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1.
Neurosci Biobehav Rev ; 129: 245-260, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34310977

RESUMO

Interacting with our environment requires the selection of appropriate responses and the inhibition of others. Such effortful inhibition is achieved by a number of interference resolution and global inhibition processes. This meta-analysis including 57 studies and 73 contrasts revisits the overlap and differences in brain areas supporting interference resolution and global inhibition in cortical and subcortical brain areas. Activation likelihood estimation was used to discern the brain regions subserving each type of cognitive control. Individual contrast analysis revealed a common activation of the bilateral insula and supplementary motor areas. Subtraction analyses demonstrated the voxel-wise differences in recruitment in a number of areas including the precuneus in the interference tasks and the frontal pole and dorsal striatum in the inhibition tasks. Our results display a surprising lack of subcortical involvement within these types of cognitive control, a finding that is likely to reflect a systematic gap in the field of functional neuroimaging.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Neuroimagem Funcional , Humanos , Inibição Psicológica , Funções Verossimilhança
2.
Brain Topogr ; 31(4): 513-545, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29497874

RESUMO

With the recent increased availability of ultra-high field (UHF) magnetic resonance imaging (MRI), substantial progress has been made in visualizing the human brain, which can now be done in extraordinary detail. This review provides an extensive overview of the use of UHF MRI in visualizing the human subcortex for both healthy and patient populations. The high inter-subject variability in size and location of subcortical structures limits the usability of atlases in the midbrain. Fortunately, the combined results of this review indicate that a large number of subcortical areas can be visualized in individual space using UHF MRI. Current limitations and potential solutions of UHF MRI for visualizing the subcortex are also discussed.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Humanos
3.
Brain Struct Funct ; 222(6): 2487-2505, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28168364

RESUMO

The aging brain undergoes several anatomical changes that can be measured with Magnetic Resonance Imaging (MRI). Early studies using lower field strengths have assessed changes in tissue properties mainly qualitatively, using [Formula: see text]- or [Formula: see text]- weighted images to provide image contrast. With the development of higher field strengths (7 T and above) and more advanced MRI contrasts, quantitative measures can be acquired even of small subcortical structures. This study investigates volumetric, spatial, and quantitative MRI parameter changes associated with healthy aging in a range of subcortical nuclei, including the basal ganglia, red nucleus, and the periaqueductal grey. The results show that aging has a heterogenous effects across regions. Across the subcortical areas an increase of [Formula: see text] values is observed, most likely indicating a loss of myelin. Only for a number of areas, a decrease of [Formula: see text] and increase of QSM is found, indicating an increase of iron. Aging also results in a location shift for a number of structures indicating the need for visualization of the anatomy of individual brains.


Assuntos
Envelhecimento , Encéfalo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Fatores Etários , Envelhecimento/metabolismo , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/metabolismo , Encéfalo/metabolismo , Estudos Transversais , Feminino , Humanos , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Substância Cinzenta Periaquedutal/diagnóstico por imagem , Substância Cinzenta Periaquedutal/metabolismo , Valor Preditivo dos Testes , Núcleo Rubro/diagnóstico por imagem , Núcleo Rubro/metabolismo , Reprodutibilidade dos Testes , Substância Negra/diagnóstico por imagem , Substância Negra/metabolismo , Núcleo Subtalâmico/diagnóstico por imagem , Núcleo Subtalâmico/metabolismo , Adulto Jovem
4.
Psychophysiology ; 54(1): 24-33, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28000260

RESUMO

Recent efforts to replicate structural brain-behavior correlations have called into question the replicability of structural brain measures used in cognitive neuroscience. Here, we report an evaluation of test-retest reliability of diffusion tensor imaging (DTI) measures, including fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity, in several white matter tracts previously shown to be involved in cognitive control. In a data set consisting of 34 healthy participants scanned twice on a single day, we observe overall stability of DTI measures. This stability remained in a subset of participants who were also scanned a third time on the same day as well as in a 2-week follow-up session. We conclude that DTI measures in these tracts show relative stability, and that alternative explanations for the recent failures of replication must be considered.


Assuntos
Encéfalo/anatomia & histologia , Imagem de Tensor de Difusão/métodos , Função Executiva/fisiologia , Substância Branca/anatomia & histologia , Adulto , Teorema de Bayes , Feminino , Humanos , Masculino , Tempo de Reação , Reprodutibilidade dos Testes , Adulto Jovem
5.
Environ Int ; 87: 66-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26641521

RESUMO

BACKGROUND: Particulate matter (PM) air pollution is a human lung carcinogen; however, the components responsible have not been identified. We assessed the associations between PM components and lung cancer incidence. METHODS: We used data from 14 cohort studies in eight European countries. We geocoded baseline addresses and assessed air pollution with land-use regression models for eight elements (Cu, Fe, K, Ni, S, Si, V and Zn) in size fractions of PM2.5 and PM10. We used Cox regression models with adjustment for potential confounders for cohort-specific analyses and random effect models for meta-analysis. RESULTS: The 245,782 cohort members contributed 3,229,220 person-years at risk. During follow-up (mean, 13.1 years), 1878 incident cases of lung cancer were diagnosed. In the meta-analyses, elevated hazard ratios (HRs) for lung cancer were associated with all elements except V; none was statistically significant. In analyses restricted to participants who did not change residence during follow-up, statistically significant associations were found for PM2.5 Cu (HR, 1.25; 95% CI, 1.01-1.53 per 5 ng/m(3)), PM10 Zn (1.28; 1.02-1.59 per 20 ng/m(3)), PM10 S (1.58; 1.03-2.44 per 200 ng/m(3)), PM10 Ni (1.59; 1.12-2.26 per 2 ng/m(3)) and PM10 K (1.17; 1.02-1.33 per 100 ng/m(3)). In two-pollutant models, associations between PM10 and PM2.5 and lung cancer were largely explained by PM2.5 S. CONCLUSIONS: This study indicates that the association between PM in air pollution and lung cancer can be attributed to various PM components and sources. PM containing S and Ni might be particularly important.


Assuntos
Poluentes Atmosféricos/análise , Exposição Ambiental/análise , Exposição por Inalação/análise , Neoplasias Pulmonares/epidemiologia , Material Particulado/análise , Adulto , Idoso , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Modelos de Riscos Proporcionais , Estudos Prospectivos , Risco
6.
Environ Int ; 85: 111-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26386464

RESUMO

BACKGROUND: Local strategies to reduce green-house gases (GHG) imply changes of non-climatic exposure patterns. OBJECTIVE: To assess the health impacts of locally relevant transport-related climate change policies in Basel, Switzerland. METHODS: We modelled change in mortality and morbidity for the year 2020 based on several locally relevant transport scenarios including all decided transport policies up to 2020, additional realistic and hypothesized traffic reductions, as well as ambitious diffusion levels of electric cars. The scenarios were compared to the reference condition in 2010 assumed as status quo. The changes in non-climatic population exposure included ambient air pollution, physical activity, and noise. As secondary outcome, changes in Disability-Adjusted Life Years (DALYs) were put into perspective with predicted changes of CO2 emissions and fuel consumption. RESULTS: Under the scenario that assumed a strict particle emissions standard in diesel cars and all planned transport measures, 3% of premature deaths could be prevented from projected PM2.5 exposure reduction. A traffic reduction scenario assuming more active trips provided only minor added health benefits for any of the changes in exposure considered. A hypothetical strong support to electric vehicles diffusion would have the largest health effectiveness given that the energy production in Basel comes from renewable sources. CONCLUSION: The planned local transport related GHG emission reduction policies in Basel are sensible for mitigating climate change and improving public health. In this context, the most effective policy remains increasing zero-emission vehicles.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Mudança Climática , Efeito Estufa/prevenção & controle , Avaliação do Impacto na Saúde/métodos , Emissões de Veículos/análise , Poluição do Ar/análise , Automóveis , Feminino , Humanos , Masculino , Modelos Teóricos , Suíça
7.
Neuroimage ; 94: 40-46, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24650599

RESUMO

Functional magnetic resonance imaging (MRI) data are usually registered into standard anatomical space. However, standard atlases, such as LPBA40, the Harvard-Oxford atlas, FreeSurfer, and the Jülich cytoarchitectonic maps all lack important detailed information about small subcortical structures like the substantia nigra and subthalamic nucleus. Here we introduce a new subcortical probabilistic atlas based on ultra-high resolution in-vivo anatomical imaging from 7 T MRI. The atlas includes six important but elusive subcortical nuclei: the striatum, the globus pallidus internal and external segment (GPi/e), the subthalamic nucleus, the substantia nigra, and the red nucleus. With a sample of 30 young subjects and carefully cross-validated delineation protocols, our atlas is able to capture the anatomical variability within healthy populations for each of the included structures at an unprecedented level of detail. All the generated probabilistic atlases are registered to MNI standard space and are publicly available.


Assuntos
Encéfalo/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Armazenamento e Recuperação da Informação/métodos , Imageamento por Ressonância Magnética/métodos , Modelos Anatômicos , Modelos Estatísticos , Simulação por Computador , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Modelos Biológicos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
8.
Brain Res ; 1383: 196-205, 2011 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-21281612

RESUMO

Perceiving and interpreting social information richness is something that humans do automatically whenever they engage in social interactions. Numerous studies have identified neural substrates, including mirror neurons that may enable such social perception. In this study, we temporarily disrupted activity in the left inferior frontal gyrus (LIFG) using repetitive transcranial magnetic stimulation (rTMS). We investigated whether this cortical region, that is hypothesized to include mirror neurons, plays a central role in social perception. The LIFG was stimulated in the experimental condition (n=18), the vertex was targeted in the control condition (n=19). Disrupting LIFG, but not vertex, increased reaction times during an emotion recognition task, and eliminated the suppression of the 8-12Hz EEG µ rhythm, postulated as an index of mirroring activity. The results of this study provide further evidence for the role of the human mirror neuron system (MNS) in social perception, and indicate that the MNS can be measured with EEG.


Assuntos
Lobo Frontal/fisiologia , Percepção Social , Mapeamento Encefálico , Eletroencefalografia , Lateralidade Funcional/fisiologia , Humanos , Estimulação Magnética Transcraniana , Adulto Jovem
9.
Sci Total Environ ; 408(12): 2517-26, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20356617

RESUMO

A speed limit of 80 km/h with "strict enforcement" has been introduced in 2005 on zones of urban motorways in The Netherlands with the aim to improve air quality of NO(2) and PM(10) along these motorways. Strict enforcement means speed control by camera surveillance over the whole trajectory of 2-4 km combined with licence plate recognition and automatic fining in case of exceeding the speed limit. Traffic data measured in Rotterdam and Amsterdam at the zones without and with speed management showed that traffic dynamics have been significantly reduced as a result of speed management with strict enforcement. Reduction of traffic dynamics results in more free-flowing traffic with relatively less NO(x) and exhaust PM(10) emissions compared to congested traffic, i.e., stop-and-go traffic. The actual effect on NO(x) and PM(10) emissions at these speed management zones was studied in the cities Rotterdam and Amsterdam. The study was performed in two different ways: firstly by measurements and by modelling the contribution to NO(x) and PM(10) concentrations on both sides of the motorways, and secondly by estimating the change in traffic dynamics and the effect on emissions. From the results of both approaches in this study, it was concluded that in our case study in the Netherlands emission reduction by speed management is in the range of 5-30% for NO(x) and 5-25% for PM(10). Actual emission reductions by speed management at a specific motorway mainly depend on the ratio of congested traffic prior and after implementation of speed management. The larger this ratio, the larger is the relative emission reduction. The impact on air quality of 80 km/h for NO(x) and PM(10) is largest on motorways with a high fraction of heavy-duty vehicles.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Óxidos de Nitrogênio/análise , Material Particulado/análise , Meios de Transporte/legislação & jurisprudência , Emissões de Veículos/análise , Cidades , Monitoramento Ambiental , Modelos Químicos , Países Baixos
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