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1.
Nat Commun ; 11(1): 4560, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917899

RESUMO

The rhesus macaque is an important model species in several branches of science, including neuroscience, psychology, ethology, and medicine. The utility of the macaque model would be greatly enhanced by the ability to precisely measure behavior in freely moving conditions. Existing approaches do not provide sufficient tracking. Here, we describe OpenMonkeyStudio, a deep learning-based markerless motion capture system for estimating 3D pose in freely moving macaques in large unconstrained environments. Our system makes use of 62 machine vision cameras that encircle an open 2.45 m × 2.45 m × 2.75 m enclosure. The resulting multiview image streams allow for data augmentation via 3D-reconstruction of annotated images to train a robust view-invariant deep neural network. This view invariance represents an important advance over previous markerless 2D tracking approaches, and allows fully automatic pose inference on unconstrained natural motion. We show that OpenMonkeyStudio can be used to accurately recognize actions and track social interactions.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Macaca mulatta/fisiologia , Movimento (Física) , Algoritmos , Animais , Fenômenos Biomecânicos , Aprendizado Profundo , Masculino , Modelos Animais , Movimento , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Redes Neurais de Computação
2.
Nat Commun ; 11(1): 4829, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973154

RESUMO

The computed tomography angiography (CTA) postprocessing manually recognized by technologists is extremely labor intensive and error prone. We propose an artificial intelligence reconstruction system supported by an optimized physiological anatomical-based 3D convolutional neural network that can automatically achieve CTA reconstruction in healthcare services. This system is trained and tested with 18,766 head and neck CTA scans from 5 tertiary hospitals in China collected between June 2017 and November 2018. The overall reconstruction accuracy of the independent testing dataset is 0.931. It is clinically applicable due to its consistency with manually processed images, which achieves a qualification rate of 92.1%. This system reduces the time consumed from 14.22 ± 3.64 min to 4.94 ± 0.36 min, the number of clicks from 115.87 ± 25.9 to 4 and the labor force from 3 to 1 technologist after five months application. Thus, the system facilitates clinical workflows and provides an opportunity for clinical technologists to improve humanistic patient care.


Assuntos
Angiografia/métodos , Vasos Sanguíneos/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Pescoço/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Idoso , Osso e Ossos/diagnóstico por imagem , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
3.
Nat Commun ; 11(1): 4854, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978383

RESUMO

Chronic imaging of neuronal networks in vitro has provided fundamental insights into mechanisms underlying neuronal function. Current labeling and optical imaging methods, however, cannot be used for continuous and long-term recordings of the dynamics and evolution of neuronal networks, as fluorescent indicators can cause phototoxicity. Here, we introduce a versatile platform for label-free, comprehensive and detailed electrophysiological live-cell imaging of various neurogenic cells and tissues over extended time scales. We report on a dual-mode high-density microelectrode array, which can simultaneously record in (i) full-frame mode with 19,584 recording sites and (ii) high-signal-to-noise mode with 246 channels. We set out to demonstrate the capabilities of this platform with recordings from primary and iPSC-derived neuronal cultures and tissue preparations over several weeks, providing detailed morpho-electrical phenotypic parameters at subcellular, cellular and network level. Moreover, we develop reliable analysis tools, which drastically increase the throughput to infer axonal morphology and conduction speed.


Assuntos
Rede Nervosa/fisiologia , Neurônios/fisiologia , Imagem Óptica/métodos , Análise de Célula Única/métodos , Animais , Axônios , Encéfalo , Células Cultivadas , Células-Tronco Pluripotentes Induzidas , Camundongos , Microeletrodos , Modelos Animais , Rede Nervosa/diagnóstico por imagem , Imagem Óptica/instrumentação , Ratos , Ratos Wistar , Gravação em Vídeo
4.
PLoS Biol ; 18(8): e3000800, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776945

RESUMO

Studies of neural processes underlying delay of gratification usually focus on prefrontal networks related to curbing affective impulses. Here, we provide evidence for an alternative mechanism that facilitates delaying gratification by mental orientation towards the future. Combining continuous theta-burst stimulation (cTBS) with functional neuroimaging, we tested how the right temporoparietal junction (rTPJ) facilitates processing of future events and thereby promotes delay of gratification. Participants performed an intertemporal decision task and a mental time-travel task in the MRI scanner before and after receiving cTBS over the rTPJ or the vertex (control site). rTPJ cTBS led to both stronger temporal discounting for longer delays and reduced processing of future relative to past events in the mental time-travel task. This finding suggests that the rTPJ contributes to the ability to delay gratification by facilitating mental representation of outcomes in the future. On the neural level, rTPJ cTBS led to a reduction in the extent to which connectivity of rTPJ with striatum reflected the value of delayed rewards, indicating a role of rTPJ-striatum connectivity in constructing neural representations of future rewards. Together, our findings provide evidence that the rTPJ is an integral part of a brain network that promotes delay of gratification by facilitating mental orientation to future rewards.


Assuntos
Corpo Estriado/fisiologia , Tomada de Decisões/fisiologia , Desvalorização pelo Atraso/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Lobo Temporal/fisiologia , Adulto , Mapeamento Encefálico , Corpo Estriado/anatomia & histologia , Corpo Estriado/diagnóstico por imagem , Feminino , Neuroimagem Funcional , Humanos , Comportamento Impulsivo/fisiologia , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Lobo Parietal/anatomia & histologia , Lobo Parietal/diagnóstico por imagem , Recompensa , Lobo Temporal/anatomia & histologia , Lobo Temporal/diagnóstico por imagem , Estimulação Magnética Transcraniana
5.
PLoS Comput Biol ; 16(8): e1007983, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745096

RESUMO

Many large-scale functional connectivity studies have emphasized the importance of communication through increased inter-region correlations during task states. In contrast, local circuit studies have demonstrated that task states primarily reduce correlations among pairs of neurons, likely enhancing their information coding by suppressing shared spontaneous activity. Here we sought to adjudicate between these conflicting perspectives, assessing whether co-active brain regions during task states tend to increase or decrease their correlations. We found that variability and correlations primarily decrease across a variety of cortical regions in two highly distinct data sets: non-human primate spiking data and human functional magnetic resonance imaging data. Moreover, this observed variability and correlation reduction was accompanied by an overall increase in dimensionality (reflecting less information redundancy) during task states, suggesting that decreased correlations increased information coding capacity. We further found in both spiking and neural mass computational models that task-evoked activity increased the stability around a stable attractor, globally quenching neural variability and correlations. Together, our results provide an integrative mechanistic account that encompasses measures of large-scale neural activity, variability, and correlations during resting and task states.


Assuntos
Encéfalo/fisiologia , Rede Nervosa/fisiologia , Potenciais de Ação/fisiologia , Adulto , Animais , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Macaca mulatta , Imagem por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Neurônios/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
6.
PLoS One ; 15(8): e0236883, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817642

RESUMO

While it is still not possible to describe the neuronal-level connections of the human brain, we can map the human connectome with several hundred vertices, by the application of diffusion-MRI based techniques. In these graphs, the nodes correspond to anatomically identified gray matter areas of the brain, while the edges correspond to the axonal fibers, connecting these areas. In our previous contributions, we have described numerous graph-theoretical phenomena of the human connectomes. Here we map the frequent complete subgraphs of the human brain networks: in these subgraphs, every pair of vertices is connected by an edge. We also examine sex differences in the results. The mapping of the frequent subgraphs gives robust substructures in the graph: if a subgraph is present in the 80% of the graphs, then, most probably, it could not be an artifact of the measurement or the data processing workflow. We list here the frequent complete subgraphs of the human braingraphs of 413 subjects (238 women and 175 men), each with 463 nodes, with a frequency threshold of 80%, and identify 812 complete subgraphs, which are more frequent in male and 224 complete subgraphs, which are more frequent in female connectomes.


Assuntos
Gráficos por Computador , Conectoma , Algoritmos , Axônios/metabolismo , Feminino , Humanos , Masculino , Rede Nervosa/citologia , Rede Nervosa/diagnóstico por imagem
7.
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
8.
PLoS One ; 15(7): e0235039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32707574

RESUMO

Functional brain network (FBN), estimated with functional magnetic resonance imaging (fMRI), has become a potentially useful way of diagnosing neurological disorders in their early stages by comparing the connectivity patterns between different brain regions across subjects. However, this depends, to a great extent, on the quality of the estimated FBNs, indicating that FBN estimation is a key step for the subsequent task of disorder identification. In the past decades, researchers have developed many methods to estimate FBNs, including Pearson's correlation and (regularized) partial correlation, etc. Despite their widespread applications in current studies, most of the existing methods estimate FBNs only based on the dependency between the measured blood oxygen level dependent (BOLD) signals, which ignores spatial relationship of signals associated with different brain regions. Due to the space and material parsimony principle of our brain, we believe that the spatial distance between brain regions has an important influence on FBN topology. Therefore, in this paper, we assume that spatially neighboring brain regions tend to have stronger connections and/or share similar connections with others; based on this assumption, we propose two novel methods to estimate FBNs by incorporating the information of brain region distance into the estimation model. To validate the effectiveness of the proposed methods, we use the estimated FBNs to identify subjects with mild cognitive impairment (MCI) from normal controls (NCs). Experimental results show that the proposed methods are better than the baseline methods in the sense of MCI identification accuracy.


Assuntos
Disfunção Cognitiva/diagnóstico , Conectoma/métodos , Imagem por Ressonância Magnética/métodos , Rede Nervosa , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Mapeamento Encefálico/métodos , Disfunção Cognitiva/diagnóstico por imagem , Feminino , Humanos , Masculino , Modelos Teóricos , Rede Nervosa/diagnóstico por imagem , Análise Espacial
9.
Neurology ; 95(11): e1528-e1537, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32641526

RESUMO

OBJECTIVE: The disconnectivity hypothesis postulates that partial loss of connecting white matter fibers between brain regions contributes to the development of dementia. Using diffusion MRI to quantify global and tract-specific white matter microstructural integrity, we tested this hypothesis in a longitudinal population-based study. METHODS: Global and tract-specific fractional anisotropy (FA) and mean diffusivity (MD) were obtained in 4,415 people without dementia (mean age 63.9 years, 55.0% women) from the prospective population-based Rotterdam Study with brain MRI between 2005 and 2011. We modeled the association of these diffusion measures with risk of dementia (follow-up until 2016) and with changes on repeated cognitive assessment after on average 5.4 years, adjusting for age, sex, education, macrostructural MRI markers, depressive symptoms, cardiovascular risk factors, and APOE genotype. RESULTS: During a median follow-up of 6.8 years, 101 participants had incident dementia, of whom 83 had clinical Alzheimer disease (AD). Lower global values of FA and higher values of MD were associated with an increased risk of dementia (adjusted hazard ratio [95% confidence interval (CI)] per SD increase for MD 1.79 [1.44-2.23] and FA 0.65 [0.52-0.80]). Similarly, lower global values of FA and higher values of MD related to more cognitive decline in people without dementia (difference in global cognition per SD increase in MD [95% CI] was -0.04 [-0.07 to -0.01]). Associations were most profound in the projection, association, and limbic system tracts. CONCLUSIONS: Structural disconnectivity is associated with an increased risk of dementia and more pronounced cognitive decline in the general population.


Assuntos
Encéfalo/diagnóstico por imagem , Demência/diagnóstico por imagem , Demência/epidemiologia , Rede Nervosa/diagnóstico por imagem , Vigilância da População , Idoso , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética/tendências , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Vigilância da População/métodos , Fatores de Risco
11.
J Headache Pain ; 21(1): 92, 2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32682393

RESUMO

BACKGROUND: We investigated intracerebral fiber bundles using a tract-based spatial statistics (TBSS) analysis of diffusion tensor imaging (DTI) data to verify microstructural integrity in patients with episodic (MO) and chronic migraine (CM). METHODS: We performed DTI in 19 patients with MO within interictal periods, 18 patients with CM without any history of drug abuse, and 18 healthy controls (HCs) using a 3 T magnetic resonance imaging scanner. We calculated diffusion metrics, including fractional anisotropy (FA), axial diffusion (AD), radial diffusion (RD), and mean diffusion (MD). RESULTS: TBSS revealed no significant differences in the FA, MD, RD, and AD maps between the MO and HC groups. In comparison to the HC group, the CM group exhibited widespread increased RD (bilateral superior [SCR] and posterior corona radiata [PCR], bilateral genu of the corpus callosum [CC], bilateral posterior limb of internal capsule [IC], bilateral superior longitudinal fasciculus [LF]) and MD values (tracts of the right SCR and PCR, right superior LF, and right splenium of the CC). In comparison to the MO group, the CM group showed decreased FA (bilateral SCR and PCR, bilateral body of CC, right superior LF, right forceps minor) and increased MD values (bilateral SCR and right PCR, right body of CC, right superior LF, right splenium of CC, and right posterior limb of IC). CONCLUSION: Our results suggest that chronic migraine can be associated with the widespread disruption of normal white matter integrity in the brain.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Transtornos de Enxaqueca/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Uso Excessivo de Medicamentos Prescritos , Substância Branca/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/epidemiologia , Estudos Prospectivos
12.
J Headache Pain ; 21(1): 93, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32723299

RESUMO

BACKGROUND: Post-traumatic headache (PTH) is one of the most frequent symptoms following mild traumatic brain injury (mTBI). Neuroimaging studies implicate hypothalamic function connectivity (FC) disruption as an important factor in pain disorders. However, it is unknown whether there are alterations in the hypothalamus-based resting state FC within PTH following mTBI at the acute stage and its relationship with headache symptom measurement. METHODS: Forty-four mTBI patients with PTH, 27 mTBI patients without PTH and 43 healthy controls who were well matched for age, gender, and years of education were enrolled in this study. All participants underwent resting-state functional magnetic resonance imaging (fMRI) scanning as well as headache symptom measurement and cognitive assessment. Hypothalamic resting state networks were characterized by using a standard seed-based whole-brain correlation method. The bilateral hypothalamic FC was compared among the three groups. Furthermore, the correlations between hypothalamic resting state networks and headache frequency, headache intensity and MoCA scores was investigated in mTBI patients with PTH using Pearson rank correlation. RESULTS: Compared with mTBI patients without PTH, mTBI patients with PTH at the acute stage presented significantly decreased left hypothalamus-based FC with the right middle frontal gyrus (MFG) and right medial superior frontal gyrus (mSFG), and significantly decreased right hypothalamus-based FC with the right MFG. Decreased FC of the right MFG was significantly positively associated with headache frequency and headache intensity (r = 0.339, p = 0.024; r = 0.408, p = 0.006, respectively). Decreased FC of the right mSFG was significantly positively associated with headache frequency and headache intensity (r = 0.740, p < 0.0001; r = 0.655, p < 0.0001, respectively). CONCLUSION: Our data provided evidence of disrupted hypothalamic FC in patients with acute mTBI with PTH, while abnormal FC significantly correlated with headache symptom measurement. Taken together, these changes may play an essential role in the neuropathological mechanism of mTBI patients with PTH.


Assuntos
Concussão Encefálica/diagnóstico por imagem , Hipotálamo/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Cefaleia Pós-Traumática/diagnóstico por imagem , Adulto , Concussão Encefálica/epidemiologia , Concussão Encefálica/fisiopatologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Hipotálamo/fisiopatologia , Imagem por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/tendências , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Cefaleia Pós-Traumática/epidemiologia , Cefaleia Pós-Traumática/fisiopatologia , Estudos Prospectivos
13.
Neurology ; 95(6): e637-e642, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32636329

RESUMO

OBJECTIVE: To study neural networks involved in hyperkinetic seizures (HKS) using ictal SPECT. METHODS: We retrospectively identified 18 patients with HKS evaluated at the Cleveland Clinic between 2005 and 2015 with video-EEG monitoring and ictal SPECT. Semiology was confirmed by the consensus of 2 epileptologists' independent reviews and classified as type 1, 2, or 3 HKS. SPECT data were analyzed by 2 independent physicians using a z score of 1.5. Ictal hyperperfusion patterns for each group were analyzed visually and with SPM. Spatial normalization to Montreal Neurological Institute space for each patient's data was performed, followed by flipping of data from patients with left-sided ictal onset to the right side. Finally, an average z score map for each group was calculated. RESULTS: Visual analysis and SPM identified different patterns of ictal hyperperfusion in the 3 subtypes of HKS. Type 1 seizures showed hyperperfusion in a more anteriorly located network involving the anterior insula, orbitofrontal cortex, cingulate, and anterior perisylvian region and rostral midbrain. Type 2 seizures were associated with hyperperfusion in a more caudally located network involving the orbitofrontal cortex, cingulate (middle and posterior), basal ganglia, thalami, and cerebellum. Type 3 seizures showed a mixed pattern of SPECT hyperperfusion involving the temporal pole and anterior perisylvian region. CONCLUSIONS: Each of the 3 different semiologic subtypes of HKS is associated with distinct patterns of hyperperfusion, providing further insight into the neural networks involved. This knowledge may inform placement of invasive EEG electrodes in patients with HKS semiology undergoing presurgical evaluation.


Assuntos
Epilepsia Motora Parcial/diagnóstico por imagem , Hipercinese/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Mapeamento Encefálico , Circulação Cerebrovascular , Criança , Dominância Cerebral , Eletroencefalografia/métodos , Epilepsia Motora Parcial/classificação , Epilepsia Motora Parcial/fisiopatologia , Feminino , Humanos , Hipercinese/fisiopatologia , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Cuidados Pré-Operatórios , Estudos Retrospectivos , Gravação em Vídeo/métodos , Adulto Jovem
14.
Nat Commun ; 11(1): 3002, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532982

RESUMO

Humans observe a wide range of actions in their surroundings. How is the visual cortex organized to process this diverse input? Using functional neuroimaging, we measured brain responses while participants viewed short videos of everyday actions, then probed the structure in these responses using voxel-wise encoding modeling. Responses are well fit by feature spaces that capture the body parts involved in an action and the action's targets (i.e. whether the action was directed at an object, another person, the actor, and space). Clustering analyses reveal five large-scale networks that summarize the voxel tuning: one related to social aspects of an action, and four related to the scale of the interaction envelope, ranging from fine-scale manipulations directed at objects, to large-scale whole-body movements directed at distant locations. We propose that these networks reveal the major representational joints in how actions are processed by visual regions of the brain.


Assuntos
Encéfalo/fisiologia , Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Córtex Visual/fisiologia , Adulto , Fenômenos Biomecânicos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Neuroimagem Funcional/métodos , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Estimulação Luminosa/métodos , Comportamento Social , Córtex Visual/diagnóstico por imagem , Adulto Jovem
15.
PLoS One ; 15(6): e0234382, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584824

RESUMO

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


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Rede Nervosa/fisiologia , Adaptação Fisiológica , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/terapia , Estudos de Casos e Controles , Conectoma , Óculos , Feminino , Lateralidade Funcional/fisiologia , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Dispositivos Ópticos , Transtornos da Percepção/diagnóstico por imagem , Transtornos da Percepção/fisiopatologia , Transtornos da Percepção/terapia , Adulto Jovem
16.
Obesity (Silver Spring) ; 28(7): 1283-1291, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32510870

RESUMO

OBJECTIVE: This study aimed to investigate regional neural activity and regulation of patterns in the reorganized neural network of obesity and explore the correlation between brain activities and eating behavior. METHODS: A total of 23 individuals with obesity and 23 controls with normal weight were enrolled. Functional magnetic resonance imaging (fMRI) data were acquired using 3.0-T MRI. Amplitude of low-frequency fluctuation and functional connectivity (FC) analyses were conducted using Data Processing Assistant for resting-state fMRI and Resting-State fMRI Data Analysis Toolkit (REST). RESULTS: The group with obesity showed increased amplitude of low-frequency values in left fusiform gyrus/amygdala, inferior temporal gyrus (ITG), hippocampus/parahippocampal gyrus, and bilateral caudate but decreased values in right superior temporal gyrus. The group with obesity showed increased FC between left caudate and right superior temporal gyrus, left fusiform gyrus/amygdala and left ITG, right caudate and left fusiform gyrus/amygdala, and right caudate and left hippocampus/parahippocampal gyrus. Dutch Eating Behavior Questionnaire-Emotional scores were positively correlated with FC between left hippocampus/parahippocampal gyrus and right caudate but negatively correlated with FC between left fusiform gyrus/amygdala and left ITG. CONCLUSIONS: The study indicated the reorganized neural network presented as a bilateral cross-regulation pattern across hemispheres between reward and various appetite-related functional processing, thus affecting emotional and external eating behavior. These results could provide further evidence for neuropsychological underpinnings of food intake and their neuromodulatory therapeutic potential in obesity.


Assuntos
Regulação do Apetite/fisiologia , Encéfalo/diagnóstico por imagem , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Obesidade/psicologia , Adolescente , Adulto , Encéfalo/patologia , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/fisiopatologia , Descanso/fisiologia , Descanso/psicologia , Adulto Jovem
17.
Proc Natl Acad Sci U S A ; 117(21): 11799-11810, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32385157

RESUMO

Decisions about when to act are critical for survival in humans as in animals, but how a desire is translated into the decision that an action is worth taking at any particular point in time is incompletely understood. Here we show that a simple model developed to explain when animals decide it is worth taking an action also explains a significant portion of the variance in timing observed when humans take voluntary actions. The model focuses on the current environment's potential for reward, the timing of the individual's own recent actions, and the outcomes of those actions. We show, by using ultrahigh-field MRI scanning, that in addition to anterior cingulate cortex within medial frontal cortex, a group of subcortical structures including striatum, substantia nigra, basal forebrain (BF), pedunculopontine nucleus (PPN), and habenula (HB) encode trial-by-trial variation in action time. Further analysis of the activity patterns found in each area together with psychophysiological interaction analysis and structural equation modeling suggested a model in which BF integrates contextual information that will influence the decision about when to act and communicates this information, in parallel with PPN and HB influences, to nigrostriatal circuits. It is then in the nigrostriatal circuit that action initiation per se begins.


Assuntos
Prosencéfalo Basal/fisiologia , Tomada de Decisões/fisiologia , Substância Negra/fisiologia , Adulto , Prosencéfalo Basal/diagnóstico por imagem , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Modelos Neurológicos , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Substância Negra/diagnóstico por imagem
18.
Nat Commun ; 11(1): 2612, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457389

RESUMO

Tau is a hallmark pathology of Alzheimer's disease, and animal models have suggested that tau spreads from cell to cell through neuronal connections, facilitated by ß-amyloid (Aß). We test this hypothesis in humans using an epidemic spreading model (ESM) to simulate tau spread, and compare these simulations to observed patterns measured using tau-PET in 312 individuals along Alzheimer's disease continuum. Up to 70% of the variance in the overall spatial pattern of tau can be explained by our model. Surprisingly, the ESM predicts the spatial patterns of tau irrespective of whether brain Aß is present, but regions with greater Aß burden show greater tau than predicted by connectivity patterns, suggesting a role of Aß in accelerating tau spread. Altogether, our results provide evidence in humans that tau spreads through neuronal communication pathways even in normal aging, and that this process is accelerated by the presence of brain Aß.


Assuntos
Doença de Alzheimer/metabolismo , Proteínas de Membrana/metabolismo , Rede Nervosa/metabolismo , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/fisiologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Conectoma , Feminino , Humanos , Masculino , Modelos Neurológicos , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Tomografia por Emissão de Pósitrons
19.
Nat Commun ; 11(1): 2534, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439858

RESUMO

Zika virus (ZIKV) infection has a profound impact on the fetal nervous system. The postnatal period is also a time of rapid brain growth, and it is important to understand the potential neurobehavioral consequences of ZIKV infection during infancy. Here we show that postnatal ZIKV infection in a rhesus macaque model resulted in long-term behavioral, motor, and cognitive changes, including increased emotional reactivity, decreased social contact, loss of balance, and deficits in visual recognition memory at one year of age. Structural and functional MRI showed that ZIKV-infected infant rhesus macaques had persistent enlargement of lateral ventricles, smaller volumes and altered functional connectivity between brain areas important for socioemotional behavior, cognitive, and motor function (e.g. amygdala, hippocampus, cerebellum). Neuropathological changes corresponded with neuroimaging results and were consistent with the behavioral and memory deficits. Overall, this study demonstrates that postnatal ZIKV infection in this model may have long-lasting neurodevelopmental consequences.


Assuntos
Encéfalo/patologia , Infecção por Zika virus/patologia , Infecção por Zika virus/psicologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Cognição/fisiologia , Modelos Animais de Doenças , Feminino , Macaca mulatta , Memória/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia , Neuroimagem , Comportamento Social , Zika virus/fisiologia , Infecção por Zika virus/diagnóstico por imagem , Infecção por Zika virus/fisiopatologia
20.
J Headache Pain ; 21(1): 47, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32375638

RESUMO

BACKGROUND: Migraine is a severe and disabling brain disorder, and the exact neurological mechanisms remain unclear. Migraineurs have altered pain perception, and headache attacks disrupt their sensory information processing and sensorimotor integration. The altered functional connectivity of sub-regions of sensorimotor brain areas with other brain cortex associated with migraine needs further investigation. METHODS: Forty-eight migraineurs without aura during the interictal phase and 48 age- and sex-matched healthy controls underwent resting-state functional magnetic resonance imaging scans. We utilized seed-based functional connectivity analysis to investigate whether patients exhibited abnormal functional connectivity between sub-regions of sensorimotor brain areas and cortex regions. RESULTS: We found that patients with migraineurs without aura exhibited disrupted functional connectivities between the sensorimotor areas and the visual cortex, temporal cortex, posterior parietal lobule, prefrontal areas, precuneus, cingulate gyrus, sensorimotor areas proper and cerebellum areas compared with healthy controls. In addition, the clinical data of the patients, such as disease duration, pain intensity and HIT-6 score, were negatively correlated with these impaired functional connectivities. CONCLUSION: In patients with migraineurs without aura, the functional connectivities between the sensorimotor brain areas and other brain regions was reduced. These disrupted functional connectivities might contribute to abnormalities in visual processing, multisensory integration, nociception processing, spatial attention and intention and dysfunction in cognitive evaluation and modulation of pain. Recurrent headache attacks might lead to the disrupted network between primary motor cortex and temporal regions and between primary somatosensory cortex and temporal regions. Pain sensitivity and patient quality of life are closely tied to the abnormal functional connectivity between sensorimotor regions and other brain areas.


Assuntos
Imagem por Ressonância Magnética/métodos , Enxaqueca sem Aura/diagnóstico por imagem , Córtex Motor/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Córtex Somatossensorial/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca sem Aura/fisiopatologia , Córtex Motor/fisiopatologia , Rede Nervosa/fisiopatologia , Dor/diagnóstico por imagem , Dor/fisiopatologia , Qualidade de Vida , Córtex Somatossensorial/fisiopatologia , Lobo Temporal/fisiopatologia , Adulto Jovem
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