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1.
Brain Lang ; 237: 105231, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36716643

RESUMO

The present research used fMRI to longitudinally investigate the impact of learning new vocabulary on the activation pattern of the language control network by measuring BOLD signal changes during picture naming tasks with familiar pre-existing native words (old words) and new vocabulary. Nineteen healthy participants successfully learned new synonyms for already known Spanish words, and they performed a picture naming task using the old words and the new words immediately after learning and two weeks after learning. The results showed that naming with old words, compared to naming with newly learned words, produced activations in a cortical network involving frontal and parietal regions, whereas the opposite contrast showed activation in a broader cortical/subcortical network, including the SMA/ACC, the hippocampus, and the midbrain. These two networks are maintained two weeks after learning. These results suggest that the language control network can be separated into two functional circuits for diverse cognitive purposes.


Assuntos
Encéfalo , Vocabulário , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Idioma , Aprendizagem , Mapeamento Encefálico , Imageamento por Ressonância Magnética
2.
Eur J Health Econ ; 24(3): 335-347, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35616793

RESUMO

The European continent has one of the longest life expectancies in the world, but still faces a significant challenge to meet the health targets set by the Sustainable Development Goals of the United Nations for 2030. To improve the understanding of the rationale that guides health outcomes in Europe, this study assesses the direction and magnitude effects of the drivers that contribute to explain life expectancy at birth across 30 European countries for the period 2008-2018 at macro-level. For this purpose, an aggregated health production function is used allowing for spatial effects. The results indicate that an increase in the income level, health expenditure, trade openness, education attainment, or urbanisation might lead to an increase in life expectancy at birth, whereas calories intake or quantity of air pollutants have a negative impact on this health indicator. This implies that health policies should look beyond economic factors and focus also on social and environmental drivers. The results also indicate the existence of significant spillover effects, highlighting the need for coordinated European policies that account for the synergies between countries. Finally, a foresight analysis is conducted to obtain projections for 2030 under different socioeconomic pathways. Results reveal significant differences on longevity projections depending on the adoption, or not, of a more sustainable model of human development and provides valuable insight on the need for anticipatory planning measures to make longer life-spans compatible with the maintenance of the welfare state.


Assuntos
Expectativa de Vida , Longevidade , Recém-Nascido , Humanos , Escolaridade , Europa (Continente) , Países em Desenvolvimento , Fatores Socioeconômicos
3.
Front Hum Neurosci ; 16: 803163, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35652007

RESUMO

Using fMRI, we investigated how right temporal lobe gliomas affecting the posterior superior temporal sulcus alter neural processing observed during speech perception and production tasks. Behavioural language testing showed that three pre-operative neurosurgical patients with grade 2, grade 3 or grade 4 tumours had the same pattern of mild language impairment in the domains of object naming and written word comprehension. When matching heard words for semantic relatedness (a speech perception task), these patients showed under-activation in the tumour infiltrated right superior temporal lobe compared to 61 neurotypical participants and 16 patients with tumours that preserved the right postero-superior temporal lobe, with enhanced activation within the (tumour-free) contralateral left superior temporal lobe. In contrast, when correctly naming objects (a speech production task), the patients with right postero-superior temporal lobe tumours showed higher activation than both control groups in the same right postero-superior temporal lobe region that was under-activated during auditory semantic matching. The task dependent pattern of under-activation during the auditory speech task and over-activation during object naming was also observed in eight stroke patients with right hemisphere infarcts that affected the right postero-superior temporal lobe compared to eight stroke patients with right hemisphere infarcts that spared it. These task-specific and site-specific cross-pathology effects highlight the importance of the right temporal lobe for language processing and motivate further study of how right temporal lobe tumours affect language performance and neural reorganisation. These findings may have important implications for surgical management of these patients, as knowledge of the regions showing functional reorganisation may help to avoid their inadvertent damage during neurosurgery.

4.
Neuroimage ; 230: 117809, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33524579

RESUMO

Lysergic acid diethylamide (LSD) is a potent psychedelic drug, which has seen a revival in clinical and pharmacological research within recent years. Human neuroimaging studies have shown fundamental changes in brain-wide functional connectivity and an expansion of dynamical brain states, thus raising the question about a mechanistic explanation of the dynamics underlying these alterations. Here, we applied a novel perturbational approach based on a whole-brain computational model, which opens up the possibility to externally perturb different brain regions in silico and investigate differences in dynamical stability of different brain states, i.e. the dynamical response of a certain brain region to an external perturbation. After adjusting the whole-brain model parameters to reflect the dynamics of functional magnetic resonance imaging (fMRI) BOLD signals recorded under the influence of LSD or placebo, perturbations of different brain areas were simulated by either promoting or disrupting synchronization in the regarding brain region. After perturbation offset, we quantified the recovery characteristics of the brain area to its basal dynamical state with the Perturbational Integration Latency Index (PILI) and used this measure to distinguish between the two brain states. We found significant changes in dynamical complexity with consistently higher PILI values after LSD intake on a global level, which indicates a shift of the brain's global working point further away from a stable equilibrium as compared to normal conditions. On a local level, we found that the largest differences were measured within the limbic network, the visual network and the default mode network. Additionally, we found a higher variability of PILI values across different brain regions after LSD intake, indicating higher response diversity under LSD after an external perturbation. Our results provide important new insights into the brain-wide dynamical changes underlying the psychedelic state - here provoked by LSD intake - and underline possible future clinical applications of psychedelic drugs in particular psychiatric disorders.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Alucinógenos/administração & dosagem , Dietilamida do Ácido Lisérgico/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Modelos Neurológicos , Administração Intravenosa , Encéfalo/metabolismo , Simulação por Computador , Eletroencefalografia/métodos , Humanos , Magnetoencefalografia/métodos , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia
5.
Polymers (Basel) ; 12(8)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785165

RESUMO

We prepared high-performance aromatic copolyamides, containing bithiazole and thiazolo-thiazole groups in their main chain, from aromatic diamines and isophthaloyl chloride, to further improve the prominent thermal behavior and exceptional mechanical properties of commercial aramid fibers. The introduction of these groups leads to aramids with improved strength and moduli compared to commercial meta-oriented aromatic polyamides, together with an increase of their thermal performance. Moreover, their solubility, water uptake, and optical properties were evaluated in this work.

6.
J Clean Prod ; 254: 119832, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32362729

RESUMO

In October 2018, the European Union (EU) launched an updated bioeconomy strategy with the aim of encouraging the substitution of fossil carbon with biomass feedstock in the industry and in energy production while preserving ecosystem services. The objective of the paper is to analyse the links between the EU bioeconomy strategy and the Sustainable Development Goals (SDGs), and to assess what could be the main points of synergies and tensions between bioeconomy-related SDG targets. By semantically mapping the action plan of the 2018 EU bioeconomy strategy with the SDG targets, the paper finds that the bioeconomy strategy is aligned with 53 targets distributed in 12 of the 17 SDGs. Ex-post correlation analysis on bioeconomy-related SDGs indicators for 28 EU Member States (1990-2018) shows a predominance of synergies over trade-offs. More intense synergetic past developments (positive correlations) are found among clean energies (SDG 7), recycling (SDG 11), ecosystem preservation (SDG 15) and most of all other bioeconomy-related SDGs. Negative correlations are observed between agro-biodiversity (SDG 2), domestic material consumption of biomass (SDG 8 and 12), agriculture and industrial developments (SDG 2 and SDG 9) and a wide array of bioeconomy-related SDG indicators. The hotspots of strong correlations identified might be useful in further enrichment of ex-ante simulation models. From a policy coherence perspective, a wide range of policy instruments are already in place in the EU to foster synergies and may bring co-benefits. Policies oriented at preventing trade-offs are already in place but they have not overcome the antagonisms observed in this study yet. Change in practices, technical and technological innovations and the application of circular and 'cascading principles' are the most common fields of action.

7.
Front Syst Neurosci ; 13: 27, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354439

RESUMO

Over the past 2,500 years, contemplative traditions have explored the nature of the mind using meditation. More recently, neuroimaging research on meditation has revealed differences in brain function and structure in meditators. Nevertheless, the underlying neural mechanisms are still unclear. In order to understand how meditation shapes global activity through the brain, we investigated the spatiotemporal dynamics across the whole-brain functional network using the Intrinsic Ignition Framework. Recent neuroimaging studies have demonstrated that different states of consciousness differ in their underlying dynamical complexity, i.e., how the broadness of communication is elicited and distributed through the brain over time and space. In this work, controls and experienced meditators were scanned using functional magnetic resonance imaging (fMRI) during resting-state and meditation (focused attention on breathing). Our results evidenced that the dynamical complexity underlying meditation shows less complexity than during resting-state in the meditator group but not in the control group. Furthermore, we report that during resting-state, the brain activity of experienced meditators showed higher metastability (i.e., a wider dynamical regime over time) than the one observed in the control group. Overall, these results indicate that the meditation state operates in a different dynamical regime compared to the resting-state.

8.
Neuropsychologia ; 124: 246-253, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30521815

RESUMO

Our environment is full of statistical regularities, and we are attuned to learn about these regularities by employing Statistical Learning (SL), a domain-general ability that enables the implicit detection of probabilistic regularities in our surrounding environment. The role of brain connectivity on SL has been previously explored, highlighting the relevance of structural and functional connections between frontal, parietal, and temporal cortices. However, whether SL can induce changes in the functional connections of the resting state brain has yet to be investigated. To address this question, we applied a pre-post design where participants (n = 38) were submitted to resting-state fMRI acquisition before and after in-scanner exposure to either an artificial language stream (formed by 4 concatenated words) or a random audio stream. Our results showed that exposure to an artificial language stream significantly changed (corrected p < 0.05) the functional connectivity between Right Posterior Cingulum and Left Superior Parietal Lobule. This suggests that functional connectivity between brain networks supporting attentional and working memory processes may play an important role in statistical learning.


Assuntos
Encéfalo/fisiologia , Idioma , Aprendizagem/fisiologia , Percepção da Fala/fisiologia , Estimulação Acústica , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Estatística como Assunto , Adulto Jovem
9.
Neuroimage ; 178: 238-254, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29753842

RESUMO

The study of brain communication based on fMRI data is often limited because such measurements are a mixture of session-to-session variability with subject- and condition-related information. Disentangling these contributions is crucial for real-life applications, in particular when only a few recording sessions are available. The present study aims to define a reliable standard for the extraction of multiple signatures from fMRI data, while verifying that they do not mix information about the different modalities (e.g., subjects and conditions such as tasks performed by them). In particular, condition-specific signatures should not be contaminated by subject-related information, since they aim to generalize over subjects. Practically, signatures correspond to subnetworks of directed interactions between brain regions (typically 100 covering the whole brain) supporting the subject and condition identification for single fMRI sessions. The key for robust prediction is using effective connectivity instead of functional connectivity. Our method demonstrates excellent generalization capabilities for subject identification in two datasets, using only a few sessions per subject as reference. Using another dataset with resting state and movie viewing, we show that the two signatures related to subjects and tasks correspond to distinct subnetworks, which are thus topologically orthogonal. Our results set solid foundations for applications tailored to individual subjects, such as clinical diagnostic.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Conectoma/métodos , Processamento de Imagem Assistida por Computador/métodos , Individualidade , Imageamento por Ressonância Magnética/métodos , Modelos Teóricos , Adulto , Humanos , Descanso
10.
eNeuro ; 4(5)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28966977

RESUMO

A precise definition of a brain state has proven elusive. Here, we introduce the novel local-global concept of intrinsic ignition characterizing the dynamical complexity of different brain states. Naturally occurring intrinsic ignition events reflect the capability of a given brain area to propagate neuronal activity to other regions, giving rise to different levels of integration. The ignitory capability of brain regions is computed by the elicited level of integration for each intrinsic ignition event in each brain region, averaged over all events. This intrinsic ignition method is shown to clearly distinguish human neuroimaging data of two fundamental brain states (wakefulness and deep sleep). Importantly, whole-brain computational modelling of this data shows that at the optimal working point is found where there is maximal variability of the intrinsic ignition across brain regions. Thus, combining whole brain models with intrinsic ignition can provide novel insights into underlying mechanisms of brain states.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Sono/fisiologia , Vigília/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Simulação por Computador , Imagem de Tensor de Difusão , Eletroencefalografia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Modelos Neurológicos , Oxigênio/sangue , Adulto Jovem
11.
Neuroimage ; 159: 261-269, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28774649

RESUMO

According to Hickok and Poeppel (2007), the acquisition of new vocabulary rests on the dorsal language pathway connecting auditory and motor areas. The present study tested this hypothesis longitudinally by measuring BOLD signal changes during a verbal repetition task and modulation of resting state functional connectivity (rs-FC) in the dorsal stream. Thirty-five healthy participants, divided into trained and control groups, completed fMRI sessions on days 1, 10, and 24. Between days 1 and 10, the trained group learned 84 new pseudowords associated with 84 native words. Task-related fMRI results showed a reduced activity in the IFG and STG while processing the learned vocabulary after training, returning to initial values two weeks later. Moreover, rs-fMRI analysis showed stronger rs-FC between the IFG and STG in the trained group than in the control group after learning, especially on day 24. These neural changes were more evident in participants with a larger vocabulary. Discussion focuses on the prominent role of the dorsal stream in vocabulary acquisition. Even when their meaning was known, newly learned words were again processed through the dorsal stream two weeks after learning, with the increase in rs-FC between auditory and motor areas being a relevant long-term imprint of vocabulary learning.


Assuntos
Encéfalo/fisiologia , Vias Neurais/fisiologia , Aprendizagem Verbal/fisiologia , Feminino , Humanos , Idioma , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Plasticidade Neuronal/fisiologia , Adulto Jovem
12.
J Org Chem ; 82(2): 1155-1165, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-27992220

RESUMO

A convenient method for the preparation of synthetically useful 3-iodoindene derivatives has been developed. This protocol, based on the 5-endo iodocyclization reaction of o-(alkynyl)styrenes, represents one of the scarce examples of halocyclizations using olefins as nucleophilic counterparts and allows the synthesis of both 3-iodo-1H-indenes (from ß-alkyl-ß-alkyl/aryl-o-(alkynyl)styrenes) and 3-iodobenzofulvenes (from ß,ß-diaryl-o-(alkynyl)styrenes) in good yields under mild reaction conditions. In addition, related alkoxyiodocyclization processes are described, which are particularly interesting in their intramolecular version because they allow the synthesis of heteropolycyclic structures containing the indene core. Finally, the usefulness of the prepared 3-iodoindenes has been demonstrated by the synthesis of several polysubstituted indene derivatives through conventional palladium-catalyzed cross-coupling reactions and iodine-lithium exchange processes.

13.
Org Lett ; 18(5): 1072-5, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26883951

RESUMO

Gold(I)-catalyzed cycloisomerization of ß,ß-diaryl-o-(alkynyl)styrenes at 80 °C selectively yields dihydroindeno[2,1-a]indenes in a transformation that encompasses a formal [4 + 1] cycloaddition and takes place through a cascade 5-endo-cyclization-diene activation-iso-Nazarov cyclization. In addition, by performing the reaction at 0 °C, the same substrates exclusively give rise to benzofulvene derivatives, which have also been shown to be intermediates in the formation of the tetracyclics.

14.
Neuroimage ; 125: 437-445, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26505300

RESUMO

Naturally acquiring a language shapes the human brain through a long-lasting learning and practice process. This is supported by previous studies showing that managing more than one language from early childhood has an impact on brain structure and function. However, to what extent bilingual individuals present neuroanatomical peculiarities at the subcortical level with respect to monolinguals is yet not well understood, despite the key role of subcortical gray matter for a number of language functions, including monitoring of speech production and language control - two processes especially solicited by bilinguals. Here we addressed this issue by performing a subcortical surface-based analysis in a sample of monolinguals and simultaneous bilinguals (N=88) that only differed in their language experience from birth. This analysis allowed us to study with great anatomical precision the potential differences in morphology of key subcortical structures, namely, the caudate, accumbens, putamen, globus pallidus and thalamus. Vertexwise analyses revealed significantly expanded subcortical structures for bilinguals compared to monolinguals, localized in bilateral putamen and thalamus, as well as in the left globus pallidus and right caudate nucleus. A topographical interpretation of our results suggests that a more complex phonological system in bilinguals may lead to a greater development of a subcortical brain network involved in monitoring articulatory processes.


Assuntos
Gânglios da Base/anatomia & histologia , Gânglios da Base/fisiologia , Multilinguismo , Tálamo/anatomia & histologia , Tálamo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
15.
Brain Lang ; 142: 36-44, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25658632

RESUMO

The present research used fMRI to measure brain activity in passive listening and picture-naming tasks with a group of early high proficient Spanish-Catalan bilinguals, in which Spanish was dominant, and a group of Spanish monolinguals. Both tasks were conducted in Spanish and the effect of cognateness was studied. The behavioural results showed slow naming responses in bilinguals. The fMRI results revealed that bilinguals and monolinguals differed only during the picture naming task. Unlike previous results, obtained mainly with L2, monolinguals displayed more activity in receptive language areas and less activity in the posterior cingulate cortex and right STG in the picture-naming task than bilinguals. As far as we know, this is the first study to investigate the neural basis of L1 processing in bilinguals and monolinguals by performing the task in the same language and in a monolingual context. The results indicate more efficient use of language networks in monolinguals because bilinguals utilised a more distributed network, which may imply subtle processing disadvantages.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Giro do Cíngulo/fisiologia , Imageamento por Ressonância Magnética , Multilinguismo , Comportamento Verbal/fisiologia , Adulto , Dominância Cerebral/fisiologia , Feminino , Humanos , Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Masculino , Rede Nervosa/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Percepção da Fala , Adulto Jovem
16.
Neuropsychologia ; 68: 51-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25556848

RESUMO

Prompt detection of unexpected changes in the sensory environment is critical for survival. In the auditory domain, the occurrence of a rare stimulus triggers a cascade of neurophysiological events spanning over multiple time-scales. Besides the role of the mismatch negativity (MMN), whose cortical generators are located in supratemporal areas, cumulative evidence suggests that violations of auditory regularities can be detected earlier and lower in the auditory hierarchy. Recent human scalp recordings have shown signatures of auditory mismatch responses at shorter latencies than those of the MMN. Moreover, animal single-unit recordings have demonstrated that rare stimulus changes cause a release from stimulus-specific adaptation in neurons of the primary auditory cortex, the medial geniculate body (MGB), and the inferior colliculus (IC). Although these data suggest that change detection is a pervasive property of the auditory system which may reside upstream cortical sites, direct evidence for the involvement of subcortical stages in the human auditory novelty system is lacking. Using event-related functional magnetic resonance imaging during a frequency oddball paradigm, we here report that auditory deviance detection occurs in the MGB and the IC of healthy human participants. By implementing a random condition controlling for neural refractoriness effects, we show that auditory change detection in these subcortical stations involves the encoding of statistical regularities from the acoustic input. These results provide the first direct evidence of the existence of multiple mismatch detectors nested at different levels along the human ascending auditory pathway.


Assuntos
Vias Auditivas/fisiologia , Percepção Auditiva/fisiologia , Corpos Geniculados/fisiologia , Colículos Inferiores/fisiologia , Mesencéfalo/fisiologia , Tálamo/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Detecção de Sinal Psicológico , Adulto Jovem
17.
Chemistry ; 21(7): 3042-52, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25557166

RESUMO

Indenes and related polycyclic structures have been efficiently synthesized by gold(I)-catalyzed cycloisomerizations of appropriate ortho-(alkynyl)styrenes. Disubstitution at the terminal position of the olefin was demonstrated to be essential to obtain products originating from a formal 5-endo-dig cyclization. Interestingly, a complete switch in the selectivity of the cyclization of o-(alkynyl)-α-methylstyrenes from 6-endo to 5-endo was observed by adding an alcohol to the reaction media. This allowed the synthesis of interesting indenes bearing an all-carbon quaternary center at C1. Moreover, dihydrobenzo[a]fluorenes can be obtained from substrates bearing a secondary alkyl group at the ß-position of the styrene moiety by a tandem cycloisomerization/1,2-hydride migration process. In addition, diverse polycyclic compounds were obtained by an intramolecular gold-catalyzed alkoxycyclization of o-(alkynyl)styrenes bearing a nucleophile in their structure. Finally, the use of a chiral gold complex allowed access to elusive chiral 1H-indenes in good enantioselectivities.

18.
Neuropsychologia ; 76: 153-62, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25496810

RESUMO

We used fMRI in 35 healthy participants to investigate how two neighbouring subregions in the lateral anterior temporal lobe (LATL) contribute to semantic matching and object naming. Four different levels of processing were considered: (A) recognition of the object concepts; (B) search for semantic associations related to object stimuli; (C) retrieval of semantic concepts of interest; and (D) retrieval of stimulus specific concepts as required for naming. During semantic association matching on picture stimuli or heard object names, we found that activation in both subregions was higher when the objects were semantically related (mug-kettle) than unrelated (car-teapot). This is consistent with both LATL subregions playing a role in (C), the successful retrieval of amodal semantic concepts. In addition, one subregion was more activated for object naming than matching semantically related objects, consistent with (D), the retrieval of a specific concept for naming. We discuss the implications of these novel findings for cognitive models of semantic processing and left anterior temporal lobe function.


Assuntos
Rememoração Mental/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Semântica , Lobo Temporal/fisiologia , Adulto , Mapeamento Encefálico , Formação de Conceito/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Psicológico/fisiologia
19.
Brain Lang ; 132: 43-51, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24735970

RESUMO

We tested the hypothesis that early bilinguals and monolinguals use different brain areas when performing nonlinguistic executive control tasks. For this, we explored brain activity of early bilinguals and monolinguals during a manual stop-signal paradigm. Behaviorally, bilinguals and monolinguals did not show significant differences in the task, which led us to compare brain activation that cannot be attributed to differences in performance. Analyses demonstrated that monolinguals activated the anterior cingulate cortex more than bilinguals when performing the stop-signal task. These results offer direct support for the notion that early bilingualism exerts an effect on neural circuitry responsible for executive control. Consistent with recent reports, we found that bilinguals used the anterior cingulate more efficiently than monolinguals to monitor nonlinguistic cognitive conflicts.


Assuntos
Encéfalo/fisiologia , Função Executiva/fisiologia , Multilinguismo , Mapeamento Encefálico , Feminino , Giro do Cíngulo/fisiologia , Humanos , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
20.
Beilstein J Org Chem ; 9: 2242-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24204437

RESUMO

The cyclization of o-(alkynyl)-3-(methylbut-2-enyl)benzenes, 1,6-enynes having a condensed aromatic ring at C3-C4 positions, has been studied under the catalysis of cationic gold(I) complexes. The selective 6-endo-dig mode of cyclization observed for the 7-substituted substrates in the presence of water or methanol giving rise to hydroxy(methoxy)-functionalized dihydronaphthalene derivatives is highly remarkable in the context of the observed reaction pathways for the cycloisomerizations of 1,6-enynes bearing a trisubstituted olefin.

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