity are associated with lower hemodynamic responses in ipsilateral PMC-SMA, which is an indicator for neuronal efficiency in participants with better basketball dribbling skills. The present study extends previous findings by showing that varying levels of task complexity are reflected by specific hemodynamic response alterations even during sports-relevant motor behavior. Taken together, we suggest that quantifying brain activation during complex movements is a prerequisite for assessing brain-behavior relations and optimizing motor performance.


Assuntos
Encéfalo/fisiologia , Hemodinâmica , Adulto , Basquetebol , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Lateralidade Funcional/fisiologia , Hemoglobinas/química , Humanos , Masculino , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
8.
Psychiatry Res Neuroimaging ; 304: 111151, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-32738724

RESUMO

The neural mechanism of phantom limb pain (PLP) is related to the intense brain reorganization process implicating plasticity after deafferentation mostly in sensorimotor system. There is a limited understanding of the association between the sensorimotor system and PLP. We used a novel task-based functional magnetic resonance imaging (fMRI) approach to (1) assess neural activation within a-priori selected regions-of-interested (motor cortex [M1], somatosensory cortex [S1], and visual cortex [V1]), (2) quantify the cortical representation shift in the affected M1, and (3) correlate these changes with baseline clinical characteristics. In a sample of 18 participants, we found a significantly increased activity in M1 and S1 as well as a shift in motor cortex representation that was not related to PLP intensity. In an exploratory analyses (not corrected for multiple comparisons), they were directly correlated with time since amputation; and there was an association between increased activity in M1 with a lack of itching sensation and V1 activation was negatively correlated with PLP. Longer periods of amputation lead to compensatory changes in sensory-motor areas; and itching seems to be a protective marker for less signal changes. We confirmed that PLP intensity is not associated with signal changes in M1 and S1 but in V1.


Assuntos
Córtex Motor/fisiopatologia , Membro Fantasma/fisiopatologia , Córtex Somatossensorial/fisiopatologia , Adulto , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Motor/diagnóstico por imagem , Plasticidade Neuronal/fisiologia , Membro Fantasma/diagnóstico por imagem , Membro Fantasma/patologia , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/fisiopatologia , Córtex Somatossensorial/diagnóstico por imagem , Adulto Jovem
9.
Neuron ; 107(3): 580-589.e6, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32778224

RESUMO

To induce brain plasticity in humans, we casted the dominant upper extremity for 2 weeks and tracked changes in functional connectivity using daily 30-min scans of resting-state functional MRI (rs-fMRI). Casting caused cortical and cerebellar regions controlling the disused extremity to functionally disconnect from the rest of the somatomotor system, while internal connectivity within the disused sub-circuit was maintained. Functional disconnection was evident within 48 h, progressed throughout the cast period, and reversed after cast removal. During the cast period, large, spontaneous pulses of activity propagated through the disused somatomotor sub-circuit. The adult brain seems to rely on regular use to maintain its functional architecture. Disuse-driven spontaneous activity pulses may help preserve functionally disconnected sub-circuits.


Assuntos
Córtex Motor/diagnóstico por imagem , Plasticidade Neuronal/fisiologia , Restrição Física , Atividades Cotidianas , Moldes Cirúrgicos , Feminino , Lateralidade Funcional , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Motor/fisiologia , Destreza Motora/fisiologia , Força Muscular/fisiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Extremidade Superior
10.
PLoS One ; 15(8): e0236497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785230

RESUMO

When human movement is assisted or controlled with a muscle actuator, such as electrical muscle stimulation, a critical issue is the integration of such induced movement with the person's motion intention and how this movement then affects their motor control. Towards achieving optimal integration and reducing feelings of artificiality and enforcement, we explored perceptual simultaneity through electrical muscle stimulation, which involved changing the interval between intentional and induced movements. We report on two experiments in which we evaluated the ranges between detection and stimulus for perceptual simultaneity achievable with an electromyography-triggered electrical muscle stimulation system. We found that the peak range was approximately 80-160 ms, with the timing of perceptual simultaneity shifting according to different adaptation states. Our results indicate that perceptual simultaneity is controllable using this adaptation strategy.


Assuntos
Eletromiografia , Córtex Motor/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Adulto , Estimulação Elétrica , Mãos/fisiologia , Humanos , Masculino , Córtex Motor/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Visão Ocular/fisiologia , Adulto Jovem
11.
Sci Rep ; 10(1): 11217, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641706

RESUMO

The development of novel strategies to augment motor training success is of great interest for healthy persons and neurological patients. A promising approach is the combination of training with transcranial electric stimulation. However, limited reproducibility and varying effect sizes make further protocol optimization necessary. We tested the effects of a novel cerebellar transcranial alternating current stimulation protocol (tACS) on motor skill learning. Furthermore, we studied underlying mechanisms by means of transcranial magnetic stimulation and analysis of fMRI-based resting-state connectivity. N = 15 young, healthy participants were recruited. 50 Hz tACS was applied to the left cerebellum in a double-blind, sham-controlled, cross-over design concurrently to the acquisition of a novel motor skill. Potential underlying mechanisms were assessed by studying short intracortical inhibition at rest (SICIrest) and in the premovement phase (SICImove), intracortical facilitation at rest (ICFrest), and seed-based resting-state fMRI-based functional connectivity (FC) in a hypothesis-driven motor learning network. Active stimulation did not enhance skill acquisition or retention. Minor effects on striato-parietal FC were present. Linear mixed effects modelling identified SICImove modulation and baseline task performance as the most influential determining factors for predicting training success. Accounting for the identified factors may allow to stratify participants for future training-based interventions.


Assuntos
Ritmo Gama/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Cerebelo/diagnóstico por imagem , Cerebelo/fisiologia , Conectoma , Estudos Cross-Over , Método Duplo-Cego , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiologia , Resultado do Tratamento , Adulto Jovem
12.
Sci Rep ; 10(1): 11504, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32661345

RESUMO

Phantom limb pain (PLP) has been associated with reorganization in primary somatosensory cortex (S1) and preserved S1 function. Here we examined if methodological differences in the assessment of cortical representations might explain these findings. We used functional magnetic resonance imaging during a virtual reality movement task, analogous to the classical mirror box task, in twenty amputees with and without PLP and twenty matched healthy controls. We assessed the relationship between task-related activation maxima and PLP intensity in S1 and motor cortex (M1) in individually-defined or group-conjoint regions of interest (ROI) (overlap of task-related activation between the groups). We also measured cortical distances between both locations and correlated them with PLP intensity. Amputees compared to controls showed significantly increased activation in M1, S1 and S1M1 unrelated to PLP. Neural activity in M1 was positively related to PLP intensity in amputees with PLP when a group-conjoint ROI was chosen. The location of activation maxima differed between groups in S1 and M1. Cortical distance measures were unrelated to PLP. These findings suggest that sensory and motor maps differentially relate to PLP and that methodological differences might explain discrepant findings in the literature.


Assuntos
Amputados , Dor/fisiopatologia , Membro Fantasma/fisiopatologia , Córtex Somatossensorial/fisiopatologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiopatologia , Plasticidade Neuronal/fisiologia , Dor/diagnóstico por imagem , Membro Fantasma/diagnóstico por imagem , Córtex Somatossensorial/diagnóstico por imagem
13.
J Comput Assist Tomogr ; 44(4): 533-539, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697523

RESUMO

PURPOSE: The purpose of this study was to investigate the differences of gray matter volume (GMV) alteration patterns between hemodialysis with restless legs syndrome (HD-RLS) and hemodialysis without restless legs syndrome (HD-nRLS) patients using voxel-based morphometry. METHODS: Twenty-three HD-RLS patients, 27 HD-nRLS patients, and 27 age-, sex-, and education-matched healthy controls were included in this study. One-way analysis of covariance and post hoc analyses were used to assess differences in GMV, demographics, and clinical data among the 3 groups. Pearson correlation analysis was conducted between altered GMV in the HD-RLS group and clinical data. RESULTS: Compared with HD-nRLS patients, HD-RLS patients showed decreased GMV in the left primary motor cortex (false discovery rate corrected, P < 0.05). Compared with the healthy controls, both HD subgroups (ie, those with and without RLS) exhibited consistent GMV changes, including decreased GMV in the bilateral anterior cingulate and paracingulate gyrus and left middle temporal gyrus (false discovery rate corrected, P < 0.05). The GMV values in the left precentral gyrus were negatively correlated with the RLS rating scores (r = 0.2138, P = 0.0263). CONCLUSIONS: This abnormal decreased GMV in the sensorimotor cortex provides evidence for a sensory processing disorder in RLS that may be involved in the pathogenesis of RLS in HD patients.


Assuntos
Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Diálise Renal/efeitos adversos , Síndrome das Pernas Inquietas/diagnóstico por imagem , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Tamanho do Órgão , Síndrome das Pernas Inquietas/complicações
14.
NeuroRehabilitation ; 46(4): 483-489, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508339

RESUMO

BACKGROUND: Robot-assisted gait training (RAGT) can improve walking ability after stroke but the underlying mechanisms are unknown. OBJECTIVE: We evaluated the changes in the injured brain after RAGT and compared the effects of early start and late start of RAGT. METHODS: Eleven patients with hemiplegia after stroke undergoing inpatient rehabilitation were examined within 3 months of stroke onset and were randomly assigned into two groups. Group 1 started RAGT with conventional physiotherapy immediately after enrollment, whereas Group 2 underwent conventional physiotherapy for 4 weeks before starting RAGT. We acquired diffusion tensor imaging data after enrollment and at 4 and 8 weeks after treatment. Fractional anisotropy (FA) and mean diffusivity (MD) maps were used to analyze the neural changes. RESULTS: Repeated measures analysis of variance of the data at 4 weeks after treatment showed a significant interaction between time and groups (RAGT versus control) for the FA and MD values in the non-lesioned hemisphere, indicating that the non-lesioned hemisphere was significantly reorganized by RAGT compared with conventional physiotherapy. Analysis of the data at 8 weeks after treatment showed a significant interaction between time and groups (early and late start of RAGT) for the MD values in the motor-related areas bilaterally, indicating that early start of RAGT significantly accelerated bi-hemispheric reorganization as compared with late start of RAGT. CONCLUSIONS: Our findings indicate that RAGT can facilitate reorganization in the intact superior temporal, cingulate, and postcentral gyri. Furthermore, early start of RAGT can accelerate bi-hemispheric reorganization in the motor-related brain regions.


Assuntos
Terapia por Exercício/métodos , Marcha , Córtex Motor/diagnóstico por imagem , Robótica/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Adulto , Idoso , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Psychiatry Res Neuroimaging ; 303: 111125, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32585576

RESUMO

Functional movement disorders (FMD) are a common source of disability in neurology.While treatment of FMD can reduce motor severity and disability, the neural mechanisms implicated in such a response remain unclear. We aimed to investigate neural changes in patients with FMD after a one-week multidisciplinary motor retraining (MoRe) treatment program. Fourteen FMD patients completed an emotional Go/No-Go fMRI task before and after MoRe treatment. Standardized pre- and post-treatment videos were rated for motor severity by a blinded reviewer using the psychogenic movement disorder rating scale (PMDRS). PMDRS scores before and after treatment were used for whole-brain regression. PMDRS scores were significantly reduced after MoRe treatment. Worse severity prior to treatment was associated with greater primary motor cortex (M1) activation at baseline and a larger response to treatment. Globally, increased connectivity between bilateral amygdala and premotor regions was observed following treatment. Lower post-treatment PMDRS scores were associated with increased connectivity between amygdala and ventromedial prefrontal cortex, whereas higher post-treatment PMDRS scores (and poorer treatment response) were associated with increased connectivity between amygdala and M1. Motor retraining in FMD may reorganize activity and connectivity in emotion processing and motor planning networks, with shifts in amygdala connectivity from posterior to frontal/prefrontal regions.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Imagem por Ressonância Magnética/tendências , Córtex Motor/diagnóstico por imagem , Transtornos dos Movimentos/diagnóstico por imagem , Transtornos dos Movimentos/reabilitação , Córtex Pré-Frontal/diagnóstico por imagem , Adulto , Tonsila do Cerebelo/fisiopatologia , Feminino , Humanos , Pacientes Internados , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Transtornos dos Movimentos/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Estimulação Luminosa/métodos , Projetos Piloto , Córtex Pré-Frontal/fisiopatologia , Desempenho Psicomotor/fisiologia , Centros de Reabilitação/tendências
16.
Stroke ; 51(7): 2170-2178, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32568657

RESUMO

BACKGROUND AND PURPOSE: Motor deficit is the most common disability after stroke, and early prediction of motor outcome is critical for early interventions. Here, we constructed a fine map of the corticospinal tract (CST) for early prediction of motor outcome and for understanding the secondary brain changes after subcortical stroke. METHODS: Diffusion spectrum imaging data from 50 healthy adults were used to reconstruct fine maps of CST with different origins, including primary motor area (M1), primary sensory area (S1), premotor cortex, and supplementary motor area (SMA). Their diffusion properties correlated with motor functions in healthy adults. The impacts of the impairments of different CST on motor outcomes and on structural and functional changes of brain were investigated in 136 patients with subcortical stroke by combining CST damage-symptom association study and voxel-based lesion-symptom mapping. RESULTS: In healthy adults, the isotropy of M1 fiber correlated with walking endurance and that of SMA fiber with motor dexterity. In chronic stroke patients, the integrity of M1 and SMA fibers showed the most significant correlation with motor deficits. The percentage of early damage of M1 and SMA fibers correlated with that of chronic motor deficits. Voxel-based lesion-symptom mapping revealed that acute stroke lesions in the bilateral M1 and right SMA fibers were associated with chronic motor deficits. The early damage of M1 fiber negatively correlated with the integrity of M1-M1 fiber, and the early damage of SMA fiber negatively correlated with gray matter volume of the contralateral cerebellum in the chronic stage. CONCLUSIONS: The CST that originated from the M1 and SMA are closely associated with motor outcomes and brain structural changes, and the fine maps of CST from these 2 cortical areas are useful in assessing and predicting long-term motor outcome in patients with subcortical stroke.


Assuntos
Mapeamento Encefálico/métodos , Atividade Motora/fisiologia , Córtex Motor/fisiopatologia , Tratos Piramidais/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Neuroimagem/métodos , Tratos Piramidais/diagnóstico por imagem , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/complicações
17.
Sci Rep ; 10(1): 7326, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355238

RESUMO

Effective interventions have demonstrated the ability to improve motor function by reengaging ipsilesional resources, which appears to be critical and feasible for hand function recovery even in individuals with severe chronic stroke. However, previous studies focus on changes in brain activity related to motor execution. How changes in motor preparation may facilitate these changes at motor execution is still unclear. To address this question, 8 individuals with severe chronic hemiparetic stroke participated in a device-assisted intervention for seven weeks. We then quantified changes in both coupling between regions during motor preparation and changes in topographical cortical activity at motor execution for both hand opening in isolation and together with the shoulder using high-density EEG. We hypothesized that intervention-induced changes in cortico-cortico interactions during motor preparation would lead to changes in activity at motor execution specifically towards an increased reliance on the ipsilesional hemisphere. In agreement with this hypothesis, we found that, following the intervention, individuals displayed a reduction in coupling from ipsilesional M1 to contralesional M1 within gamma frequencies during motor preparation for hand opening. This was followed by a reduction in activity in the contralesional primary sensorimotor cortex during motor execution. Similarly, during lifting and opening, a shift to negative coupling within ipsilesional M1 from gamma to beta frequencies was accompanied by an increase in ipsilesional primary sensorimotor cortex activity following the intervention. Together, these results show that intervention-induced changes in coupling within or between motor regions during motor preparation may affect cortical activity at execution.


Assuntos
Córtex Motor/fisiologia , Paresia/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Idoso , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Lateralidade Funcional , Mãos/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Modelos Neurológicos , Córtex Motor/diagnóstico por imagem , Destreza Motora , Vias Neurais/fisiopatologia , Recuperação de Função Fisiológica , Córtex Sensório-Motor/fisiopatologia , Acidente Vascular Cerebral/diagnóstico por imagem
18.
Sci Rep ; 10(1): 7528, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32372021

RESUMO

Deep brain stimulation (DBS) has been shown to be an effective treatment for movement disorders and it is now being extended to the treatment of psychiatric disorders. Functional magnetic resonance imaging (fMRI) studies indicate that DBS stimulation targets dependent brain network effects, in networks that respond to stimulation. Characterizing these patterns is crucial for linking DBS-induced therapeutic and adverse effects. Conventional DBS-fMRI, however, lacks the sensitivity needed for decoding multidimensional information such as spatially diffuse patterns. We report here on the use of a multivariate pattern analysis (MVPA) to demonstrate that stimulation of three DBS targets (STN, subthalamic nucleus; GPi, globus pallidus internus; NAc, nucleus accumbens) evoked a sufficiently distinctive blood-oxygen-level-dependent (BOLD) activation in swine brain. The findings indicate that STN and GPi evoke a similar motor network pattern, while NAc shows a districted associative and limbic pattern. The findings show that MVPA could be effectively applied to overlapping or sparse BOLD patterns which are often found in DBS. Future applications are expected employ MVPA fMRI to identify the proper stimulation target dependent brain circuitry for a DBS outcome.


Assuntos
Encéfalo/diagnóstico por imagem , Estimulação Encefálica Profunda , Processamento de Imagem Assistida por Computador/métodos , Sistema Límbico/diagnóstico por imagem , Córtex Motor/diagnóstico por imagem , Reconhecimento Automatizado de Padrão , Animais , Mapeamento Encefálico , Eletrodos , Globo Pálido , Imagem por Ressonância Magnética , Análise Multivariada , Núcleo Accumbens/metabolismo , Oxigênio/metabolismo , Suínos
19.
Sci Rep ; 10(1): 7851, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398669

RESUMO

A simple motor behaviour or a more complex behaviour is the result of the neural activity of those neural networks responsible for the behaviour. To understand how the network activity is transformed into human behaviours, it is necessary to identify task-specific networks and analyse the dynamic network activity that changes with time. Here we report a novel task-fMRI technique to identify task-specific networks and analyse their dynamic activity. Nine subjects participated in a task-fMRI study in which the subjects were cued to perform three different tasks of word-reading, pattern-viewing and finger-tapping. A functional area of unitary pooled activity (FAUPA) is defined as an area in which the temporal variation of the activity is the same across the entire area, and a task-associated FAUPA plays the role of a functional unit for the task. A novel method is presented to (1) identify FAUPAs that are associated with each task as well as their functional groupings; (2) identify the three task-specific networks; and (3) analyse the network activity from trial to trial. Task-associated FAUPAs were identified for each task and each subject. A task-specific large-scale neural network across the whole brain consisted of all FAUPAs that were activated each time the task was performed, and all three task-specific networks were identified for each individual subject. The temporal changes of activation and functional connectivity of the FAUPAs within each network from trial to trial characterized the dynamic activity of the network. The results demonstrated a one-to-one relation between the network activity and the task performance from trial to trial, offering a means of testing the causal relationship between network activity and human task performance by systematically manipulating task performance and measuring corresponding network activity change.


Assuntos
Encéfalo/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Dedos/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiologia , Movimento , Córtex Somatossensorial/diagnóstico por imagem , Córtex Somatossensorial/fisiologia , Adulto Jovem
20.
World Neurosurg ; 140: 303-307, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32428719

RESUMO

BACKGROUND: Malformations of cortical development (MCDs) often result in mental retardation, intractable epilepsy, neurodevelopmental delay, and contralateral hemiparesis. We describe herein a rare patient with MCD who had developed normally in spite of diffuse hemispheric anomaly of the brain. CASE DESCRIPTION: We report a left-handed 20-year-old healthy man. A magnetic resonance image scan revealed congenital left cerebral hemispheric dysplasia and deficit of the normal anatomical primary motor cortices although he was normally developed without hemiparesis nor aphasia. Diffusion tensor tractography showed unusual fiber radiation from the left cerebral peduncle to the much more rostral and lateral cerebral cortices compared with normal anatomy. Right finger flexion-extension task showed activation in that area on functional magnetic resonance imaging. CONCLUSIONS: Even in a congenital hemispheric dysplasia, the contralateral fine finger movement may still depend on the dysplastic hemisphere. On the other hand, speech and the other gross movements including leg, foot, and arm can be compensated with the ipsilateral normal cerebral cortices.


Assuntos
Dedos/fisiologia , Lateralidade Funcional/fisiologia , Córtex Motor/fisiopatologia , Movimento/fisiologia , Imagem de Tensor de Difusão , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Motor/diagnóstico por imagem , Adulto Jovem
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