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排序方式: 共有1893条查询结果,搜索用时 15 毫秒
81.
Leritz Elizabeth C.; Salat David H.; Milberg William P.; Williams Victoria J.; Chapman Caroline E.; Grande Laura J.; Rudolph James L.; Schnyer David M.; Barber Colleen E.; Lipsitz Lewis A.; McGlinchey Regina E. 《Canadian Metallurgical Quarterly》2010,24(2):199
Although hypertension is a major risk factor for cerebrovascular disease (CVD) and is highly prevalent in African Americans, little is known about how blood pressure (BP) affects brain–behavior relationships in this population. In predominantly Caucasian populations, high BP is associated with alterations in frontal–subcortical white matter and in executive functioning aspects of cognition. We investigated associations among BP, brain structure, and neuropsychological functioning in 52 middle–older-age African Americans without diagnosed history of CVD. All participants underwent diffusion tensor imaging for examination of white matter integrity, indexed by fractional anisotropy (FA). Three regions of interest were derived in the anterior (genu) and posterior (splenium) corpus callosum and across the whole brain. A brief neuropsychological battery was administered from which composite scores of executive function and memory were derived. Blood pressure was characterized by mean arterial blood pressure (MABP). When controlling for age, higher MABP was associated with lower FA in the genu, and there was a trend for this same relationship with regard to whole-brain FA. When the sample was broken into groups on the basis of treatment for BP regulation (medicated vs. nonmedicated), MABP was related to genu and whole-brain FA only in the nonmedicated group. Neither MABP nor FA was significantly related to either neuropsychological composite score regardless of medication use. These data provide important evidence that variation in BP may contribute to significant alterations in specific neural regions of white matter in nonmedicated individuals without symptoms of overt CVD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Siedlecki Karen L.; Manly Jennifer J.; Brickman Adam M.; Schupf Nicole; Tang Ming-Xin; Stern Yaakov 《Canadian Metallurgical Quarterly》2010,24(3):402
Objective: The purpose of this study was to examine whether neuropsychological tests translated into Spanish measure the same cognitive constructs as the original English versions. Method: Older adult participants (N = 2,664), who did not exhibit dementia from the Washington Heights Inwood Columbia Aging Project (WHICAP), a community-based cohort from northern Manhattan, were evaluated with a comprehensive neuropsychological battery. The study cohort includes both English (n = 1,800) and Spanish speakers (n = 864) evaluated in their language of preference. Invariance analyses were conducted across language groups on a structural equation model comprising four neuropsychological factors (memory, language, visual-spatial ability, and processing speed). Results: The results of the analyses indicated that the four-factor model exhibited partial measurement invariance, demonstrated by invariant factor structure and factor loadings but nonequivalent observed score intercepts. Conclusion: The finding of invariant factor structure and factor loadings provides empirical evidence to support the implicit assumption that scores on neuropsychological tests are measuring equivalent psychological traits across these two language groups. At the structural level, the model exhibited invariant factor variances and covariances. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
According to classical theories, automatic processes are autonomous and independent of higher level cognitive influence. In contrast, the authors propose that automatic processing depends on attentional sensitization of task-congruent processing pathways. In 3 experiments, the authors tested this hypothesis with a modified masked semantic priming paradigm during a lexical decision task by measuring event-related potentials (ERPs): Before masked prime presentation, participants attended an induction task either to semantic or perceptual stimulus features designed to activate a semantic or perceptual task set, respectively. Semantic priming effects on the N400 ERP component, an electrophysiological index of semantic processing, were obtained when a semantic task set was induced immediately before subliminal prime presentation, whereas a previously induced perceptual task set attenuated N400 priming. Across experiments, comparable results were obtained regardless of the difficulty level and the verbal or nonverbal nature of the induction tasks. In line with the proposed attentional sensitization model, unconscious semantic processing is enhanced by a semantic and attenuated by a perceptual task set. Hence, automatic processing of unconscious stimuli is susceptible to top-down control for optimizing goal-related information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
目的 人工智能的发展逐渐渗透到人文艺术领域,其中智能辅助艺术创作引领了学科领域发展新趋势,人工智能(AI)与传统美术图案的结合为传统美术的创新与传承带来了新的活力。研究对公众如何认知经由人工智能转译后的传统美术图案及影响此类认知的主要因素。方法 研究运用人工智能图像转译技术,将6幅中国传统艺术图案进行风格迁移和重构,并以网上问卷调查的方式,收集355名受试者对原图案和转译图案的情感评价与审美理解,进而对公众的认知结构进行解构与分析。讨论 研究发现,公众对经由人工智能转译后的传统美术图案的风格契合度的情感认知路径是多元复杂的,其涉及美感、色彩、愉悦、工艺、构图等多重元素的因素组合。结论 公众对人工智能转移后的美术图案的情感认知,除了现有研究所侧重的色彩与纹理等因素,生成图案的整体感以及其展现的情绪色彩也能够对公众契合度认知产生核心影响。 相似文献
85.
目的 通过分析用户疏散过程与使用消防疏散图过程的行为与认知,探讨消防疏散图产品定位和视觉设计策略。方法 通过行为观察、访谈、实验方法分析用户疏散行为与认知过程,梳理用户认知要点和需求;通过行为观察、访谈方法,结合认知理论,分析用户使用消防疏散图行为与认知过程;采用眼动仪实验和主观评价获取数据,并进行相关性分析,分析用户使用消防疏散图认知过程的关键视觉影响因子。结论 梳理了用户消防疏散的行为过程、所需信息和信息区域;梳理了消防疏散图中影响用户认知的视觉影响因子;通过眼动仪实验获取了用户使用疏散图的认知效率数据,并分析了视觉影响因子与认知效率的相关性。在以上研究基础上提出消防疏散图的原则与策略。 相似文献
86.
目的了解南京市江宁地区火锅店锅底食品添加剂的应用情况及火锅店采购人员和顾客对食品添加剂的认识,提出相关对策,为相关部门采取积极有效的措施提供理论依据。方法采用随机抽样的方法抽取江宁区20家火锅店,并对这20家火锅店食品添加剂的使用情况进行调查。同时使用自制问卷调查表调查火锅店采购人员对食品添加剂的认知情况,并采用分层整群抽样的方法调查300名消费者对食品添加剂的认知情况。结果南京市江宁地区火锅店锅底食品添加剂在调味品中的应用较为普遍。食品安全等级较低,规模较小及平均消费较低的火锅店底料中食品添加量较多;采购人员及普通消费对食品添加剂的普遍认识一般。结论相关部门应加强对火锅店的监管,采取积极有效的措施,提高火锅店采购人员及消费者对食品添加剂的认知程度。 相似文献
87.
建筑物化阶段的CO2排放时间集中、绝对量大,是建筑节能减排的研究重点。构建了办公建筑物化阶段CO2排放的计算模型,包括建材、设备生产与运输的CO2排放,以及施工过程的CO2排放。利用该计算模型,分析计算了78栋办公建筑物化阶段的CO2排放量。平均来看,物化阶段的碳排放量为326.75kg/m2;随着建筑高度的增加单位面积碳排放明显增加,超高层建筑的单位面积碳排放量是多层建筑的1.5倍;土建工程的碳排放量占到物化阶段的75%左右,而钢筋、混凝土、砂浆、墙体材料的碳排放量占到了土建工程的80%以上。分别以建筑层数和建材用量为自变量做了办公建筑物化阶段CO2排放量的预测模型,通过统计学的分析对比,发现以钢筋、混凝土和墙体材料为自变量的预测公式可以很好地预测建筑物化阶段的碳排放。 相似文献
88.
刘志成 《昆明冶金高等专科学校学报》2014,(6):83-87
一词多义是语言中非常重要的语言现象,具有重要的研究价值。对典型人体词"nose"的一词多义的认知研究,不仅有利于揭示词义拓展的基本规律、词义拓展的认知机制,而且对于揭示认知主体的思维模式和认知特点也具有重要的意义。从认知的角度对作为修辞手段的隐喻和转喻进行了新的探索,指出二者不仅是重要的思维模式和认知手段,也是一词多义的认知机制。通过一词多义的词义网络,揭示出词义的拓展不是任意的,隐喻和转喻在词义拓展过程中是相互交织的,进一步证实语言不是自治的、封闭的系统,从而在一定程度上驳斥了索绪尔的语言"任意说"的观点。 相似文献
89.
90.
This study investigated the effect of contrast in neutral-, warm-, and cool-colored spaces on spatial memory. Spatial memory was measured in terms of architectural scale and recollection of architectural elements and furniture. Participants (N = 114) viewed a short virtual simulation video of a residential studio and were asked to sketch a map of the architectural elements on distributed grid paper. Spatial memory was measured in terms of scale, and item recall rate. Contrast and hue had no significant effect on the memorization of proportional scale. However, high-contrast schemes allowed for a significantly higher recollection of architectural elements than low-contrast schemes. In comparing the effect of hues, a significant difference was seen in recalling detailed furniture and lighting items. Participants reported significantly better spatial memory of neutral and warm color schemes than of cool color schemes. There was no interaction effect between contrast and hue in the color combinations. These results can be applied in the design of color schemes for architectural spaces requiring enhanced spatial cognition and memory. 相似文献