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1.
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
2.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 31(4): 158-164, jul.-ago. 2020. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-193896

RESUMO

INTRODUCCIÓN: Los tumores neuroepiteliales disembrioplásicos (DNET) son un tipo de neoplasia glioneuronal benigna de localización típicamente temporal que producen crisis epilépticas resistentes al tratamiento farmacológico en niños y adultos jóvenes. OBJETIVO: Se muestran 4 casos valorando la utilidad de la resonancia magnética funcional en el estudio prequirúrgico de pacientes con tumores neuroepiteliales disembrionarios. Para la obtención de imágenes se utilizó un equipo de resonancia magnética Philipps Intera de 3.0 Tesla y la técnica Blood Oxygenation Level-Dependent, permitiendo localizar las áreas elocuentes de lenguaje y motora mediante la aplicación de paradigmas específicos. RESULTADOS: En un caso el tumor se encontraba adyacente al área de Broca, en 2 casos coincidía con Wernicke, en un paciente estaba menos de 1cm del área motora de la mano y en otro próximo a la memoria. Solo 2 de los pacientes fueron operados, no produciéndose déficit funcional postoperatorio. Se observó activación hemisférica contralateral al tumor sugestivo de neuroplasticidad en uno de los pacientes. CONCLUSIONES: La resonancia magnética funcional supone un método no invasivo que permite evaluar la proximidad de las lesiones a las áreas elocuentes, clave en la evaluación del riesgo quirúrgico. Además, ha permitido detectar probable neuroplasticidad en un caso, la cual ha garantizado el éxito de la cirugía


INTRODUCTION: Dysembryoplastic neuroepithelial tumours (DNET) are a type of benign glioneuronal neoplasia of typically temporal location that produce drug-resistant epileptic seizures in children and young adults. OBJECTIVE: This work aims to assess the usefulness of functional magnetic resonance imaging (fMRI) in the preoperative study in four patients with DNET. A Philips Intera 3.0 Tesla magnetic resonance imaging scanner and the Blood-Oxygen-Level-Dependent (BOLD) technique were used to obtain the images, making it possible to locate the eloquent areas for language and motor areas through the application of specific paradigms. RESULTS: In one case the tumour was adjacent to Broca's area, in two cases it coincided with Wernicke's area, in one patient it was < 1cm from the motor area for the hand and in another close to memory. Only two of the patients were operated on, without postoperative functional deficit. Hemispheric activation contralateral to the tumour suggestive of neuroplasticity was observed in one of the patients. CONCLUSIONS: fMRI is a non-invasive method that allows us to assess the proximity of lesions to eloquent areas, which is key in the evaluation of surgical risk. In addition, it allowed the detection of probable neuroplasticity in one case, which guaranteed the success of the surgery


Assuntos
Humanos , Neoplasias Neuroepiteliomatosas/diagnóstico por imagem , Neoplasias Neuroepiteliomatosas/fisiopatologia , Encefalopatias/patologia , Lateralidade Funcional/fisiologia , Neuroimagem Funcional/métodos , Imagem por Ressonância Magnética/instrumentação , Área de Wernicke/diagnóstico por imagem , Encefalopatias/fisiopatologia
5.
PLoS One ; 15(7): e0236423, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735611

RESUMO

BACKGROUND: Use of functional MRI (fMRI) in pre-surgical planning is a non-invasive method for pre-operative functional mapping for patients with brain tumors, especially tumors located near eloquent cortex. Currently, this practice predominantly involves task-based fMRI (T-fMRI). Resting state fMRI (RS-fMRI) offers an alternative with several methodological advantages. Here, we compare group-level analyses of RS-fMRI vs. T-fMRI as methods for language localization. PURPOSE: To contrast RS-fMRI vs. T-fMRI as techniques for localization of language function. METHODS: We analyzed data obtained in 35 patients who had both T-fMRI and RS-fMRI scans during the course of pre-surgical evaluation. The RS-fMRI data were analyzed using a previously trained resting-state network classifier. The T-fMRI data were analyzed using conventional techniques. Group-level results obtained by both methods were evaluated in terms of two outcome measures: (1) inter-subject variability of response magnitude and (2) sensitivity/specificity analysis of response topography, taking as ground truth previously reported maps of the language system based on intraoperative cortical mapping as well as meta-analytic maps of language task fMRI responses. RESULTS: Both fMRI methods localized major components of the language system (areas of Broca and Wernicke) although not with equal inter-subject consistency. Word-stem completion T-fMRI strongly activated Broca's area but also several task-general areas not specific to language. RS-fMRI provided a more specific representation of the language system. CONCLUSION: We demonstrate several advantages of classifier-based mapping of language representation in the brain. Language T-fMRI activated task-general (i.e., not language-specific) functional systems in addition to areas of Broca and Wernicke. In contrast, classifier-based analysis of RS-fMRI data generated maps confined to language-specific regions of the brain.


Assuntos
Encéfalo/diagnóstico por imagem , Área de Broca/patologia , Glioblastoma/diagnóstico , Imagem por Ressonância Magnética , Adulto , Idoso , Atenção/fisiologia , Mapeamento Encefálico/métodos , Área de Broca/diagnóstico por imagem , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Lateralidade Funcional/fisiologia , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Descanso/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia , Adulto Jovem
6.
PLoS One ; 15(7): e0235311, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628734

RESUMO

OBJECTIVE: This study aimed to define the prevalence and predictors of non-right-handedness and its link to long-term neurodevelopmental outcome and early neuroimaging in a cohort of children born extremely preterm (<28 weeks gestation). METHODS: 179 children born extremely preterm admitted to the Neonatal Intensive Care Unit of our tertiary centre from 2006-2013 were included in a prospective longitudinal cohort study. Collected data included perinatal data, demographic characteristics, neurodevelopmental outcome measured by the Bayley Scales of Infant and Toddler Development at 2 years and the Movement Assessment Battery for Children at 5 years, and handedness measured at school age (4-8 years). Magnetic resonance imaging performed at term-equivalent age was used to study overt brain injury. Diffusion tensor imaging scans were analysed using tract-based spatial statistics to assess white matter microstructure in relation to handedness and neurodevelopmental outcome. RESULTS: The prevalence of non-right-handedness in our cohort was 22.9%, compared to 12% in the general population. Weaker fine motor skills at 2 years and paternal non-right-handedness were significantly associated with non-right-handedness. Both overt brain injury and fractional anisotropy of white matter structures on diffusion tensor images were not related to handedness. Fractional anisotropy measurements showed significant associations with neurodevelopmental outcome. CONCLUSIONS: Our data show that non-right-handedness in children born extremely preterm occurs almost twice as frequently as in the general population. In the studied population, non-right-handedness is associated with weaker fine motor skills and paternal non-right-handedness, but not with overt brain injury or microstructural brain development on early magnetic resonance imaging.


Assuntos
Encéfalo/crescimento & desenvolvimento , Desenvolvimento Infantil/fisiologia , Imagem de Tensor de Difusão/estatística & dados numéricos , Lateralidade Funcional/fisiologia , Lactente Extremamente Prematuro/crescimento & desenvolvimento , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Criança , Pré-Escolar , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/epidemiologia , Feminino , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Estudos Prospectivos
7.
Neuron ; 107(5): 909-923.e6, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32649865

RESUMO

The parabrachial nucleus (PBN) is one of the major targets of spinal projection neurons and plays important roles in pain. However, the architecture of the spinoparabrachial pathway underlying its functional role in nociceptive information processing remains elusive. Here, we report that the PBN directly relays nociceptive signals from the spinal cord to the intralaminar thalamic nuclei (ILN). We demonstrate that the spinal cord connects with the PBN in a bilateral manner and that the ipsilateral spinoparabrachial pathway is critical for nocifensive behavior. We identify Tacr1-expressing neurons as the major neuronal subtype in the PBN that receives direct spinal input and show that these neurons are critical for processing nociceptive information. Furthermore, PBN neurons receiving spinal input form functional monosynaptic excitatory connections with neurons in the ILN, but not the amygdala. Together, our results delineate the neural circuit underlying nocifensive behavior, providing crucial insight into the circuit mechanism underlying nociceptive information processing.


Assuntos
Vias Aferentes , Lateralidade Funcional/fisiologia , Núcleos Intralaminares do Tálamo , Nociceptividade/fisiologia , Núcleos Parabraquiais , Vias Aferentes/citologia , Vias Aferentes/fisiologia , Tonsila do Cerebelo , Animais , Núcleos Intralaminares do Tálamo/citologia , Núcleos Intralaminares do Tálamo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/citologia , Neurônios/fisiologia , Núcleos Parabraquiais/citologia , Núcleos Parabraquiais/fisiologia , Medula Espinal/citologia , Medula Espinal/fisiologia
8.
J Rehabil Med ; 52(6): jrm00072, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32488286

RESUMO

OBJECTIVE: To examine the clinical and functional characteristics associated with contralateral spatial neglect in right compared with left subacute stroke, and to investigate the correlations between neglect severity and stroke severity, functional ability and outcome. METHODS: Cross-sectional study comparing neurological impairment and disability. The same data-set was used in part 2 of this study. RESULTS: Contralateral neglect was present in 79.7% of right stroke and 68.3% of left stroke rehabilitants, and was, on average, equally mild. Left stroke rehabilitants with neglect had higher stroke severity, cognitive and total disability and dependence level and more impaired sphincter control than right stroke rehabilitants with neglect, while the occurrence of depression, motor and sensory impairment was similar. Rehabilitants with neglect, irrespective of stroke side, had higher stroke severity, cognitive, motor and total disability and dependence level than rehabilitants without neglect. CONCLUSION: In left and right stroke rehabilitants with equally mild neglect, those with left stroke had higher stroke severity, cognitive and total disability and dependence level. Neglect severity correlated with right or left stroke severity and functional ability, moderate to severe neglect correlated significantly more with functioning. Neglect severity was independently associated with functional outcome in right stroke.


Assuntos
Lateralidade Funcional/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/complicações , Transtornos da Percepção/fisiopatologia , Resultado do Tratamento
9.
PLoS One ; 15(6): e0234382, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584824

RESUMO

A brief session of rightward prismatic adaptation (R-PA) has been shown to alleviate neglect symptoms in patients with right hemispheric damage, very likely by switching hemispheric dominance of the ventral attentional network (VAN) from the right to the left and by changing task-related activity within the dorsal attentional network (DAN). We have investigated this very rapid change in functional organisation with a network approach by comparing resting-state connectivity before and after a brief exposure i) to R-PA (14 normal subjects; experimental condition) or ii) to plain glasses (12 normal subjects; control condition). A whole brain analysis (comprising 129 regions of interest) highlighted R-PA-induced changes within a bilateral, fronto-temporal network, which consisted of 13 nodes and 11 edges; all edges involved one of 4 frontal nodes, which were part of VAN. The analysis of network characteristics within VAN and DAN revealed a R-PA-induced decrease in connectivity strength between nodes and a decrease in local efficiency within VAN but not within DAN. These results indicate that the resting-state connectivity configuration of VAN is modulated by R-PA, possibly by decreasing its modularity.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Rede Nervosa/fisiologia , Adaptação Fisiológica , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/terapia , Estudos de Casos e Controles , Conectoma , Óculos , Feminino , Lateralidade Funcional/fisiologia , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Dispositivos Ópticos , Transtornos da Percepção/diagnóstico por imagem , Transtornos da Percepção/fisiopatologia , Transtornos da Percepção/terapia , Adulto Jovem
10.
PLoS One ; 15(6): e0233843, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497147

RESUMO

The vestibular system is essential to produce adequate postural responses enabling voluntary movement. However, how the vestibular system influences corticospinal output during postural tasks is still unknown. Here, we examined the modulation exerted by the vestibular system on corticospinal output during standing. Healthy subjects (n = 25) maintained quiet standing, head facing forward with eyes closed. Galvanic vestibular stimulation (GVS) was applied bipolarly and binaurally at different delays prior to transcranial magnetic stimulation (TMS) which triggered motor evoked potentials (MEPs). With the cathode right/anode left configuration, MEPs in right Soleus (SOL) muscle were significantly suppressed when GVS was applied at ISI = 40 and 130ms before TMS. With the anode right/cathode left configuration, no significant changes were observed. Changes in the MEP amplitude were then compared to changes in the ongoing EMG when GVS was applied alone. Only the decrease in MEP amplitude at ISI = 40ms occurred without change in the ongoing EMG, suggesting that modulation occurred at a premotoneuronal level. We further investigated whether vestibular modulation could occur at the motor cortex level by assessing changes in the direct corticospinal pathways using the short-latency facilitation of the SOL Hoffmann reflex (H-reflex) by TMS. None of the observed modulation occurred at the level of motor cortex. Finally, using the long-latency facilitation of the SOL H-reflex, we were able to confirm that the suppression of MEP at ISI = 40ms occurred at a premotoneuronal level. The data indicate that vestibular signals modulate corticospinal output to SOL at both premotoneuronal and motoneuronal levels during standing.


Assuntos
Eletromiografia/métodos , Tratos Piramidais/fisiologia , Posição Ortostática , Vestíbulo do Labirinto/fisiologia , Adulto , Potencial Evocado Motor/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Reflexo H/fisiologia , Voluntários Saudáveis , Humanos , Masculino , Córtex Motor/fisiologia , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Estimulação Transcraniana por Corrente Contínua , Estimulação Magnética Transcraniana , Adulto Jovem
11.
Nat Commun ; 11(1): 2839, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503986

RESUMO

Proper speech production requires auditory speech feedback control. Models of speech production associate this function with the right cerebral hemisphere while the left hemisphere is proposed to host speech motor programs. However, previous studies have investigated only spectral perturbations of the auditory speech feedback. Since auditory perception is known to be lateralized, with right-lateralized analysis of spectral features and left-lateralized processing of temporal features, it is unclear whether the observed right-lateralization of auditory speech feedback processing reflects a preference for speech feedback control or for spectral processing in general. Here we use a behavioral speech adaptation experiment with dichotically presented altered auditory feedback and an analogous fMRI experiment with binaurally presented altered feedback to confirm a right hemisphere preference for spectral feedback control and to reveal a left hemisphere preference for temporal feedback control during speaking. These results indicate that auditory feedback control involves both hemispheres with differential contributions along the spectro-temporal axis.


Assuntos
Cérebro/fisiologia , Retroalimentação Sensorial/fisiologia , Lateralidade Funcional/fisiologia , Percepção da Fala/fisiologia , Fala/fisiologia , Estimulação Acústica , Adulto , Mapeamento Encefálico , Feminino , Voluntários Saudáveis , Humanos , Aprendizagem , Imagem por Ressonância Magnética , Masculino , Fatores de Tempo
12.
Stroke ; 51(7): 2208-2218, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32521221

RESUMO

BACKGROUND AND PURPOSE: The therapeutic use of transcranial direct current stimulation (tDCS), an adjuvant tool for stroke, induces long-term changes in cortical excitability, for example, the secretion of activity-dependent growth factors. We assessed the proper therapeutic configuration of high-definition tDCS (HD-tDCS) in the subacute stage of ischemic stroke and its underlying expression profiling of growth factors to propose a new method for ensuring better therapeutic effects. METHODS: Male C57BL/6J mice were subjected to middle cerebral artery occlusion, after which repetitive HD-tDCS (20 minutes, 55 µA/mm2, charge density 66 000 C/m2) was applied from subacute phases of their ischemic insult. Behavioral tests assessing motor and cognitive functions were used to determine suitable conditions and HD-tDCS stimulation sites. Gene expression profiling of growth factors and their secretion and activation were analyzed to shed light on the underlying mechanisms. RESULTS: Anodal HD-tDCS application over the contralesional cortex, especially the motor cortex, was more effective than ipsilesional stimulation in attenuating motor and cognitive deficits. In the HD-tDCS application over the contralesional motor cortex, positive changes in Bmp8b, Gdf5, Il4, Pdgfa, Pgf, and Vegfb were observed in the ipsilesional site. The expression of GDF5 (growth/differentiation factor 5) and PDGFA (platelet-derived growth factor subunit A) tended to similarly increase in both ipsi- and contralesional striata. However, higher expression levels of GDF5 and PDGFA and their receptors were observed in the peri-infarct regions of the striatum after HD-tDCS, especially in PDGFA expression. A higher number of proliferating or newly formed neuronal cells was detected in ipsilesional sites such as the subventricular zone. CONCLUSIONS: Application of anodal HD-tDCS over the contralesional cortex may enhance beneficial recovery through the expression of growth factors, such as GDF5 and PDGFA, in the ipsilesional site. Therefore, this therapeutic configuration may be applied in the subacute stage of ischemic stroke to ameliorate neurological impairments.


Assuntos
Lateralidade Funcional/fisiologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Estimulação Transcraniana por Corrente Contínua , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Fator 5 de Diferenciação de Crescimento/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Derivado de Plaquetas/biossíntese , Acidente Vascular Cerebral/metabolismo
13.
J Neuroeng Rehabil ; 17(1): 64, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410626

RESUMO

PURPOSE: The purpose of this study was to investigate transient bimanual effects on the force control capabilities of the paretic and non-paretic arms in individuals post stroke across submaximal and maximal force control tasks. METHODS: Fourteen chronic stroke patients (mean age = 63.8 ± 15.9; stroke duration = 38.7 ± 45.2 months) completed two isometric force control tasks: (a) submaximal control and (b) maximal sustained force production. Participants executed both tasks with their wrist and fingers extending across unimanual (paretic and non-paretic arms) and bimanual conditions. Mean force, force variability using coefficient of variation, force regularity using sample entropy were calculated for each condition. RESULTS: During the submaximal force control tasks (i.e., 5, 25, and 50% of maximum voluntary contraction), the asymmetrical mean force between the paretic and non-paretic arms decreased from unimanual to bimanual conditions. The asymmetry of force variability and regularity between the two arms while executing unimanual force control tended to decrease in the bimanual condition because of greater increases in the force variability and regularity for the non-paretic arm than those for the paretic arm. During the maximal sustained force production tasks (i.e., 100% of maximum voluntary contraction), the paretic arm increased maximal forces and decreased force variability in the bimanual condition, whereas the non-paretic arm reduced maximal forces and elevated force variability from unimanual to bimanual conditions. CONCLUSIONS: The current findings support a proposition that repetitive bimanual isometric training with higher execution intensity may facilitate progress toward stroke motor recovery.


Assuntos
Paresia/reabilitação , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/complicações , Idoso , Feminino , Lateralidade Funcional/fisiologia , Humanos , Contração Isométrica/fisiologia , Masculino , Pessoa de Meia-Idade , Paresia/etiologia , Paresia/fisiopatologia , Extremidade Superior/fisiopatologia
14.
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
15.
Eur J Paediatr Neurol ; 27: 49-59, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32417186

RESUMO

Cerebral Palsy (CP) is a complex neurological disorder, characterized by congenital motor disability associated with behaviour, perception and cognition disorders. The sensorimotor impairments represent the main hallmark of the disease, significantly impacting the quality of life. So far, few studies have investigated motor learning abilities in CP and their association with the plastic reorganization of the motor system remains largely unknown. The present proof-of-principle study explored explicit motor sequence learning in children with unilateral CP and different patterns of motor system reorganization (bilateral, ipsilateral, contralateral). Children with unilateral CP, and a group of age-matched typically developing (TD) children, underwent a sequential finger tapping task, performed with the affected hand by children with CP and with the non-dominant hand by TD children. The pattern of corticospinal tract projections in hemiparetic patients was assessed by single-pulse Transcranial Magnetic Stimulation (TMS). Results showed the presence of finger dexterity impairments in children with unilateral CP presenting with a bilateral or an ipsilateral control of the affected (trained) hand, as compared to TD children. Conversely, motor sequence learning was impaired in unilateral CP with ipsilateral or contralateral corticospinal reorganization, but not in the case of a bilateral control of the paretic hand. These preliminary findings, although referred to small clinical samples, suggest that unilateral control of the paretic upper-limb, from the ipsilateral or the contralateral motor cortex, may not be sufficient to develop typical motor learning with the affected hand, which seems to require a bilateral representation in the motor cortex. This evidence has potential implications for fine motor skills rehabilitation in CP.


Assuntos
Paralisia Cerebral/fisiopatologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Tratos Piramidais/fisiopatologia , Adolescente , Paralisia Cerebral/complicações , Criança , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Plasticidade Neuronal/fisiologia , Projetos Piloto , Estimulação Magnética Transcraniana
16.
PLoS One ; 15(4): e0232123, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324801

RESUMO

The purpose of the present study was to: (a) assess centripetal force (CentF) and changes of direction (COD) in elite soccer players according to playing position (central defender, CD; lateral defender, LD; central midfielder, CM; lateral midfielder, LM; forward, FW), laterality (right-footed vs. left-footed) and field zone (central vs. lateral), and (b) analyze the relationship between anthropometric characteristics (age, weight, height, body mass and fat mass) and non-linear locomotion workload. Thirty professional soccer players (age: 26.57±5.56 years) were tracked during the 2017-2018 season during friendly, national and international matches (38 total games) using inertial measurement devices. CentF and COD were the variables extracted for analysis. A one-way ANOVA was used for playing position comparison, a t-test for laterality and field zone, and Pearson's correlation coefficient to analyze relationships between anthropometric characteristics and dependent variables. There were differences by playing position in COD (556.33-to-412.18), R20COD (484.36-to-354.81) and R60COD (48.38-to-38.61) (p < .01; ωp2 = 0.03-to-0.05; CD>CM>LD>LM = FW); in CODHIA (49.75-to-37.11), R20CODHIA (16.04-to-9.11) and R60CODHIA (10.64-to-9.11) (p < .01; ωp2 = 0.03-to-0.07; CM>FW>LM>CD = LD); in CODSPRINT (14.56-to-8.40) and R20CODSPRINT (3.29-to-1.40) (p < .01; ωp2 = 0.03-to-0.04; FW = LM = CM>CD = LD); and in CentFMAX both in clockwise (992.04-to-902.09N) and counterclockwise (999.24-to-872.61N) directions (p < .02; ωp2 = 0.02-to-0.07; FW = CD>CM = LM = LD). The highest values of counterclockwise CentF were performed by left-footed players in the central zone (p < .001; d = 0.71-to-1.44) and clockwise CentF by right-footed players (p < .001; d = 0.04-to-0.55) in the lateral field zone. Moderate correlations were found between age, body mass and high intensity/sprints COD and repeated COD ability (p < .05; r = 0.235-to-0.383). Therefore, team staff should consider anthropometric characteristics, playing position, laterality and field zone to individualize training workload related to non-linear locomotion in soccer.


Assuntos
Desempenho Atlético/fisiologia , Lateralidade Funcional/fisiologia , Futebol/fisiologia , Acelerometria , Adulto , Antropometria , Europa (Continente) , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
17.
Physiol Rev ; 100(3): 1019-1063, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32233912

RESUMO

Comparative studies on brain asymmetry date back to the 19th century but then largely disappeared due to the assumption that lateralization is uniquely human. Since the reemergence of this field in the 1970s, we learned that left-right differences of brain and behavior exist throughout the animal kingdom and pay off in terms of sensory, cognitive, and motor efficiency. Ontogenetically, lateralization starts in many species with asymmetrical expression patterns of genes within the Nodal cascade that set up the scene for later complex interactions of genetic, environmental, and epigenetic factors. These take effect during different time points of ontogeny and create asymmetries of neural networks in diverse species. As a result, depending on task demands, left- or right-hemispheric loops of feedforward or feedback projections are then activated and can temporarily dominate a neural process. In addition, asymmetries of commissural transfer can shape lateralized processes in each hemisphere. It is still unclear if interhemispheric interactions depend on an inhibition/excitation dichotomy or instead adjust the contralateral temporal neural structure to delay the other hemisphere or synchronize with it during joint action. As outlined in our review, novel animal models and approaches could be established in the last decades, and they already produced a substantial increase of knowledge. Since there is practically no realm of human perception, cognition, emotion, or action that is not affected by our lateralized neural organization, insights from these comparative studies are crucial to understand the functions and pathologies of our asymmetric brain.


Assuntos
Evolução Biológica , Encéfalo/fisiologia , Lateralidade Funcional/genética , Lateralidade Funcional/fisiologia , Animais , Encéfalo/anatomia & histologia , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Pesquisa/história
18.
Niger J Clin Pract ; 23(4): 545-549, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32246663

RESUMO

Background: Handedness is one of the individual characteristics that causes different mental and practical capabilities including different abilities to perform oral hygiene instructions. It seems that the right-handed and left-handed individuals have different ability in brushing and removing plaque at different areas of the mouth. Aims: To investigate the effect of handedness on decay pattern, gingival index, and plaque index in 6-10 years old children. Subjects and Methods: In this cross-sectional study, children 6-10 years of age who fulfilled the inclusion criteria were selected. Dental caries and plaque and gingival indices were also measured and recorded for each child. Then the relationship between the handedness and the recorded variables was evaluated. Independent t-test and nonparametric Mann-Whitney test were used for the statistical comparison of quantitative variables between two right-handed and left-handed groups and Chi-square test was used for the statistical comparison of qualitative variables between these two groups. Data were analyzed using SPSS software version 20. Results: The results showed that there was no significant relationship between any of the variables with being left- or right-handed. A significant relationship was observed only between the lowest plaque index and handedness (P < 0.05). Conclusion: A relationship cannot be considered between the handedness of children and their oral health status.


Assuntos
Cárie Dentária/epidemiologia , Lateralidade Funcional/fisiologia , Índice Periodontal , Criança , Estudos Transversais , Humanos
19.
Stroke ; 51(5): 1442-1450, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32299324

RESUMO

Background and Purpose- Low-frequency oscillations reflect brain injury but also contribute to normal behaviors. We examined hypotheses relating electroencephalography measures, including low-frequency oscillations, to injury and motor recovery poststroke. Methods- Patients with stroke completed structural neuroimaging, a resting-state electroencephalography recording and clinical testing. A subset admitted to an inpatient rehabilitation facility also underwent serial electroencephalography recordings. The relationship that electroencephalography measures (power and coherence with leads overlying ipsilesional primary motor cortex [iM1]) had with injury and motor status was assessed, focusing on delta (1-3 Hz) and high-beta (20-30 Hz) bands. Results- Across all patients (n=62), larger infarct volume was related to higher delta band power in bilateral hemispheres and to higher delta band coherence between iM1 and bilateral regions. In chronic stroke, higher delta power bilaterally correlated with better motor status. In subacute stroke, higher delta coherence between iM1 and bilateral areas correlated with poorer motor status. These coherence findings were confirmed in serial recordings from 18 patients in an inpatient rehabilitation facility. Here, interhemispheric coherence between leads overlying iM1 and contralesional M1 was elevated at inpatient rehabilitation facility admission compared with healthy controls (n=22), declining to control levels over time. Decreases in interhemispheric coherence between iM1 and contralesional M1 correlated with better motor recovery. Conclusions- Delta band coherence with iM1 related to greater injury and poorer motor status subacutely, while delta band power related to greater injury and better motor status chronically. Low-frequency oscillations reflect both injury and recovery after stroke and may be useful biomarkers in stroke recovery and rehabilitation.


Assuntos
Modalidades de Fisioterapia , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/cirurgia , Adulto , Idoso , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Plasticidade Neuronal/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Reabilitação do Acidente Vascular Cerebral/métodos , Estimulação Magnética Transcraniana/métodos
20.
Clin J Sport Med ; 30(3): 279-281, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32341293

RESUMO

OBJECTIVE: To identify relationships between self-reported limb preferences and performance measures for determining limb dominance in adolescent female basketball players. DESIGN: Cross-sectional cohort study. PARTICIPANTS: Forty adolescent female basketball players. INDEPENDENT VARIABLES AND MAIN OUTCOME MEASURES: Participants provided self-reported preferred kicking and jumping limbs, then completed 3 trials of a single-limb countermovement hop (HOPVER) and unilateral triple hop for distance (HOPHOR) on each limb. Each test was used to independently define limb dominance by the limb that produced the largest maximum vertical height and horizontal distance, respectively. RESULTS: Chi-square tests for independence identified a significant relationship between self-reported preferred kicking and jumping legs (χ = 7.41, P = 0.006). However, no significant relationships were found when comparing self-reported preference to measures of performance during the HOPHOR (χ = 0.33, P = 0.57) or HOPVER (χ = 0.06, P = 0.80). In addition, the 2 performance measures did not consistently produce the same definition of limb dominance among individuals (χ = 1.52, P = 0.22). CONCLUSIONS: Self-selection of the dominant limb is unrelated to performance. Furthermore, limb dominance, as defined by vertical jump height, is unrelated to limb dominance defined by horizontal jump distance. The results of this study call into question the validity of consistently defining limb dominance by self-reported measures in adolescent female basketball players.


Assuntos
Basquetebol/fisiologia , Lateralidade Funcional/fisiologia , Extremidade Inferior/fisiologia , Adolescente , Fenômenos Biomecânicos , Estudos Transversais , Teste de Esforço , Feminino , Humanos , Autorrelato
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