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1.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 45(4): 318-326, Aug. 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1513820

RESUMEN

Objectives: To explore differences in regional cortical morphometric structure between adolescents at risk for depression or with current depression. Methods: We analyzed cross-sectional structural neuroimaging data from a sample of 150 Brazilian adolescents classified as low-risk (LR) (n=50) or high-risk (HR) for depression (n=50) or with current depression (n=50) through a vertex-based approach with measurements of cortical volume (CV), surface area (SA), and cortical thickness (CT). Differences between groups in subcortical volume and in the organization of networks of structural covariance were also explored. Results: No significant differences in brain structure between groups were observed in whole-brain vertex-wise CV, SA, or CT. Also, no significant differences in subcortical volume were observed between risk groups. In relation to the structural covariance network, there was an indication of an increase in the hippocampus betweenness centrality index in the HR group network compared to the LR and current depression group networks. However, this result was only statistically significant when applying false discovery rate correction for nodes within the affective network. Conclusion: In an adolescent sample recruited using an empirically based composite risk score, no major differences in brain structure were detected according to the risk and presence of depression.

2.
Braz J Psychiatry ; 2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37243979

RESUMEN

OBJECTIVE: To explore differences in regional cortical morphometric structure between adolescents at risk for depression or with current depression. METHODS: We analyzed cross-sectional structural neuroimaging data from a sample of 150 Brazilian adolescents classified as low-risk (n=50) or high-risk for depression (n=50) or with current depression (n=50) through a vertex-based approach with measurements of cortical volume, surface area and thickness. Differences between groups in subcortical volumes and in the organization of networks of structural covariance were also explored. RESULTS: No significant differences in brain structure between groups were observed in whole-brain vertex-wise cortical volume, surface area or thickness. Also, no significant differences in subcortical volume were observed between risk groups. In relation to the structural covariance network, there was an indication of an increase in the hippocampus betweenness centrality index in the high-risk group network compared to the low-risk and current depression group networks. However, this result was only statistically significant when applying false discovery rate correction for nodes within the affective network. CONCLUSION: In an adolescent sample recruited using an empirically based composite risk score, no major differences in brain structure were detected according to the risk and presence of depression.

3.
Front Neurol ; 13: 937231, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105774

RESUMEN

Background: Dual-task paradigms are a known tool to evaluate possible impairments in the motor and cognitive function in patients with multiple sclerosis (MS). A technique to evaluate the cortical function during movement is functional near-infrared spectroscopy (fNIRS). The evaluation of the MS course or its treatment by associating fNIRS with gait measurements may be flexible and low-cost; however, there are no feasibility studies in the literature using these combined techniques in early-stage patients with MS. Objective: To evaluate cortical hemodynamics using fNIRS and gait parameters in patients at early stages of MS and in healthy controls during a dual-task paradigm. Methods: Participants performed cognitive tasks while walking to simulate daily activities. Cortical activation maps and gait variability were used to evaluate differences between 19 healthy controls and 20 patients with MS. Results and conclusion: The results suggest an enhanced cortical activation in the motor planning areas already at the early stages of MS when compared to controls. We have also shown that a systematic analysis of the spatiotemporal gait variability parameters indicates differences in the patient population. The association of cortical and gait parameters may reveal possible compensatory mechanisms related to gait during dual tasking at the early stages of the disease.

4.
Internet Interv ; 26: 100472, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34697586

RESUMEN

This study evaluated how news with positive and negative content about COVID-19, as well as a relaxation pause, affect the emotional state. We also investigated the association between emotional state and practicing meditation/yoga, physical activity or having a mental disease. For that, a sample of 717 participants, recruited through social media, were randomly assigned to listen to negative or positive news about COVID-19. After that, both groups were guided through a short relaxation pause. Their emotional state was measured before they listened to the audios and after each audio. Mixed linear models were used to evaluate the effects of news group, relaxation pause, mental health and well-being practices. Negative news worsened their emotional state, whereas positive news improved it. A brief relaxation pause improved the effects of negative news content and may mitigate the effects of this valence of information. Practicing physical activity, meditation/yoga was associated with better emotional responses.

5.
Internet Interv ; 26: 100441, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34458106

RESUMEN

A cause of mental distress during the COVID-19 pandemic is media exposure, which can impact health care professionals (HCPs) who must keep up to date with the statistics and procedures to fight the outbreak. This study aimed to evaluate the effects of listening to negative and positive news about COVID-19 pandemic and a relaxation pause audio. For that, we measured the emotional state through Likert items in a scale developed to assess how anxious, stressed, hopeful, conscious about emotions, irritated, despondent, joyful, optimistic, and preoccupied, he or she was feeling in the moment of evaluation. In an online experiment, an HCPs sample of 245 participants were randomly assigned to either listen to negative or positive news contents about COVID-19. After that, both groups were guided by a relaxation pause activity in which they paid attention to the body and breath. They were assessed before and after listening to each audio. After listening to negative news, participants entered in a more negative emotional state than at baseline (p < 0.001) and compared with participants who listened to positive news (p < 0.001). Both groups improved their emotional state after performing the proposed brief relaxation (p < 0.001). These results show the importance of HCPs being aware and controlling the content of consumed news. A brief relaxation practice can mitigate the negative effects of consuming information with negative content.

6.
Brain Behav ; 11(8): e02178, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34302446

RESUMEN

BACKGROUND: Graph theory (GT) is a mathematical field that analyses complex networks that can be applied to neuroimaging to quantify brain's functional systems in Parkinson's disease (PD) and essential tremor (ET). OBJECTIVES: To evaluate the functional connectivity (FC) measured by the global efficiency (GE) of the motor network in PD and compare it to ET and healthy controls (HC), and correlate it to clinical parameters. METHODS: 103 subjects (54PD, 18ET, 31HC) were submitted to structural and functional MRI. A network was designed with regions of interest (ROIs) involved in motor function, and GT was applied to determine its GE. Clinical parameters were analyzed as covariates to estimate the impact of disease severity and medication on GE. RESULTS: GE of the motor circuit was reduced in PD in comparison with HC (p .042). Areas that most contributed to it were left supplementary motor area (SMA) and bilateral postcentral gyrus. Tremor scores correlated positively with GE of the motor network in PD subgroups. For ET, there was an increase in the connectivity of the anterior cerebellar network to the other ROIs of the motor circuit in comparison with PD. CONCLUSIONS: FC measured by the GE of the motor network is diminished in PD in comparison with HC, especially due to decreased connectivity of left SMA and bilateral postcentral gyrus. This finding supports the theory that there is a global impairment of the motor network in PD, and it does not affect just the basal ganglia, but also areas associated with movement modulation. The ET group presented an increased connectivity of the anterior cerebellar network to the other ROIs of the motor circuit when compared to PD, which reinforces what it is known about its role in this pathology.


Asunto(s)
Temblor Esencial , Enfermedad de Parkinson , Ganglios Basales , Temblor Esencial/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Enfermedad de Parkinson/diagnóstico por imagen , Temblor
7.
J Gerontol A Biol Sci Med Sci ; 76(2): 216-223, 2021 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-32427282

RESUMEN

Gait initiation is a daily challenge even for healthy individuals as it requires the timely coupling between the automatic anticipatory postural adjustment (APA) and the voluntary step according to the context. Modulation of this motor event has been thought to involve higher level brain control, including cognitive inhibitory circuitries. Despite the known participation of the supplementary motor area (SMA) in the modulation of some parameters of APA, the participation of areas controlling inhibition during gait initiation still needs to be investigated. In this study, the hemodynamic responses of the SMA and dorsolateral prefrontal cortex (DLPFC) were assessed using functional near-infrared spectroscopy (fNIRS) during a gait initiation task under cognitive conflict to select the foot to step (congruent [CON] and incongruent [INC] conditions). The older group (OG) showed worse inhibitory control than the young group (YG) along with more impairments in APA parameters. OG also had a lower amplitude of hemodynamic responses in both areas than YG in the INC. The INC increased the correlation between SMA and DLPFC only in the YG. Aging seems to impair the interaction between the hemodynamic responses of SMA and DLPFC, which influences APA performance in gait initiation under cognitive conflict.


Asunto(s)
Envejecimiento/fisiología , Envejecimiento/psicología , Corteza Motora/irrigación sanguínea , Corteza Motora/fisiología , Corteza Prefrontal/irrigación sanguínea , Corteza Prefrontal/fisiología , Anciano , Fenómenos Biomecánicos , Cognición/fisiología , Conflicto Psicológico , Estudios Transversales , Femenino , Neuroimagen Funcional , Marcha/fisiología , Hemodinámica , Humanos , Masculino , Corteza Motora/diagnóstico por imagen , Equilibrio Postural/fisiología , Corteza Prefrontal/diagnóstico por imagen , Espectroscopía Infrarroja Corta , Adulto Joven
8.
Einstein (Sao Paulo) ; 18: eAO6127, 2020.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-33295429

RESUMEN

OBJECTIVE: To estimate coronavirus disease 2019-related information consumption and related implications for health care professionals (medical and nonmedical personnel) during the pandemic. METHODS: A cross-sectional on-line survey was distributed to employees of a major health care institution located in São Paulo, Brazil between April 3 and April 10, 2020. Data were analyzed using descriptive statistics. RESULTS: The sample comprised 2,646 respondents. Most participants (44.4%) reported excessive or almost excessive access to information about the novel coronavirus and 67.6% reported having increased their average time spent on social media. When asked how frequently they consider it was easy to determine the reliability of information, "sometimes" corresponded to 43.2% of the answers in contrast to 14.6% responding "always". Answers related to potential signs of information overload associated with the pandemic indicated that 31% of respondents felt stressed by the amount of information they had to keep up with almost every day or always. Overall, 80.0% of respondents reported having experienced at least one of the following symptoms: headache, eye twitching, restlessness or sleeping difficulty. The frequency of symptoms was higher among participants with a more negative information processing style regarding when dealing with large volumes of information relative to those with a positive information processing style. Likewise, symptoms were more frequently reported by participants who had increased their social media access relative to those reporting reduced access during the pandemic. CONCLUSION: Our survey provides a description of how health professionals consume COVID-19 related information during the pandemic, and suggests that excessive information exposure and high processing demands may impose psychological distress and affect mental health.


Asunto(s)
COVID-19 , Adulto , Brasil/epidemiología , Estudios Transversales , Femenino , Sector de Atención de Salud , Humanos , Internet , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , SARS-CoV-2 , Encuestas y Cuestionarios
9.
Einstein (Säo Paulo) ; 18: eAO6127, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1142870

RESUMEN

ABSTRACT Objective: To estimate coronavirus disease 2019-related information consumption and related implications for health care professionals (medical and nonmedical personnel) during the pandemic. Methods: A cross-sectional on-line survey was distributed to employees of a major health care institution located in São Paulo, Brazil between April 3 and April 10, 2020. Data were analyzed using descriptive statistics. Results: The sample comprised 2,646 respondents. Most participants (44.4%) reported excessive or almost excessive access to information about the novel coronavirus and 67.6% reported having increased their average time spent on social media. When asked how frequently they consider it was easy to determine the reliability of information, "sometimes" corresponded to 43.2% of the answers in contrast to 14.6% responding "always". Answers related to potential signs of information overload associated with the pandemic indicated that 31% of respondents felt stressed by the amount of information they had to keep up with almost every day or always. Overall, 80.0% of respondents reported having experienced at least one of the following symptoms: headache, eye twitching, restlessness or sleeping difficulty. The frequency of symptoms was higher among participants with a more negative information processing style regarding when dealing with large volumes of information relative to those with a positive information processing style. Likewise, symptoms were more frequently reported by participants who had increased their social media access relative to those reporting reduced access during the pandemic. Conclusion: Our survey provides a description of how health professionals consume COVID-19 related information during the pandemic, and suggests that excessive information exposure and high processing demands may impose psychological distress and affect mental health.


RESUMO Objetivo: Estimar o consumo de informações relacionadas com doença do novo coronavírus e seus efeitos em profissionais do setor da saúde durante a pandemia. Métodos: Um questionário on-line foi distribuído para funcionários de uma instituição de saúde em São Paulo, Brasil, entre 3 e 10 de abril de 2020. Os dados foram analisados com estatísticas descritivas. Resultados: Foram incluídos nas análises 2.646 participantes. A maioria (44,4%) reportou ter acessado uma quantidade excessiva ou próxima de excessiva sobre o novo coronavírus, e 67,6% reportaram ter aumentado seu tempo médio em mídias sociais. Quando perguntados se era fácil determinar o que era informação confiável, 43,2% responderam "às vezes", comparados com 14,6% que responderam "sempre". Sobre os possíveis sinais de sobrecarga de informação associada com a pandemia, 31% sempre ou quase todos os dias se sentiram estressados com a quantidade de informações que tinham que acompanhar. Entre os respondentes, 80,0% reportaram sentir pelo menos um sintoma como dor de cabeça, espasmos oculares, inquietação ou dificuldade para dormir. Participantes com um estilo mais negativo de lidar com muitas informações também reportaram maior proporção de sintomas que os participantes com estilo positivo. De forma semelhante, participantes que aumentaram seu acesso a mídias sociais reportaram maior proporção de sintomas do que os que diminuíram seu acesso durante a pandemia. Conclusão: Nossa pesquisa fornece uma descrição de como os indivíduos consomem informações relacionadas com a doença do novo coronavirus durante a pandemia e sugere que a exposição a uma quantidade excessiva de informações e as elevadas demandas podem impor sofrimento psicológico e afetar a saúde mental.


Asunto(s)
COVID-19 , Brasil/epidemiología , Estudios Transversales , Encuestas y Cuestionarios , Reproducibilidad de los Resultados , Sector de Atención de Salud , Internet , SARS-CoV-2 , Persona de Mediana Edad
10.
Front Physiol ; 10: 1302, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31681012

RESUMEN

The development of motor response inhibition is critical during preschool years and has been associated with an improvement in gross motor coordination in this population. However, the assessment of inhibitory abilities in young children is challenging in terms of task selection and subject engagement, especially when investigating foot responses. Thus, the aim of this study was to describe a child-friendly Go/No-go paradigm to assess inhibitory control of foot based on a dance mat protocol. In this method, Go and No-go stimuli are modeled in the context of a fishing game, and behavioral responses are assessed by recording the latency to touch the mat and the accuracy of the touches. In this protocol article, we (1) describe the stages of the experimental set-up, (2) provide an illustrative data collection example in a sample of children aged 3-4 years, and (3) describe how to process the data generated. The utilization of the dance mat provides a feasible tool for researchers interested in studying the development of motor inhibitory control of foot in preschoolers. Potential applications of this protocol may include studies on developmental differences between hand and foot specialization, sports-related performance and neuroimaging.

11.
Front Aging Neurosci ; 11: 158, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31312135

RESUMEN

Large-scale brain networks exhibit changes in functional connectivity during the aging process. Recent literature data suggests that Yoga and other contemplative practices may revert, at least in part, some of the aging effects in brain functional connectivity, including the Default Mode Network (DMN). The aim of this cross-sectional investigation was to compare resting-state functional connectivity of the medial prefrontal cortex (MPFC) and posterior cingulate cortex-precuneus (PCC-Precuneus) in long-term elderly Yoga practitioners and healthy paired Yoga-naïve controls. Two paired groups: yoga (Y-20 women, Hatha Yoga practitioners; practicing a minimum of twice a week with a frequency of at least 8 years) and a control group (C-20 women, Yoga-naïve, matched by age, years of formal education, and physical activity) were evaluated for: Mini Mental State Examination (MMSE), Beck Depression Inventory (BDI), Instrumental Activities of Daily Living (IADL), and open-eyes resting-state functional magnetic resonance imaging (fMRI)-seed to voxel connectivity analysis (CONN toolbox 17.f) with pre-processing-realignment and unwarping, slice-timing correction, segmentation, normalization, outlier detection, and spatial filtering. The analysis included a priori regions of interest (ROI) of DMN main nodes-MPFC and PCC-Precuneus. There was no difference between groups in terms of: age, years of formal education, MMSE, BDI and IADL. The Yoga group had a higher correlation between MPFC and the right angular gyrus (AGr), compared to the controls. Elderly women with at least 8 years of yoga practice presented greater intra-network anteroposterior brain functional connectivity of the DMN. This finding may contribute to the understanding of the influences of practicing Yoga for a healthier cognitive aging process.

12.
Arch Womens Ment Health ; 22(3): 375-381, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30112627

RESUMEN

The aims of the current study were to examine differences in brain responses to cognitive control in stressed and non-stressed women managers. Stress complaints are highly prevalent among active workers and play an important role in women managers mental health and cognitive functioning. Psychosocial stress has been associated with differential executive functions in this population, but little is known about the neural correlates underlying such differences. We examined brain responses of a particular group of workers that has been proposed to have a different response to stress as a function of their status (i.e., managers). Stressed (n = 19) and non-stressed women managers (n = 21) were scanned using functional magnetic resonance imaging (fMRI) during the performance of a cognitively demanding task. We used the Stroop color-word task to compare neural activation associated with the suppression of a predominant response tendency (i.e., word reading) and the initiation of an appropriate behavior alternative (i.e., naming word color). Despite similar behavioral performances, stressed managers exhibited increased activation in the occipital cortex during response inhibition. No regions were more activated in the non-stressed relative to the stressed group. This finding of greater activation has been interpreted as compensatory brain response to maintain performance in front of cognitive challenge.


Asunto(s)
Función Ejecutiva/fisiología , Liderazgo , Estrés Laboral/diagnóstico por imagen , Adulto , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Estrés Psicológico , Test de Stroop
13.
Brain Imaging Behav ; 13(5): 1418-1426, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30182274

RESUMEN

Quality of life is an important issue concerning people all over the world and affecting patients in the mental health field. When considering the potential neural links between quality of life and the brain, a brain network that comes into mind is the default mode network (DMN). Its architecture and function has been investigated in relation to various research fields including social and emotional cognition, meditation and neuropsychiatric disorders as well as happiness. In this cross-sectional study we investigated the relationship between various quality of life domains (physiological, psychological, social and environmental) and the functional connectivity of the default mode network at rest in a sample of 42 healthy working female managers. The results indicate that there is a significant association between the social quality of life domain and the functional connectivity of the default mode network. Post-hoc analysis revealed that high social quality of life scores were associated with right-left lateral parietal hypoconnectivity. By adopting a wide ranging perspective, our study approaches to fundamental research about quality of life but so far only applied on a female subgroup. As far as we know, it is the first to analyze the neuronal correlates of quality of life in the brain and therefore sets an initial step in its investigation.


Asunto(s)
Mapeo Encefálico , Encéfalo , Vías Nerviosas/fisiología , Calidad de Vida/psicología , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Ambiente , Femenino , Humanos , Imagen por Resonancia Magnética , Apoyo Social
14.
Front Psychol ; 9: 1840, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30364351

RESUMEN

Paralleling two decades of growth in the emergent field known as educational neuroscience is an increasing concern that educational practices and programs should be evidence-based, however, the idea that neuroscience could potentially influence education is controversial. One of the criticisms, regarding applications of the findings produced in this discipline, concerns the artificiality of neuroscientific experiments and the oversimplified nature of the tests used to investigate cognitive processes in educational contexts. The simulations may not account for all of the variables present in real classroom activities. In this study, we aim to get a step closer to the formation of data-supported classroom methodologies by employing functional near-infrared spectroscopy in various experimental paradigms. First, we present two hyperscanning scenarios designed to explore realistic interdisciplinary contexts, i.e., the classroom. In a third paradigm, we present a case study of a single student evaluated with functional near-infrared spectroscopy and mobile eye-tracking glasses. These three experiments are performed to provide proofs of concept for the application of functional near-infrared spectroscopy in scenarios that more closely resemble authentic classroom routines and daily activities. The goal of our study is to explore the potential of this technique in hopes that it offers insights in experimental design to investigate teaching-learning processes during teacher-student interactions.

15.
Sci Rep ; 8(1): 3341, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29463928

RESUMEN

The employment of functional near-infrared spectroscopy (fNIRS) as a method of brain imaging has increased over the last few years due to its portability, low-cost and robustness to subject movement. Experiments with fNIRS are designed in the face of a limited number of sources and detectors (optodes) to be positioned on selected portion(s) of the scalp. The optodes locations represent an expectation of assessing cortical regions relevant to the experiment's hypothesis. However, this translation process remains a challenge for fNIRS experimental design. In the present study, we propose an approach that automatically decides the location of fNIRS optodes from a set of predefined positions with the aim of maximizing the anatomical specificity to brain regions-of-interest. The implemented method is based on photon transport simulations on two head atlases. The results are compiled into the publicly available "fNIRS Optodes' Location Decider" (fOLD). This toolbox is a first-order approach to bring the achieved advancements of parcellation methods and meta-analyses from functional magnetic resonance imaging to more precisely guide the selection of optode positions for fNIRS experiments.


Asunto(s)
Encéfalo/diagnóstico por imagen , Neuroimagen Funcional/métodos , Dispositivos Ópticos , Espectroscopía Infrarroja Corta/métodos
16.
Front Syst Neurosci ; 12: 74, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30697151

RESUMEN

The cerebral cortex and the cerebellum are spatially remote areas that are connected by complex circuits that link both primary and associative areas. Previous studies have revealed abnormalities in autism spectrum disorder (ASD); however, it is not clear whether cortico-cerebellar connectivity is differentially manifested in the disorder. To explore this issue, we investigated differences in intrinsic cortico-cerebellar functional connectivity between individuals with typical development (TD) and those with ASD. To this end, we used functional magnetic resonance imaging (fMRI) of 708 subjects under a resting state protocol provided by the ABIDE I Consortium. We found that people with ASD had diminished functional connectivity between the cerebellum and the following cortical regions: (i) right fusiform gyrus, (ii) right postcentral gyrus, (iii) right superior temporal gyrus, (iv) right middle temporal gyrus, and (v) left middle temporal gyrus. All of these regions are involved in many cognitive systems that contribute to commonly affected functions in ASD. For right fusiform gyrus, right superior temporal gyrus, and left middle temporal gyrus, we reproduced the results in an independent cohort composed of 585 subjects of the ABIDE II Consortium. Our results points toward a consistent atypical cortico-cerebellar connectivity in ASD.

17.
Neurophotonics ; 5(1): 011002, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28840166

RESUMEN

Several functional near-infrared spectroscopy (fNIRS) studies report their findings based on changes of a single chromophore, usually concentration changes of oxygenated hemoglobin ([[Formula: see text]]) or deoxygenated hemoglobin (HHb). However, influence of physiological actions may differ depending on which element is considered and the assumption that the chosen measure correlates with the neural response of interest might not hold. By assessing the correlation between [[Formula: see text]] and [HHb] in task-evoked activity as well as resting-state data, we identified a spatial dependency of non-neuronal hemodynamic changes in the anterior temporal region of the human head. Our findings support the importance of reporting and discussing fNIRS outcomes obtained with both chromophores ([[Formula: see text]] and [HHb]), in particular, for studies concerning the anterior temporal region of the human head. This practice should help to achieve a physiologically correct interpretation of the results when no measurements with short-distance channels are available while employing continuous-wave fNIRS systems.

18.
Gait Posture ; 56: 112-118, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28544947

RESUMEN

Walkers are commonly prescribed worldwide to individuals unable to walk independently. Walker usage leads to improved postural control and voluntary movement during step. In the present study, we aimed to provide a concept-proof on the feasibility of an event-related protocol integrating the analyses of biomechanical variables of step initiation and functional near-infrared spectroscopy (fNIRS) to measure activation of the supplementary motor area (SMA) while using a walker. Healthy young participants were tested while stepping with versus without the use of the walker. Behavioral analysis showed that anticipatory postural adjustments (APA) decreased when supporting the body weight on the walker. Delta (without-with) of activation magnitude of the muscle tibialis anterior was positively correlated to the delta of deoxyhemoglobin concentration changes in the SMA. The novelty of this study is the development of a protocol to assess brain function together with biomechanical analysis during the use of a walker. The method sheds light to the potential utility of combining fNIRS and biomechanical assessment during assistive step initiation, which can represent a new opportunity to study populations with mobility deficits.


Asunto(s)
Corteza Motora/fisiología , Desempeño Psicomotor , Andadores , Caminata , Adulto , Estudios de Factibilidad , Neuroimagen Funcional , Hemoglobinas/metabolismo , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Corteza Motora/irrigación sanguínea , Valores de Referencia , Espectroscopía Infrarroja Corta , Adulto Joven
19.
J Biomed Opt ; 22(4): 46010, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28451693

RESUMEN

Functional near-infrared spectroscopy (fNIRS) is currently one of the most promising tools in the neuroscientific research to study brain hemodynamics during naturalistic social communication. The application of fNIRS by studies in this field of knowledge has been widely justified by its strong resilience to motion artifacts, including those that might be generated by communicative head and facial movements. Previous studies have focused on the identification and correction of these artifacts, but a quantification of the differential contribution of common communicative movements on the quality of fNIRS signals is still missing. We assessed the impact of four movements (nodding head up and down, reading aloud, nodding head sideways, and raising eyebrows) performed during rest and task conditions on two metrics of signal quality control: an estimative of signal-to-noise performance and the negative correlation between oxygenated and deoxygenated hemoglobin (oxy-Hb and deoxy-Hb). Channel-wise group analysis confirmed the robustness of the fNIRS technique to head nodding movements but showed a large effect of raising eyebrows in both signal quality control metrics, both during task and rest conditions. Reading aloud did not disrupt the expected anticorrelation between oxy-Hb and deoxy-Hb but had a relatively large effect on signal-to-noise performance. These findings may have implications to the interpretation of fNIRS studies examining communicative processes.


Asunto(s)
Comunicación , Cejas/fisiología , Expresión Facial , Movimientos de la Cabeza , Cabeza/fisiología , Espectroscopía Infrarroja Corta/métodos , Adulto , Artefactos , Gestos , Hemoglobinas/química , Humanos , Masculino , Oxígeno/química , Oxihemoglobinas/química , Control de Calidad , Procesamiento de Señales Asistido por Computador , Adulto Joven
20.
J Psychiatr Res ; 69: 142-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26343606

RESUMEN

Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions characterized by atypical structural and functional brain connectivity. Complex network analysis has been mainly used to describe altered network-level organization for functional systems and white matter tracts in ASD. However, atypical functional and structural connectivity are likely to be also linked to abnormal development of the correlated structure of cortical gray matter. Such covariations of gray matter are particularly well suited to the investigation of the complex cortical pathology of ASD, which is not confined to isolated brain regions but instead acts at the systems level. In this study, we examined network centrality properties of gray matter networks in adults with ASD (n = 84) and neurotypical controls (n = 84) using graph theoretical analysis. We derived a structural covariance network for each group using interregional correlation matrices of cortical volumes extracted from a surface-based parcellation scheme containing 68 cortical regions. Differences between groups in closeness network centrality measures were evaluated using permutation testing. We identified several brain regions in the medial frontal, parietal and temporo-occipital cortices with reductions in closeness centrality in ASD compared to controls. We also found an association between an increased number of autistic traits and reduced centrality of visual nodes in neurotypicals. Our study shows that ASD are accompanied by atypical organization of structural covariance networks by means of a decreased centrality of regions relevant for social and sensorimotor processing. These findings provide further evidence for the altered network-level connectivity model of ASD.


Asunto(s)
Trastorno del Espectro Autista/patología , Encéfalo/patología , Adolescente , Adulto , Sustancia Gris/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Modelos Neurológicos , Vías Nerviosas/patología , Tamaño de los Órganos , Adulto Joven
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