oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Attentional influences on functional mapping of speech sounds in human auditory cortex
Jonas Obleser, Thomas Elbert, Carsten Eulitz
BMC Neuroscience , 2004, DOI: 10.1186/1471-2202-5-24
Abstract: During phonological categorization, a vowel-dependent difference of N100m source location perpendicular to the main tonotopic gradient replicated previous findings. In speaker categorization, the relative mapping of vowels remained unchanged but sources were shifted towards more posterior and more superior locations.These results imply that the N100m reflects the extraction of abstract invariants from the speech signal. This part of the processing is accomplished in auditory areas anterior to AI, which are part of the auditory 'what' system. This network seems to include spatially separable modules for identifying the phonological information and for associating it with a particular speaker that are activated in synchrony but within different regions, suggesting that the 'what' processing can be more adequately modeled by a stream of parallel stages. The relative activation of the parallel processing stages can be modulated by attentional or task demands.This study explores attentional modulation within the 'what'-stream of the auditory modality during phoneme processing. Knowledge of speech sound representation in the auditory domain is still sparse. However, parallels to the extensively studied visual modality and also to the somatosensory domain are becoming evident. For example, columnar mapping of several stimulus properties (as known from the visual cortex) has been revealed in human and animal research: acoustic parameters like spectral bandwidth, periodicity, stimulus intensity [1,2] or – for human speech sounds – distance between spectral peaks [3,4] appear to be mapped perpendicularly to the main cochleotopic gradient. Recently, a segregation of a ventral 'what' and a dorsal 'where' stream – as long established in the visual system [5] – has also been proposed for the auditory system. This conclusion was based on neuroanatomical and functional studies in macaques [6-8] and has been substantiated in humans [9,10].Given these parallels between sensory domain
Modeling the Adoption of Innovations in the Presence of Geographic and Media Influences  [PDF]
Jameson L. Toole,Meeyoung Cha,Marta C. González
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0029528
Abstract: While there is a large body of work examining the effects of social network structure on innovation adoption, models to date have lacked considerations of real geography or mass media. In this article, we show these features are crucial to making more accurate predictions of a social contagion and technology adoption at a city-to-city scale. Using data from the adoption of the popular micro-blogging platform, Twitter, we present a model of adoption on a network that places friendships in real geographic space and exposes individuals to mass media influence. We show that homophily both among individuals with similar propensities to adopt a technology and geographic location is critical to reproducing features of real spatiotemporal adoption. Furthermore, we estimate that mass media was responsible for increasing Twitter's user base two to four fold. To reflect this strength, we extend traditional contagion models to include an endogenous mass media agent that responds to those adopting an innovation as well as influencing agents to adopt themselves.
The Linguistic Characteristics of Virtual Geographic Environments
虚拟地理环境的地理学语言特征

LIN Hui,ZHU Qing,
林珲
,朱庆

遥感学报 , 2005,
Abstract: Language as the basic communication tool is one of the most significant functions of human beings. Geospatial information is the most important component of the human recognition of reality. From verbal and text language to map and GIS which is considered as the third generation of geographic languages, the evolution of geographic languages conveys the striking impact of information technology. The intrinsic obscure metaphor based information encoding and decoding tendency in lower dimensions of space misleads the communication between information and human. The innovation of information technology drives us to research and develop a further more powerful geographic language to maximize the information bandwidth from the environment to the brain, virtual geographic environments ( VGE ) as new generation of geographic languages is thus proposed. This paper discusses the linguistic characteristics of VGE vs. GIS or map in such several aspects as(1) the multi-dimensional (including dynamic) abstract representations of the real world. (2) the multi-modal visualizations with multi-viewpoint and multi-details, and analytical understanding. (3 ) the multiple natural interactions and geocollaboration across time, space and scale. (4) the multi-sensory spatial perceptual capability. VGE provides an integrated ideographic system and the capabilities of spatial information communication to facilitate user's perception of the geospace similar to the human's perception in the natural world, the information bandwidth from the real world to the human brain is then maximized. The authors therefore propose that VGE is the upmost geospatial information communication tools and human-computer interface, i. e. provides the augmentation of sensory reality, or succeeds GIS as the fourth generation of geographic languages from text to map and GIS, which is opening up new ways for us to comprehend the real world.
Rules from Words: A Dynamic Neural Basis for a Lawful Linguistic Process  [PDF]
David W. Gow, A. Conrad Nied
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0086212
Abstract: Listeners show a reliable bias towards interpreting speech sounds in a way that conforms to linguistic restrictions (phonotactic constraints) on the permissible patterning of speech sounds in a language. This perceptual bias may enforce and strengthen the systematicity that is the hallmark of phonological representation. Using Granger causality analysis of magnetic resonance imaging (MRI)- constrained magnetoencephalography (MEG) and electroencephalography (EEG) data, we tested the differential predictions of rule-based, frequency–based, and top-down lexical influence-driven explanations of processes that produce phonotactic biases in phoneme categorization. Consistent with the top-down lexical influence account, brain regions associated with the representation of words had a stronger influence on acoustic-phonetic regions in trials that led to the identification of phonotactically legal (versus illegal) word-initial consonant clusters. Regions associated with the application of linguistic rules had no such effect. Similarly, high frequency phoneme clusters failed to produce stronger feedforward influences by acoustic-phonetic regions on areas associated with higher linguistic representation. These results suggest that top-down lexical influences contribute to the systematicity of phonological representation.
Phenotypic Plasticity Influences the Size, Shape and Dynamics of the Geographic Distribution of an Invasive Plant  [PDF]
Jean-Baptiste Pichancourt, Rieks D. van Klinken
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0032323
Abstract: Phenotypic plasticity has long been suspected to allow invasive species to expand their geographic range across large-scale environmental gradients. We tested this possibility in Australia using a continental scale survey of the invasive tree Parkinsonia aculeata (Fabaceae) in twenty-three sites distributed across four climate regions and three habitat types. Using tree-level responses, we detected a trade-off between seed mass and seed number across the moisture gradient. Individual trees plastically and reversibly produced many small seeds at dry sites or years, and few big seeds at wet sites and years. Bigger seeds were positively correlated with higher seed and seedling survival rates. The trade-off, the relation between seed mass, seed and seedling survival, and other fitness components of the plant life-cycle were integrated within a matrix population model. The model confirms that the plastic response resulted in average fitness benefits across the life-cycle. Plasticity resulted in average fitness being positively maintained at the wet and dry range margins where extinction risks would otherwise have been high (“Jack-of-all-Trades” strategy JT), and fitness being maximized at the species range centre where extinction risks were already low (“Master-of-Some” strategy MS). The resulting hybrid “Jack-and-Master” strategy (JM) broadened the geographic range and amplified average fitness in the range centre. Our study provides the first empirical evidence for a JM species. It also confirms mechanistically the importance of phenotypic plasticity in determining the size, the shape and the dynamic of a species distribution. The JM allows rapid and reversible phenotypic responses to new or changing moisture conditions at different scales, providing the species with definite advantages over genetic adaptation when invading diverse and variable environments. Furthermore, natural selection pressure acting on phenotypic plasticity is predicted to result in maintenance of the JT and strengthening of the MS, further enhancing the species invasiveness in its range centre.
EFFECTS OF CROSS-LINGUISTIC INFLUENCES ON SECOND LANGUAGE ACQUISITION: A CORPUS-BASED STUDY OF SEMANTIC TRANSFER IN WRITTEN PRODUCTION
María del Mar Ramón Torrijos
Revista de Lingüística y Lenguas Aplicadas , 2009, DOI: 10.4995/rlyla.2009.741
Abstract: This article concentrates on the impact that cross-linguistic influences have on second language acquisition. It investigates the importance of the learner's native language (L1) in written production of a second language (L2), particularly the use of L1 linguistic rules by Spanish speakers when they are writing in the target language (L2). This exploratory research focuses on the production errors made by students relative to specific subsystems such as semantic and syntactic areas. Errors are studied with respect to the differences between Spanish and English through a contrastive analysis between both languages in problematic linguistic areas. In this article only semantic errors will be considered as a first approximation to the study of transfer in written production. The results indicate that transfer is a reality and an important determinant in the process of second language acquisition. Teachers in an EFL context should be able to identify this phenomenon in order to prevent the errors which may arise from it.
Geographic Variation in Osteoporotic Hip Fracture Incidence: The Growing Importance of Asian Influences in Coming Decades  [PDF]
D. K. Dhanwal,C. Cooper,E. M. Dennison
Journal of Osteoporosis , 2010, DOI: 10.4061/2010/757102
Abstract: Studies over the last few decades have demonstrated geographic variation in the incidence of hip fracture across continents and among different parts of the same region. This paper studies the epidemiology of hip fracture worldwide, with special emphasis on the geographic variation among Asian countries. Using the Pubmed database, keywords that were employed included hip fracture, incidence rate, geographic variation, osteoporosis, and epidemiology. Articles were chosen based on the basis of (1) focus: studies that were said to specifically focus on geographic variation in hip fracture from different continents with a focus on Asia; (2) language: studies that were in English; (3) methods: studies that used statistical tests to examine hip fracture incidence rates. The highest hip fracture rates are seen in Scandinavian countries and the US and the lowest in African countries. Fracture rates are intermediate in Asian populations. Among different ethnic populations, the highest fracture rates are seen in Caucasians and the lowest in blacks. There is also a north-south gradient, particularly in Europe, where more hip fractures occur in North Europe compared to the South.
Geographic Variation in Osteoporotic Hip Fracture Incidence: The Growing Importance of Asian Influences in Coming Decades  [PDF]
D. K. Dhanwal,C. Cooper,E. M. Dennison
Journal of Osteoporosis , 2010, DOI: 10.4061/2010/757102
Abstract: Studies over the last few decades have demonstrated geographic variation in the incidence of hip fracture across continents and among different parts of the same region. This paper studies the epidemiology of hip fracture worldwide, with special emphasis on the geographic variation among Asian countries. Using the Pubmed database, keywords that were employed included hip fracture, incidence rate, geographic variation, osteoporosis, and epidemiology. Articles were chosen based on the basis of (1) focus: studies that were said to specifically focus on geographic variation in hip fracture from different continents with a focus on Asia; (2) language: studies that were in English; (3) methods: studies that used statistical tests to examine hip fracture incidence rates. The highest hip fracture rates are seen in Scandinavian countries and the US and the lowest in African countries. Fracture rates are intermediate in Asian populations. Among different ethnic populations, the highest fracture rates are seen in Caucasians and the lowest in blacks. There is also a north-south gradient, particularly in Europe, where more hip fractures occur in North Europe compared to the South. 1. Introduction Osteoporosis is recognised as a major public health problem through its association with low trauma or fragility fracture. Osteoporotic hip fracture is an established health problem in the West over the last six decades and is increasingly being recognised as a growing problem in Asia [1]. With a rising life expectancy throughout the globe, the number of elderly individuals is increasing in every geographical region; the incidence of hip fracture is estimated to rise from 1.66 million in 1990 to 6.26 million in 2050 [2]. All osteoporotic fractures increase patient morbidity; however, the fractures of hip and vertebrae are associated with significant mortality. Hip fracture incidence increases exponentially with age and more so in women. With changing world population dynamics it has been estimated that more than half of these fractures will be seen in Asia by year 2050. Geographic and ethnic variation exists for hip fractures. The exact reasons for this geographic variation are ill understood but genetic factors, less bone mineral content, an aging population and environmental factors such as dietary factors and vitamin D levels are important in the pathogenesis of hip fracture. Understanding this changing epidemiology of hip fracture is therefore essential to develop strategies for the future with a special emphasis on Asia. 2. Methods This paper was conducted using the
Built Environment and Its Influences on Walking among Older Women: Use of Standardized Geographic Units to Define Urban Forms  [PDF]
Vivian W. Siu,William E. Lambert,Rongwei Fu,Teresa A. Hillier,Mark Bosworth,Yvonne L. Michael
Journal of Environmental and Public Health , 2012, DOI: 10.1155/2012/203141
Abstract: Consensus is lacking on specific and policy-relevant measures of neighborhood attributes that may affect health outcomes. To address this limitation, we created small standardized geographic units measuring the transit, commercial, and park area access, intersection, and population density for the Portland, Oregon metropolitan area. Cluster analysis was used to identify six unique urban forms: central city, city periphery, suburb, urban fringe with poor commercial access, urban fringe with pool park access, and satellite city. The urban form information was linkable to the detailed physical activity, health, and socio-demographic data of 2,005 older women without the use of administrative boundaries. Evaluation of the relationship between urban forms and walking behavior indicates that older women residing in city center were more likely to walk than those living in city periphery, suburb communities, and urban fringe with poor commercial access; however, these women were not significantly more likely to walk compared to those residing in urban fringe with poor park access or satellite city. Utility of small standardized geographic units and clusters to measure and define built environment support research investigating the impact of built environment and health. The findings may inform environmental/policy interventions that shape communities and promote active living.
Animal sounds: a human vantage point
Ekaterina Rakhilina
Oslo Studies in Language , 2011,
Abstract: Why is it that the lexicon is often shunned and ignored by linguists, or in other words, treated with disdain and generally considered to be the Ugly Duckling of the linguistic family? This paper is both an attempt to redress the balance and it is designed as a tentative, initial contribution to the study of verbs of sound. Here, the central focus is devoted to a small subsection of verbs of sound, namely to the verbs denoting animal sounds used with metaphorical reference to human beings. The paper also attempts to sketch possible situations and parameters which are relevant for human beings and which appear to be cross-linguistic universals. The discussion is for the most part focused on Russian but examples from other languages, such as English, German, Estonian, and so forth, are also included.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.