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451.
Background/Objective: Despite the fact that electronic cigarettes, or e-cigarettes, are being increasingly used as an alternative to smoking tobacco cigarettes, few studies have explored psychological factors associated with e-cigarette use. Prior studies aimed at exploring correlates of e-cigarette use have focused on sociodemographic and smoking-related characteristics. However, no previous work has examined psychological features such as impulsivity among e-cigarettes users. The main objective of this study was to compare impulsivity rates across four groups of participants: current e-cigarette users who were former smokers; current smokers; former smokers; and controls. Method: A sample of 136 participants completed a computerized delay discounting task for hypothetical monetary values. Results: Delay discounting was greater among e-cigarette users than former smokers. E-cigarette users also showed an intermediate discounting that did not differ from smokers and controls. Moreover, delay discounting was significantly greater among current smokers compared to former smokers and controls. Conclusions: Taken together, our results extend previous research on delay discounting by providing evidence on impulsivity levels among current e-cigarette users for the first time.  相似文献   
452.
The term perceptual bistability refers to all those conditions in which an observer looks at an ambiguous stimulus that can have two or more distinct but equally reliable interpretations. In this work, we investigate perception of Necker Cube in which bistability consists of the possibility to interpret the cube depth in two different ways. We manipulated the cube ambiguity by darkening one of the cube faces (cue) to provide a clear cube interpretation due to the occlusion depth index. When the position of the cue is stationary the cube perceived perspective is steady and driven by the cue position. However, when we alternated in time the cue position (i.e. we changed the position of the darkened cube face) two different perceptual phenomena occurred: for low frequencies the cube perspective alternated in line with the position of the cue; however for high frequencies the cue was no longer able to bias the perception but it appears as a floating feature traveling across the solid with the cube whole perspective that returns to be bistable as in the conventional, bias-free, case.  相似文献   
453.
The present study was aimed at assessing whether focusing attention on a task-relevant part of a word prevents processing of its meaning. Participants performed a color-naming task on a prime word followed by lexical decision on a probe. Primes were words, which could contain an embedded color word (e.g., “redemption”) written in an incongruent color. Probes were either semantically related (e.g., “confession”) or unrelated (e.g., “production”) to the prime word. A Stroop effect emerged for color words appearing either in the initial or in the final position of the carrier word. A priming effect also emerged, with faster responses to probes semantically related to the prime. These results are evidence that focusing attention on part of a prime (i.e., the embedded color word) does not prevent the semantic processing of the entire word.  相似文献   
454.
Interference with activity of numerous cerebral structures produces memory deficiencies; in many instances, however, when animals are over-trained such interference becomes innocuous. Systemic administration of protein synthesis inhibitors impairs long-term retention; this effect has been interpreted to mean that protein synthesis is required for memory consolidation, though little is known about the effect of protein synthesis inhibitors on memory of enhanced learning in the rat. To further analyze the protective effect of enhanced learning against amnesic treatments, groups of Wistar rats were trained in a one-trial step-through inhibitory avoidance task, using different intensities of foot-shock during training. Cycloheximide (CXM; 2.8 mg/kg), an inhibitor of protein synthesis, was injected either 30 min before training or immediately after training. Twenty-four hours after training retention latencies were recorded. Our data showed that both pre- and post-training administration of CXM produced amnesia in those groups that had been trained with relatively low foot-shock intensities, but no impairment in retention was observed when relatively high intensities of foot-shock were administered. These and similar results lead us to conclude that protein synthesis inhibitors may interfere with memory consolidation, but their effect disappears when animals are submitted to an enhanced learning experience, calling into question the idea that protein synthesis is required for memory consolidation.  相似文献   
455.
ABSTRACT— Aging is associated with preserved enhancement of emotional memory, as well as with age-related reductions in memory for negative stimuli, but the neural networks underlying such alterations are not clear. We used a subsequent-memory paradigm to identify brain activity predicting enhanced emotional memory in young and older adults. Activity in the amygdala predicted enhanced emotional memory, with subsequent-memory activity greater for negative stimuli than for neutral stimuli, across age groups, a finding consistent with an overall enhancement of emotional memory. However, older adults recruited greater activity in anterior regions and less activity in posterior regions in general for negative stimuli that were subsequently remembered. Functional connectivity of the amygdala with the rest of the brain was consistent with age-related reductions in memory for negative stimuli: Older adults showed decreased functional connectivity between the amygdala and the hippocampus, but increased functional connectivity between the amygdala and dorsolateral prefrontal cortices. These findings suggest that age-related differences in the enhancement of emotional memory might reflect decreased connectivity between the amygdala and typical subsequent-memory regions, as well as the engagement of regulatory processes that inhibit emotional responses.  相似文献   
456.
Roberto Cipriani   《Religion》2009,39(2):109-116
The breakdown of European society is changing rapidly, particularly in the field of religion. Culture is of vital importance to the presence of religion in all nations. Religions also have exerted a certain degree of political power, thus influencing the economy and other related spheres of life.The different religions in Europe exhibit a variety of attitudes towards religious pluralism. The religious differences between Western and Eastern Europe depend mainly on issues of national identity related to religious adherence.This essay provides an overview of religion and politics, or Church and state, in Europe. It will conclude with some reflections about possible future developments within religious traditions in Europe. New religious communities and religious organisations are reaching different parts of Europe, sometimes very far from their place of origin. Christianity (Catholicism, Orthodoxy, and Protestantism) is the most widespread religion in contemporary Europe. Catholic religion is well diffused in Europe, but there are substantial differences in belief, behaviour and practice within different Catholic communities. There are various branches of Orthodoxy in Europe, such as the distinct autocephalous churches. In general Orthodox religion is closely aligned with national culture. Islam is also present in Western countries, and its impact is evident.  相似文献   
457.
458.
In the last decade, changes in the structure of intelligence across the life-span has become a central topic in the research on human intelligence. One of the main hypotheses that has arisen to account for such changes has been the age de-differentiation hypothesis [Balinsky, Genetic Psychology Monographs 23 1941, 191]. It predicts an increase in the importance of g, and a decrease in the number and importance of the lower-order abilities from early maturity to senescence. Despite of the research effort to test this hypothesis, no study has ever been conducted controlling by sex. For that purpose, males and females of the Spanish standardisation sample of the WAIS-III were analysed separately. Results show that the importance of g does not change with age irrespective of sex. Thus, the age de-differentiation hypothesis is rejected for both males and females. The indifferentiation hypothesis is supported as a more appropriate view of the changes in the structure of intelligence across adulthood.  相似文献   
459.
Transforming the core array in Tucker three-way component analysis to simplicity is an intriguing way of revealing structures in between standard Tucker three-way PCA, where the core array is unconstrained, and CANDECOMP/PARAFAC, where the core array has a generalized diagonal form. For certain classes of arrays, transformations to simplicity, that is, transformations that produce a large number of zeros, can be obtained explicitly by solving sets of linear equations. The present paper extends these results. First, a method is offered to simplifyJ ×J × 2 arrays. Next, it is shown that the transformation that simplifies anI ×J ×K array can be used to also simplify the (complementary) arrays of order (JKI) ×J ×K, of orderI × (IKJ) ×K and of orderI ×J × (IJK). Finally, the question of what constitutes the maximal simplicity for arrays (the maximal number of zero elements) will be considered. It is shown that cases of extreme simplicity, considered in the past, are, in fact, cases of maximal simplicity.  相似文献   
460.
Although the functional aspects of synchronization of the circadian pacemaker by environmental light have been extensively studied, few studies have provided systematic information about the temporal organization of behavior under light-dark cycles with varying proportions of light and darkness. In the present study, the running-wheel activity profiles of mice were investigated under short, medium, and long photoperiods. The results clearly indicated that the temporal distribution of locomotor activity in mice is modulated by photoperiod. The activity profile was compressed under long photoperiods and expanded under short photoperiods. Although negative masking by light and alterations in the state of dark adaptation may have partially accounted for the phenomenon, the major mechanism seemed to be a compression and expansion of the circadian pacemaker's cycle, as expressed in the compression and expansion of the photic phase-response curve.  相似文献   
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