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941.
Memory representations are reactivated during slow-wave sleep (SWS) after learning, and these reactivations cause a beneficial effect of sleep for memory consolidation. Memory reactivations can also be externally triggered during sleep by associated cues which enhance the sleep-dependent memory consolidation process. Here, we compared in humans the influence of sleep periods (i) of 40min and (ii) of 90min without externally triggered reactivations and (iii) of externally triggered reactivations by an associated odor cue during a 40-min sleep period on the consolidation of previously learned hippocampus-dependent visuo-spatial memories. We show that external reactivation by an odor cue during the 40-min sleep period enhanced memory stability to the same extent as 90min of sleep without odor reactivation. In contrast, 40min of sleep without external reactivations were not sufficient to benefit memory. In the 90-min sleep condition, memory enhancements were associated with time spent in SWS and were independent of the presence or absence of REM sleep. These results suggest that the efficacy of hippocampus-dependent memory consolidation depends on the duration of sleep and particularly SWS. External reactivation cues can accelerate the consolidation process even during shorter sleep episodes.  相似文献   
942.
The present study explored different approaches for automatically scoring student essays that were written on the basis of multiple texts. Specifically, these approaches were developed to classify whether or not important elements of the texts were present in the essays. The first was a simple pattern-matching approach called "multi-word" that allowed for flexible matching of words and phrases in the sentences. The second technique was latent semantic analysis (LSA), which was used to compare student sentences to original source sentences using its high-dimensional vector-based representation. Finally, the third was a machine-learning technique, support vector machines, which learned a classification scheme from the corpus. The results of the study suggested that the LSA-based system was superior for detecting the presence of explicit content from the texts, but the multi-word pattern-matching approach was better for detecting inferences outside or across texts. These results suggest that the best approach for analyzing essays of this nature should draw upon multiple natural language processing approaches.  相似文献   
943.
We predicted that the perceived likelihood of acquiring a hoped-for thin self would mediate perfectionistic strivings on dietary restraint, and that the perceived likelihood of acquiring a feared fat self would mediate perfectionistic concerns on dietary restraint. We also predicted that the mediation pathway from perfectionistic concerns to dietary restraint would have a greater impact than that from perfectionistic strivings. Participants were 222 female college students who reported their height and weight and completed measures of perfectionism, the likelihood of acquiring the feared fat and hoped-for thin selves, and dietary restraint. Statistical analyses revealed that the perceived likelihood of acquiring the feared fat self mediated both perfectionistic concerns and perfectionistic strivings on dietary restraint, and that the mediating pathway from perfectionistic concerns to dietary restraint was greater than that from perfectionistic strivings. Implications for future research and eating pathology interventions are discussed.  相似文献   
944.
Why is conversation so easy?   总被引:1,自引:0,他引:1  
Traditional accounts of language processing suggest that monologue--presenting and listening to speeches--should be more straightforward than dialogue--holding a conversation. This is clearly not the case. We argue that conversation is easy because of an interactive processing mechanism that leads to the alignment of linguistic representations between partners. Interactive alignment occurs via automatic alignment channels that are functionally similar to the automatic links between perception and behaviour (the so-called perception-behaviour expressway) proposed in recent accounts of social interaction. We conclude that humans are "designed" for dialogue rather than monologue.  相似文献   
945.
The human capacity for acquiring speech and language must derive, at least in part, from the genome. In 2001, a study described the first case of a gene, FOXP2, which is thought to be implicated in our ability to acquire spoken language. In the present article, we discuss how this gene was discovered, what it might do, how it relates to other genes, and what it could tell us about the nature of speech and language development. We explain how FOXP2 could, without being specific to the brain or to our own species, still provide an invaluable entry-point into understanding the genetic cascades and neural pathways that contribute to our capacity for speech and language.  相似文献   
946.
947.
The Psychological Techniques of Martin Luther Thomas' Radio Addresses (Adorno, 2000) echoes Adorno's analogous critique of the culture industry by detecting an ideological effect, prior to any given content, intrinsic to the form of radio religion. Notwithstanding the text's narrowness, I argue that Adorno's analysis of Thomas' ‘fait accompli technique’—presenting claims as previously established certainties—was both typical of his work and insightful for issues in cultural criticism. First, it refused subjectivist reductions of sociological effects to false consciousness. Second, it warned that historicism runs the risk of repeating the fait accompli when it treats what exists empirically as the only possible reality, or when it treats empirical givens as representatives of a future redemption. I argue that Adorno's dismissal of religious radio was consistent with his critique of positivism, and that the Thomas study models an historicist methodology that refuses, against its own logic, to reduce otherness to its own categories.  相似文献   
948.
The purpose of this study was to test children's academic self-concept, family socioeconomic status, family structure (single parent vs. two parent family) and academic achievement in elementary school as predictors of children's educational attainment level in young adulthood within a ten-year longitudinal design. Participants (254 girls, 211 boys) were three cohorts of students in Grades 3, 4, and 5 from ten elementary schools. Results from structural equation modeling revealed that academic self-concept predicted educational attainment level ten years later over and above prior achievement. Moreover, this pattern of results was invariant across cohorts. In addition, regression analyses based on a restricted sample (n?=?243) indicated that the academic self-concept/educational attainment level relation was still significant while controlling for family SES, family structure (single parent vs. two parent family), and academic achievement. Discussion focuses on the theoretical and practical implications of the results.  相似文献   
949.

Scholars have debated the role that altruistic considerations play—and should play—in recruitment and decision-making processes for clinical trials. Little empirical data are available to support their various perspectives. We analyzed 140 audiotaped pediatric informed consent sessions, of which 95 (68%) included at least one discussion of how participation in a cancer clinical trial might benefit: 1) the pursuit of scientific knowledge generally; 2) other children with cancer specifically; and 3) “the future” and other vaguely defined recipients. Clinicians initiated most (80%) of these discussions of altruism. The enrollment rate of children in the clinical trial was high (83%) overall, but not higher among children whose parents were involved in an altruism-oriented discussion. These findings suggest that: (1) clinicians invoke a spectrum of altruistic considerations rather than a single monothematic notion of altruism, and (2) the effect of altruistic considerations on subsequent enrollment decisions is marginal. While further research on this topic is warranted, bioethical debate should strive to reflect the diversity of altruistic discourse in clinical research encounters and to place this discourse in the context of other, including nonaltruistic, considerations.  相似文献   
950.
The increasing incidence of breast cancer in the Arab world, coupled with a relatively early age of onset, raises concern for the presence of hereditary risk factors in this population. However, due to potential structural and cultural barriers, Arab Americans make up the smallest percentage of individuals tested for Hereditary Breast and Ovarian Cancer Syndrome in the United States. The objectives of this qualitative pilot focus group of 13 Arab-American women were to explore attitudes, knowledge and beliefs regarding hereditary breast cancer in the Arab-American community in metropolitan Detroit, identify barriers that would prevent women from seeking hereditary cancer screening/testing and determine who women would talk to about inherited cancer. Results indicated that cultural beliefs and personal experiences with cancer influenced the women’s perspectives on hereditary cancer risk. A high level of secrecy about cancer within Arab-American families was present, which may prevent accurate risk assessment and referral for genetic services. Other identified barriers that may influence hereditary risk assessment included stigma, fears and misconceptions of cancer. While these barriers were present, participants also expressed a strong need for education and tailored cancer risk information for their community.  相似文献   
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