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891.
采用线索Go/Nogo任务,运用ERPs技术考察了老年人和青年人在自动化情绪调节上的差异。ERPs结果显示:⑴愉快面孔比中性面孔诱发的Go-N2波幅较小,潜伏期较短;Nogo-P3波幅较大,潜伏期较短,表明情绪面孔比中性面孔更能吸引注意;⑵在愉快面孔上,老年组比青年组的Go/Nogo-P3波幅大、潜伏期差异不显著;在悲伤面孔上,老年组比青年组的Go/Nogo-P3波幅大,Nogo-P3潜伏期长,说明老年组比青年组更加抑制对悲伤面孔的反应,老年人在自动化情绪调节中表现出一定程度的积极效应。  相似文献   
892.
Research has shown that academic risk taking—the selection of school tasks with varying difficulty levels—affords important implications for educational outcomes. In two experiments, we explored the role of cognitive processes—specifically, global versus local processing styles—in students’ academic risk-taking tendencies. Participants first read a short passage, which provided the context for their subsequent academic risk-taking decisions. Following which, participants undertook the Navon’s task and attended to either global letters or local letters only, i.e., were either globally or locally primed. The effects of priming on academic risk taking were then assessed using a perception-based measure (Experiment 1) and a task-based measure (Experiment 2). Experiment 1 provided preliminary evidence, which Experiment 2 confirmed, that globally focused individuals took more academic risk than did locally focused individuals after controlling for participants’ need for cognition (how much they enjoy effortful cognitive activities). Additionally, the inclusion of and comparisons with a control group in Experiment 2 revealed that locally focused participants drove the observed effects. The theory of predictive and reactive control systems (PARCS) provides a cogent account of our findings. Future directions and practical applications in education are discussed.  相似文献   
893.
Several studies suggest impaired executive functions (EFs) in children with externalizing behavior problems and average intelligence (e.g., IQ > 85). Even though children with mild to borderline intellectual disabilities (MBID) are at higher risk of developing externalizing behavior problems compared to children with average intelligence, it is not yet clear if impaired EFs are also associated with the occurrence of externalizing behavior problems in children with MBID. In the current study, we therefore assessed three EF components (inhibition, cognitive flexibility, and working memory) as well as processing speed in children with MBID and externalizing behavior problems (= 71) versus children with MBID with no such problems (= 70). This was accomplished using a well-established computerized test battery. Even after IQ was controlled for, the children with MBID and externalizing behavior problems showed more impaired working memory performance. Differences for inhibition performance and processing speed were also found but less consistent across the tasks used to measure these aspects of EF. Cognitive flexibility was not more impaired in children with both MBID and externalizing behavior problems relative to children with MBID only. Our findings highlight working memory as a potential target to enhance the treatment of children with MBID and externalizing behavior problems.  相似文献   
894.
Wenli Fan 《亚洲哲学》2017,27(4):292-308
The phenomenon of recognition is a point of contention in the debate between the orthodox Hindus and Buddhists on whether the self (ātman) exists. The Hindus, including Naiyāyikas and Mīmā?sakas, argue that recognition evidences the existence of the self, while Buddhist philosopher ?āntarak?ita maintains that there is no self and recognition should be explained in another way. This article examined two disputes, focusing on the two subsidiary aspects of a recognition: memory and self-recognition. For Hindus, it is the existence of the self that makes memory and self-recognition possible. For Buddhists, it is due to the phenomena of memories and self-recognitions that people postulate the existence of the self. I argue that Buddhist explanation of memory is more acceptable, while their debates on self-recognition should be considered as a tie.  相似文献   
895.
We report a theoretical investigation on the control of wave-vector filtering (WVF) in a two-dimensional electron gas modulated by realistic magnetic barriers and δ-doping, which can be experimentally realised by depositing a ferromagnetic stripe on the surface of a GaAs/AlxGa1?xAs heterostructure and using atomic layer doping. Theoretical analysis demonstrates that a sizeable WVF effect still exists even if δ-doping is introduced into the device. Numerical calculation reveals that the WVF efficiency is related closely to the δ-doping. Thus, the WVF effect in a magnetic nanostructure can be conveniently manipulated by properly adjusting the weight and/or the position of the δ-doping, giving rise to a tunable momentum filter for nanoelectronics applications.  相似文献   
896.
On account of its good biocompatibility, superelastic Ni–Ti arc wire alloys have been successfully used in orthodontic clinics. Nevertheless, delayed fracture in the oral cavity caused by hydrogen diffusion can be observed. The in situ stress relaxation susceptibility of a Ni–Ti shape memory alloy towards hydrogen embrittlement has been examined with respect to the current densities and imposed deformations. Orthodontic wires have been relaxed at different martensite volume fractions using current densities of 5, 10 and 20 A/m2 at 20 °C. The in situ relaxation stress shows that, for an imposed strain at the middle of the austenite–martensite transformation, the specimen fractures at the martensite–austenite reverse transformation. However, for an imposed strain at the beginning of the austenite–martensite plateau, the stress decreases in a similar way to the full austenite structure. Moreover, the stress plateau has been recorded at the reverse transformation for a short period. For the fully martensite structure, embrittlement occurs at a higher stress value. This behaviour is attributed to the interaction between the in situ austenite phase expansion and the diffusion of hydrogen in the different volume fractions of the martensite phase, produced at an imposed strain.  相似文献   
897.
Background and objectives: Extreme cardiovascular reactions to psychological stress have been associated with traumatic life experiences. Previous studies have focused on the occurrence or frequency of abuse rather than type of abuse. We examined how occurrence, frequency, and the type of abuse history are related to cardiovascular reactivity (CVR) to acute psychological stress. Design: The study consisted of between group and continuous analyses to examine the association between occurrence, type, and frequency of abuse with cardiovascular reactions to acute psychological stress. Methods: Data from 64 participants were collected. Heart rate, systolic blood pressure, and diastolic blood pressure were measured at baseline and during a standard mental arithmetic stress task. Results: Individuals who experienced abuse showed diminished CVR to acute psychological stress; this was driven specifically by the history of sexual abuse. Frequency of abuse did not relate to stress reactions. Conclusions: These findings accord with previous work suggesting a relationship between traumatic life experience and hypoarousal in physiological reactivity and extend previous findings by suggesting the relationship may be driven by sexual abuse.  相似文献   
898.
To select appropriate fire protection options for buildings during their design stage, economic, safety, environmental, and societal criteria need to be accounted for. The divergent and sometimes conflictual desires from different fire design stakeholders involved in the process present a multicriteria decision problem. Design decision criteria and fire protection options can be interdependent, and so there is a need to manage these desires with an advanced decision analysis technique, thereby reducing uncertainties in the complex decision‐making process. The aim of this paper is to use the weighted/geometric mean method‐analytic network process (W/GMM‐ANP) to balance the opinions of fire design stakeholders extracted from 42 structured stakeholder interviews on selecting the most suitable fire protection option for buildings constructed of steel frames. Different categories of interdependent decision elements were developed from 22 design decision criteria and 5 proposed fire protection options to produce a network of decision clusters for multicriteria decision analysis. In the synthesis and ranking of fire protection options, the W/GMM‐ANP accounted for the multiple interdependencies of weighted and unweighted stakeholder desires and managed the complexity of the decision‐making problem. The technique is proposed for approaching suitable group decisions in structural fire design of steel‐framed buildings as well as other performance‐based engineering decision making that may involve multidisciplinary stakeholders.  相似文献   
899.
结合ERP技术、创伤电影范式和改进的工作记忆范式探讨了认知分心的强度对创伤性信息加工的影响。结果发现, (1)高负荷上的N2波幅显著大于低负荷上的。(2)在低工作记忆负荷上, 创伤负性图引发的LPP波幅显著大于创伤中性图和无关中性图; 而在高工作记忆负荷上, 三类图片引发的LPP波之间差异不再显著。(3)在创伤负性图上高、低负荷工作记忆任务诱发的LPP波差异显著, 且高负荷条件下的LPP波幅显著小于低负荷条件。结果表明, 相比低认知控制, 早期高认知控制对创伤性信息的调节更有效, 支持了认知控制理论。  相似文献   
900.
各种心理调查、心理实验中, 数据的缺失随处可见。由于数据缺失, 给概化理论分析非平衡数据的方差分量带来一系列问题。基于概化理论框架下, 运用Matlab 7.0软件, 自编程序模拟产生随机双面交叉设计p×i×r缺失数据, 比较和探讨公式法、REML法、拆分法和MCMC法在估计各个方差分量上的性能优劣。结果表明:(1) MCMC方法估计随机双面交叉设计p×i×r缺失数据方差分量, 较其它3种方法表现出更强的优势; (2) 题目和评分者是缺失数据方差分量估计重要的影响因素。  相似文献   
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