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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 851-854, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018118

RESUMO

Air Traffic Control (ATC) has been classified as the fourth most stressful job. In this regard, sixteen controllers were asked to perform ecological ATC simulation during which behavioral (Radio Communications with pilots - RCs), subjective (stress perception) and neurophysiological signals (brain activity and skin conductance - SC) were collected. All the considered parameters reported significant changes under high stress conditions. In particular, the theta, alpha, and beta brain rhythms increased significantly (all p<0.05) all over the brain areas, and both the SC components exhibited higher values (p<0.01). Additionally, the number of speech under high stress decreased significantly (p<10-4) while both the mean and median value of the F0 component of the RC increased (p<0.01). The results can be employed to objectively measure and track the controller's stress level while dealing with ATC activities to better tailoring the workshift and maintaining high safety levels.


Assuntos
Aviação , Neurofisiologia , Ritmo beta , Encéfalo , Humanos , Fala
2.
Neurol Neurochir Pol ; 54(5): 466-470, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32939748

RESUMO

Peripheral neuropathy is a disorder of the peripheral nerves and results from a disturbance of structure and/or function of the peripheral sensory, motor and/or autonomic neurons. The possible aetiology of peripheral neuropathies is diverse, but inflammatory and hereditary diseases of the peripheral nerves predominate in childhood. The aim of this study was to determine the clinical and electrophysiological profile of large nerve fibre neuropathy detected by nerve conduction studies (NCS) in children over a 10-year period at the Children's Clinical University Hospital in Latvia. Based on NCS findings, 165 children between 2008 and 2018 were diagnosed with polyneuropathy. In our study, the majority of children had peripheral neuropathy due to acquired causes, mostly due to diabetes mellitus; roughly one in five of the patients had hereditary neuropathy. Almost half of the patients had motor deficits, which were more prevalent in toxic and inflammatory neuropathies. A little less than a third of patients complained of pain as well as presenting with autonomic dysfunction symptoms. The NCS demonstrated a demyelinating neuropathy in 52 cases (31%), an axonal neuropathy in 34 cases (21%), and mixed polyneuropathy in 79 cases (48%). Our study investigated the clinical and electrophysiological characteristics of polyneuropathies diagnosed with NCS in children. Most of the polyneuropathies in our study were hereditary and diabetic neuropathies with combined (myelin and axon) damage to nerve fibres. Almost all clinical symptoms of polyneuropathy were present in all aetiological groups.


Assuntos
Polineuropatias , Criança , Humanos , Condução Nervosa , Exame Neurológico , Neurofisiologia , Nervos Periféricos , Polineuropatias/epidemiologia , Polineuropatias/genética
4.
Nat Commun ; 11(1): 4057, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792523

RESUMO

Mammalian cortex has both local and cross-area connections, suggesting vital roles for both local and cross-area neural population dynamics in cortically-dependent tasks, like movement learning. Prior studies of movement learning have focused on how single-area population dynamics change during short-term adaptation. It is unclear how cross-area dynamics contribute to movement learning, particularly long-term learning and skill acquisition. Using simultaneous recordings of rodent motor (M1) and premotor (M2) cortex and computational methods, we show how cross-area activity patterns evolve during reach-to-grasp learning in rats. The emergence of reach-related modulation in cross-area activity correlates with skill acquisition, and single-trial modulation in cross-area activity predicts reaction time and reach duration. Local M2 neural activity precedes local M1 activity, supporting top-down hierarchy between the regions. M2 inactivation preferentially affects cross-area dynamics and behavior, with minimal disruption of local M1 dynamics. Together, these results indicate that cross-area population dynamics are necessary for learned motor skills.


Assuntos
Aprendizagem/fisiologia , Córtex Motor/fisiologia , Animais , Eletrofisiologia , Masculino , Neurofisiologia , Dinâmica Populacional , Ratos , Tempo de Reação/fisiologia
5.
Int J Biometeorol ; 64(12): 2007-2017, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32820392

RESUMO

A new neurophysiological human thermal model based on thermoreceptor responses, the NHTM model, has been developed to predict regulatory responses and physiological variables in asymmetric transient environments. The passive system is based on Wissler's model, which is more complex and refined. Wissler's model segments the human body into 21 cylindrical parts. Each part is divided into 21 layers, 15 for the tissues and 6 for clothes, and each layer is divided into 12 angular sectors. Thus, we have 3780 nodes for the tissues and 1512 for clothes. The passive system simulates heat exchange within the body and between the body and the surroundings. The active system is composed of the thermoregulatory mechanisms, i.e., skin blood flow, shivering thermogenesis, and sweating. The skin blood flow model and the shivering model are based on thermoreceptor responses. The sweating model is that of Fiala et al. and is based on error signals. The NHTM model was compared with Wissler's model, and the results showed that a calculation based on neurophysiology can improve the performance of the thermoregulation model. The NHTM model was more accurate in the prediction of mean skin temperature, with a mean absolute error of 0.27 °C versus 0.80 °C for the original Wissler model. The prediction accuracy of the NHTM model for local skin temperatures and core temperature could be improved via an optimization method to prove the ability of the new thermoregulation model to fit with the physiological characteristics of different populations.


Assuntos
Neurofisiologia , Termorreceptores , Regulação da Temperatura Corporal , Humanos , Temperatura Cutânea , Sudorese
7.
Neuron ; 107(4): 600-602, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32758423

RESUMO

To establish a genuine scientific discourse, we must accept a long due departure from the habit of neatly arranging things in a hierarchy where "macroscopic" psychological mystery awaits explanation in terms of "microscopic" neural objects. Instead, a relational scientific methodology is wanted, accompanied by a dialogic mode of conversation between the disciplines.


Assuntos
Comunicação Interdisciplinar , Neurofisiologia , Psicologia , Humanos
8.
Stud Health Technol Inform ; 272: 318-321, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604666

RESUMO

In neurosurgery, intraoperative neurophysiological monitoring (IOM) with continuous measurements of neural electrical activity may reduce the risk of postoperative deficits. During an IOM, surgical information as well as neurophysiological, surgical and anesthesia events have to be recorded. So far, there is no common standard for this task available. In this paper, such a standardization with the aim of facilitating the data input and making the protocols data available for different sorts of analyses is described. We developed a protocol entry catalog with 200 standard expressions, which were divided into four categories: IOM, surgical procedure, anesthesia and others. An empirical assessment of the catalog by the IOM team showed the need for subcategories. In the final version of the catalog, the standard terms were grouped into 25 subcategories. The catalog is a first step to support systematic research into the occurrence of clinical events during the IOM and their association with postoperative neurological deficits that could enable improved surgical procedures in the future.


Assuntos
Anestesia , Neurocirurgia , Monitorização Intraoperatória , Neurofisiologia , Procedimentos Neurocirúrgicos
9.
Neurol Sci ; 41(9): 2345-2351, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32696088

RESUMO

BACKGROUND: During COVID-19 lockdown, non-urgent medical procedures were suspended. Grade of urgency of electroencephalography (EEG) may vary according to the clinical indication, setting, and status of infection of SARS-CoV-2 virus. "Italian Society of Clinical Neurophysiology" (SINC), "Italian League Against Epilepsy" (LICE), and the "Italian Association of Neurophysiology Technologists" (AITN) aimed to provide clinical and technical recommendation for EEG indications and recording standards in this pandemic era. METHODS: Presidents of SINC, LICE, and AITN endorsed three members per each society to formulate recommendations: classification of the degree of urgency of EEG clinical indications, management and behavior of physicians and neurophysiology technologists, hygiene and personal protection standards, and use of technical equipment. RESULTS: Scientific societies endorsed a paper conveying the recommendation for EEG execution in accordance with clinical urgency, setting (inpatients/outpatients), status of SARS-CoV-2 virus infection (positive, negative and uncertain), and phase of governmental restrictions (phase 1 and 2). Briefly, in phase 1, EEG was recommended only for those acute/subacute neurological symptoms where EEG is necessary for diagnosis, prognosis, or therapy. Outpatient examinations should be avoided in phase 1, while they should be recommended in urgent cases in phase 2 when they could prevent an emergency room access. Reduction of staff contacts must be encouraged through rescheduling job shifts. The use of disposable electrodes and dedicated EEG devices for COVID-19-positive patients are recommended. CONCLUSIONS: During the different phases of COVID-19 pandemic, the EEG should be reserved for patients really benefiting from its execution in terms of diagnosis, treatment, prognosis, and avoidance of emergency room access.


Assuntos
Betacoronavirus , Infecções por Coronavirus/fisiopatologia , Eletroencefalografia/normas , Epilepsia/fisiopatologia , Pneumonia Viral/fisiopatologia , Guias de Prática Clínica como Assunto/normas , Sociedades Médicas/normas , Comitês Consultivos/normas , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Surtos de Doenças/prevenção & controle , Epilepsia/diagnóstico , Epilepsia/epidemiologia , Humanos , Itália/epidemiologia , Pessoal de Laboratório Médico/normas , Neurofisiologia/métodos , Neurofisiologia/normas , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia
10.
Neurol Sci ; 41(8): 1999-2004, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32588368

RESUMO

OBJECTIVE: During the Covid-19 pandemic, government restrictions limited health care to urgent needs. Neurophysiology centers had to suddenly reschedule their activities, with a lack of specific recommendations about electroencephalography (EEG) execution. During the pandemic phase 1, we launched an online survey to understand the flaws and strengths of the EEG management in Italy at the time of Covid-19 pandemic. METHODS: A 45-item online survey (published from April 16 to 30, 2020), endorsed by the Italian Society of Clinical Neurophysiology (SINC), the Italian League Against epilepsy (LICE), and the Italian Association of Neurophysiology technologists (AITN), collected EEG management data (EEG's number and type, indications, personnel and patients safety, devices' sanification) during the Covid-19 pandemic. RESULTS: We received responses from 206 centers. The number of EEGs performed was reduced by 76 ± 20%, and several types of specific EEG (video-EEG, ambulatory-EEG, LTM, polysomnography) were reduced at a minimum. Half of the centers performed inpatient EEGs only for urgencies. Repetitive seizures, encephalitis, and non-convulsive status epilepticus were the most common indications. Covid-19-positive patients received less EEG than negative ones (p < 0.0001). EEG requests came mainly not only from neurologists (n = 176) but also from general practitioners (n = 40), emergentists (n = 79), intensivists (n = 72), and other specialists (n = 53). Those centers which continued performing outpatient EEG examinations were instructed to perform the EEG after a Covid-19-related symptom screening for patients and using personal protective equipment (PPE) through all the procedure. Inpatient EEGs were performed using FFP2/FFP3 masks by neurophysiology technologists in only 50% of cases. Patients executed hyperventilation only for real clinical needs, but often (56%) with a mask. CONCLUSIONS: Italian neurophysiology centers strongly adhered to government restrictions of lockdown. Some issues emerged, ranging from the evaluation of a proper indication for EEG, technical procedures of EEG recording, and protection of neurophysiology technicians.


Assuntos
Infecções por Coronavirus , Eletroencefalografia , Neurofisiologia , Pandemias , Pneumonia Viral , Quarentena , Betacoronavirus , Eletroencefalografia/métodos , Eletroencefalografia/normas , Eletroencefalografia/estatística & dados numéricos , Humanos , Itália , Neurofisiologia/métodos , Neurofisiologia/normas , Neurofisiologia/estatística & dados numéricos , Equipamento de Proteção Individual/normas , Inquéritos e Questionários
11.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 47(2): 72-74, abr.-jun. 2020.
Artigo em Espanhol | IBECS | ID: ibc-193714

RESUMO

Los síndromes neurológicos paraneoplásicos son un conjunto de trastornos, raramente asociados a tumores ginecológicos. Su presencia debe alertarnos sobre la posible existencia de un tumor maligno subyacente. Presentamos un caso de miastenia gravis, como manifestación paraneoplásica de un cáncer de ovario primario avanzado


Paraneoplastic neurological syndromes are an unusual diseases rarely associated with gynaecological tumours. Their presence must alert on the possible existence of an underlying malignant tumour. A rare case is presented of myasthenia gravis as a paraneoplastic manifestation of an advanced primary ovarian cancer


Assuntos
Humanos , Feminino , Idoso de 80 Anos ou mais , Miastenia Gravis/etiologia , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/terapia , Polineuropatia Paraneoplásica , Transtornos Neurológicos da Marcha/complicações , Transtornos de Deglutição/complicações , Neurofisiologia , Tomografia por Emissão de Pósitrons , Histeroscopia
12.
Proc Natl Acad Sci U S A ; 117(26): 14667-14675, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32532923

RESUMO

Many natural materials possess built-in structural variation, endowing them with superior performance. However, it is challenging to realize programmable structural variation in self-assembled synthetic materials since self-assembly processes usually generate uniform and ordered structures. Here, we report the formation of asymmetric microribbons composed of directionally self-assembled two-dimensional nanoflakes in a polymeric matrix during three-dimensional direct-ink printing. The printed ribbons with embedded structural variations show site-specific variance in their mechanical properties. Remarkably, the ribbons can spontaneously transform into ultrastretchable springs with controllable helical architecture upon stimulation. Such springs also exhibit superior nanoscale transport behavior as nanofluidic ionic conductors under even ultralarge tensile strains (>1,000%). Furthermore, to show possible real-world uses of such materials, we demonstrate in vivo neural recording and stimulation using such springs in a bullfrog animal model. Thus, such springs can be used as neural electrodes compatible with soft and dynamic biological tissues.


Assuntos
Neuroestimuladores Implantáveis , Microtecnologia/instrumentação , Nanoestruturas , Impressão Tridimensional , Animais , Anuros , Elasticidade , Grafite/química , Íons/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Neurofisiologia/instrumentação , Nervo Isquiático/fisiologia
13.
HNO ; 68(Suppl 2): 69-78, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32533211

RESUMO

BACKGROUND: Vestibular evoked myogenic potentials (VEMPs) are increasingly being used for testing otolith organ function. OBJECTIVE: This article provides an overview of the anatomical, biomechanical and neurophysiological principles underlying the evidence-based clinical application of ocular and cervical VEMPs (oVEMPs and cVEMPs). MATERIAL AND METHODS: Systematic literature search in PubMed until April 2019. RESULTS: Sound and vibration at a frequency of 500 Hz represent selective vestibular stimuli for the otolith organs. The predominant specificity of oVEMPs for contralateral utricular function and of cVEMPs for ipsilateral saccular function is defined by the different central projections of utricular and saccular afferents. VEMPs are particularly useful in the diagnosis of superior canal dehiscence and otolith organ specific vestibular dysfunction and as an alternative diagnostic approach in situations when video oculography is not possible or useful. CONCLUSION: The use of VEMPs is a simple, safe, reliable and selective test of dynamic function of otolith organs.


Assuntos
Doenças Vestibulares , Potenciais Evocados Miogênicos Vestibulares , Medicina Baseada em Evidências , Humanos , Neurofisiologia , Membrana dos Otólitos , Vibração
14.
Artigo em Inglês | MEDLINE | ID: mdl-32517043

RESUMO

The aim of this pilot study was to analyse the influence of Galvanic Skin Response (GSR) Biofeedback training in a group of 18 men with schizophrenia at the remission stage. The results were verified according to: Positive and Negative Syndrome Scale (PANSS), Acceptance of Illness Scale (AIS), Self-efficacy Scale (GSES), Beck Cognitive Insight Scale (BCIS) scales, Colour Trial Test (CTT-1, CTT-2), d2 psychological tests, Quantitative Electroencephalogram (QEEG) Biofeedback, auditory event-related potentials (ERPs), and serum levels of brain-derived neurotrophic factor (BDNF). The results were compared in the same patients after 3 months. Statistically significant changes were noted in results for the variables on the PANSS scale. For the BDNF variable, a statistically significant increase occurred, indicating that GSR Biofeedback training may influence serum levels of the neurotrophic factor. Statistically significant changes were noted in results for the variables on the BCIS, AIS, and GSES indicating an improvement in the cognitive and social functioning. Changes were noted for results for theta/beta and theta/Sensory Motor Rhythm (SMR) ratios, which indicate an improvement in concentration and attention. Changes were noted for the N1 wave amplitude in the frontal brain region (F-z), and for the P2 wave latency in the central brain region (C-z), which indicates an improvement in the initial perceptual analysis. The use of GSR Biofeedback in a group of patients with schizophrenia gives interesting results, but requires further in-depth research.


Assuntos
Neurofisiologia , Esquizofrenia , Fator Neurotrófico Derivado do Encéfalo , Cognição , Lobo Frontal , Humanos , Masculino , Projetos Piloto
17.
J Athl Train ; 55(6): 594-600, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32396473

RESUMO

CONTEXT: Detection of subtle changes in brain sensorimotor processes may enable clinicians to identify athletes who would derive the greatest benefit from interventions designed to reduce the risk for future injury and progressive neurologic or musculoskeletal dysfunction. OBJECTIVE: To develop a generalizable statistical model for identifying athletes who possess subtle alterations in sensorimotor processes that may be due to previous concussion. DESIGN: Cross-sectional study. SETTING: Residential Olympic Training Center sports medicine clinic. PATIENTS OR OTHER PARTICIPANTS: A primary cohort of 35 elite athletes and a secondary cohort of 40 elite athletes who performed identical tests the preceding year. INTERVENTION(S): Two upper extremity tests of visual-motor reaction time and 2 tests of whole-body reactive agility were administered. The whole-body tests required lateral or diagonal responses to virtual-reality targets, which provided measures of reaction time, speed, acceleration, and deceleration. MAIN OUTCOME MEASURE(S): Sport-related concussion history, which was reported by 54% (n = 19) of the athletes in the primary cohort and 45% (n = 18) of the athletes in the secondary cohort. RESULTS: Univariable analyses identified 12 strong predictors of sport-related concussion history, which we combined to create a composite metric with maximum predictive value. Composite lateral asymmetry for whole-body reactive movements and persisting effects of previous musculoskeletal injury yielded a logistic regression model with exceptionally good discrimination (area under the curve = 0.845) and calibration (predicted-observed probabilities within 7 subgroups: r = 0.959, P = .001). Application of the derived model to compatible data acquired from another cohort of elite athletes demonstrated very good discrimination (area under the curve = 0.772) and calibration (within 8 subgroups: r = 0.849, P = .008). CONCLUSIONS: Asymmetry in whole-body reactive movement capabilities may be a manifestation of a subtle abnormality in the functional connectivity of brain networks that might be relevant to previously reported associations between sport-related concussion history and musculoskeletal injury occurrence.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Retroalimentação Sensorial/fisiologia , Lateralidade Funcional , Desempenho Psicomotor , Adulto , Atletas , Traumatismos em Atletas/fisiopatologia , Traumatismos em Atletas/prevenção & controle , Traumatismos em Atletas/psicologia , Concussão Encefálica/fisiopatologia , Concussão Encefálica/prevenção & controle , Estudos Transversais , Feminino , Humanos , Masculino , Modelos Estatísticos , Neurofisiologia/métodos , Tempo de Reação/fisiologia , Medição de Risco , Fatores de Risco
18.
Hautarzt ; 71(7): 487-492, 2020 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-32468292

RESUMO

BACKGROUND: The mutual exchange of results between basic sciences and clinical research as well as their translation into practice, also with regard to chronic pruritus, is currently to be seen as an ambition or hope rather than established practice. OBJECTIVE: In view of the rapid developments in the field of neurophysiological basics of pruritus, the aim is to clarify how these new concepts can be brought in line with clinical understanding. MATERIALS AND METHODS: A review is provided. RESULTS: After the peripheral and spinal processing pathways for pruritus in the mouse were characterized with molecular markers, we are currently working on the translation of this information to the only functionally defined nerve fiber classes in humans. However, it is still unclear whether these processing pathways are crucial for the explanation of chronic pruritus in patients, since inflammation or neuropathy can significantly alter nerve populations and neuronal networks. Therefore, molecular target structures, which have emerged from results of basic research, need to be verified in patients. The gold standard, however, remains the patient with clinical observation and testing. Specific stimulation methods from neurophysiology can help to test hypotheses from basic research directly on patients, while also providing impulses for further development of research concepts. CONCLUSIONS: Translation in medical research is now perceived by many researchers as a hackneyed buzzword. In the field of pruritus research, however, the exchange of results and concepts based on the mutual appreciation of expertise appears attractive, highly relevant, and promising.


Assuntos
Neurofisiologia , Prurido , Animais , Humanos , Inflamação , Camundongos
19.
J Clin Neurophysiol ; 37(3): 208-210, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358247

RESUMO

Patients with intensive care unit-acquired weakness have an increased risk of prolonged mechanical ventilation, which is a risk factor for prolonged stay and mortality. The most common cause of this problem is weakness of the diaphragm, which can derive from phrenic nerve injury associated with critical neuropathy, or with the complex multiorgan failure/systemic respiratory response syndrome causing muscle fiber lesion. Two conventional neurophysiological techniques are useful to investigate the respiratory muscles, phrenic nerve conduction, and needle electromyography of the accessory respiratory muscles and diaphragm. Phrenic nerve stimulation is a standard noninvasive technique; amplitude of the motor response can be reduced because of muscle fiber inexcitability or axonal loss. Electromyography of the diaphragm is an invasive method but is safe if performed as indicated. It can reveal neurogenic or myopathic motor units. Although these neurophysiological methods have limitations in the investigation of intensive care unit patients with severe respiratory involvement, normal phrenic nerve responses should exclude marked axonal loss and indicate a better prognosis.


Assuntos
Cuidados Críticos/métodos , Diafragma/fisiopatologia , Debilidade Muscular/diagnóstico , Debilidade Muscular/fisiopatologia , Neurofisiologia/métodos , Eletromiografia/métodos , Feminino , Humanos , Unidades de Terapia Intensiva , Nervo Frênico/fisiopatologia
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