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1.
Nat Commun ; 11(1): 5004, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020473

RESUMO

Adaptive brain function requires that sensory impressions of the social and natural milieu are dynamically incorporated into intrinsic brain activity. While dynamic switches between brain states have been well characterised in resting state acquisitions, the remodelling of these state transitions by engagement in naturalistic stimuli remains poorly understood. Here, we show that the temporal dynamics of brain states, as measured in fMRI, are reshaped from predominantly bistable transitions between two relatively indistinct states at rest, toward a sequence of well-defined functional states during movie viewing whose transitions are temporally aligned to specific features of the movie. The expression of these brain states covaries with different physiological states and reflects subjectively rated engagement in the movie. In sum, a data-driven decoding of brain states reveals the distinct reshaping of functional network expression and reliable state transitions that accompany the switch from resting state to perceptual immersion in an ecologically valid sensory experience.


Assuntos
Encéfalo/fisiologia , Filmes Cinematográficos , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Frequência Cardíaca/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Filmes Cinematográficos/classificação , Filmes Cinematográficos/estatística & dados numéricos , Percepção/fisiologia , Pupila/fisiologia , Descanso/fisiologia , Inquéritos e Questionários , Adulto Jovem
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4522-4526, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018999

RESUMO

Methods based exclusively on heart rate hardly allow to differentiate between physical activity, stress, relaxation, and rest, that is why an additional sensor like activity/movement sensor added for detection and classification. The response of the heart to physical activity, stress, relaxation, and no activity can be very similar. In this study, we can observe the influence of induced stress and analyze which metrics could be considered for its detection. The changes in the Root Mean Square of the Successive Differences provide us with information about physiological changes. A set of measurements collecting the RR intervals was taken. The intervals are used as a parameter to distinguish four different stages. Parameters like skin conductivity or skin temperature were not used because the main aim is to maintain a minimum number of sensors and devices and thereby to increase the wearability in the future.


Assuntos
Eletrocardiografia , Exercício Físico , Coração , Frequência Cardíaca , Descanso
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4547-4550, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019005

RESUMO

Non-contact electrode type electrocardiograph system was researched in various fields, but few products are commercially available. In this study, we proposed a sofa-type capacitive coupling electrocardiograph which has possibilities to be commercialized. The base system is a commercially available oval shape sofa that provides oxygen. We developed a capacitive coupling electrocardiograph and embedded it into the base system. The system gives feedback by measuring the ECG signal on stress relief during resting with taking oxygen provided by the sofa. In the capacitive coupling electrocardiograph, it is inevitable to develop a suitable active electrode for the target system, so we developed that comprised of a surface electrode, electronics, and metal case. The surface electrode was made of PCB with two layers of copper plate: the top layer is for coupling function (coated with AU), and the bottom layer plays a role as a shield. The fabricated active electrode module is embedded into the sofa. The purpose of the developed electrocardiograph is to measure HRV of sofa users. The measured HRV was compared with that from a reference system by various coupling distances (cotton cloth thickness) to guarantee the quality of measured signals. The comparison result shows that RRI correlation was mostly over 0.99, SDNN variation rate was mostly under 1%, and LF/HF variation rate was less than 1% in the tested thicknesses.


Assuntos
Eletrocardiografia , Oxigênio , Eletrodos , Descanso , Sono
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5450-5454, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019213

RESUMO

Sleep has been shown to be an indispensable and important component of patients' recovery process. Nonetheless, the sleep quality of patients in the Intensive Care Unit (ICU) is often low, due to factors such as noise, pain, and frequent nursing care activities. Frequent sleep disruptions by the medical staff and/or visitors at certain times might lead to disruption of the patient's sleep-wake cycle and can also impact the severity of pain. Examining the association between sleep quality and frequent visitation has been difficult, due to the lack of automated methods for visitation detection. In this study, we recruited 38 patients to automatically assess visitation frequency from captured video frames. We used the DensePose R-CNN (ResNet-101) model to calculate the number of people in the room in a video frame. We examined when patients are interrupted the most, and we examined the association between frequent disruptions and patient outcomes on pain and length of stay.Clinical Relevance- This study shows that rest disruptions can be automatically detected in the ICU, and such information can be used to better understand the sleep quality of patients in the ICU.


Assuntos
Estado Terminal , Transtornos do Sono-Vigília , Humanos , Unidades de Terapia Intensiva , Descanso , Sono
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2557-2560, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018528

RESUMO

The heat production of cardiac muscle, determined by calorimetry, can be used as a measure of cardiac metabolism. However, heat produced while a muscle is actively-shortening, thereby performing force-length work, comprises both active and basal metabolic processes. In this paper, we present a method for post-experimental processing of calorimetric measurements of muscle heat production, that uncovers and compensates for the measured basal heat rate during work. In this method, the relationships between muscle length, velocity of length change and muscle heat output are coupled with a simulation of the measurement instrument, providing a model-based estimate of change of measured basal heat while the muscle is performing work. We demonstrate the use of this technique in an experiment conducted on a working cardiac muscle sample. The ability to identify the various components of heat release in these muscles provides useful insight into their mechanical and energetic capabilities.


Assuntos
Miocárdio , Termogênese , Metabolismo Basal , Calorimetria , Descanso
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2853-2856, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018601

RESUMO

In more recent times, the network perspective study of the human brain has expanded enormously due to the advancements in the field of network neuroscience. Existing methods to form the functional connectivity from the multichannel EEG leads to a fully connected network. Representation of a fully connected functional network with a significant functional network (SFN) can help to characterize and quantify the complex brain networks. Further, it can also provide novel insight into the brain cognition analysis and is crucial in several brain network-based applications. This paper presents a framework to find the SFN corresponding to any event from its fully connected network. Using the phase-locking value (PLV) in EEG we first identify the difference PLV of an event to the rest. Based on the difference PLV, we then identify the reactive band and event-associated most reactive pairs (MRPs). The SFNs corresponding to their events is then formed with the identified MRPs. The proposed method is employed on 'database for emotion analysis using physiological signals (DEAP)' data set to find the SFNs associated with emotions. Comparable state-of-the-art multiple emotion classification accuracies are obtained with the identified SFNs. Results show that the proposed methods can be used as a general thresholding technique to identify the event-related SFNs which are crucial in brain network-based applications.


Assuntos
Encéfalo , Eletroencefalografia , Encéfalo/diagnóstico por imagem , Cognição , Emoções , Humanos , Descanso
7.
PLoS One ; 15(7): e0236795, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735625

RESUMO

Osteoarthritis in cats is more prevalent because cats are living longer with advancement in veterinary medicine. Objective evaluation of behavioral changes in cats with osteoarthritis can facilitate an early diagnosis. The objective of this study was to investigate the utility of a novel activity monitor for analyzing physical activities and sleep quality in cats. First, a novel activity monitor (Plus Cycle®; JARMeC, Kanagawa, Japan), with a built-in three-directional accelerometer and an air pressure sensor specifically designed for cats, was compared to a human activity monitor (Actical®; Philips Respironics, OR, USA) previously used in cats (n = 10). Second, the validity of the measurement accuracy of the amount of physical activity, the number of vibrations, the number of jumps, and the resting and sleeping time was evaluated using Plus Cycle® in healthy cats (n = 6). Finally, the effects of gender and age of cats and time of day on the amount of physical activity, the number of vibrations, the number of jumps, and the resting and sleeping time were investigated in client-owned cats (n = 61). There were strong correlations between Plus Cycle® and Actical® in total activity (p < 0.05) and activity intensity (p < 0.05). When the physical activities were measured using Plus Cycle® in healthy cats, those data were quantified with high accuracy. In addition, it was also found to be very accurate in discriminating the resting and sleeping conditions of cats. In client-owned cats, there were no significant differences with respect to gender in any measured traits. The amount of physical activity and the number of jumps significantly decreased with the age of the cat. In contrast, the resting and sleeping times significantly increased with the age of the cat. In conclusion, Plus Cycle® can accurately and objectively assess physical activities and sleep quality with age of the cat, suggesting that this novel activity monitor can be used to manage the feline musculoskeletal health.


Assuntos
Monitores de Aptidão Física/veterinária , Monitorização Fisiológica/veterinária , Animais , Artrite/veterinária , Doenças do Gato , Gatos , Japão , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Descanso , Sono
8.
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
9.
PLoS One ; 15(8): e0237348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764818

RESUMO

Active workstations are associated with improved health outcomes, but differences in cognitive and typing outcomes between the types of active workstations are unclear. We addressed two main questions: (1) Are there differences in cognitive and typing performance between seated and active workstations? (2) Are there differences in cognitive and typing performance between cycling and treadmill workstations, specifically? Participants included 137 healthy young adults (74 female, mean age = 20.8 years) who completed two sessions. At session one (baseline), all participants completed cognitive and typing tests including the Rey-Auditory Verbal Learning Test, Paced Auditory Serial Addition Test, a typing test, and a flanker task while sitting at rest. At session two, participants were randomized to an active workstation group (treadmill or cycling desk) during which they performed the tests listed above in a randomized fashion, using alternate versions when available. Participants showed significantly better attention and cognitive control scores during the active session as compared to the seated session, but worse verbal memory scores during the active session. Participants were faster and more accurate at typing during the active session relative to the seated session. There were no significant differences between cycling or treadmill workstations on any cognitive or typing outcomes. Improvements during active sessions may be influenced by practice effects, although alternate forms were used when possible. We conclude that active workstations do not seem to largely impact cognitive abilities, with the exception of a slight decrease in verbal memory performance. Findings suggest active workstations, whether walking or cycling, are useful to improve physical activity, particularly when completing tasks that do not require verbal memory recall.


Assuntos
Cognição , Exercício Físico , Descanso , Adulto , Atenção , Ciclismo , Feminino , Humanos , Masculino , Postura Sentada , Caminhada , Adulto Jovem
10.
PLoS One ; 15(7): e0236025, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32658929

RESUMO

BACKGROUND: The need to control for the potential influence of menstrual cycle phase on resting metabolism (RMR) places a burden on research participants who must self-report onset of menstruation and researchers who must schedule metabolic testing accordingly. PURPOSE: To systematically review and analyze existing research to determine the effect of menstrual cycle on RMR. METHODS: We searched PubMed, CINAHL, MEDLINE, SPORTDiscus, and Scopus databases using the search terms "menstrual cycle and metabolic rate" and "menstrual cycle and energy expenditure." Eligibility criteria were English language, single-group repeated measures design, and RMR as either a primary or secondary outcome. Risk of bias was assessed based on study sample, measurement, and control of confounders. Differences between the follicular and luteal phases of the menstrual cycle were analyzed using the standardized mean difference in effect size. RESULTS: Thirty English-language studies published between 1930 and December 2019 were included in the systematic review, and 26 studies involving 318 women were included in the meta-analysis. Overall, there was a small but significant effect favoring increased RMR in the luteal phase (ES = 0.33; 95% CI = 0.17, 0.49, p < 0.001). DISCUSSION: Limitations include risk of bias regarding measurement of both menstrual cycle and RMR. Sample sizes were small and studies did not report control of potential confounders. Sub-group analysis demonstrated that in more recent studies published since 2000, the effect of menstrual phase was reduced and not statistically significant (ES = 0.23; 95% CI = -0.00, 0.47; p = 0.055). Until larger and better designed studies are available, based on our current findings, researchers should be aware of the potential confounding influence of the menstrual cycle and control for it by testing consistently in one phase of the cycle when measuring RMR in pre-menopausal women.


Assuntos
Metabolismo Basal , Ciclo Menstrual , Descanso/fisiologia , Feminino , Humanos
11.
Nat Commun ; 11(1): 3480, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32661242

RESUMO

Researchers have observed large-scale neural meta-state transitions that align to narrative events during movie-viewing. However, group or training-derived priors have been needed to detect them. Here, we introduce methods to sample transitions without any priors. Transitions detected by our methods predict narrative events, are similar across task and rest, and are correlated with activation of regions associated with spontaneous thought. Based on the centrality of semantics to thought, we argue these transitions serve as general, implicit neurobiological markers of new thoughts, and that their frequency, which is stable across contexts, approximates participants' mentation rate. By enabling observation of idiosyncratic transitions, our approach supports many applications, including phenomenological access to the black box of resting cognition. To illustrate the utility of this access, we regress resting fMRI transition rate and movie-viewing transition conformity against trait neuroticism, thereby providing a first neural confirmation of mental noise theory.


Assuntos
Encéfalo/fisiologia , Neuroticismo/fisiologia , Adulto , Mapeamento Encefálico , Cognição/fisiologia , Neurociência Cognitiva/métodos , Intervalos de Confiança , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Análise de Componente Principal , Descanso/fisiologia
12.
Rev Mal Respir ; 37(7): 608-612, 2020 09.
Artigo em Francês | MEDLINE | ID: mdl-32600900
13.
PLoS Biol ; 18(7): e3000789, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32614823

RESUMO

In the absence of any task, both the brain and spinal cord exhibit spontaneous intrinsic activity organised in a set of functionally relevant neural networks. However, whether such resting-state networks (RSNs) are interconnected across the brain and spinal cord is unclear. Here, we used a unique scanning protocol to acquire functional images of both brain and cervical spinal cord (CSC) simultaneously and examined their spatiotemporal correspondence in humans. We show that the brain and spinal cord activities are strongly correlated during rest periods, and specific spinal cord regions are functionally linked to consistently reported brain sensorimotor RSNs. The functional organisation of these networks follows well-established anatomical principles, including the contralateral correspondence between the spinal hemicords and brain hemispheres as well as sensory versus motor segregation of neural pathways along the brain-spinal cord axis. Thus, our findings reveal a unified functional organisation of sensorimotor networks in the entire central nervous system (CNS) at rest.


Assuntos
Encéfalo/fisiologia , Descanso/fisiologia , Medula Espinal/fisiologia , Adulto , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Feminino , Humanos , Masculino , Rede Nervosa/fisiologia
14.
PLoS Biol ; 18(7): e3000733, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32649707

RESUMO

Recent resting-state functional MRI (fMRI) studies have revealed that the global signal (GS) exhibits a nonuniform spatial distribution across the gray matter. Whether this topography is informative remains largely unknown. We therefore tested rest-task modulation of GS topography by analyzing static GS correlation and dynamic coactivation patterns in a large sample of an fMRI dataset (n = 837) from the Human Connectome Project. The GS topography in the resting state and in seven different tasks was first measured by correlating the GS with the local time series (GSCORR). In the resting state, high GSCORR was observed mainly in the primary sensory and motor regions, whereas low GSCORR was seen in the association brain areas. This pattern changed during the seven tasks, with mainly decreased GSCORR in sensorimotor cortex. Importantly, this rest-task modulation of GSCORR could be traced to transient coactivation patterns at the peak period of GS (GS-peak). By comparing the topography of GSCORR and respiration effects, we observed that the topography of respiration mimicked the topography of GS in the resting state, whereas both differed during the task states; because of such partial dissociation, we assume that GSCORR could not be equated with a respiration effect. Finally, rest-task modulation of GS topography could not be exclusively explained by other sources of physiological noise. Together, we here demonstrate the informative nature of GS topography by showing its rest-task modulation, the underlying dynamic coactivation patterns, and its partial dissociation from respiration effects during task states.


Assuntos
Mapeamento Encefálico , Imagem por Ressonância Magnética , Descanso/fisiologia , Processamento de Sinais Assistido por Computador , Análise e Desempenho de Tarefas , Adulto , Conectoma , Feminino , Humanos , Masculino , Prosencéfalo/fisiologia , Reprodutibilidade dos Testes , Respiração , Fatores de Tempo , Adulto Jovem
15.
Medicine (Baltimore) ; 99(28): e21125, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664139

RESUMO

OBJECTIVE: The aim of this study was to characterize the capability of detection of the resting state networks (RSNs) with functional magnetic resonance imaging (fMRI) in healthy subjects using a 1.5T scanner in a middle-income country. MATERIALS AND METHODS: Ten subjects underwent a complete blood-oxygen-level dependent imaging (BOLD) acquisition on a 1.5T scanner. For the imaging analysis, we used the spatial independent component analysis (sICA). We designed a computer tool for 1.5 T (or above) scanners for imaging processing. We used it to separate and delineate the different components of the RSNs of the BOLD signal. The sICA was also used to differentiate the RSNs from noise artifact generated by breathing and cardiac cycles. RESULTS: For each subject, 20 independent components (IC) were computed from the sICA (a total of 200 ICs). From these ICs, a spatial pattern consistent with RSNs was identified in 161 (80.5%). From the 161, 131 (65.5%) were fit for study. The networks that were found in all subjects were: the default mode network, the right executive control network, the medial visual network, and the cerebellar network. In 90% of the subjects, the left executive control network and the sensory/motor network were observed. The occipital visual network was present in 80% of the subjects. In 39 (19.5%) of the images, no any neural network was identified. CONCLUSIONS: Reproduction and differentiation of the most representative RSNs was achieved using a 1.5T scanner acquisitions and sICA processing of BOLD imaging in healthy subjects.


Assuntos
Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética/instrumentação , Rede Nervosa/diagnóstico por imagem , Descanso/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico/métodos , Desenho de Equipamento , Feminino , Seguimentos , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
17.
Gerokomos (Madr., Ed. impr.) ; 31(2): 71-75, jun. 2020.
Artigo em Espanhol | IBECS | ID: ibc-193886

RESUMO

OBJETIVO: Describir la participación del familiar cuidador para el confort de las personas mayores de 65 años hospitalizadas, según la percepción de las enfermeras y los familiares cuidadores en un hospital público de Lambayeque, Perú. MÉTODOS: Investigación cualitativa exploratoria descriptiva; la muestra fue de 20 informantes previo consentimiento informado. Los datos fueron recolectados mediante la entrevista semiestructurada y procesados según análisis de contenido temático. RESULTADOS: Emergieron tres categorías: a) participación en los cuidados básicos: confort del cuerpo; b) estrategias para el descanso y sueño: confort del ambiente; c) afecto, ánimo y fe: contribución al confort emocional y espiritual. CONCLUSIONES: La permanencia hospitalaria genera incomodidades en las personas adultas mayores, pero el familiar cuidador participa activamente en la satisfacción de las necesidades básicas como la higiene, alimentación, tendido de cama, evitación del dolor y de los ruidos, iluminación adecuada, seguridad, afecto, esperanza y fe; cuidados orientados a proporcionarles un entorno tranquilo y agradable que les ayuda en el descanso y sueño, la adaptación, la recuperación y la calidad de vida. Es indispensable que el personal de enfermería capacite al familiar cuidador y lo prepare para colaborar en el cuidado tanto en la hospitalización como en el hogar


OBJECTIVE: To describe the participation of the family caregiver for the comfort of people over 65 hospitalized, according to the perception of nurses and family caregivers in a public hospital in Lambayeque, Peru. METHODS: Descriptive exploratory qualitative research, the sample was 20 informants with informed consent. The data was collected through the semi-structured interview and processed according to thematic content analysis. RESULTS: Three categories emerged: a) Participation in basic care: Body comfort; b) Strategies for rest and sleep: Comfort of the environment; c) Affection, encouragement and faith: Contribution to emotional and spiritual comfort. CONCLUSIONS: The hospital stay generates discomfort in older adults, but the family caregiver actively participates in the satisfaction of basic needs such as hygiene, food, laying of bed, avoidance of pain and noise, adequate lighting, safety, affection, hope and faith; care oriented to provide a peaceful and pleasant environment that helps them in rest and sleep, adaptation, recovery and quality of life. It is essential that the nursing staff trains the family caregiver and prepares them to collaborate in the care of both the hospitalization and the home


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Cuidadores/psicologia , Conforto do Paciente , Percepção , Esgotamento Psicológico/psicologia , Enfermagem Geriátrica/educação , Cuidadores/tendências , Saúde da Família , Pesquisa Qualitativa , Descanso/psicologia , Sono , Afeto , Qualidade de Vida/psicologia
18.
J Sports Med Phys Fitness ; 60(7): 992-998, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32597616

RESUMO

BACKGROUND: The rest interval between sets can affect the responses to resistance training. Thus, the purpose of this study was to compare the effects of different rest intervals (RI) on volume, density, and rating of perceived exertion (RPE) when adopting a crescent pyramid (CP) system. METHODS: Twenty young women (21.1±2.6 years, 1.59±0.06 m, 58.5±9.3 kg) participated in this study. All participants performed three experimental sessions of the leg press exercise in 5 sets until voluntary muscular failure at 60%, 65%, 70%, 75%, and 80% of one-repetition maximum (1RM). A randomized and crossover design was used so that in each session one of three RI (RI-1 = 1 min, RI-2 = 2 min, and RI-3 = 3 min) was tested. RESULTS: The participants performed a significantly larger volume in the RI-3 (12820±3134 kg) when compared to RI-1 (10367±3053 kg) condition (P<0.05). The volume did not differ between RI-2 and RI-3 (P>0.05). The density was higher (P<0.05) in RI-1 (43.1±12.7 kg/s) when compared RI-2 (25.6±5.8 kg/s) and RI-3 (17.7±4.3 kg/s). The RI-2 presented higher density compared to RI-3 condition (P<0.05). The RPE was not different between the three conditions (P>0.05). CONCLUSIONS: The use of 2 minutes of rest between sets allowed the performance of a high volume-load and density of the session in young women. In addition, the three experimental sessions provided a high perception of effort.


Assuntos
Percepção/fisiologia , Esforço Físico/fisiologia , Treinamento de Resistência/métodos , Levantamento de Peso/fisiologia , Adulto , Estudos Cross-Over , Feminino , Humanos , Perna (Membro)/fisiologia , Descanso/fisiologia , Fatores de Tempo , Adulto Jovem
19.
PLoS One ; 15(6): e0235074, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569326

RESUMO

OBJECTIVES: It is commonly accepted that motor imagery (MI), i.e. the mental simulation of a movement, leads to an increased size of cortical motor evoked potentials (MEPs), although the magnitude of this effect differs between studies. Its impact on the spinal level is even more variable in the literature. Such discrepancies may be explained by many different experimental approaches. Therefore, the question of the optimal stimulation parameters to assess both spinal and corticospinal excitabilities remains open. METHODS: H-reflexes and MEPs of the triceps surae were evoked in 11 healthy subjects during MI, weak voluntary contraction (CON) and rest (REST). In each condition, the full recruitment curve from the response threshold to maximal potential was investigated. RESULTS: At stimulation intensities close to the maximal response, MEP amplitude was increased by CON compared to REST on the triceps surae. No effect of the different conditions was found on the H-reflex recruitment curve, except a small variation beyond maximal H-reflex in the soleus muscle. CONCLUSION: Based on our results, we recommend to assess corticospinal excitability between 70% and 100% of maximal MEP intensity instead of the classical use of a percentage of the motor threshold and to elicit H-reflexes on the ascending part of the recruitment curve.


Assuntos
Imagens, Psicoterapia , Contração Muscular/fisiologia , Tratos Piramidais/fisiologia , Descanso , Medula Espinal/fisiologia , Estimulação Magnética Transcraniana , Adulto , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Projetos Piloto
20.
World Neurosurg ; 138: 672-679, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32545020

RESUMO

OBJECTIVE: In this study, we considered the treatment of cognitive characteristics of Parkinson's subtypes under resting magnetic resonance imaging scans, and used magnetic resonance imaging to analyze brain activity characteristics of patients with Parkinson's subtypes at rest. METHODS: In this study, patients with neurological Parkinson's disease subtypes were selected: 27 patients in the tremor group, 33 patients in the orthostatic gastric instability group, and 3 patients with mild cognitive impairment and neuropathic Parkinson's disease. Scientific treatment was adopted. RESULTS: Nineteen patients had mild cognitive dysfunction tremor and unstable posture, and 23 of them had mild cognitive dysfunction. Fifteen healthy controls were subjected to resting state functional magnetic resonance imaging by plane echo imaging sequence scanning. Neurological diseases-Regional consistency analysis of brain regions in patients with Parkinson's disease increased, including the right lower lobe, while regional consistency analysis of brain regions decreased, including the right frontal gyrus, right middle anterior gyrus, and lateral cerebellum. CONCLUSIONS: The experimental results show that the local consistency analysis method based on resting magnetic resonance imaging scan can effectively detect the differences in early neural activity in patients with Parkinson's disease subtype cognitive impairment, and can effectively reflect the brain characteristics of Parkinson's disease.


Assuntos
Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Idoso , Estudos de Casos e Controles , Cognição , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Feminino , Neuroimagem Funcional , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Descanso , Tremor/fisiopatologia
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