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191.
The life and career of the Soviet scholar of myth and religion Izrail′ Grigor′evič Frank-Kamenetskij is discussed, tracing his development from a scholar working exclusively on semitology to a theorist of myth and literature. The scholar’s relationship to German philosophy and Biblical scholarship is outlined, along with his relationship to Soviet scholarship of the 1920s and 1930s. The development of the scholar’s work is related to his encounter with N. Ja. Marr in the early 1920s, and the way in which Marr’s doctrine underwent considerable revisions when subjected to German philosophy and applied to narrative material is detailed. Finally the way in which attention increasingly turned to the genesis of literary plots and poetic metaphor is discussed, along with both the influence such work exerted and the enduring value of such work today.  相似文献   
192.
The goal of the present study was to elucidate the role of the human striatum in learning via reward and punishment during an associative learning task. Previous studies have identified the striatum as a critical component in the neural circuitry of reward-related learning. It remains unclear, however, under what task conditions, and to what extent, the striatum is modulated by punishment during an instrumental learning task. Using high-resolution functional magnetic resonance imaging (fMRI) during a reward- and punishment-based probabilistic associative learning task, we observed activity in the ventral putamen for stimuli learned via reward regardless of whether participants were correct or incorrect (i.e., outcome). In contrast, activity in the dorsal caudate was modulated by trials that received feedback--either correct reward or incorrect punishment trials. We also identified an anterior/posterior dissociation reflecting reward and punishment prediction error estimates. Additionally, differences in patterns of activity that correlated with the amount of training were identified along the anterior/posterior axis of the striatum. We suggest that unique subregions of the striatum--separated along both a dorsal/ventral and anterior/posterior axis--differentially participate in the learning of associations through reward and punishment.  相似文献   
193.
BackgroundThe pharmacology of traumatic memory extinction has not been fully characterized despite its potential as a therapeutic target for established, acquired anxiety disorders, including post-traumatic stress disorder (PTSD). Here we examine the role of endogenous glucocorticoids in traumatic memory extinction.MethodsMale C57BL/6J mice were injected with corticosterone (10 mg/kg, i.p.) or metyrapone (50 mg/kg, s.c.) during re-activation of a contextual fear memory, and compared to vehicle groups (N = 10–12 per group). To ensure that metyrapone was blocking corticosterone synthesis, we measured corticosterone levels following re-activation of a fear memory in metyrapone- and vehicle-treated animals.ResultsCorticosterone administration following extinction trials caused a long-lasting inhibition of the original fear memory trace. In contrast, blockade of corticosteroid synthesis with metyrapone prior to extinction trials enhanced retrieval and prevented extinction of context-dependent fear responses in mice. Further behavioral analysis suggested that the metyrapone enhancement of retrieval and prevention of extinction were not due to non-specific alterations in locomotor or anxiety-like behavior. In addition, the inhibition of extinction by metyrapone was rescued by exogenous administration of corticosterone following extinction trials. Finally, we confirmed that the rise in corticosterone during re-activation of a contextual fear memory was blocked by metyrapone.ConclusionsWe demonstrate that extinction of a classical contextual fear memory is dependent on endogenous glucocorticoid synthesis during re-activation of a fear memory. Our data suggest that decreased glucocorticoids during fear memory re-activation may contribute to the inability to extinguish a fear memory, thus contributing to one of the core symptoms of PTSD.  相似文献   
194.
195.
Economists define risk in terms of the variability of possible outcomes, whereas clinicians and laypeople generally view risk as exposure to possible loss or harm. Neuroeconomic studies using relatively simple behavioral tasks have identified a network of brain regions that respond to economic risk, but these studies have had limited success predicting naturalistic risk-taking. By contrast, more complex behavioral tasks developed by clinicians (e.g. Balloon Analogue Risk Task and Iowa Gambling Task) correlate with naturalistic risk-taking but resist decomposition into distinct cognitive constructs. We propose here that to bridge this gap and better understand neural substrates of naturalistic risk-taking, new tasks are needed that: are decomposable into basic cognitive and/or economic constructs; predict naturalistic risk-taking; and engender dynamic, affective engagement.  相似文献   
196.
Prospective memory (PM) among older adults has been shown to be influenced by frontal lobe (FL) function. An implementation intention (e.g., 'if situation X occurs, I will do Y') is a mnemonic strategy that may be particularly beneficial for individuals with low-FL function, as it has been suggested that implementation intentions produce heightened accessibility to environmental cues, and automatic triggering of previously formed intentions. The present study investigated the effectiveness of implementation intentions among 32 older adults characterized as possessing high- or low-FL function. Participants were placed into one of two conditions: Read-Only or Implementation Intentions, before being tested on a laboratory prospective memory task. Results indicated that older adults with high-FL composite scores demonstrated better PM than those with low-FL scores, and that those who made implementation intentions outperformed those who simply read task instructions. Of particular interest is the finding that high-FL participants benefited from implementation intentions, suggesting that implementation intentions may improve PM of all older adults regardless of FL function. Theoretical underpinnings of implementation intentions are discussed in the context of FL function.  相似文献   
197.
Happiness is a key ingredient of well-being. It is thus reasonable to expect that valuing happiness will have beneficial outcomes. We argue that this may not always be the case. Instead, valuing happiness could be self-defeating, because the more people value happiness, the more likely they will feel disappointed. This should apply particularly in positive situations, in which people have every reason to be happy. Two studies support this hypothesis. In Study 1, female participants who valued happiness more (vs. less) reported lower happiness when under conditions of low, but not high, life stress. In Study 2, compared to a control group, female participants who were experimentally induced to value happiness reacted less positively to a happy, but not a sad, emotion induction. This effect was mediated by participants' disappointment at their own feelings. Paradoxically, therefore, valuing happiness may lead people to be less happy just when happiness is within reach.  相似文献   
198.
Although proposed by bioecological models, there has been minimal empirical examination of whether children's individual differences moderate neighborhood effects on development. We used an urban community sample (8-12 years, N = 316) to examine interactions among neighborhood characteristics (problems and social organization) and children's temperament (fear, irritability and impulsivity) in predicting psychosocial adjustment. The main effects of neighborhood and temperament on outcomes were consistent with previous research. Findings show that development is challenging in disadvantaged neighborhoods whatever one's temperament, however, some effects of neighborhood were conditioned by temperament, particularly children's fear and irritability. Neighborhood problems were more strongly related to lower social competence for fearful and for less irritable children. Neighborhood problems were more strongly related to higher internalizing problems for low-fear children. Neighborhood social organization was more strongly related to greater social competence for low-fear children. Findings are discussed in relation to "diathesis-stress" and "differential responsiveness" models of temperament.  相似文献   
199.
Although worry is central to the diagnosis of generalized anxiety disorder (GAD), it is also commonly observed in other anxiety disorders. In this meta-analytic review, we empirically evaluated the extent to which worry is specific to GAD relative to patients with other anxiety disorders, those with other psychiatric disorders, and nonpsychiatric controls. A total of 47 published studies (N = 8,410) were included in the analysis. The results yielded a large effect size indicating greater severity/frequency of worry, meta-worry, and domains of worry among anxiety disorder patients v. nonpsychiatric controls (d = 1.64). In contrast to the many differences emerging from comparisons between anxiety disordered patients and nonpsychiatric controls, when anxiety disordered patients were compared to people with other psychiatric disorders they differed only on severity/frequency and not on meta-worry or domains of worry. A large effect size indicating greater severity/frequency of worry, meta-worry, and domains of worry among patients with GAD v. nonpsychiatric controls was also found (d = 2.05). However, differences between GAD and those with other psychiatric disorders also emerged for severity/frequency of worry. GAD was associated with greater worry difficulties than other anxiety disorders, which generally did not differ from those with other psychiatric disorders and each other. The implications of these findings for conceptualizing worry in GAD and other anxiety disorders, and the potentially moderating effects of age and gender are discussed.  相似文献   
200.
William Craig 《Synthese》2008,164(3):321-332
A common aim of elimination problems for languages of logic is to express the entire content of a set of formulas of the language, or a certain part of it, in a way that is more elementary or more informative. We want to bring out that as the languages for logic grew in expressive power and, at the same time, our knowledge of their expressive limitations also grew, elimination problems in logic underwent some change. For languages other than that for monadic second-order logic, there remain important open problems.  相似文献   
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