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991.
The environment of childhood poverty   总被引:2,自引:0,他引:2  
Poor children confront widespread environmental inequities. Compared with their economically advantaged counterparts, they are exposed to more family turmoil, violence, separation from their families, instability, and chaotic households. Poor children experience less social support, and their parents are less responsive and more authoritarian. Low-income children are read to relatively infrequently, watch more TV, and have less access to books and computers. Low-income parents are less involved in their children's school activities. The air and water poor children consume are more polluted. Their homes are more crowded, noisier, and of lower quality. Low-income neighborhoods are more dangerous, offer poorer municipal services, and suffer greater physical deterioration. Predominantly low-income schools and day care are inferior. The accumulation of multiple environmental risks rather than singular risk exposure may be an especially pathogenic aspect of childhood poverty.  相似文献   
992.
993.
Group interventions have assumed a growing role in primary prevention and supportive care for cancer and HIV disease. Earlier sections of this Special Report examined empirical findings for these interventions and provided recommendations for future research. The current section offers brief recommendations for service providers, policymakers, and stakeholders. Group services now occupy an increasingly prominent place in primary prevention programs and medical settings. In previous sections of this Special Report (Sherman, Leszcz et al., 2004; Sherman, Mosier et al., 2004a, 2004b) we examined the efficacy of different group interventions at different phases of cancer or HIV disease, considered characteristics of the intervention and the participants that might influence outcomes, and discussed mechanisms of action. Methodological challenges and priorities for future research were highlighted. In this, the final section, we offer brief recommendations for service providers, policymakers, and other stakeholders. We consider some of the barriers that constrain use of empirically-based group interventions and note how these programs might be implemented more widely and effectively.  相似文献   
994.
995.
In the analysis of memory it is commonly observed that, even after a memory is apparently forgotten, its latent presence can still be revealed in a subsequent learning task. Although well established on a behavioral level, the mechanisms underlying latent memory are not well understood. To begin to explore these mechanisms, we have used Aplysia, a model system that permits the simultaneous study of memory at the behavioral, cellular, and molecular levels. We first demonstrate that robust latent memory is induced by long-term sensitization training of the tail-elicited siphon withdrawal reflex. It is revealed by its ability to facilitate the subsequent induction of three mechanistically distinct temporal domains of sensitization memory: short-term, intermediate-term, and long-term memory. Under our training conditions, the latent memory persists for at least 2 d following the decay of original memory expression but appears to be gone by 4 d. Interestingly, we also find that latent memory is induced even in the absence of overt memory for the original training. These findings now permit the analysis of the cellular and molecular architecture of a common feature of learning and memory.  相似文献   
996.
Using a national sample of business professionals, the relationship between two measures of perceived organizational ethics and individuals' overall skepticism about women's employment were examined. After controlling for several demographic factors, analysis of responses from a 9% return suggested that persons working for companies believed to have strong ethical practices are less likely to have negative perceptions of women's employment.  相似文献   
997.
998.
Marcus GF 《Cognition》2006,101(2):443-465
Against a background of recent progress in developmental neuroscience, some of which has been taken as challenging to the modularity hypothesis of , this article contrasts two competing conceptions of modularity: sui generis modularity, according to which modules are treated as independent neurocognitive entities that owe nothing to one another, and descent-with-modification modularity, according to which current cognitive modules are understood to be shaped by evolutionary changes from ancestral cognitive modules. I argue that sui generis modularity is incompatible with a range of data, from the co-occurrence of deficits to the patterns of activation in neuroimaging studies, but that same range of data is compatible with descent-with-modification modularity. Furthermore, I argue that the latter conception of modularity may have important implications for the practice and conception of fields such as developmental disorders and linguistics.  相似文献   
999.
Perinatal asphyxia occurs in approximately 1-6 per 1000 live full-term births. Different patterns of brain damage can result, though the relation of these patterns to long-term cognitive-behavioural outcome remains under investigation. The hippocampus is one brain region that can be damaged (typically not in isolation), and this site of damage has been implicated in two different long-term outcomes, cognitive memory impairment and the psychiatric disorder schizophrenia. Factors in addition to the acute episode of asphyxia likely contribute to these specific outcomes, making prediction difficult. Future studies that better document long-term cognitive-behavioural outcome, quantitatively identify patterns of brain injury over development and consider additional variables that may modulate the impact of asphyxia on cognitive and behavioural function will forward the goals of predicting long-term outcome and understanding the mechanisms by which it unfolds.  相似文献   
1000.
This study examined the combined effects of caffeine and the personality attribute of trait-anger on the speed of psychomotor vigilance performance during sleep deprivation. 23 young adult soldiers (19 male) were administered the State-Trait Anger Expression Inventory-2 when well-rested. Participants were then sleep deprived for three consecutive nights (77 hours total) during which they completed repeated psychomotor vigilance testing. Half of the participants received four doses of oral caffeine (200 mg every 2 hr.; 800 mg total) each night, while the other half were administered a placebo. For the first night, higher scores on trait-anger, outward anger expression, and intensity of anger expression predicted better sustained overnight vigilance performance, but only for those volunteers receiving caffeine. These correlations were not significant for the subsequent nights. Findings suggest a possible synergistic effect between personality traits associated with arousal of the central nervous system and vigilance-promoting effects of caffeine.  相似文献   
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