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81.
Functional neuroimaging suggests that limbic regions of the medial frontal cortex may be abnormally active in individuals with depression. These regions, including the anterior cingulate cortex, are engaged in both action regulation, such as monitoring errors and conflict, and affect regulation, such as responding to pain. The authors examined whether clinically depressed subjects would show abnormal sensitivity of frontolimbic networks as they evaluated negative feedback. Depressed subjects and matched control subjects performed a video game in the laboratory as a 256-channel EEG was recorded. Speed of performance on each trial was graded with a feedback signal of A, C, or F. By 350 ms after the feedback signal, depressed subjects showed a larger medial frontal negativity for all feedback compared with control subjects with a particularly striking response to the F grade. This response was strongest for moderately depressed subjects and was attenuated for subjects who were more severely depressed. Localization analyses suggested that negative feedback engaged sources in the anterior cingulate and insular cortices. These results suggest that moderate depression may sensitize limbic networks to respond strongly to aversive events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
介绍了2002年我国力车胎的行业现状。近年的发展及展望。并着重描述了力车胎专用设备的新发展。  相似文献   
83.
This is an outline of research in neural networks for feedback control done since the mid 1990s at the Automation and Robotics Research Institute (ARRI) of The University of Texas at Arlington (UTA). It shows how the developments of Intelligent Control Systems based on neural networks have followed three main generations. This statement provides a short, broad-brush perspective on the development of intelligent neural feedback controllers.  相似文献   
84.
定电流对LED的重要性   总被引:2,自引:0,他引:2  
高功率超高亮度LED已经开始大量应用.要实际体现LED(尤其是高功率超高亮度LED)的优点,采用定电流驱动方式必要条件之一.  相似文献   
85.
在详细分析料坯在水箱内冷却热过程特点的基础上,提出了前馈和反馈相结合的水流量优化控制策略,并将该策略应用于宝钢线材厂控冷轧线上。实际运行结果表明:该策略能够合理地控制水箱水流量,从而保证了线材水箱出口处的温度满足工艺要求,大大提高了线材成品的质量。所做工作对国内同类企业有重要的意义。  相似文献   
86.
The long-term effects of the Cognitive Adaptation Theory Index (CATI) on psychological and physical health outcomes among men (n=199) and women (n=99) treated for coronary artery disease with percutaneous transluminal coronary angioplasty were examined. The CATI reflects a positive view of the self, a positive view of one's future, and a sense of personal control over daily life. This index was created from questionnaires administered during hospitalization for the initial angioplasty. Four years later, the CATI predicted positive adjustment to disease, even when initial adjustment was taken into consideration. In addition, the CATI predicted a reduced likelihood of sustaining a subsequent cardiac event over 4 yrs. This association was more robust for men. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
Although increasing feedback specificity is generally beneficial for immediate performance, it can undermine certain aspects of the learning needed for later, more independent performance. The results of the present transfer experiment demonstrate that the effects of increasing feedback specificity on learning depended on what was to be learned, and these effects were partially mediated through the opportunities to learn how to respond to different task conditions during practice. More specific feedback was beneficial for learning how to respond to good performance and detrimental for learning how to respond to poor performance. The former relationship was partially mediated by feedback specificity's effect on learning opportunities during practice. The results have implications for designing feedback interventions and training to maximize the learning of various aspects of a task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
Previous studies have found that in American culture high-arousal positive states (HAP) such as excitement are valued more and low-arousal positive states (LAP) such as calm are valued less than they are in Chinese culture. What specific factors account for these differences? The authors predicted that when people and cultures aimed to influence others (i.e., assert personal needs and change others' behaviors to meet those needs), they would value HAP more and LAP less than when they aimed to adjust to others (i.e., suppress personal needs and change their own behaviors to meet others' needs). They test these predictions in 1 survey and 3 experimental studies. The findings suggest that within and across American and Chinese contexts, differences in ideal affect are due to specific interpersonal goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
The authors examined whether participants can shift their criterion for recognition decisions in response to the probability that an item was previously studied. Participants in 3 experiments were given recognition tests in which the probability that an item was studied was correlated with its location during the test. Results from all 3 experiments indicated that participants' response criteria were sensitive to the probability that an item was previously studied and that shifts in criterion were robust. In addition, awareness of the bases for criterion shifts and feedback on performance were key factors contributing to the observed shifts in decision criteria. These data suggest that decision processes can operate in a dynamic fashion, shifting from item to item. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
真丝纬编织物的品种开发   总被引:1,自引:0,他引:1  
真丝针织物的品种花色单调已严重影响和制约其扩大出口创汇及生产企业的经济效益及发展。认为主要是品种开发与市场需求脱节,未能掌握国际市场导向指导消费,以及生产技术素质和管理能力不足。文章提出了开发真丝纬编织物的基本原则和目前可行的开发品种。  相似文献   
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