1,102 research outputs found

    Visuospatial working memory facilitates indoor wayfinding and direction giving

    Get PDF
    The goal was to test the role of verbal and visuospatial working memory in wayfinding and direction giving in an indoor environment using a dual task paradigm. One hundred ninety-two participants were asked to find their way through one floor of a complex building and to provide directions for a fictitious recipient to find the way in one of three conditions: control (no secondary task), verbal dual task (word-nonword judgments as secondary task), or visuospatial dual task (clock hand judgments as secondary task). Wayfinding was slower in the visuospatial dual task condition than in the control condition, with the verbal condition intermediate. Directions were less accurate in the visuospatial dual task condition than in control and verbal conditions. Women provided more information in wayfinding directions than did men. Together, these findings indicate that visuospatial working memory plays an important role in wayfinding and direction giving in an indoor environment

    Specifying Links Between Executive Functioning and Theory of Mind during Middle Childhood: Cognitive Flexibility Predicts Social Understanding

    Get PDF
    The purpose of this study was to specify the development of and links between executive functioning and theory of mind during middle childhood. One hundred four 7- to 12-year-old children completed a battery of age-appropriate tasks measuring working memory, inhibition, flexibility, theory of mind, and vocabulary. As expected, spatial working memory and flexibility increased significantly with age, especially after 7 years. Moreover, flexibility predicted social understanding over and above the effects of age, vocabulary, working memory, and inhibition. Together, these findings highlight improvements in and tight relations between complex aspects of executive functioning and theory of mind during middle childhood and suggest that executive functioning and theory of mind are linked beyond their emergence in early childhood

    The impact of culture and recipient perspective on direction giving in the service of wayfinding

    Get PDF
    We examined how culture and recipient perspective affect direction giving during wayfinding. Participants from the United States and the Netherlands provided directions from starting locations to destinations for fictional recipients driving through a town (route perspective) or looking at a map of the town (survey perspective). US participants provided street names more frequently than did Dutch participants, whereas Dutch participants provided landmarks more frequently than did US participants. Moreover, US participants provided more cardinal descriptors when addressing listeners adopting a survey perspective relative to a route perspective but more landmarks and left-right descriptors when addressing listeners adopting a route perspective relative to a survey perspective. Participants from the Netherlands evinced a similar pattern with the important distinction that they mostly ignored cardinal terms, unless explicitly primed to do so and in a survey condition. In addition, this very low usage of cardinal terms seemed to be replaced by using more landmark descriptions. This study revealed remarkable flexibility in people's spatial descriptions but also stressed major differences in the use of spatial terms between US and Dutch participants

    Анализ систем оценки информационно коммуникационных компетенций

    Get PDF
    The article considers the methods of development of information-analytical system of formation of information-communicative competence of students through the portal of "Electronic University of information technology"

    Zeitbereichs-Modellreduktion und Sylvester-Gleichungen

    Get PDF

    Optimization-Based Parametric Model Order Reduction via H<sub>2</sub> ⊗ L<sub>2</sub> First-Order Necessary Conditions

    Get PDF

    Characteristic Potentials for Mesoscopic Rings Threaded by an Aharonov-Bohm Flux

    Full text link
    Electro-static potentials for samples with the topology of a ring and penetrated by an Aharonov-Bohm flux are discussed. The sensitivity of the electron-density distribution to small variations in the flux generates an effective electro-static potential which is itself a periodic function of flux. We investigate a simple model in which the flux sensitive potential leads to a persistent current which is enhanced compared to that of a loop of non-interacting electrons. For sample geometries with contacts the sensitivity of the electro-static potential to flux leads to a flux-induced capacitance. This capacitance gives the variation in charge due to an increment in flux. The flux-induced capacitance is contrasted with the electro-chemical capacitance which gives the variation in charge due to an increment in an electro-chemical potential. The discussion is formulated in terms of characteristic functions which give the variation of the electro-static potential in the interior of the conductor due to an increment in the external control parameters (flux, electro-chemical potentials). Paper submitted to the 16th Nordic Semiconductor Meeting, Laugarvatan, Iceland, June 12-15, 1994. The proceedings will be published in Physica Scripta.Comment: 23 pages + 4 figures, revtex, IBM-RC1955

    QTLs for the elongation of axile and lateral roots of maize in response to low water potential

    Get PDF
    Changes in root architecture and the maintenance of root growth in drying soil are key traits for the adaptation of maize (Zea mays L.) to drought environments. The goal of this study was to map quantitative trait loci (QTLs) for root growth and its response to dehydration in a population of 208 recombinant inbred lines from the International Maize and Wheat Improvement Center (CIMMYT). The parents, Ac7643 and Ac7729/TZSRW, are known to be drought-tolerant and drought-sensitive, respectively. Roots were grown in pouches under well-watered conditions or at low water potential induced by the osmolyte polyethylene glycol (PEG 8000). Axile root length (L Ax) increased linearly, while lateral root length (L Lat) increased exponentially over time. Thirteen QTLs were identified for six seedling traits: elongation rates of axile roots (ERAx), the rate constant of lateral root elongation (k Lat), the final respective lengths (L Ax and L Lat), and the ratios k Lat/ERAx and L Lat/L Ax. While QTLs for lateral root traits were constitutively expressed, most QTLs for axile root traits responded to water stress. For axile roots, common QTLs existed for ERAx and L Ax. Quantitative trait loci for the elongation rates of axile roots responded more clearly to water stress compared to root length. Two major QTLs were detected: a QTL for general vigor in bin 2.02, affecting most of the traits, and a QTL for the constitutive increase in k Lat and k Lat/ERAx in bins 6.04-6.05. The latter co-located with a major QTL for the anthesis-silking interval (ASI) reported in published field experiments, suggesting an involvement of root morphology in drought tolerance. Rapid seedling tests are feasible for elucidating the genetic response of root growth to low water potential. Some loci may even have pleiotropic effects on yield-related traits under drought stres

    Do quiescent arachnoid cysts alter CNS functional organization? An fMRI and morphometric study

    Get PDF
    OBJECTIVE: To investigate whether congenital and clinically quiescent arachnoid cysts (AC) in the left temporal fossa alter the functional organization of adjacent cortices. METHODS: fMRI mapping was applied in five right-handed asymptomatic patients to determine the functional organization of language. Moreover, morphometry was performed in each patient to gain the size of cortical surface areas and cortical thickness values in the neighboring brain adjacent to the AC and explicitly in the left opercular region. RESULTS: Four patients showed a clear left hemisphere language dominance regardless of the cyst size; a mixed laterality of language organization was found in the remaining patient. An interesting dissociation of morphometric data was assessed when comparing strongly language-related cortices in the inferior frontal gyrus with the entire neighboring cortices. Morphometry in the neighboring brain regions of the AC showed 1) overall reduced cortical surface areas and 2) a decrease in cortical thickness compared to the homologous right side. However, the surface area of the fronto-opercular region in the left inferior frontal gyrus-i.e., the pars triangularis and the pars opercularis-was larger on the left as compared to the right side. Both structures have earlier been identified to represent the morphologic substrate of language dominance in the left hemisphere. CONCLUSION: Arachnoid cysts do not disturb the normal asymmetry of hemisphere language organization despite delicate locations adjacent to the left inferior frontal gyrus