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971.
Episodic memory and the hippocampus: it's about time   总被引:2,自引:0,他引:2  
Several recent studies have sought to develop animal models of episodic memory, the capacity to recollect unique personal experiences. However, these studies have not yet provided unambiguous evidence that this capacity is based on recollection of the learning episodes. A recent study that examined memory for the ordering of events within unique experiences, and demonstrated a critical and selective role for the hippocampus, suggests a new and promising model for neurobiological analyses of episodic memory.  相似文献   
972.
Anticipating the future has a decided evolutionary advantage, and researchers have found many evolutionarily conserved mechanisms by which humans and animals learn to predict future events. Researchers often study such learned behavior using conditioning experiments. The marine snail Aplysia has been at the forefront of research into the cellular and molecular mechanisms of classical conditioning. Recently, Aplysia has also gained a reputation as a valuable model system for operant reward learning. Its feeding behavior can be operantly conditioned in the intact animal as well as in reduced preparations of the nervous system. The reward signal relies on dopamine transmission and acts in conjunction with activity in an identified neuron (B51) to bring about operant memory.  相似文献   
973.
The simplicity principle in human concept learning   总被引:1,自引:0,他引:1  
How do we learn concepts and categories from examples? Part of the answer might be that we induce the simplest category consistent with a given set of example objects. This seemingly obvious idea, akin to simplicity principles in many fields, plays surprisingly little role in contemporary theories of concept learning, which are mostly based on the storage of exemplars, and avoid summarization or overt abstraction of any kind. This article reviews some evidence that complexity minimization does indeed play a central role in human concept learning. The chief finding is that subjects' ability to learn concepts depends heavily on the concepts' intrinsic complexity; more complex concepts are more difficult to learn. This pervasive effect suggests, contrary to exemplar theories, that concept learning critically involves the extraction of a simplified or abstracted generalization from examples.  相似文献   
974.
支持型领导行为在工作压力模型中的作用机制研究   总被引:1,自引:0,他引:1  
本研究调查了 1 3个企业共 2 1 8位员工 ,探讨了支持型领导行为在角色冲突、人际冲突、缺乏成就与发展 (压力源 )和工作满意感、工作焦虑 (压力反应 )之间的作用机制。研究发现 :(1 )支持型领导行为对工作满意感和工作焦虑有主效应 ,但是由于逆向缓冲的存在 ,支持型领导行为的主效应并不总是对的 ,我们必须在更大的范围中考虑领导行为的效应 ;(2 )缓冲效应的六个假设只有一个被证明 ,但是方向相反 ,即支持型领导行为加剧了由人际冲突造成的工作不满意感 ;(3)两个中介模型的部分关系被证明 ,但是我们很难确定是支持型领导行为的弱化效应还是评价作用。为了更好地说明因果关系 ,在将来的研究中纵向研究设计被认为更为恰当。  相似文献   
975.
Erna was one of the child patients treated by Melanie Klein in Berlin, employing her recently discovered play technique. Since Erna died in Chile, the authors considered the IPA Congress in Santiago an opportunity to present a paper as a homage both to Erna and, especially, to Klein. She learned much from that very disturbed child, which she later used to sustain the ongoing development of her theories. The paper explores biographic data relevant to understanding both the case and the theories. It analyses the case material to follow Klein in the discovery and the handling of the child's transference and the harsh expressions of hate, jealousy and envy, which are brought in, with sad consequences, by strong persecutory feelings. Klein's comparison of this case with that of Freud's Wolf-man is also considered, mostly to show that the similarities were less than originally claimed, and that Klein, perhaps, was introducing a theoretic shift which led her technique to gradually change from ' Nachträglichkeit ' to the 'signification-resignification' pair, akin to Strachey's concept of the mutative interpretation. Lastly, the comprehension of Erna's strong psychotic traits and the links with later developments of the theory on psychosis are studied.  相似文献   
976.
Archival studies of within-family prosocial behavior (Judge & Hrdy, 1992; Smith, Kish, & Crawford, 1987) have shown that inheritance patterns support Hamilton’s (1964) theory of inclusive fitness, such that people will more of their estates to relatives of closer genetic relatedness. In a survey-based simulation of these studies, students allocated one of three lotteries to their blood relatives. As expected, participants allocated greater proportions of their lotteries to relatives of greater genetic relatedness. This effect became stronger with decreasing lottery amounts. Relatives of certain relatedness were favored over relatives of uncertain relatedness (via paternal uncertainty), and this effect was stronger among those with less money to allocate. Male participants tended to favor their young female relatives over their young male relatives when given the smallest lottery, but this sex preference reversed when male participants were given the largest lottery. In general, scarcer resources led to more evolutionarily conservative investment strategies.  相似文献   
977.
978.
We examined the relationship between executive functions and both factual and conceptual learning of science, specifically chemistry, in early adolescence. Sixty‐three pupils in their second year of secondary school (aged 12–13 years) participated. Pupils completed tasks of working memory (Spatial Working Memory), inhibition (Stop‐Signal), attention set‐shifting (ID/ED), and planning (Stockings of Cambridge), from the CANTAB. They also participated in a chemistry teaching session, practical, and assessment on the topic of acids and alkalis designed specifically for this study. Executive function data were related to (1) the chemistry assessment which included aspects of factual and conceptual learning and (2) a recent school science exam. Correlational analyses between executive functions and both the chemistry assessment and science grades revealed that science achievements were significantly correlated with working memory. Linear regression analysis revealed that visuospatial working memory ability was predictive of chemistry performance. Interestingly, this relationship was observed solely in relation to the conceptual learning condition of the assessment highlighting the role of executive functions in understanding and applying knowledge about what is learned within science teaching.  相似文献   
979.
Financial ratio plays a crucial role in business performance prediction, but the ability of the decision maker to use this method in adjusting management strategy has been extensively ignored. In this paper we attempt to build a fuzzy chance constrained least squares twin support vector machine (FCC-LSTSVM) to predict the business performance through the financial ratios. Specifically, machine learning techniques are utilized to build the models and 796 listed companies in China are selected as the data set. We find that different efficiencies are performed for different models with the same industry and different effectiveness are shown for different predicting time periods with the same method. In addition, the predicting achievements of business performance depend on the types of industries. This paper has extent significance both in theoretical development and managerial practices.  相似文献   
980.
Syntactic priming in language production is the increased likelihood of using a recently encountered syntactic structure. In this paper, we examine two theories of why speakers can be primed: error‐driven learning accounts (Bock, Dell, Chang, & Onishi, 2007; Chang, Dell, & Bock, 2006) and activation‐based accounts (Pickering & Branigan, 1999; Reitter, Keller, & Moore, 2011). Both theories predict that speakers should be primed by the syntactic choices of others, but only activation‐based accounts predict that speakers should be able to prime themselves. Here we test whether speakers can be primed by their own productions in three behavioral experiments and find evidence of structural persistence following both comprehension and speakers’ own productions. We also find that comprehension‐based priming effects are larger for rarer syntactic structures than for more common ones, which is most consistent with error‐driven accounts. Because neither error‐driven accounts nor activation‐based accounts fully explain the data, we propose a hybrid model.  相似文献   
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