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991.
Memory persistence is a dynamic process involving the reconsolidation of memories after their reactivation. Reconsolidation impairments have been demonstrated for many types of memories in rats, and signaling at N-methyl-d-aspartate (NMDA) receptors appears often to be a critical pharmacological mechanism. Here we investigated the reconsolidation of appetitive pavlovian memories reinforced by natural rewards. In male Lister Hooded rats, systemic administration of the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-SH-dibenzo{a,d}cyclohepten-5,10-imine maleate (MK-801, 0.1 mg/kg i.p.) either before or immediately following a brief memory reactivation session abolished the subsequent acquisition of a new instrumental response with sucrose conditioned reinforcement. However, only when injected prior to memory reactivation was MK-801 effective in disrupting the maintenance of a previously-acquired instrumental response with conditioned reinforcement. These results demonstrate that NMDA receptor-mediated signaling is required for appetitive pavlovian memory reconsolidation.  相似文献   
992.
Hispanic individuals in the U.S. have been disproportionately impacted by HIV/AIDS, yet little is known regarding the neuropsychological sequelae of HIV within the Hispanic population. This study characterized neuropsychological (NP) test performance of HIV+ English-speaking Hispanic participants (n = 51) and investigated the combined roles of sociocultural factors (e.g., ethnicity, socioeconomic status [SES] proxy, and reading level) on NP test performance among our HIV+ Hispanic and non-Hispanic White participants (n = 49). Results revealed that the pattern of NP impairment in HIV+ Hispanic participants is consistent with the frontal-striatal pattern observed in HIV-associated CNS sequelae, and the overall prevalence of global NP impairment was high compared to previous reports with more ethnically homogeneous, non-Hispanic White cohorts. Multivariate prediction models that considered both sociocultural factors and CD4 count revealed that reading level was the only unique predictor of global NP functioning, learning, and attention/working memory. In contrast, ethnicity was the only unique predictor of abstraction/executive functioning. This study provides support for the use of neuropsychological evaluation in detecting HIV-associated NP impairment among HIV+ Hispanic participants and adds to the growing literature regarding the importance of considering sociocultural factors in the interpretation of NP test performance.  相似文献   
993.
Research on navigation has shown that humans and laboratory animals recover their sense of orientation primarily by detecting geometric properties of large-scale surface layouts (e.g. room shape), but the reasons for the primacy of layout geometry have not been clarified. In four experiments, we tested whether 4-year-old children reorient by the geometry of extended wall-like surfaces because such surfaces are large and perceived as stable, because they serve as barriers to vision or to locomotion, or because they form a single, connected geometric figure. Disoriented children successfully reoriented by the shape of an arena formed by surfaces that were short enough to see and step over. In contrast, children failed to reorient by the shape of an arena defined by large and stable columns or by connected lines on the floor. We conclude that preschool children's reorientation is not guided by the functional relevance of the immediate environmental properties, but rather by a specific sensitivity to the geometric properties of the extended three-dimensional surface layout.  相似文献   
994.
The purpose of this paper is to consider Joshua Gert’s novel view of subjective practical rationality in his book Brute Rationality. After briefly outlining the account, I present two objections to his view and then consider his own objections to a rival approach to understanding subjective rationality which I take to be much more plausible.
Christian MillerEmail:
  相似文献   
995.
We all long for relationships with others, because only in connecting with others can we develop our intrapsychic structure and become functional adults. We are psychologically predisposed to have a constant connection with others and are driven toward relationships with others. Our deepest yearnings are therefore devoted to building solid dialogue as the means of becoming fully human. We, therefore, consciously or unconsciously, long for a relationship where we can experience happiness, satisfaction and, above all, redemption or salvation from our dreads, miseries and unhappiness. In this article we presuppose that a therapeutic relationship, demonstrated in a psychoanalytic setting, namely in relational family therapy, can contain redemptive dimensions in which the inextinguishable longing for salvation is always present.
Christian GostecnikEmail:
  相似文献   
996.
Although it is assumed that there are negative social consequences for individuals missing visible front teeth, no study of the way in which edentulous individuals were perceived in a social context and the potential social repercussions could be located. This initial study concerned college students' perceptions of individuals missing visible upper front teeth. 200 volunteers, 19 to 50 years of age (M = 20.6, SD = 4.4), rated five photographs depicting tooth presence or absence, from a full dentition to missing as many as four upper front teeth, on social traits including attractiveness, health status, educational attainment, satisfaction with life, active social life, aggressiveness, intelligence, trustworthiness, amount of caring, friendship, dating, and likelihood to live as a neighbor. Analysis suggested a person missing visible teeth was more negatively perceived on all social traits than a person with full dentition. Results were strongest when students were proposed to be linked to the edentulous individual in a personal way, i.e., dating or living as neighbor. Men and women agreed on perceptions of social traits and dentition condition. These results suggest the presence of strong Western cultural values, whereby those who are missing teeth may experience significant barriers to personal and social success.  相似文献   
997.
The constant-RPE tracking model monitors progress over the course of exercise training. During aerobic exercise, prior work using this model has demonstrated similar relative intensities pre- and posttraining, while the absolute workload increases posttraining. However, the prediction equation associated with these changes has not been examined during resistance training. 22 men and 27 women (M age 64 yr.) participated in a 12-wk. resistance training. Orientation determined resistances associated with RPEs of 4, 5-6, 7-8, and 9 on the OMNI-Resistance Exercise Scale for each of seven exercises for each participant. Individuals trained 3 days a week for 12 wk. Linear regression was used to calculate percent of 1-repetition maximum (%1-RM) at RPE 4, 6, and 8 for the exercises. Paired sample t tests, comparing pre- and posttraining %1-RMs at each RPE, indicated that posttraining %1-RMs were higher for RPE 4 and 6 for each exercise, while at RPE 8, results were significant for only 3 exercises. Thus for at least the RPE 4 and 6, the constant RPE tracking model is appropriate for resistance exercise; however, the equation of prediction appears to differ from that for aerobic exercise. Development of a new prediction equation may be necessary to track relative strength in older adults.  相似文献   
998.
Do differences in individualism and collectivism influence values, self-concept content, relational assumptions, and cognitive style? On the one hand, the cross-national literature provides an impressively consistent picture of the predicted systematic differences; on the other hand, the nature of the evidence is inconclusive. Cross-national evidence is insufficient to argue for a causal process, and comparative data cannot specify if effects are due to both individualism and collectivism, only individualism, only collectivism, or other factors (including other aspects of culture). To address these issues, the authors conducted a meta-analysis of the individualism and collectivism priming literature, with follow-up moderator analyses. Effect sizes were moderate for relationality and cognition, small for self-concept and values, robust across priming methods and dependent variables, and consistent in direction and size with cross-national effects. Results lend support to a situated model of culture in which cross-national differences are not static but dynamically consistent due to the chronic and moment-to-moment salience of individualism and collectivism. Examination of the unique effects of individualism and collectivism versus other cultural factors (e.g., honor, power) awaits the availability of research that primes these factors.  相似文献   
999.
In many psychophysical experiments, the participant's task is to detect small changes along a given stimulus dimension or to identify the direction (e.g., upward vs. downward) of such changes. The results of these experiments are traditionally analyzed with a constant-variance Gaussian (CVG) model or a high-threshold (HT) model. Here, the authors demonstrate that for changes along three basic sound dimensions (frequency, intensity, and amplitude-modulation rate), such models cannot account for the observed relationship between detection thresholds and direction-identification thresholds. It is shown that two alternative models can account for this relationship. One of them is based on the idea of sensory quanta; the other assumes that small changes are detected on the basis of Poisson processes with low means. The predictions of these two models are then compared against receiver operating characteristics (ROCs) for the detection of changes in sound intensity. It is concluded that human listeners' perception of small and unidimensional acoustic changes is better described by a discrete-state Poisson model than by the more commonly used CVG model or by the less favored HT and quantum models.  相似文献   
1000.
Previous empirical research has been unable to find a sufficient correlation between subjective well-being and per capita income, being hampered by limited longitudinal information and an inability to account for the predictions of competing theories. We bring new evidence to this question by exploiting a long and complete time-series from the Eurobarometer Survey, 1973–2002 allowing an examination of trends in life satisfaction across 15 European countries employing a modified version of Kendall’s Tau. Our results show that while current GDP growth does not affect trends in well-being, accelerations in GDP growth do. In addition, faster GDP growth and faster growth of government consumption than in neighbouring countries induces positive trends in life satisfaction. Our findings are consistent with the predictions of aspirations theory and the theory of reference group comparisons.  相似文献   
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