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1.
Research on classical conditioning with drug unconditional stimuli has had a profound effect on the understanding of general conditioning processes. The experiment reported by R. V. McDonald and S. Siegel (see record 2004-10475-001) demonstrates that cues coincident with the onset of an event can become associated with the rest of the event. This sort of learning is probably ubiquitous and has been proposed as a mechanism behind the development of panic disorder, in which interoceptive cues coincident with the start of a panic attack can be associated with the rest of the attack and can eventually come to elicit full-blown panic on their own. Evidence that extinction exposure to early onset cues can reduce their power is especially important. Drug conditioning research continues to provide a powerful testing ground for important general principles of learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Two experiments examined how cross-list directional associations influenced list-method directed forgetting and the degree of interference observed on each list. Each List 1 item had a (a) bidirectionally related item on List 2 (chip ←→ potato), (b) forward association with an item on List 2 (chip → wood), (c) backward association from an item on List 2 (chip ← chisel), or (d) no relationship with List 2 items. The results revealed that associative relationships that eliminated retroactive interference in the baseline condition also eliminated the directed forgetting costs. In contrast, associative relationships did not affect List 2 recall in the forget group, which remained unchanged across experimental conditions. However, certain conditions reduced proactive interference in the remember group, thereby eliminating the benefits of directed forgetting. The directed forgetting costs and benefits were observed independently of each other. The authors propose that these effects emerged from a combination of item and context strengthening induced by different associative directions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Previous research has shown that under certain conditions environmental cues associated with morphine administration induce drug-opposite conditioned effects that mimic symptoms of opiate withdrawal. R. V. McDonald and S. Siegel (see record 2004-10475-001) extend these observations by demonstrating that acute exposure to a low dose of morphine induces symptoms of opiate withdrawal in rats previously exposed to a high dose of morphine. They hypothesized that early drug onset cues, repeatedly paired with later, larger drug effects, mediate the paradoxical effect of the low drug dose on behavior. They also hypothesized that conditioned withdrawal symptoms induced by the early drug onset cues may mediate the "priming" effect of drugs on relapse and craving. The authors of this comment discuss the degree to which the literature supports this hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
当前,丁克家庭逐渐为越来越多的人们所接受,并成为一种时尚。从伦理道德的层面考察,丁克现象有其可通约的一面,但由于其伦理实质是以自由为目标,以自我为中心的自私性质的价值追求,因此,它不是也不应该是文化的普适化选择。  相似文献   
5.
R. V. McDonald and S. Siegel (see record 2004-10475-001) present new evidence for the idea that opioid drug-opposite responses can become conditioned to cues of initial drug onset and that they could, therefore, play a role in the development of tolerance of some drug effects and a role in the elicitation of withdrawal-like symptoms in cases in which addicted individuals are exposed to small doses of the drug they normally consume. In this comment, some puzzling features of the data are discussed, and alternative explanations are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
State psychological associations can respond to supply and demand problems for postdoctoral residencies and internships by creating statewide training programs. A state psychological association training model is presented. The Arizona Psychological Association (AzPA) created a nonprofit subsidiary corporation- the Arizona Psychology Training Consortium-to increase the number of high-quality training opportunities in Arizona. The structure and operation of the program are described. The training model emphasizes cultural diversity, psychotherapy, and independent practice. Members of the practice community in Arizona serve as supervisors, trainers, and mentors. From 2001 through 2006, 19 postdoctoral residents and 51 interns completed the program. AzPA has benefited from increased student involvement. Many residents and interns later became association members. Arizona can serve as a model for other states that wish to help their professionals in training. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
新建工科院校学生专业社团,没有高年级学生的传帮带,没有良好的科学研究氛围,各方面均属于探索阶段,为了引导专业学生社团健康持续发展,使之发挥更好的素质教育作用,对大学生专业社团设立导师制是一种行之有效的途径。  相似文献   
8.
Workers in grocery stores are exposed to numerous musculoskeletal risks that can be reduced using assistive devices while performing stocking tasks. A regional grocery store has recently deployed a mobile cart without comprehension of its ergonomic impact on workers, which this article investigates using normalized electromyography data (%MVC). This article studies not only ergonomic impact based on %MVC values but also work performance represented by a muscle force metric (MFM). The results from this study showed highest muscle groups in %MVC and MFM were the erector spinae and triceps. Interestingly, muscle activations on erector spinae were reduced when mobile cart is used. %MVC and MFM distribution for value‐added‐ and non‐value‐added subtasks were slightly different, with larger differences observed for non‐value‐added tasks. Video recordings revealed higher work performance when the mobile cart is used. In future research, the number of participants will be increased to further validate the results from this study.  相似文献   
9.
针对高考志愿填报录取最优化、最佳匹配问题,提出了基于遗传算法搜索最优解的解决方案。该方案模拟物种自然选择和遗传进化过程,将不同考生的高考志愿按录取结果利益最大化进行排序。在可选择院校数量相同的情况下,对不同考生考试成绩的数据通过程序不断进行智能优化和迭代,志愿排序结果趋于稳定,且达到最佳匹配。其不但满足考生的实际需求,而且达到志愿填报利益最大化的目的。该方法采用涵盖985、211、普通院校的10所高校的实际数据进行测试,结果表明,遗传算法可以用来求解最优高考志愿填报排序问题,且具有很高的准确率和适应度。  相似文献   
10.
In this paper we propose a connectionist model for variable binding. The model is topology dependent on the graph it builds based on the predicates available. The irregular connections between perceptron-like assemblies facilitate forward and backward chaining. The model treats the symbolic data as a sequence and represents the training set as a partially connected network using basic set and graph theory to form the internal representation. Inference is achieved by opportunistic reasoning via the bidirectional connections. Consequently, such activity stabilizes to a multigraph. This multigraph is composed of isomorphic subgraphs which all represent solutions to the query made. Such a model has a number of advantages over other methods in that irrelevant connections are avoided by superimposing positionally dependent sub-structures that are identical, variable binding can be encoded and multiple solutions can be extracted simultaneously. The model also has the ability to adapt its existing architecture when presented with new clauses and therefore add new relationships/rules to the model explicitly; this is done by some partial retraining of the network due to the superimposition properties.  相似文献   
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