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211.
One difficulty plaguing research on dispositional optimism and health is whether optimism and pessimism are bipolar opposites or constitute distinct constructs. The present study examined the Life Orientation Test to determine whether the two-factor structure is explained by method bias (due to measurement) or substantive differences. The authors compared three measurement models: bipolar, bivariate, and method artifact. Optimism and pessimism emerged as distinct constructs due to substantive differences. The authors also considered the validity of optimism and pessimism, examining their relations with psychological and physical health outcomes. Optimism and pessimism were more similar in relation to psychological health than to other health-related behavior or physical health outcomes. However, a strongly interpretable pattern for the relation of optimism and pessimism to the health outcomes did not emerge. Further research may benefit from considering optimism and pessimism as bivariate and also should consider the conceptual components and behavioral mechanisms specific to each variable.  相似文献   
212.
Food caching birds hide food and recover the caches when supplies are less abundant. There is, however, a risk to this strategy because the caches are susceptible to pilfering by others. Corvids use a number of different strategies to reduce possible cache theft. Scrub-jays with previous experience of pilfering other's caches cached worms in two visuospatially distinct caching trays either in private or in the presence of a conspecific. When these storers had cached in private, they subsequently observed both trays out of reach of a conspecific. When these storers had cached in the presence of a conspecific, they subsequently watched the observer pilfering from one of the trays while the other tray was placed in full view, but out of reach. The storers were then allowed to recover the remaining caches 3 h later. Jays cached more worms when they were observed during caching. At the time of recovery, they re-cached more than if they had cached in private, selectively re-caching outside of the trays in sites unbeknown to potential thieves. In addition, after a single pilfering trial, the jays switched their recovery strategy from predominantly checking their caches (i.e. returning to a cache site to see whether the food remained there) to predominantly eating them. Re-caching remained constant across the three trials. These results suggest that scrub-jays use flexible, cognitive caching and recovery strategies to aid in reducing potential future pilfering of caches by conspecifics.  相似文献   
213.
Exploration is the primary way in which rodents gather information about their spatial surroundings. Thus, spatial theories propose that damage to the hippocampus, a structure thought to play a fundamental role in spatial behavior, should disrupt exploration. Exploration in rats is organized. The animals create home bases that are central to exploratory excursions and returns, and hippocampal formation damage alters the organization of exploration by disrupting returns. Mice do not appear to readily establish home bases in novel environments, thus, for this species, it is more difficult to establish the contribution of the hippocampus to exploration. The purpose of the present study was threefold: develop a task in which mice center their exploration from a home base, determine whether the exploratory behavior is organized, and evaluate the role of fimbria-fornix lesions on exploration. Mice were given a novel exploratory task in which their nesting material was placed on a large circular table. Video records of control and fimbria-fornix mice were made in both light and dark (infrared light) conditions. Exploration patterns (outward trips, stops, and homeward trips) were reconstructed from the video records. Control mice centered their activity on their bedding, from which they made circuitous outward trips marked by many stops, and periodic direct returns. The bedding-centered behavior and outward trips of the fimbria-fornix mice were similar to those of the control mice, but significantly fewer direct return trips occurred. The direct homeward trips observed under light and dark conditions were consistent with a dead-reckoning strategy, in which an animal computes its present position and homeward trajectory from self-movement cues generated on the outward trip. Because the fimbria-fornix lesions disrupted the homeward component of exploratory trips, we conclude that the fimbria-fornix may contribute to dead reckoning in mice. The results also show that the home-bedding methodology facilitates the establishment of a home base by mice, thus providing a useful methodology for studies with mice.  相似文献   
214.
Drug addiction is characterized by a set of recurring processes (intoxication, withdrawal, craving) that lead to the relapsing nature of the disorder. We have used positron emission tomography to investigate in humans the role of dopamine (DA) and the brain circuits it regulates in these processes. We have shown that increases in DA are associated with the subjective reports of drug reinforcement corroborating the relevance of drug-induced DA increases in the rewarding effects of drugs in humans. During withdrawal we have shown in drug abusers significant reductions in DA D2 receptors and in DA release. We postulate that this hypodopaminergic state would result in a decreased sensitivity to natural reinforcers perpetuating the use of the drug as a means to compensate for this deficit and contributing to the anhedonia and dysphoria seen during withdrawal. Because the D2 reductions are associated with decreased activity in the anterior cingulate gyrus and in the orbitofrontal cortex we postulate that this is one of the mechanisms by which DA disruption leads to compulsive drug administration and the lack of control over drug intake in the drug-addicted individual. This is supported by studies showing that during craving these frontal regions become hyperactive in proportion to the intensity of the craving. Craving is also associated with activation of memory circuits including the amygdala (implicated in conditioned learning), hippocampus (implicated in declarative learning), and dorsal striatum (implicated in habit learning) all of which receive DA innervation. We therefore postulate that dopamine contributes to addiction by disrupting the frontal cortical circuits that regulate motivation, drive, and self-control and by memory circuits that increase the motivational salience of the drug and drug-associated stimuli.  相似文献   
215.
This study examined how a fundamental principle of induction and scientific reasoning, information diversity, could be used to promote change in children's mental models of the earth's shape. Six-year-old children (N=132) were randomly allocated to a control or to one of two training conditions. Some training groups received instruction that simultaneously challenged children's beliefs concerning (a) why the earth appears flat to a surface observer and (b) the role of gravity. Others received instruction that repeatedly challenged only one of these beliefs. An adaptation of the Vosniadou and Brewer (1992, Cognitive Psychology 24, 535-585) protocol for identifying mental models of the earth was administered before and after instruction. Both instruction methods produced increases in factual knowledge. Only children receiving instruction about two core beliefs, however, showed an increased rate of acceptance of a spherical earth model at posttest. The findings show that instruction that challenges diverse aspects of children's na?ve scientific beliefs is more likely to produce conceptual change.  相似文献   
216.
The social reality of the imaginary audience: a grounded theory approach   总被引:2,自引:0,他引:2  
Bell JH  Bromnick RD 《Adolescence》2003,38(150):205-219
Traditional approaches to understanding the imaginary audience are challenged in this study. Three hundred sixty-one British schoolchildren (aged 14 and 15 years) were asked to express their worries and concerns, using grounded theory methodology. Qualitative responses were collated and coded according to emerging categories, with "what other people think" identified as the central concern. In particular, the findings are used to critique Elkind's (1967) theory of adolescent egocentrism. Data presented in this study suggest that adolescents worry about what other people think because there are real personal and social consequences. Such concerns are seen as being based in social reality and are not imaginary as Elkind suggested. In conclusion, new methodologies which place young people at the center of the analysis are advocated.  相似文献   
217.
Journal of Child and Family Studies - Pediatric cancer diagnosis and treatment can impact the psychological adjustment and quality of life (QOL) of caregivers. We examined: (a) the relationship...  相似文献   
218.

In a recent paper Mandy Simons has argued that in a Gricean framework there is room for embedded pragmatic effects. One of her goals has been to demonstrate that an argument put forward by François Recanati to the effect that it is not possible to apply Gricean reasoning to generation of local pragmatic effects is mistaken. In his commentary Recanati maintains that the view suggested by Simons can be called Gricean only in a very broad sense and insists that the process responsible for local effects is essentially different from the one which generates conversational implicatures. In my view their exchange highlights important issues concerning the way in which local pragmatic effects are generated and is worthy of a careful analysis. In what follows I critically examine Simons’s and Recanati’s views and then suggest the view that in the light of this analysis seems to me the most adequate. In particular, I argue—against Recanati—that during the interpretation process interpreters construct literal propositional nuclei, which usually fell short of being truth-evaluable but which play an important role in the interpretation. I claim that the view that assumes that such literal propositions are constructed in the process of interpretation is more universal and may be used to analyse a wider range of examples than the view that does not postulate such constructions. Nevertheless, I maintain—against Simons—that the global and local pragmatic inferences are importantly different.

  相似文献   
219.
In this response to David Bradnick's and Bradford McCall's defense of Amos Yong's usage of emergence theory, we defend our previous argument regarding the tension between Yong's Pentecostal commitments and the philosophical entailments of emergence theory. We clarify and extend our previous concerns in three ways. First, we explore the difficulties of construing divine action naturalistically (i.e. natural divine causation). Second, we clarify the problems of employing supervenience in theology. Third, we show why Bradnick's and McCall's advice to Yong to adopt weak emergence is theologically costly. In conclusion, it is suggested that theologians within the science and religion dialogue should not fear, but recover, the language of supernaturalism and dualism.  相似文献   
220.
Huntington disease (HD) is an autosomal dominant, progressive neurodegenerative disorder for which there is no cure. Predictive testing for HD is available to asymptomatic at-risk individuals. Approximately half of the population undergoing predictive testing for HD consists of young adults (≤35 years old). Finishing one’s education, starting a career, engaging in romantic relationships and becoming a parent are key milestones of young adulthood. We conducted a qualitative study to explore how testing gene-positive for HD influences young adults’ attainment of these milestones, and to identify major challenges that pre-symptomatic young adults face to aid the development of targeted genetic counseling. Results of our study demonstrate that 1) knowing one’s gene-positive status results in an urgency to reach milestones and positively changes young adults’ approach to life; 2) testing positive influences young adults’ education and career choices, romantic relationships, and family planning; 3) young adults desire flexible and tailored genetic counseling to address needs and concerns unique to this population. Findings of this study contribute to the understanding of the impact of predictive testing for HD on young adults, and highlight issues unique to this population that call for further research, intervention and advocacy.  相似文献   
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