54 research outputs found

    Broca’s area network in language function: a pooling-data connectivity study

    Get PDF
    Background and Objective. Modern neuroimaging developments have demonstrated that cognitive functions correlate with brain networks rather than specific areas. The purpose of this paper was to analyze the connectivity of Broca's area based on language tasks. Methods. A connectivity modeling study was performed by pooling data of Broca's activation in language tasks. Fifty-seven papers that included 883 subjects in 84 experiments were analyzed. Analysis of Likelihood Estimates of pooled data was utilized to generate the map; thresholds at p < 0.01 were corrected for multiple comparisons and false discovery rate. Resulting images were co-registered into MNI standard space. Results. A network consisting of 16 clusters of activation was obtained. Main clusters were located in the frontal operculum, left posterior temporal region, supplementary motor area, and the parietal lobe. Less common clusters were seen in the sub-cortical structures including the left thalamus, left putamen, secondary visual areas and the right cerebellum. Conclusions. BA44-related networks involved in language processing were demonstrated utilizing a pooling-data connectivity study. Significance, interpretation and limitations of the results are discussed

    Broca\u27s area network in language function: a pooling-data connectivity study

    Get PDF
    BACKGROUND AND OBJECTIVE: Modern neuroimaging developments have demonstrated that cognitive functions correlate with brain networks rather than specific areas. The purpose of this paper was to analyze the connectivity of Broca\u27s area based on language tasks. METHODS: A connectivity modeling study was performed by pooling data of Broca\u27s activation in language tasks. Fifty-seven papers that included 883 subjects in 84 experiments were analyzed. Analysis of Likelihood Estimates of pooled data was utilized to generate the map; thresholds at p \u3c 0.01 were corrected for multiple comparisons and false discovery rate. Resulting images were co-registered into MNI standard space. RESULTS: A network consisting of 16 clusters of activation was obtained. Main clusters were located in the frontal operculum, left posterior temporal region, supplementary motor area, and the parietal lobe. Less common clusters were seen in the sub-cortical structures including the left thalamus, left putamen, secondary visual areas, and the right cerebellum. CONCLUSION: Broca\u27s area-44-related networks involved in language processing were demonstrated utilizing a pooling-data connectivity study. Significance, interpretation, and limitations of the results are discussed

    The Elusive Role of the Left Temporal Pole (BA38) in Language: A Preliminary Meta-Analytic Connectivity Study

    Get PDF
    It has been suggested that the left temporal pole (Brodmann area 38 (BA38)) participates in diverse language functions, including semantic processing, speech comprehension, and naming. Utilizing the activation likelihood estimation (ALE), a meta-analytic connectivity study was conducted to further our understanding on the role of BA38 in language. Departing from the BrainMap functional database, 11 papers corresponding to 12 paradigms including 201 participants were selected. Initially, � \u3c 0.01 was employed as the significance level, resulting in the presence of four different activation clusters.However,when the significance level was lowered to � \u3c 0.05, sixteen activation clusters appeared, including classical language areas such as Broca’s and Wernicke’s areas. It was concluded that (1) this meta-analytic connectivity study suggests the presence of two major connection circuits involving BA38; one is related to language,while the othermay be involved in visuospatial and integrative audiovisual functions. Furthermore, (2) BA38 also contributes to various brain networks supporting linguistic processes related not only to language comprehension but also to language production

    The language connectome : new pathways, new concepts

    Get PDF
    The field of the neurobiology of language is experiencing a paradigm shift in which the predominant Broca-Wernicke-Geschwind language model is being revised in favor of models that acknowledge that language is processed within a distributed cortical and subcortical system. While it is important to identify the brain regions that are part of this system, it is equally important to establish the anatomical connectivity supporting their functional interactions. The most promising framework moving forward is one in which language is processed via two interacting "streams"-a dorsal and ventral stream-anchored by long association fiber pathways, namely the superior longitudinal fasciculus/arcuate fasciculus, uncinate fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, and two less well-established pathways, the middle longitudinal fasciculus and extreme capsule. In this article, we review the most up-to-date literature on the anatomical connectivity and function of these pathways. We also review and emphasize the importance of the often overlooked cortico-subcortical connectivity for speech via the "motor stream" and associated fiber systems, including a recently identified cortical association tract, the frontal aslant tract. These pathways anchor the distributed cortical and subcortical systems that implement speech and language in the human brain

    Fiber tracking of the frontal aslant tract and subcomponents of the arcuate fasciculus in 5–8-year-olds : relation to speech and language function

    Get PDF
    Long association cortical fiber pathways support developing networks for speech and language, but we do not have a clear understanding of how they develop in early childhood. Using diffusion-weighted imaging (DWI) we tracked the frontal aslant tract (FAT), arcuate fasciculus (AF), and AF segments (anterior, long, posterior) in 19 typical 5–8-year-olds, an age range in which significant improvement in speech and language function occurs. While the microstructural properties of the FAT and the right AF did not show age-related differences over the age range we investigated, the left AF evidenced increasing fractional anisotropy with age. Microstructural properties of the AF in both hemispheres, however, predicted receptive and expressive language. Length of the left FAT also predicted receptive language, which provides initial suggestion that this pathway is important for language development. These findings have implications for models of language development and for models of the neurobiology of language more broadly

    Long Range Order at Low Temperature in Dipolar Spin Ice

    Full text link
    Recently it has been suggested that long range magnetic dipolar interactions are responsible for spin ice behavior in the Ising pyrochlore magnets Dy2Ti2O7{\rm Dy_{2}Ti_{2}O_{7}} and Ho2Ti2O7{\rm Ho_{2}Ti_{2}O_{7}}. We report here numerical results on the low temperature properties of the dipolar spin ice model, obtained via a new loop algorithm which greatly improves the dynamics at low temperature. We recover the previously reported missing entropy in this model, and find a first order transition to a long range ordered phase with zero total magnetization at very low temperature. We discuss the relevance of these results to Dy2Ti2O7{\rm Dy_{2}Ti_{2}O_{7}} and Ho2Ti2O7{\rm Ho_{2}Ti_{2}O_{7}}.Comment: New version of the manuscript. Now contains 3 POSTSCRIPT figures as opposed to 2 figures. Manuscript contains a more detailed discussion of the (i) nature of long-range ordered ground state, (ii) finite-size scaling results of the 1st order transition into the ground state. Order of authors has been changed. Resubmitted to Physical Review Letters Contact: [email protected]

    Caracterización Ecológica De Bofedales, Hábitat De Vicuñas Aplicando Metodologías De Teledeteccion Y Sig Estudio De Caso: Reserva De Producción De Fauna Chimborazo

    Get PDF
    This article presents a methodology based on classification of images from Landsat 7 ETM + to classify Andean wetlands known as ¨Bofedal¨ (wetland) located in the Fauna Production Reserve Chimborazo. Five of the seven in-situ geo-referenced bofedales belong to this category and two belong to the altiplano. These georeferenced reservoirs are the principal habitat of the vicuñas that are located within the RPFCH in the jurisdictions of the province of Tungurahua: Río Blanco, ¨Mocha¨ Valley area, 472.26 ha, 4400 m.; Chimborazo Province: Bofedal Quebrada Toni, Urbina area, 16.74 ha, 4301 m, bofedal El Refugio (Hermanos Carrel) at the Nevado Chimborazo, 1.44 ha, 4800msnm, and Curi bofedal Pogyo, Chorrera Mirador, 0.34 ha., 4523 m. and in the Bolivar Province: the wetlands Chag Pogyo, Pulinguí San Pablo, 19.36 ha, 4064 meters above sea level. Bofedal Sinche1, the sector ¨antennas¨, 8.53 ha. 4167 m., And Sinche2, ¨Puente Ayora¨ area, 9.39 ha., 3981 meters, the latter being Chag Pogyo highland bofedales. The seven bofedales represent 0.93% (527.87 ha) of the total area of the RPFCH (56653, 27 ha.). Two images of the satellite Landsat 7 ETM +, from the years 2001 - EarthSat, 2004 - USGS and an orthophoto 2013-2014 - GIS land were used. Georeferenced and rectified to capture the spatial and temporal variability of these ecosystems and define the characterization of bofedales in the reserve. For each image two classification methods were used, the supervised classification being the most efficient when representing the four representative classes in the RPFCH: snow, rock, pajonal and bofedal. Since this classification is oriented to objects that takes into account aspects such as shape and texture and not just the spectral information of each pixel. Allowing to obtain information on the characteristics and spatial distribution of the bofedales which was verified and validated later in the field. This process allows the generation of digital cartography with the identification, delimited and distributed bofedales along the RPFCH, representing a total of approximately 1483.94 ha in the RPFCH. In addition, the Normalized Difference Vegetation Index (NDVI) was applied, which made it possible to differentiate water bodies from other coverages, as well as specifically to know the extent of the reservoirs present in the Reserve, in order to better infer Distribution of vicuñas

    INNOVA Research Journal

    Get PDF
    El (Censos, 2016) (INEC), en su encuesta nacional de empleo, desempleo y subempleo en el Ecuador, de marzo de 2016, informó que el 68,6% de las personas en edad de trabajar se considera económicamente activo; de éstos, el 94,3% se consideran con empleo, el 5,7% no cuenta con empleo formal o independiente. De las personas en edad de trabajar 31,4% forman parte de la población económicamente inactiva. El emprendimiento se presenta como una solución que permite generar empleo. A la luz de nuevas investigaciones sobre el consumo de carnes y productos procesados. Está evolucionando las percepciones de la población y se están modificando sus hábitos. Se cuestionan más sobre los efectos en su salud y sobre el impacto ambiental, es mayor la demanda de productos en cuya elaboración se genere un menor nivel de impacto ambiental. Siendo la responsabilidad ambiental, un factor que a las empresas competitivas globales y locales las ha llevado no sólo a cumplir con las disposiciones legales, sino a crear ventajas competitivas a partir de la promoción del trabajo realizado en favor de la protección del medio ambiente. El fomento de emprendimientos con responsabilidad ambiental, mediante el uso de fibras sintéticas y pieles artificiales ayudará a generar herramientas para incrementar el empleo, generando valor con responsabilidad ambiental
    corecore