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41.
认知风格、内外向性、情绪稳定性与图形推理效果的关系 总被引:7,自引:1,他引:6
采用EFT、EPQ和RSPM-CR量表对156名理科大学生进行测量研究,结果发现:场独立性认知风格在图形系统变化、系列关系、抽象推理方面,较场依存性有明显优势;情绪稳定性高者图形推理的总体效果显著优于情绪稳定性低者;内向性者与外向性者的图形推理效果无显著差异;认知风格、情绪稳定性与图形推理总分有显著正相关,认知风格的正向预测力居首位。 相似文献
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ObjectivesTo assess the effects of voluntarily reducing postural sway on postural control and to determine the attention level needed to do so in healthy adults (n = 16, 65.9 ± 9.7) and persons with PD (n = 25, 65.8 ± 9.5 years). Tasks: quiet and still standing conditions with and without a category task. Cognitive performance, center of pressure (CoP) displacement variability (RMSCoP) and velocity (VCoP) were assessed in the anterior-posterior (AP) and medial-lateral (ML) directions.Controls showed larger RMSCoP (AP) and VCoP (AP and ML) during still versus quiet standing (p < 0.01), while the PD group demonstrated no changes. In the PD group, RMSCoP and VCoP (ML) increased in still standing when performed with the cognitive task (p < 0.05). In both groups, cognitive responses decreased in still standing (p < 0.05).In PD, attempting to reduce postural sway did not affect postural control under single task conditions, however ML CoP variability and velocity did increase as a dual task. In older adults, increased displacement and velocity in both AP and ML directions was observed during single, but not dual task conditions. Therefore standing still might not be an adequate postural strategy as it increases the attentional demand and affects motor performance, putting persons with PD at greater risk for falls. 相似文献
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Estimates of intelligence in young children with neurodevelopmental disorders are critical for making diagnoses, in characterizing symptoms of disorders, and in predicting future outcomes. The limitations of standardized testing for children with developmental delay or cognitive impairment are well known: Tests do not exist that provide developmentally appropriate material along with norms that extend to the lower reaches of ability. Two commonly used and interchanged instruments are the Mullen Scales of Early Learning (MSEL), a test of developmental level, and the Differential Ability Scales, second edition (DAS-II), a more traditional cognitive test. We evaluated the correspondence of contemporaneous MSEL and the DAS-II scores in a mixed sample of children aged 2–10 years with autism spectrum disorder (ASD), non-ASD developmental delays, and typically developing children across the full spectrum of cognitive ability. Consistent with published data on the original DAS and the MSEL, scores on the DAS-II and MSEL were highly correlated. However, curve estimation revealed large mean differences that varied as a function of the child’s cognitive ability level. We conclude that interchanging MSEL and DAS-II scores without regard to the discrepancy in scores may produce misleading results in both cross-sectional and longitudinal studies of children with and without ASD, and, thus, this practice should be implemented with caution. 相似文献
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Polypropylene (PP)/multi-wall carbon nanotube (MWCNT) nanocomposites were prepared via a melt compounding method using a twin-screw extruder. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to study the crystallization and thermal stability of the nanocomposites. The DSC analysis results revealed that the existence of MWCNTs in a PP matrix, which acted as a nucleating agent enhancing the crystallization process of PP matrix. This behaviour was manifested by an increase in the crystallization temperature and crystallinity index of the nanocomposites. Additionally, the TGA results showed that the addition of MWCNTs dramatically increased the thermal stability of the PP/MWCNT nanocomposites. Generally, MWCNT type C-70P showed improved crystallization and better thermal stability of the nanocomposites compared to type C-150P. 相似文献
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There is growing evidence for the relationship between working memory and academic attainment. The aim of the current study was to investigate whether working memory is simply a proxy for IQ or whether there is a unique contribution to learning outcomes. The findings indicate that children’s working memory skills at 5 years of age were the best predictor of literacy and numeracy 6 years later. IQ, in contrast, accounted for a smaller portion of unique variance to these learning outcomes. The results demonstrate that working memory is not a proxy for IQ but rather represents a dissociable cognitive skill with unique links to academic attainment. Critically, we find that working memory at the start of formal education is a more powerful predictor of subsequent academic success than IQ. This result has important implications for education, particularly with respect to intervention. 相似文献
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Stability or sensitivity analysis is an important topic in data analysis that has received little attention in the application of multidimensional scaling (MDS), for which the only available approaches are given in terms of a coordinate‐based analytical jackknife methodology. Although in MDS the prime interest is in assessing the stability of the points in the configuration, this methodology may be influenced by imprecisions resulting from the inherently necessary Procrustes method. This paper proposes an analytical distance‐based jackknife procedure to study stability and cross‐validation in MDS in terms of the jackknife distances, which is not influenced by the Procrustes method. For each object, the corresponding jackknife estimated points are considered as naturally clustered points, and stability and cross‐validation are analysed in terms of the MDS distances arising from the jackknife procedure, on the basis of a weighted cluster‐MDS algorithm. A jackknife‐relevant configuration is also proposed for cross‐validation in terms of coordinates, in a cluster‐MDS framework. 相似文献