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51.
An IRT analysis of motive questionnaires: The Unified Motive Scales   总被引:1,自引:0,他引:1  
Multiple inventories claiming to assess the same explicit motive (achievement, power, or affiliation) show only mediocre convergent validity. In three studies (= 1685) the structure, nomological net, and content coverage of multiple existing motive scales was investigated with exploratory factor analyses. The analyses revealed four approach factors (achievement, power, affiliation, and intimacy) and a general avoidance factor with a facet structure. New scales (the Unified Motive Scales; UMS) were developed using IRT, reflecting these underlying dimensions. In comparison to existing questionnaires, the UMS have the highest measurement precision and provide short (six-item) and ultra-short (three-item) scales. In a fourth study (= 96), the UMS demonstrated incremental validity over existing motive scales with respect to several outcome criteria.  相似文献   
52.
The present study explored the influence of dispositional perfectionism (i.e. perfectionistic concerns and perfectionistic strivings) on tension and performance under low or high experimentally induced stress. Results support the moderating role of perfectionism concerning tension and indicate that stress-related processes underlie the vulnerability of perfectionistic concerns. In addition, buffering effects of perfectionistic strivings were found, supporting the 2 × 2 model of dispositional perfectionism by Gaudreau and Thompson (2010). No evidence was found for the moderating role of perfectionistic strivings concerning performance, but results provide evidence for positive effects of perfectionistic concerns on performance.  相似文献   
53.
This study investigated how early experience with racial discrimination affected the subsequent risky sexual behaviors of a diverse sample of African American youths (N = 745). The analyses focused on 3 risk-promoting factors thought to mediate the hypothesized discrimination → risky sex relation: negative affect, affiliation with deviant peers, and favorable attitudes toward risky sex. In addition, attentive parenting was examined as a protective factor. Analyses using structural equation modeling revealed that youths who perceived more racial discrimination at age 10 or 11 were engaging in more sexual risk taking at age 18 or 19. This relation was mediated by the hypothesized risk-promoting factors via pathways that were consistent with our conceptual model. Results also indicated a prospective reciprocal relation between parenting and children's deviant affiliations: deviant peer affiliations at age 10 or 11 predicted more attentive parenting behaviors by the parents; this response from the parents, in turn, predicted relatively fewer deviant affiliations when the youths were 15 or 16. Study findings are discussed in terms of their relevance to the disproportionately high rates of sexually transmitted infections among African Americans.  相似文献   
54.
While the gender gap in mathematics and science has narrowed, men pursue these fields at a higher rate than women. In this study, 165 men and women at a university in the northeastern United States completed implicit and explicit measures of science stereotypes (association between male and science, relative to female and humanities), and gender identity (association between the concept “self” and one’s own gender, relative to the concept “other” and the other gender), and reported plans to pursue science-oriented and humanities-oriented academic programs and careers. Although men were more likely than women to plan to pursue science, this gap in students’ intentions was completely accounted for by implicit stereotypes. Moreover, implicit gender identity moderated the relationship between women’s stereotypes and their academic plans, such that implicit stereotypes only predicted plans for women who strongly implicitly identified as female. These findings illustrate how an understanding of implicit cognitions can illuminate between-group disparities as well as within-group variability in science pursuit.  相似文献   
55.
To examine the reciprocal relations between teacher-child relationships and children's behavior problems, the authors analyzed cross-lagged longitudinal data on teacher-child relationships and children's internalizing and externalizing problems using a structural equation modeling approach. The homeroom teachers of 105 first-year preschoolers aged 2-3 years filled in the Student-Teacher Relationship Scale and the Child Behavior Checklist/2-3, first at 3 months after the children's preschool entrance and then at the end of the first preschool year. Results showed significant cross-wave reciprocal relations between externalizing problems and teacher-child conflict and significant cross-wave relation from early internalizing problems to later teacher-child conflict. However, the cross-wave associations between internalizing and externalizing problems and teacher-child closeness were not significant.  相似文献   
56.
A female physician who was serving as a first-year medicine resident in Manhattan in September 2001 writes this paper. It details her experience of signing up for military service as a result of the September 11th attack on the United States. She lays out the surroundings, atmosphere, and reactions of those around her during the attack and details her own personal motivations for joining the military, her need to take control and help those in need heal while also trying to heal herself. Grateful, yet haunted by her experience, she provides an intimate glimpse into her time serving as a combat physician at a trauma hospital in Balad, Iraq during the 2007 military surge. A trained geriatrician and palliative care physician she recounts the stories of several patients that have forever shaped her life and explores the contradictions and ethical challenges she faced while caring for them ultimately struggling with the uncertainty of whether what she was truly doing was good for those she served or herself.  相似文献   
57.
Yang H  Jin G  Ren D  Luo S  Zhou T 《Brain and cognition》2011,76(1):206-210
This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the β-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the β-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system.  相似文献   
58.
已有大量研究揭示了近似数量系统与计算流畅性的相关关系, 但缺少对二者关系原因的系统检验与论证。视觉形状知觉假设有别于传统的数量领域特异性解释, 认为对形状的快速知觉是近似数量系统与计算流畅性的共同认知机制, 即视觉形状的快速知觉能力可以解释二者之间的相关关系。近似数量系统和计算流畅性在加工过程中依赖对形状的快速知觉, 二者在加工过程中都涉及了复杂视觉刺激的快速处理。视觉形状知觉假设得到了一系列研究结果的支持, 但局限在视觉形状知觉与二者关系的探讨上, 视觉形状知觉在二者关系中作用的加工机制仍不清楚。未来研究需要结合多种研究方法和技术, 多角度深入探讨视觉形状知觉在二者关系中作用的认知与脑机制, 并将研究结果应用于数学课堂教学和计算困难的干预中。  相似文献   
59.
In agreement with the hypothesis of differential treatment of the intrinsic (color, shape, category…) and extrinsic (position, orientation…) visual characteristics along the ventral and dorsal pathways of the visual system (Milner & Goodale, 1995), the study of temporal order judgment (TOJ) of the variation of two visual attributes highlighted the perceptual asynchrony even though these changes occur synchronously. In this context, we investigated the role of action in the perception of perceptual asynchrony, especially the effect of a reaching movement on the TOJ of position and color changes of a target occurring at different times of movement execution. In the absence of voluntary action, the point of subjective simultaneity (PSS) shows that the color changes must occurr 46.6 ms before the change of position to give rise to a synchronous perception of these two changes. Performing a reaching movement reduced significantly the PSS (12.4 ms), but only if the changes occur near movement end-point. If changes occur during movement execution, the PSS (40.2 ms) was not different from that obtained in the perceptual condition. These results suggest that endogenous signals associated with voluntary motor action contribute to the reduction of perceptual asynchrony in relation to the goal of the action. We discuss the possibility that, in the context of the action, the motor system contributes to the binding of objects sensory attributes as well as to the sense of agency.  相似文献   
60.
采用记忆更新任务,实验1要求被试分别更新3个和4个记忆项目,并设置不转换、控制转换和抑制转换条件,考察记忆集对注意焦点转换及其返回抑制的影响;实验2操纵两次更新同一记忆项目之间对其它记忆项目更新的次数(2次、3次及3次以上),在实验1基础上,考察返回抑制中项目抑制状态的消退过程.结论:随记忆集增加,转换代价增大,而返回抑制效应消失;当注意焦点对其它记忆项目更新2次时,之前被抑制项目的抑制状态可完全消退.  相似文献   
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