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911.
The main objectives of the study were: to investigate whether training on working memory (WM) could improve fluid intelligence, and to investigate the effects WM training had on neuroelectric (electroencephalography - EEG) and hemodynamic (near-infrared spectroscopy - NIRS) patterns of brain activity. In a parallel group experimental design, respondents of the working memory group after 30 h of training significantly increased performance on all tests of fluid intelligence. By contrast, respondents of the active control group (participating in a 30-h communication training course) showed no improvements in performance. The influence of WM training on patterns of neuroelectric brain activity was most pronounced in the theta and alpha bands. Theta and lower-1 alpha band synchronization was accompanied by increased lower-2 and upper alpha desynchronization. The hemodynamic patterns of brain activity after the training changed from higher right hemispheric activation to a balanced activity of both frontal areas. The neuroelectric as well as hemodynamic patterns of brain activity suggest that the training influenced WM maintenance functions as well as processes directed by the central executive. The changes in upper alpha band desynchronization could further indicate that processes related to long term memory were also influenced.  相似文献   
912.
913.
Brown和Bigler提出了儿童歧视知觉模型,分析了歧视知觉的三个影响因素:认知因素、情景因素和个体差异因素,每个因素都包含了多个影响儿童歧视知觉的子因素。该模型展示了这些因素影响儿童歧视知觉的机制。完善该模型需要探讨其与信息加工理论、发展群际理论、主观群体动力学模型的兼容性。歧视知觉的类型需要进一步细化,因此在综合主观群体动力学模型和发展模型的基础上提出了歧视知觉的分类方案。未来研究还要进一步探讨情绪、文化以及年龄因素对儿童歧视知觉的影响,并探讨该模型对歧视干预的意义。  相似文献   
914.
Selection of new geographies in which to expand is a key decision for businesses aspiring to go beyond the opportunities in the existing markets. The conventional approaches of market selection can only provide a set of systematic steps for problem solving without considering the relationships between the decision factors. Decision models based on statistical techniques are able to examine the relationship between decision factors but are unable to effectively assist decision makers in identifying the most promising market, particularly in terms of prioritizing across decision factors. Analytic Hierarchy Process (AHP) is a commonly used approach for choosing alternatives by prioritizing across multiple decision factors. The typical AHP modelling requires knowledge of criteria and/or alternatives along with their relative weights, generally elicited from field experts. Quite often, firms encounter situations where decision makers are aware of only the overall objective and a set of earmarked geographies for setting up market locations while being relatively unaware of decision criteria and relative weights. This precludes using AHP to identify promising market locations. This paper conceptualizes a market selection decision model that integrates AHP with statistical modelling techniques to identify the attractive market locations for the purpose of expansion. The model first uses principal component analysis and multiple regression to determine significant decision criteria and their weights. Thereafter, it applies AHP to prioritize the market locations across the decision criteria. This integrative approach is illustrated for identifying the attractive locations in rural markets for a steel firm in India. The major advantage of this approach is that unlike the existing models, it works in situations when firms have not enough knowledge about factors for evaluating alternative market locations. Another key advantage of the proposed model is that of economizing resources for data collection on variables representing decision factors. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
915.
Declarations of conciliation between private life and professional life based on three factors (sex, gender and positions) are studied in this paper. Our goals were (i) to show that conciliation between the different life spheres need to be considered both in terms of conflict and of life enrichment; (ii) and to demonstrate that the gender variable has combined effects with sex variables, as well as with positions variables, over the perception of work in relation to family interferences in terms of nature (conflict/enrichment), intensity and direction (family over work versus work over family). The study, conducted with 240 employees of low or high professional positions, based on SWING and BSRI scales, shows the moderating effect of gender on the perceptions of conciliation, whether enriching or conflicting. Our results also allow us to conclude that congruent adjustment (masculine domination) of the levels of our three factors constitute a protecting factor for employees, while an incongruent adjustment can constitute a risk factor, this being especially verified for women.  相似文献   
916.
917.
对男同性恋身体意象的研究有近30年的历史。男同性恋比男异性恋更容易出现负面身体意象、身体不满意和进食障碍等。男同性恋追求瘦而有肌肉的理想身体。针对这些特点, 研究者提出一些理论假设进行解释, 包括性客观化理论、内化同性恋污名、性别角色假设、进化心理学假设和AIDS/HIV假设等。未来研究要进行整合的和多样化的研究取向, 方法上采用以网络调查为主的定量研究和以现象学分析为主的定性研究。最后, 国内研究要更注重文化特异性。  相似文献   
918.
以初中二年级的学生为考察对象,探讨了音乐经验对不同层次的言语加工能力的促进作用,发现:在声音信号的加工层面,音乐经验对音高和时长信息感知能力的发展都有积极的促进作用;在语音意识层面,音乐经验的促进作用只局限于声调意识;在言语记忆方面,音乐经验可以促进言语材料在长时记忆中的保持。  相似文献   
919.
Abstract

HIV/AIDS knowledge, age at onset of sexual activity, perceptions of personal risk and peer norms were explored as correlates for risky sexual behaviors among college students. Ninety-nine male and 185 female college students completed a 66-item questionnaire. A majority reported being sexually active with most in mutually monogamous relationships or not currently in a sexual relationship. Multiple regression correlation analyses showed knowledge about HIV/AIDS to be very high but that this knowledge did not independently relate to the extent of risky behaviors. Perceptions of risk were positively related to number of partners and single-time partners but not condom usage. In contrast to previous studies, perceived peer norms did not independently relate to behaviors. Instead, age at first intercourse was found to have substantial overlap with current perceptions, attitudes, and likelihood for engaging in risky behaviors. The necessity for including previous behaviors in analyses of the impact of attitudes and perceived norms on behavioral intentions is discussed.  相似文献   
920.
Abstract

Pre-adolescents and adolescents (N= 80, aged 10, 12, 15, and 18 years) were tested on their knowledge of HIV/AIDS. Knowledge was assessed using a self-report questionnaire (examining levels of factual knowledge) and a semi-structured interview (examining cognitive developmental levels of understanding). Examination of the developmental shifts in understanding of HIV/AIDS revealed an increase in conceptual complexity on causal and prevention dimensions. The main conceptual changes included a shift from single cause to multiple cause solutions and a shift from identifying surface or immediate features to implicating less salient features. Additionally, with age, concepts about HIV/AIDS were increasingly organised around internal, physiological principles. Questionnaire responses yielded significant age-related increases in knowledge. Level of knowledge, as measured by the questionnaire, was higher than that assessed by the interview for the three youngest age groups. Thus, factual information acquired about HIV/AIDS is not automatically accompanied by understanding. In light of these findings the past conclusion that adolescents have high levels of knowledge of HIV/AIDS is questioned.  相似文献   
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