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971.
马克思与虚无主义问题   总被引:1,自引:0,他引:1  
马克思的目的是要说明人对价值的需要无须超越历史就能得到满足。认为善(good)内在于历史上与断言善是与历史相同的并非一回事。马克思并不是一个历史主义者——如罗森所使用的术语——因为他没有把善与"所发生之事"等同起来。罗森认为,马克思必定主张在历史中发生的任何事情都是可允许的。马克思的标准是人,而不是历史中在马克思的特定意义上算作人类的(行动)的所有行动。实际上在历史进程中,绝大多数个体是以一种非人的方式把自己对象化的。这就是马克思把前共产主义时期描述为"前历史"的原因,因为那是这样一段时间,在其中社会存在是人类活动的无意识的产物。只有当诸个体自觉地决定其生活并把物质世界置于合作性控制之下,恰当意义上的历史才真正开始。  相似文献   
972.
In a series of four experiments, we examine the hypothesis that selective attention is crucial for the generation of conscious knowledge of contingency information. We investigated this question using a spatial priming task in which participants were required to localize a target letter in a probe display. In Experiment 1, participants kept track of the frequency with which the predictive letter in the prime appeared in various locations. This manipulation had a negligible impact on contingency awareness. Subsequent experiments requiring participants to attend to features (color, location) of the predictive letter increased contingency awareness somewhat, but there remained a large proportion of individuals who remained unaware of the strong contingency. Together the results of our experiments suggest that the construct of attention does not fully capture the processes that lead to contingency awareness, and suggest a critical role for bottom-up feature integration in explicit contingency learning.  相似文献   
973.
Brain imaging studies suggest that truth telling constitutes the default of the human brain and that lying involves intentional suppression of the predominant truth response. By manipulating the truth proportion in the Sheffield lie test, we investigated whether the dominance of the truth response is malleable. Results showed that frequent truth telling made lying more difficult, and that frequent lying made lying easier. These results implicate that (1) the accuracy of lie detection tests may be improved by increasing the dominance of the truth response and that (2) habitual lying makes the lie response more dominant.  相似文献   
974.
The purpose of this study was to investigate whether patients with multiple sclerosis (MS) and their partners show adversarial growth and to examine which psychological and disability variables contribute to this in patients and their partners. The study also investigated the relationship between growth and distress. Seventy-two patients with MS and their partners provided demographic information and completed measures of posttraumatic growth, illness perceptions, depression, cognitive function and disability. Both patients and partners showed adversarial growth, with patients reporting significantly higher growth than partners. The only significant predictor for patient growth was partner growth, and vice versa. Dissimilarity in illness representations between patients and their partners on the consequences of MS dimension, patient mood and patient growth accounted for significant variance in partner growth. The findings support the idea of a ‘communal search for meaning’ where patients and their partners experience the trauma of having a chronic illness and subsequently find positive aspects together.  相似文献   
975.
Pediatric gastrointestinal disorders are commonly experienced by youth and have been shown to be associated with increased rates of psychosocial difficulties. Aim of the current study was to extend development of the Pediatric Symptom Checklist (PSC), a brief parent-completed measure designed to assess children’s behavioral and emotional functioning, by examining its factor structure in a pediatric gastroenterology sample. Parents of 176 children ages 4–16 years visiting a pediatric gastroenterologist completed the PSC. The factor structure of the PSC was examined using principal component analysis. Parallel analysis was utilized to determine the number of factors to retain and indicated that three factors existed within the data. A principal component analysis with varimax rotation identified factors measuring internalizing, externalizing, and attention difficulties. The three factors that emerged on the PSC provide initial support for the utility of the PSC in pediatric gastroenterology clinics.  相似文献   
976.
The way in which we respond to everyday stressors can have a profound impact on cognitive functioning. Maladaptive stress responses in particular are generally associated with impaired cognitive performance. We argue, however, that the cognitive system mediating task performance is also a critical determinant of the stress-cognition relationship. Consistent with this prediction, we observed that stress reactivity consistent with a maladaptive, threat response differentially predicted performance on two categorization tasks. Increased threat reactivity predicted enhanced performance on an information-integration task (i.e., learning is thought to depend upon a procedural-based memory system), and a (nonsignificant) trend for impaired performance on a rule-based task (i.e., learning is thought to depend upon a hypothesis-testing system). These data suggest that it is critical to consider both variability in the stress response and variability in the cognitive system mediating task performance in order to fully understand the stress-cognition relationship.  相似文献   
977.
Drosophila larvae combine a numerically simple brain, a correspondingly moderate behavioral complexity, and the availability of a rich toolbox for transgenic manipulation. This makes them attractive as a study case when trying to achieve a circuit-level understanding of behavior organization. From a series of behavioral experiments, we suggest a circuitry of chemosensory processing, odor-tastant memory trace formation, and the "decision" process to behaviorally express these memory traces--or not. The model incorporates statements about the neuronal organization of innate vs. conditioned chemosensory behavior, and the types of interaction between olfactory and gustatory pathways during the establishment as well as the behavioral expression of odor-tastant memory traces. It in particular suggests that innate olfactory behavior is responsive in nature, whereas conditioned olfactory behavior is captured better when seen as an action in pursuit of its outcome. It incorporates the available neuroanatomical and behavioral data and thus should be useful as scaffold for the ongoing investigations of the chemo-behavioral system in larval Drosophila.  相似文献   
978.
5-bromo-2-deoxyuridine (BrdU) is often used in studies of adult neurogenesis and olfactory learning, but it can also have toxic effects on highly proliferative tissue. We found that pairing Kool-Aid flavors with acute systemic injections of BrdU induced strong conditioned flavor aversions. Intermittent injections during Kool-Aid-glucose conditioning interfered with learning of a conditioned flavor-nutrient preference. Acute injection of BrdU also elevated plasma corticosterone levels and induced c-Fos in the visceral neuraxis. Thus, acute or intermittent systemic injections of BrdU (50-200 mg/kg) have aversive effects that may interfere with learning.  相似文献   
979.
It has been suggested that hyperglycemia and insulin resistance triggered by energy-dense diets can account for hippocampal damage and deficits of cognitive behaviour. We wonder if the impairment of learning and memory processes detected in diet-induced obese (DIO) mice is linked to diet composition itself. With this purpose we have evaluated learning performance in mice undergoing a short-term high-fat (HF) treatment, which leads to a pre-obese state characterized by increased adiposity without significant changes of glucose and insulin plasma levels. C57BL/6J mice were fed either a HF (45 kcal% from fat) or control diet (10 kcal% from fat) during 8 weeks. Learning performance was evaluated by using the four-arm baited version of the eight-arm radial maze test (RAM). Mice were trained to learn the RAM protocol and then memory was tested at different time-points. Time spent to consume food placed in baited arms and errors committed to find them were measured in all sessions. DIO mice significantly spent more time in learning the task and made a greater number of errors than controls. Moreover, retention tests revealed that both working and total memory errors were also more numerous in DIO mice. The current results show that short-term DIO impairs spatial learning and suggest that impairment of hippocampal learning elicited by HF diets might be perceptible before metabolic alterations linked to obesity develop.  相似文献   
980.
When trained to peck a selected position in a sagittally-oriented series of identical food containers, and then required to generalize to an identical series rotated by 90°, chicks identify as correct only the target position from the left end, while choosing the right one at chance. Here we show that when accustomed to systematic changes in inter-elements distances during training or faced with similar spatial changes at test, chicks identify as correct both the target positions from left and right ends. However, ordinal position is spontaneously encoded even when inter-element distances are kept fixed during training (in spite of the fact that distances between elements suffice for target identification without any numerical computation). We explain these findings in terms of intra-hemispheric coupling of bilateral numerical (ordinal) representation and unilateral (right hemispheric) spatial representation of the number line, producing differential allocation of attention in the left and right visual hemifields.  相似文献   
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