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991.
This study examined whether children with mathematical difficulties (MDs) or comorbid mathematical and reading difficulties have a working memory deficit and whether the hypothesized working memory deficit includes the whole working memory system or only specific components. In the study, 31 10-year-olds with MDs and 37 10-year-olds with both mathematical and reading difficulties were compared with 47 age-matched and 50 younger controls (9-year-olds) on a number of working memory tasks. Compared with the age-matched controls, both groups of children with MDs performed worse on tasks tapping the central executive (e.g., visual matrix span) and the phonological loop (e.g., word span). More important, the MD group performed worse than the younger controls on the counting span task, whereas the group with comorbid mathematical and reading difficulties performed worse on the counting span task and the visual matrix span task. These findings provide support for the assumption that children with MDs have a working memory deficit. More specifically, children with MDs have a central executive deficit connected to concurrent processing and storage of numerical and visual information. 相似文献
992.
探讨平板运动试验(TET)结合颈动脉斑块检测在诊断冠心病的临床意义。对166例疑诊冠心病患者进行冠状动脉造影(CAG),TET,颈动脉斑块检查,以CAG的诊断结果为金标准,分析TET,颈动脉斑块检查,TET结合颈动脉斑块检查诊断冠心病的敏感度、特异度。比较三者诊断冠心病的敏感度、特异度。三者敏感度分别为71.4%、64.3%、96.0%。特异度分别为65%、60.0%、82.4%。后者较前两者敏感度、特异度P<0.05。TET结合颈动脉斑块检查可显著提高冠心病的诊断率,不失为CAG前的筛选方法。 相似文献
993.
994.
Life-long environmental enrichment differentially affects the mnemonic response to estrogen in young, middle-aged, and aged female mice 总被引:2,自引:0,他引:2
The present study was designed to examine whether life-long exposure to standard or enriched housing affects the ability of estrogen to improve spatial and object memory throughout the lifespan. Three-week-old female mice were maintained in standard or enriched housing up to and through ovariectomy and behavioral testing at 5, 17, or 22 months of age. Spatial memory was tested in the Morris water maze and object memory was tested using an object recognition task. Immediately after training each day, mice were injected intraperitoneally with vehicle or 0.2 mg/kg 17beta-estradiol. Among young females, object recognition was enhanced by estradiol alone, an effect that was reduced by enrichment. In contrast, spatial water maze performance was impaired by estradiol alone, but improved by the combination of both estradiol and enrichment. At middle-age, object recognition was enhanced by estradiol or enrichment alone, and the combination of both treatments. Spatial memory in the water maze was also improved by both treatments at middle-age, but the beneficial effects of estradiol were limited to standard-housed females. Finally, whereas enrichment in aged females significantly enhanced performance in both tasks, estradiol had no effect at this age in either task. In total, the data indicate that life-long enrichment can significantly alter the extent to which estradiol affects memory in mice throughout the lifespan. Importantly, the interaction between these treatments is highly dependent on age and type of memory tested. 相似文献
995.
Virginie Bonnot 《Journal of experimental social psychology》2007,43(6):857-866
It has long been argued that stigmatized individuals can ultimately internalize the stereotype alleging their inferiority. The present article investigated whether the internalization of the reputation of math inferiority that targets women can affect their math performance and whether this influence is caused by a disruption of working memory. A first study showed that stereotype endorsement had a significant impact on women’s statistic performance by lowering their self-evaluation of math ability even when controlling for prior achievement. A second study was designed to assess the possibility that the lower math performance displayed by women with low self-evaluation of math ability was due to interference in working memory. Using a dual task paradigm, this study showed that indeed women with low math self-evaluation displayed more errors and spent more time solving additions than women with high math self-evaluation, but mainly on difficult items of the dual task. The findings, which are congruent with an explanation in terms of a temporary disruption of working memory, are discussed. 相似文献
996.
O'Toole C Barnes-Holmes D Smyth S 《Journal of the experimental analysis of behavior》2007,88(2):263-283
Participants were trained in a series of interrelated conditional discriminations that aimed to establish four 4-member equivalence classes (i.e., A1-B1-C1-D1, A2-B2-C2-D2, A3-B3-C3-D3, A4-B4-C4-D4). During this training, the four A stimuli (i.e., A1, A2, A3, and A4) were compounded with pictures containing positive or negative evaluative functions (A1/A2 negative & A3/A4 positive). The transfer of evaluative functions to directly and indirectly related members of the equivalence classes (i.e., B, C, and D stimuli) was measured using an Implicit Association Test (IAT). During consistent test blocks, participants were required to press the same response key for target words that were related to those A stimuli that possessed similar evaluative functions (A1/A2-left key & A3/A4-right key). During inconsistent test blocks, target words that were related to those A stimuli with different evaluative functions were assigned to the same response key (A1/A4-left key & A2/A3-right key). Results showed that all 8 participants, who passed a matching-to-sample equivalence test following the IAT, responded more rapidly on consistent relative to inconsistent test blocks. This typical IAT effect was not observed for those participants who did not pass the equivalence test. The results suggest that the IAT effect may arise from formally untested derived relations, and supports the argument that such relations could provide a valid behavioral model of semantic categories in natural language. 相似文献
997.
Harry Brighouse 《Res Publica》2007,13(2):147-158
This paper is an engagement with Equality by John Baker, Kathleen Lynch, Judy Walsh and Sara Cantillon. It identifies a dilemma for educational egalitarians, which
arises within their theory of equality, arguing that sometimes there may be a conflict between advancing equality of opportunity
and providing equality of respect and recognition, and equality of love care and solidarity. It argues that the latter values
may have more weight in deciding what to do than traditional educational egalitarians have usually thought. 相似文献
998.
999.
轻度认知损伤(Mild cognitive impairment,MCI)是介于正常老化与痴呆之间的过渡阶段,表现为与年龄和教育程度不相称的认知功能减退。本文回顾了近期有关MCI语义记忆的研究,分析比较了各研究的实验任务及结果,得出MCI患者存在一定程度的由多种原因造成的语义记忆损伤,语义记忆测验对MCI的早期筛查和转归预测有重要作用。最后指出将来的研究需要将包括语义记忆成分在内的多种认知测验相结合,以便及早发现有可能发展为痴呆的危险个体并开展相应干预。 相似文献
1000.