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991.
Grounding spatial language in perception: An empirical and computational investigation. 总被引:1,自引:0,他引:1
The present paper grounds the linguistic categorization of space in aspects of visual perception; specifically, the structure of projective spatial terms such as above are grounded in the process of attention and in vector-sum coding of overall direction. This is formalized in the attentional vector-sum (AVS) model. This computational model accurately predicts linguistic acceptability judgments for spatial terms, under a variety of spatial configurations. In 7 experiments, the predictions of the AVS model are tested against those of 3 competing models. The results support the AVS model and disconfirm its competitors. The authors conclude that the structure of linguistic spatial categories can be partially explained in terms of independently motivated perceptual processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Kathrin Strebel Ulrike Rolle-Kampczyk Annegret Kindler Uwe Schlink 《The Science of the total environment》2010,408(18):3931-3942
This paper presents an investigation into spatial risk differences over small distances for the Helicobacter pylori infection in the city of Leipzig, Germany and two rural districts. A model, using Bayesian inference, was developed that adjusts the risk for individual-specific factors, and for spatial or individual over-dispersion, respectively. Additionally, the model takes into account conditional spatial autocorrelation. We found a significant positive association to the H. pylori infection risk for: “more than three children live in the household” (OR = 2.4, p = 0.001), “more persons live per sq.m than average” (OR = 1.4, p = 0.03), “home situated at main road” (OR = 1.4, p = 0.04) and “using well water” (OR = 2.3, p = 0.05). A protective effect was identified for “travelled to low prevalence region” (OR = 0.4, p < 0.0001) and “born in Germany” (OR = 0.2, p < 0.0001). Three administrative areas with significantly increased spatial risk were identified: one in the rural district and two in the city of Leipzig. The model explained 24.9% of the total deviance. Contrary to expectations, the largest part of deviance of the data was not explained by the identified significant risk factors, but by individual-specific heterogeneities. We conclude that further - so far not discussed - factors influence the risk and the spatial variation of the H.pylori infection. Furthermore, from the results we speculate about a possible impact of long-time air pollution and surface water. 相似文献
993.
994.
Evaluated the contribution of reduced contrast sensitivity and retinal illuminance to the age-related deficit on the temporal resolution of suprathreshold spatial stimuli among an elderly group (55-72 yr olds) and two young groups (18-28 yr olds). The discrimination of counterphase flicker was measured in optimally refracted young and elderly observers for sinusoidal gratings of three spatial frequencies (1, 4, and 8 cycles per degree) at three contrast levels (0.11, 0.33, and 0.66). Age deficits in flicker discrimination at the two higher contrast levels and at the two lower spatial frequencies were unrelated to observer contrast sensitivity. Flicker discrimination of young observers who carried out the task through .5 ND filters to simulate a two-thirds reduction of retinal illuminance in the older eye, was similar to that of the elderly observers. An age-related reduction in retinal luminance appears to be a major determinant of the age-related spatiotemporal deficit at suprathreshold contrast levels, although neural factors may also be involved. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Wilton L. A. K.; Baird A. L.; Muir Janice L.; Honey R. C.; Aggleton John P. 《Canadian Metallurgical Quarterly》2001,115(4):861
This study sought to characterize the effects of removing the nuclei of primary importance in relaying the thalamic head direction signal to the hippocampal formation (the anterior dorsal [AD] and lateral dorsal [LD] nuclei) on the performance of a variety of spatial and nonspatial tasks. The results indicate that combined excitotoxic lesions of the AD and LD nuclei produce marked deficits on a variety of spatial tasks. These tasks included T-maze alternation and the ability to locate a hidden platform set at a fixed distance and fixed direction from a beacon in a Morris water maze. Although object recognition appeared unaffected, marked impairments were found in the ability to detect when an object was placed in a novel position (object-in-place memory). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Presents research that tests the empirical validity of the construct of Central Conceptual Structure (SCC) proposed by R. Case to account for children's conceptual development in 3 distinct domains: number, space, and social cognition. Three batteries of tasks (numerical, spatial, and narrative) were translated and administered to 69 6–10 yr old French children. The experiment was designed to verify 3 hypotheses relative to the development of SCC: the 1st concerns developmental synchrony between the numerical, spatial and narrative SCC; the 2nd individual differences in the elaboration of SCC; and the 3rd, relation between treatment capacities and levels of conceptual structuring. Results show that the developmental synchrony postulated within SCC is not generalized to all domains and age levels; individual patterns of performance are mostly similar; and the positive correlations observed between span measures and battery scores are not sufficient to validate the relation between treatment capacities and conceptual structuring. The limits of the SCC construct both in characterizing cognition at different age levels and specifying children's reasoning in different domains of knowledge are discussed with regard to the role attributed by Case to the general capacity of treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
研究了M1位三元NZP陶瓷组成对物相及晶格参数的影响,探讨了热膨胀有重要作用的组成与晶格参数之间的关系。 相似文献
998.
The Journal of Applied Psychology's call for theoretical models and conceptual analyses brought a terrific response. The first set of articles accepted in response to the call appeared in the December 2004 issue. This installment contains the second set of articles. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Depiction of precipitation change by elevation in an areaindicates the possibilities of orographic rainfall occurrencesin the mountainous regions. In general, precipitation increaseswith elevation but sometimes inverse cases occur locally due toorographic and meteorological features of the area. Inpractice, prior to any quantitative modeling, qualitativeassessments and interpretations help to have sound foundationsin search for a suitable model. In this article, standardizedpoint cumulative semivariogram (SPCSV) methodology is employedfor identification of the precipitation-elevationrelationship. According to relative positions of theprecipitation and elevation SPCSVs four different precipitationcategories are suggested. The application of the methodologyproposed is presented for the precipitation records from YuccaMountain, Nevada, U.S.A. 相似文献
1000.
C. J. R. Sheppard 《Journal of microscopy》1989,154(3):237-241
A simple analytic expression is given for the axial resolution of a confocal fluorescence microscope. The expression, which is based on the spatial frequency cut-off criterion of resolution, is valid for high aperture optics and arbitrary fluorescence wavelength. 相似文献