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1.
Medicine (Baltimore) ; 100(3): e24302, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33546056

RESUMO

RATIONALE: Cortical deafness is a rare auditory dysfunction caused by damage to brain auditory networks. The aim was to report alterations of functional connectivity in intrinsic auditory, motor, and sensory networks in a cortical deafness patient. PATIENT CONCERNS: A 41-year-old woman suffered a right putaminal hemorrhage. Eight years earlier, she had suffered a left putaminal hemorrhage and had minimal sequelae. She had quadriparesis, imbalance, hypoesthesia, and complete hearing loss. DIAGNOSES: She was diagnosed with cortical deafness. After 6 months, resting-state functional magnetic resonance imaging (rs-fMRI) and diffuse tensor imaging (DTI) were performed. DTI revealed that the acoustic radiation was disrupted while the corticospinal tract and somatosensory track were intact using deterministic tracking methods. Furthermore, the patient showed decreased functional connectivity between auditory and sensorimotor networks. INTERVENTIONS: The patient underwent in-patient stroke rehabilitation therapy for 2 months. OUTCOMES: Gait function and ability for activities of daily living were improved. However, complete hearing impairment persisted in 6 months after bilateral putaminal hemorrhagic stroke. LESSONS: Our case report seems to suggest that functional alterations of spontaneous neuronal activity in auditory and sensorimotor networks are related to motor and sensory impairments in a patient with cortical deafness.


Assuntos
Córtex Auditivo/anormalidades , Perda Auditiva Central/etiologia , Rede Nervosa/anormalidades , Córtex Sensório-Motor/anormalidades , Adulto , Córtex Auditivo/fisiopatologia , Feminino , Perda Auditiva Central/fisiopatologia , /fisiopatologia , Humanos , Testes de Estado Mental e Demência , Rede Nervosa/fisiopatologia , Hemorragia Putaminal/complicações , Hemorragia Putaminal/fisiopatologia , Córtex Sensório-Motor/fisiopatologia
2.
JAMA Netw Open ; 3(3): e201184, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32186744

RESUMO

Importance: Developmental coordination disorder (DCD) is a motor impairment that significantly interferes with activities of daily living. Little is known about the cause of DCD and how it develops, making it difficult to understand why children with DCD struggle in learning motor skills and to determine the best intervention to optimize function. Objective: To characterize white matter differences using diffusion tensor imaging in children with and without DCD. Design, Setting, and Participants: This cross-sectional study collected diffusion tensor imaging data at BC Children's Hospital Research Institute in Vancouver, British Columbia, Canada, from September 2014 to January 2017. Using a sample of convenience, children with DCD and children without DCD aged 8 to 12 years underwent magnetic resonance imaging. Data analysis was conducted from January 2017 to January 2020. Main Outcomes and Measures: The main outcome measures were diffusion parameters, including fractional anisotropy and mean, axial, and radial diffusivity, which are thought to provide an indirect measure of white matter microstructure. Tract-based spatial statistics, a voxelwise statistical analysis of diffusion parameters, were conducted using a 2-group comparison design matrix with age and attention as covariates. Results: Thirty children without DCD (mean [SD] age, 9.9 [1.4] years; 21 [70%] boys) and 31 children with DCD (mean [SD] age, 10.1 [1.2] years; 26 [84%] boys) were included in the study. Compared with children without DCD, children with DCD were characterized by significantly lower fractional anisotropy and axial diffusivity in regions of white matter pathways associated with motor and sensorimotor processing, including the corticospinal tract (fractional anisotropy: mean [SD], 0.54 [0.03] vs 0.51 [0.03]; P < .001; axial diffusivity: mean [SD], 0.13 [0.98] vs 0.12 [0.46]; P = .01), posterior thalamic radiation at the retrolenticular part of the internal capsule (axial diffusivity: mean [SD], 0.14 [0.57] vs 0.14 [0.44]; P = .01), and cerebellar pathways (eg, superior cerebellar peduncle, fractional anisotropy: mean [SD], 0.49 [0.05] vs 0.46 [0.03]; P = .03; axial diffusivity: mean [SD], 0.14 [0.66] vs 0.14 [0.63]; P = .009). There were no significant differences in mean diffusivity and radial diffusivity between children with and without DCD. Conclusions and Relevance: These findings suggest that children with DCD show significant brain differences in motor and sensorimotor white matter pathways compared with children without DCD. The pattern of diffusion parameters in children with DCD suggests that axonal development may be disrupted in this neurodevelopmental disorder.


Assuntos
Imagem de Tensor de Difusão , Transtornos das Habilidades Motoras/patologia , Substância Branca/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Colúmbia Britânica , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Transtornos das Habilidades Motoras/diagnóstico por imagem , Transtornos das Habilidades Motoras/fisiopatologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/patologia , Córtex Sensório-Motor/fisiopatologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiopatologia
3.
PLoS One ; 15(3): e0230603, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187207

RESUMO

Sense of agency refers to the feeling of being in control of one's actions. Previous research has demonstrated that sense of agency is produced through the sensorimotor system, which is involved in comparing internal predictions with sensory feedback in motor control. Therefore, sensorimotor deficits might impair agency through a sensorimotor system malfunction. The present study examined this hypothesis by investigating post-stroke patients who had suffered a subcortical stroke that damaged regions associated with sensorimotor function. To examine agency judgments with respect to motor control, we adopted a self-other attribution task and applied it to post-stroke patients. Participants traced a horizontal straight line and received visual feedback through a cursor on a monitor. The cursor movement reflected either the participants' actual movement or the movement of an "other" that had been previously recorded. Participants judged whether the cursor movement reflected their own movement (self) or an other's movement while they engaged in four cycles of the horizontal tracing movement. After each trial, participants reported their self-other judgment on a nine-point scale. Post-stroke patients completed the experiment with their paretic as well as their non-paralyzed upper limbs. Compared to healthy controls, patients made significantly more self-attributions of others' movements. Interestingly, such misattributions were observed in the patients' performance using both paretic and non-paralyzed upper limbs. These results suggest that post-stroke patients with sensorimotor deficits form misattributions that cannot be explained solely by the sensorimotor system's role in motor control. We discuss these misattributions in post-stroke patients in terms of cue integration theory.


Assuntos
Julgamento , Córtex Sensório-Motor/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Desempenho Psicomotor
4.
Exp Brain Res ; 238(1): 205-220, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31834452

RESUMO

We tested the hypothesis that injury to frontoparietal sensorimotor areas causes greater initial impairments in performance and poorer recovery of ipsilesional dexterous hand/finger movements than lesions limited to frontal motor areas in rhesus monkeys. Reaching and grasping/manipulation of small targets with the ipsilesional hand were assessed for 6-12 months post-injury using two motor tests. Initial post-lesion motor skill and long-term recovery of motor skill were compared in two groups of monkeys: (1) F2 group-five cases with lesions of arm areas of primary motor cortex (M1) and lateral premotor cortex (LPMC) and (2) F2P2 group-five cases with F2 lesions + lesions of arm areas of primary somatosensory cortex and the anterior portion of area 5. Initial post-lesion reach and manipulation skills were similar to or better than pre-lesion skills in most F2 lesion cases in a difficult fine motor task but worse than pre-lesion skill in most F2P2 lesion cases in all tasks. Subsequently, reaching and manipulation skills improved over the post-lesion period to higher than pre-lesion skills in both groups, but improvements were greater in the F2 lesion group, perhaps due to additional task practice and greater ipsilesional limb use for daily activities. Poorer and slower post-lesion improvement of ipsilesional upper limb motor skill in the F2P2 cases may be due to impaired somatosensory processing. The persistent ipsilesional upper limb motor deficits frequently observed in humans after stroke are probably caused by greater subcortical white and gray matter damage than in the localized surgical injuries studied here.


Assuntos
Mãos/fisiopatologia , Córtex Motor/lesões , Córtex Motor/fisiopatologia , Destreza Motora/fisiologia , Córtex Sensório-Motor/lesões , Córtex Sensório-Motor/fisiopatologia , Animais , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Feminino , Macaca mulatta , Masculino
6.
Acta Neurochir (Wien) ; 162(2): 261-269, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31781997

RESUMO

BACKGROUND: Electrical cortical stimulation is shown effective in treating patients with drug-resistant epilepsy. We demonstrated how detailed procedures of pre- and intra-operative planning of cortical stimulation implantation may influence the results of seizure reduction rate. METHODS: To confirm the precision of subdural grids covering the epileptogenic foci in the eloquent regions, pre- and intra-operative video-electroencephalography (VEEG) were performed in patients with drug-resistant epilepsy during a 4-day 24-h monitoring. The localization of the grid was determined via 3D reconstruction imaging of subdural electrodes co-registered onto the patient's cortex. A final quadripolar lead in cyclic stimulation mode was then placed and secured on the target cortex area. Post-operative 3D CT ensured the accurate location of stimulation lead without any misplacement. Bipolar cyclic stimulation and post-implantation VEEG were performed for 7 days. Patients were discharged and followed up regularly for parameters adjustment and recording of seizure outcomes. RESULTS: Eight patients received chronic cortical stimulation implantations between February 2003 and December 2017. The mean age of these patients was 21.1 years old and the average post-operative follow-up was 77.3 months. Comparisons of their seizure frequency at baseline and during the postoperative period revealed a mean reduction in seizures of 60.4% at the first year and 65.6% at the second year. CONCLUSIONS: Pre-surgical planning enhanced the accuracy of electrode placement and led to a favorable seizure reduction rate. Our report confirms that electrical cortical stimulation with detailed implantation procedures is safe and effective for patients with drug-resistant epilepsy originating from eloquent cortex.


Assuntos
Estimulação Encefálica Profunda/métodos , Epilepsia Resistente a Medicamentos/terapia , Adolescente , Adulto , Estimulação Encefálica Profunda/instrumentação , Eletrodos Implantados , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Córtex Sensório-Motor/fisiopatologia , Resultado do Tratamento
7.
Neurol Res ; 42(1): 39-46, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31847728

RESUMO

Objective: Comorbidity of erectile dysfunction (ED) and epilepsy is not rare. Tadalafil is widely used in the treatment of ED and shows its effect by increasing nitric oxide (NO) level. Previous studies demonstrated that ED treatment drugs increased epileptiform activity in clinical studies and various experimental epilepsy models. Therefore, it is important to know whether an ED treatment drug has proconvulsion or anticonvulsant properties. This study was designed to demonstrate the effect of tadalafil and NO agonist sodium nitroprusside during penicillin-induced seizures in rats. The experimental penicillin epilepsy model is preferred in clinical studies of partial epilepsy.Methods: A single dose of penicillin (500 units) intracortical (i.c.) injection into the left sensorimotor cortex induced epileptiform activity. In the first set of experiments, tadalafil (20 mg/kg/intraperitoneal [i.p.]) and sodium nitroprusside (50 µg/intracerebroventricular [µg/i.c.v]) were administered 30 min after penicillin injection.In the second set of experiments, tadalafil (i.p) was administered 30 min after penicillin injection and sodium nitroprusside was administered simultaneously with the tadalafil injection.Results: Tadalafil, sodium nitroprusside and tadalafil+sodium nitroprusside groups decreased the frequency and amplitude of epileptiform activity in rats. Spike frequency of all groups decreased significantly 10 min after the administration and this decrease continued for 180 min. The mean amplitude of epileptiform activity significantly decreased 120 min after penicillin application in tadalafil or sodium nitroprusside applications. But this decrease was observed 110 min after tadalafil+sodium nitroprusside combined application.Conclusion: Data from the present study indicate that tadalafil has an anticonvulsion effect against penicillin-induced epileptiform activity in rats.


Assuntos
Óxido Nítrico/agonistas , Nitroprussiato/administração & dosagem , Penicilinas/toxicidade , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Tadalafila/administração & dosagem , Animais , Eletrocorticografia/efeitos dos fármacos , Eletrocorticografia/métodos , Injeções Intraventriculares , Masculino , Doadores de Óxido Nítrico/administração & dosagem , Ratos , Ratos Wistar , Convulsões/fisiopatologia , Córtex Sensório-Motor/efeitos dos fármacos , Córtex Sensório-Motor/fisiopatologia , Resultado do Tratamento , Vasodilatadores/administração & dosagem
8.
Neurobiol Aging ; 85: 104-112, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31732217

RESUMO

Impairments in fine and gross motor function, coordination, and balance in early development are common in autism spectrum disorders (ASDs). It is unclear whether these deficits persist into adulthood and whether they may be exacerbated by additional motor problems that often emerge in typical aging. We assessed motor skills and used resting-state functional magnetic resonance imaging to study intrinsic functional connectivity of the sensorimotor network in 40- to 65-year-old adults with ASDs (n = 17) and typically developing matched adults (n = 19). Adults with ASDs scored significantly lower on assessments of motor skills compared with an age-matched group of typical control adults. In addition, functional connectivity of the sensorimotor system was reduced and the pattern of connectivity was more heterogeneous in adults with ASDs. A negative correlation between functional connectivity of the motor system and motor skills, however, was only found in the typical control group. Findings suggest behavioral impairment and atypical brain organization of the motor system in middle-age adults with ASDs, accompanied by pronounced heterogeneity.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Encéfalo/fisiopatologia , Transtornos das Habilidades Motoras/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Adulto , Idoso , Transtorno do Espectro Autista/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos das Habilidades Motoras/complicações
9.
Curr Vasc Pharmacol ; 18(1): 50-56, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30156161

RESUMO

BACKGROUND: Cardiovascular autonomic neuropathy (CAN) and distal symmetrical sensorimotor polyneuropathy (DSPN) are serious microvascular complications of diabetes mellitus (DM). Their simultaneous development remains disputable. The aim of the present study was to examine the correlation between CAN and the presence/severity of DSPN in DM. METHODS: Subjects with type 1 (group A: n=51; mean age 40.4 years) and type 2 DM (group B: n=153; mean age 64.6 years) were studied. Evaluation of DSPN was based on neuropathy disability score. Assessment of CAN was based on the battery of 4 standardized cardiovascular autonomic function tests. RESULTS: In group A, patients with moderate/severe DSPN exhibited a 12-fold higher likelihood of CAN in univariate analysis (p=0.035). However, significance was lost after adjustment for gender, age, DM duration, and haemoglobin A1c. In group A, likelihood for CAN did not correlate with the presence of mild DSPN in univariate and multivariate analysis. In group B, likelihood of CAN was similar in patients with mild and in those with moderate/severe DSPN compared with patients without DSPN in univariate and multivariate analysis. In between group comparison CAN was similarly distributed in the 2 groups (p for interaction=0.367), in patients with no, mild and moderate/severe DSPN. CONCLUSION: CAN does not always co-exist with degrees of DSPN, ranging from mild to moderate/ severe and is similarly distributed in T1DM and T2DM patients with mild and moderate/severe DSPN and in patients without DSPN.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Sistema Cardiovascular/inervação , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/etiologia , Neuropatias Diabéticas/etiologia , Córtex Sensório-Motor/fisiopatologia , Adulto , Idoso , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/fisiopatologia , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
10.
Physiother Theory Pract ; 36(1): 142-156, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29889597

RESUMO

Purpose: To assess the feasibility and clinical impact of brain-targeted treatment (BT; aiming to target sensorimotor processing) in knee osteoarthritis patients attending tertiary care. Methods: Randomized replicated case series. The study involved three phases, each of 2 weeks duration: (1) no-treatment phase; (2) BT phase (left/right judgments and touch discrimination training); and (3) usual care (education, strengthening, and stretching training). Primary outcomes were: timely recruitment; number of participants completing the interventions; treatment compliance and barriers; follow-up rates; and treatment impact on pain and function. Fear-avoidance beliefs and clinical measures of cortical body representation (tactile acuity and left/right judgment performance) were secondary outcomes. Results: A total of 5% (19/355) of all assessed patients were eligible to participate and of these, 58% (11/19) agreed to participate. Ten patients completed the study, and 9 were successfully followed up, with treatment compliance varying between interventions. Compliance was poor for the touch discrimination component of BT. No significant effects were observed for pain relief or knee function after any treatment. A positive impact of treatment was found for fear-avoidance beliefs (usual care vs. washout, p = 0.007; BT vs. washout, p = 0.029) and left/right judgment accuracy (usual care vs. washout; p = 0.006). Conclusions: Clear barriers were identified to implementing BT in tertiary care for knee osteoarthritis. Access to all available services (especially the use of interpreters), and treatment options that do not require additional assistance to perform (e.g., touch discrimination training) represent the main lessons learned.


Assuntos
Imagens, Psicoterapia/métodos , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/terapia , Manejo da Dor/métodos , Córtex Sensório-Motor/fisiopatologia , Idoso , Avaliação da Deficiência , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Atenção Terciária à Saúde
11.
Elife ; 82019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31820736

RESUMO

Speaking is a sensorimotor behavior whose neural basis is difficult to study with single neuron resolution due to the scarcity of human intracortical measurements. We used electrode arrays to record from the motor cortex 'hand knob' in two people with tetraplegia, an area not previously implicated in speech. Neurons modulated during speaking and during non-speaking movements of the tongue, lips, and jaw. This challenges whether the conventional model of a 'motor homunculus' division by major body regions extends to the single-neuron scale. Spoken words and syllables could be decoded from single trials, demonstrating the potential of intracortical recordings for brain-computer interfaces to restore speech. Two neural population dynamics features previously reported for arm movements were also present during speaking: a component that was mostly invariant across initiating different words, followed by rotatory dynamics during speaking. This suggests that common neural dynamical motifs may underlie movement of arm and speech articulators.


Assuntos
Córtex Motor/fisiopatologia , Rede Nervosa/fisiopatologia , Quadriplegia/fisiopatologia , Fala/fisiologia , Algoritmos , Braço/fisiopatologia , Interfaces Cérebro-Computador , Eletrocorticografia , Mãos/fisiopatologia , Humanos , Lábio/fisiopatologia , Modelos Neurológicos , Movimento/fisiologia , Córtex Sensório-Motor/fisiopatologia , Língua/fisiopatologia
12.
Neurorehabil Neural Repair ; 33(12): 1018-1028, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31679451

RESUMO

Background. The neuroimaging literature on cerebral palsy (CP) has predominantly focused on identifying the structural aberrations (eg, fiber track integrity), with very few studies examining neural activity within the key networks that serve the production of hand movements. Objective. We aimed to start to fill this knowledge gap by using magnetoencephalographic brain imaging to quantify the temporal dynamics of the sensorimotor oscillations during a hand motor action. Methods: Children with CP (n = 12; MACS [Manual Abilities Classification System] levels I-III) and typically developing (TD) children (n = 26) performed an arrow-based version of the Eriksen flanker task where a button press was performed with either the second or third digit of the right hand depending on the arrow's direction. Results: Overall, the children with CP were less accurate and had slower reaction times compared with the TD children. These behavioral differences were closely linked with aberrant sensorimotor cortical oscillations seen in the children with CP. Compared with the TD children, the children with CP had a weaker gamma (68-82 Hz) response during motor execution and a weaker post-movement beta rebound (PMBR; 14-26 Hz) response on movement termination. Moreover, we observed a significant correlation between the amplitude of the gamma and PMBR with reaction time, with weaker gamma and PMBR responses being linked with slower reaction times. Conclusions: Overall, these results suggest that aberrations in motor-related gamma and beta cortical oscillations are associated with the impaired hand motor actions seen in children with CP.


Assuntos
Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/psicologia , Atividade Motora , Córtex Sensório-Motor/fisiopatologia , Adolescente , Adulto , Ondas Encefálicas , Criança , Feminino , Mãos/fisiopatologia , Humanos , Magnetoencefalografia , Masculino , Tempo de Reação , Adulto Jovem
13.
Exp Brain Res ; 237(12): 3175-3183, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31595331

RESUMO

Although no damage occurs in the brains of individuals with spinal cord injury, structural and functional reorganization occurs in the sensorimotor cortex because of the deafferentation of afferent signal input from below the injury level. This brain reorganization that is specific to individuals with spinal cord injury is speculated to contribute to the improvement of the motor function of the remaining upper limbs. However, no study has investigated in detail the motor function above the injury level. To clarify this, we designed an experiment using the handgrip force steadiness task, which is a popular technique for evaluating motor function as the index of the variability of common synaptic input to motoneurons. Fourteen complete spinal cord injury (cSCI) individuals in the chronic phase, fifteen individuals with lower limb disabilities, and twelve healthy controls participated in the study. We clarified that the force steadiness in the cSCI group was significantly higher than that in the control groups, and that sports years were significantly correlated with this steadiness. Furthermore, multiple analyses revealed that force steadiness was significantly predicted by sports years. These results suggest that brain reorganization after spinal cord injury can functionally affect the remaining upper limb motor function. These findings may have implications in the clinical rehabilitation field, such as occupational rehabilitation of the upper limbs. They also indicate that individuals with complete spinal cord injury, based on their enhanced force adjustment skills, would excel at fine motor tasks such as manufacturing and handicrafts.


Assuntos
Força da Mão/fisiologia , Atividade Motora/fisiologia , Plasticidade Neuronal/fisiologia , Córtex Sensório-Motor/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores/fisiologia , Esportes , Fatores de Tempo , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-31632836

RESUMO

Background: Embouchure dystonia (ED) is a task-specific dystonia affecting musicians thought to be related to alteration in sensorimotor processing and loss of cortical inhibition. Case Report: Magnetoencephalography-coherence source imaging (MEG-CSI) was used to map connectivity between brain regions by imaging neuronal oscillations that are coherent across the brain in patient with ED at rest and while using the index finger to evoke dystonia normally triggered by playing the flute. Discussion: During rest, there was increased coherence in the bilateral frontal and parietal regions that became more focal during dystonia. Diffuse hyperexcitability and increased coherence persisted in bilateral parietal regions as well as the bilateral frontal regions.


Assuntos
Distúrbios Distônicos/fisiopatologia , Música , Rede Nervosa/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Adulto , Feminino , Humanos , Magnetoencefalografia
15.
Sci Rep ; 9(1): 14165, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578420

RESUMO

For people suffering from severe paralysis, communication can be difficult or nearly impossible. Technology systems called brain-computer interfaces (BCIs) are being developed to assist these people with communication by using their brain activity to control a computer without any muscle activity. To benefit the development of BCIs that employ neural activity related to speech, we investigated if neural activity patterns related to different articulator movements can be distinguished from each other. We recorded with electrocorticography (ECoG), the neural activity related to different articulator movements in 4 epilepsy patients and classified which articulator participants moved based on the sensorimotor cortex activity patterns. The same was done for different movement directions of a single articulator, the tongue. In both experiments highly accurate classification was obtained, on average 92% for different articulators and 85% for different tongue directions. Furthermore, the data show that only a small part of the sensorimotor cortex is needed for classification (ca. 1 cm2). We show that recordings from small parts of the sensorimotor cortex contain information about different articulator movements which might be used for BCI control. Our results are of interest for BCI systems that aim to decode neural activity related to (actual or attempted) movements from a contained cortical area.


Assuntos
Transtornos da Articulação/fisiopatologia , Interfaces Cérebro-Computador , Movimento , Córtex Sensório-Motor/fisiopatologia , Língua/fisiopatologia , Adulto , Transtornos da Articulação/complicações , Eletrocorticografia , Epilepsia/complicações , Feminino , Humanos , Masculino , Língua/inervação , Voz
16.
J Healthc Eng ; 2019: 3817124, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31559004

RESUMO

In the last decade, technology-assisted stroke rehabilitation has been the focus of research. Electroencephalogram- (EEG-) based brain-computer interface (BCI) has a great potential for motor rehabilitation in stroke patients since the closed loop between motor intention and the actual movement established by BCI can stimulate the neural pathways of motor control. Due to the deficits in the brain, motor intention expression may shift to other brain regions during and even after neural reorganization. The objective of this paper was to study the event-related desynchronization (ERD) topography during motor attempt tasks of the paretic hand in stroke patients and compare the classification performance using different channel-selection strategies in EEG-based BCI. Fifteen stroke patients were recruited in this study. A cue-based experimental paradigm was applied in the experiment, in which each patient was required to open the palm of the paretic or the unaffected hand. EEG was recorded and analyzed to measure the motor intention and indicate the activated brain regions. Support vector machine (SVM) combined with common spatial pattern (CSP) algorithm was used to calculate the offline classification accuracy between the motor attempt of the paretic hand and the resting state applying different channel-selection strategies. Results showed individualized ERD topography during the motor attempt of the paretic hand due to the deficits caused by stroke. Statistical analysis showed a significant increase in the classification accuracy by analyzing the channels showing ERD than analyzing the channels from the contralateral sensorimotor cortex (SM1). The results indicated that for stroke patients whose affected motor cortex is extensively damaged, the compensated brain regions should be considered for implementing EEG-based BCI for motor rehabilitation as the closed loop between the altered activated brain regions and the paretic hand can be stimulated more accurately using the individualized channel-selection strategy.


Assuntos
Interfaces Cérebro-Computador , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor , Destreza Motora , Movimento , Reprodutibilidade dos Testes , Córtex Sensório-Motor/fisiopatologia , Máquina de Vetores de Suporte , Tomografia Computadorizada por Raios X
18.
Neuroradiology ; 61(10): 1181-1190, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31399852

RESUMO

PURPOSE: To investigate proliferative reorganization in the bilateral corticospinal tract (CST) and functional reorganization in the sensorimotor network (SMN) after internal capsule stroke, and to examine the significance of this reorganization. METHODS: We recruited 17 patients with first-onset acute stroke (16 male, 1 female, mean age 52 ± 10 years) and 17 age- and sex-matched healthy controls. We excluded patients aged < 18 or > 65 years and those with lesions outside the unilateral internal capsule. All subjects underwent diffusion tensor imaging and resting-state functional MRI on days 7, 30, and 90 from symptom onset. We measured fractional anisotropy (FA) in the CST, interhemispheric functional connectivity (FC) within the SMN, and pre-MRI clinical scores, including the National Institutes of Health Stroke Scale (NIHSS), Barthel Index (BI), and Fugl-Meyer (FM). Correlations among the changes in FA, FC, and clinical scores were analyzed. RESULTS: From day 7 to 90 after stroke, FA in the bilateral CST increased (ipsilesional side, Pinternal capsule = 0.009, Pcentrum semiovale = 0.001; contralesional side, Pinternal capsule = 0.006, Pcentrum semiovale = 0.017), as did FC (P < 0.05); NIHSS scores decreased (P < 0.05), while FM and BI progressively increased (P < 0.05). Increased FA in bilateral CST was negatively correlated with decreased NIHSS scores. Increased FA in only the ipsilesional side was positively correlated with increased FM. Increased FC was positively correlated only with increased BI. CONCLUSION: Proliferative reorganization in the CST and functional reorganization in the SMN support and promote neurological functional recovery after internal capsule infarction.


Assuntos
Infarto Encefálico/diagnóstico , Cápsula Interna/irrigação sanguínea , Imagem por Ressonância Magnética , Regeneração Nervosa/fisiologia , Exame Neurológico , Córtex Sensório-Motor/diagnóstico por imagem , Adulto , Idoso , Infarto Encefálico/fisiopatologia , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Recuperação de Função Fisiológica , Córtex Sensório-Motor/fisiopatologia
19.
Neuroimage Clin ; 24: 101964, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31412309

RESUMO

Pain perception is associated with priming of the motor system and the orienting of attention in healthy adults. These processes correspond with decreases in alpha and beta power in the sensorimotor and parietal cortices. The goal of the present study was to determine whether these findings extend to individuals with chronic pain. Individuals with chronic jaw pain and pain-free controls anticipated and experienced a low pain or a moderate pain-eliciting heat stimulus. Although stimuli were calibrated for each subject, stimulus temperature was not different between groups. High-density EEG data were collected during the anticipation and heat stimulation periods and were analyzed using independent component analyses, EEG source localization, and measure projection analyses. Direct directed transfer function was also estimated to identify frequency specific effective connectivity between regions. Between group differences were most evident during the heat stimulation period. We report three novel findings. First, the chronic jaw pain group had a relative increase in alpha and beta power and a relative decrease in theta and gamma power in sensorimotor cortex. Second, the chronic jaw pain group had a relative increase in power in the alpha and beta bands in parietal cortex. Third, the chronic jaw pain group had less connectivity strength in the beta and gamma bands between sensorimotor cortex and parietal cortex. Our findings show that the effect of chronic pain attenuates rather than magnifies neural responses to heat stimuli. We interpret these findings in the context of system-level changes in intrinsic sensorimotor and attentional circuits in chronic pain.


Assuntos
Dor Crônica/fisiopatologia , Lobo Parietal/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Transtornos da Articulação Temporomandibular/fisiopatologia , Adulto , Eletroencefalografia , Feminino , Humanos , Arcada Osseodentária , Masculino , Percepção da Dor/fisiologia
20.
IEEE Int Conf Rehabil Robot ; 2019: 660-664, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31374706

RESUMO

Proprioceptive deficits are common among stroke survivors and are associated with slower motor recovery, poorer upper limb motor function, and decreased self-care ability. Somatosensory feedback augmenting proprioception should enhance motor control after stroke, but available evidence is inconclusive. This study evaluated the effects of a robot-aided, somatosensory-focused training on proprioceptive acuity and motor performance in individuals with sub-acute and chronic stroke. Twelve stroke survivors completed two training sessions on two consecutive days. During training, participants used a haptic robotic wrist exoskeleton and made continuous, goal-directed wrist ab/adduction movements to a visual target while receiving vibro-tactile feedback. Proprioceptive acuity and active movement errors were assessed before, immediately after, and two days after intervention. Results showed significantly improved proprioceptive acuity at posttest and retention. Motor accuracy measures showed improvements, however these were not statistically significant. This study demonstrates the feasibility of robot-aided somatosensory rehabilitation training in stroke survivors.


Assuntos
Atividade Motora/fisiologia , Propriocepção/fisiologia , Robótica , Córtex Sensório-Motor/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Sobreviventes , Adulto , Idoso , Exoesqueleto Energizado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Punho/fisiopatologia
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