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91.
    
Dissociating motoric and motivational effects of pharmacological manipulations on operant behavior is a substantial challenge. To address this problem, we applied a response‐bout analysis to data from rats trained to lever press for sucrose on variable‐interval (VI) schedules of reinforcement. Motoric, motivational, and schedule factors (effort requirement, deprivation level, and schedule requirements, respectively) were manipulated. Bout analysis found that interresponse times (IRTs) were described by a mixture of two exponential distributions, one characterizing IRTs within response bouts, another characterizing intervals between bouts. Increasing effort requirement lengthened the shortest IRT (the refractory period between responses). Adding a ratio requirement increased the length and density of response bouts. Both manipulations also decreased the bout‐initiation rate. In contrast, food deprivation only increased the bout‐initiation rate. Changes in the distribution of IRTs over time showed that responses during extinction were also emitted in bouts, and that the decrease in response rate was primarily due to progressively longer intervals between bouts. Taken together, these results suggest that changes in the refractory period indicate motoric effects, whereas selective alterations in bout initiation rate indicate incentive‐motivational effects. These findings support the use of response‐bout analyses to identify the influence of pharmacological manipulations on processes underlying operant performance.  相似文献   
92.
A variety of studies suggest that a high need for closure--that is, a desire for knowledge that is clear, stable, and unambiguous as opposed to confusing or uncertain--may be associated with greater hostility toward relevant outgroups. Using international attitudes as the context, the authors examine the hypothesis that the relationship between the need for closure and support for military action against Iraq may be moderated by identification with the national ingroup. Specifically, it is expected that this relationship will be moderated by nationalism (i.e., an aggressive form of identification based on a desire for national dominance) but not patriotism (i.e., a more neutral love of one's country). The data provided a clear pattern of support for this hypothesis and additional analyses indicated that a high need for closure reduced variability about the use of force among the highly nationalistic but not the highly patriotic.  相似文献   
93.
Consolidation theory proposes that through the synthesis of new proteins recently acquired memories are strengthened over time into a stable long-term memory trace. However, evidence has accumulated suggesting that retrieved memory is susceptible to disruption, seeming to consolidate again (reconsolidate) to be retained in long-term storage. Here we show that intracortical blockade of protein synthesis in the gustatory cortex after retrieval of taste-recognition memory disrupts previously consolidated memory to a restricted degree only if the experience is updated. Our results suggest that retrieved memory can be modified as part of a mechanism for incorporating updated information into previously consolidated memory.  相似文献   
94.
    
Qigong is an ancient form of health maintenance, which is part of Traditional China Medicine. Numerous beneficial mental and physical effects have been classically ascribed to this traditional psychosomatic method. The purpose of this work has been to assess the effects of Taoist qigong practice on several hormonal parameters of the Hipotalamic‐Pituitary‐Adrenal axis and specific measures of psychological well‐being in healthy subjects. Forty‐three healthy volunteers participated in the study, of whom 22 were randomly allocated to the experimental group, and 21 were assigned to the control group. Experimental participants underwent a qigong training program for one month. Blood samples for the quantification of hormonal parameters, and several instruments to assess anxiety and depression symptoms as well as subjective sleep quality, were obtained before and after the program. Statistically significant differences were found between the experimental and control groups, with the experimental group showing lower blood levels of adrenocorticotropic hormone (ACTH). This study shows that Taoist qigong is a psychosomatic method able to exert a modulatory action on ACTH levels in healthy subjects. We consider the need to continue exploring the psychobiological modulation of this qigong method and its possible repercussion for human health care.  相似文献   
95.
    
ABSTRACT

Medicine regulation worldwide has undergone a process of regulatory diversification. The evidence-based medicine (EBM) paradigm, centered on multi-phase randomized controlled trials, is increasingly contested and replaced by new models of clinical validation. To explain these changes, STS research has cited just a few factors, e.g. growing pressure form health consumers; the role of pharmaceutical companies to lobby for fast, affordable drug development; the influence of neoliberal ideas and libertarian advocacy of deregulation; and the agency of national governments to enable domestic innovation opportunities in the context of global competition and inequalities. Those factors individually cannot account for the increasing variation in medicine regulation at both national and global levels. Instead it is helpful to integrate elements of existing explanations into a framework with four pairs of conflicting regulatory choices, which play a central role in the formation of medicine regulation. We use this framework to compare regulatory changes in the USA, European Union, China, India, Argentina, and Japan. Across these jurisdictions, the case studies illustrate four dynamics of diversification. Key regulatory concepts such as evidence, risk, safety, efficacy, responsibility and accountability acquire different meanings, reshaping medicine innovation in far-reaching and often contradictory ways. The boundaries between medical research and healthcare provision, commerce and humanitarian service, as well as state control and medical self-regulation are re-defined.  相似文献   
96.
A decline in navigational abilities is a consistent feature of aging. Although many studies focused on recall of navigational information, the impact of time and type of learning on recall has received little attention. We submitted older adults and young participants to an extensive training of an ecological environment, from both route and survey perspectives. Then, we tested participants’ learning using from both route and survey perspectives. Although older adults benefit from the extensive training, they did not reach the same performance of the young participants. Despite this main effect of age, the effect of the type of learning was the same in the two groups. Congruence between type of learning and recall led to better performance in both groups. We discuss these findings in the light of cognitive models of human navigation and aging. Useful suggestions about how these findings may inform a specific cognitive intervention in older adults are also provided.  相似文献   
97.
98.
    
Access to and control of resources is a major source of costly conflicts. Animals, under some conditions, respect what others control and use (i.e. possession). Humans not only respect possession of resources, they also respect ownership. Ownership can be viewed as a cooperative arrangement, where individuals inhibit their tendency to take others’ property on the condition that those others will do the same. We investigated to what degree great apes follow this principle, as compared to human children. We conducted two experiments, in which dyads of individuals could access the same food resources. The main test of respect for ownership was whether individuals would refrain from taking their partner's resources even when the partner could not immediately access and control them. Captive apes (N = 14 dyads) failed to respect their partner's claim on food resources and frequently monopolized the resources when given the opportunity. Human children (N = 14 dyads), tested with a similar apparatus and procedure, respected their partner's claim and made spontaneous verbal references to ownership. Such respect for the property of others highlights the uniquely cooperative nature of human ownership arrangements.  相似文献   
99.
Although the idea of dignity has always been applied to human beings and although its role is far from being uncontroversial, some recent works in animal ethics have tried to apply the idea of dignity to animals. The aim of this paper is to discuss critically whether these attempts are convincing and sensible. In order to assess these proposals, I put forward two formal conditions that any conception of dignity must meet (non-redundancy and normative determinacy) and outline three main approaches which might justify the application of dignity to animals: the species-based approach, moral individualism and the relational approach. Discussing in particular works by Martha Nussbaum and Michael Meyer I argue that no approach can convincingly justify the extension of dignity to animals because all fail to meet the formal conditions and do not provide an appropriate basis for animal dignity. I conclude by arguing that the recognition of the moral importance of animals and their defense should appeal to other normative concepts which are more appropriate than dignity.  相似文献   
100.
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