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101.
Thirty-one first-year psychology graduate students in a computer applications course completed a set of structured problems, unstructured problems, and data-screening problems in each of two statistical computing environments: a menu-based interface (SPSS for Windows) and a traditional command-based interface (SPSSx). Performance on the menu-based interface was generally superior to performance on the command-based interface. More of the structured problems were completed successfully within the menu-based interface. The menu-based interface also facilitated error identification, was rated as easier to use, and was preferred nearly 4 to 1 over the command-based interface. For the unstructured problems, students identified more relationships in the data set and issued more statistical commands when working with the menu-based interface. These findings are consistent with the interpretation that because the menu-based interface requires fewer mental resources to be dedicated to the mechanics of analysis, more resources are available to devote to higher level problem solving.  相似文献   
102.
Estrogen and Neural Plasticity   总被引:3,自引:0,他引:3  
Converging clinical evidence suggests that postmenopausal estrogen therapy in women is associated with improved cognition and a reduced incidence of Alzheimer's disease. In experimental work, investigators have found estrogen to promote changes in synaptic plasticity within the nervous system. In this article, we review both the clinical and the experimental literature, and consider mechanisms of action of estrogen on neurons and synaptic plasticity, and how they might protect against the cognitive impairments of old age.  相似文献   
103.
104.
The effectiveness of tetraethylammonium (TEA) and high-frequency stimulation (HFS) in inducing long-term synaptic modification is compared in CA1 and dentate gyrus (DG) in vitro. High-frequency stimulation induces long-term potentiation (LTP) at synapses of both perforant path-DG granule cell and Schaffer collateral-CA1 pyramidal cell pathways. By contrast, TEA (25 mM) induces long-term depression in DG while inducing LTP in CA1. The mechanisms underlying the differential effect of TEA in CA1 and DG were investigated. It was observed that T-type voltage-dependent calcium channel (VDCC) blocker, Ni2+ (50 microM), partially blocked TEA-induced LTP in CA1. A complete blockade of the TEA-induced LTP occurred when Ni2+ was applied together with the NMDA receptor antagonist, D-APV. The L-type VDCC blocker, nifidipine (20 microM), had no effect on CA1 TEA-induced LTP. In DG of the same slice, TEA actually induced long-term depression (LTD) instead of LTP, an effect that was blocked by D-APV. Neither T-type nor L-type VDCC blockade could prevent this LTD. When the calcium concentration in the perfusion medium was increased, TEA induced a weak LTP in DG that was blocked by Ni2+. During exposure to TEA, the magnitude of field EPSPs was increased in both CA1 and DG, but the increase was substantially greater in CA1. Tetraethylammonium application also was associated with a large, late EPSP component in CA1 that persisted even after severing the connections between CA3 and CA1. All of the TEA effects in CA1, however, were dramatically reduced by Ni2+. The results of this study indicate that TEA indirectly acts via both T-type VDCCs and NMDA receptors in CA1 and, as a consequence, induces LTP. By contrast, TEA indirectly acts via only NMDA receptors in DG and results in LTD. The results raise the possibility of a major synaptic difference in the density and/or distribution of T-type VDCCs and NMDA receptors in CA1 and DG of the rat hippocampus.  相似文献   
105.
The effectiveness of tetraethylammonium (TEA) and high-frequency stimulation (HFS) in inducing long-term synaptic modification is compared in CA1 and dentate gyrus (DG) in vitro. High-frequency stimulation induces long-term potentiation (LTP) at synapses of both perforant path-DG granule cell and Schaffer collateral-CA1 pyramidal cell pathways. By contrast, TEA (25 mM) induces long-term depression in DG while inducing LTP in CA1. The mechanisms underlying the differential effect of TEA in CA1 and DG were investigated. It was observed that T-type voltage-dependent calcium channel (VDCC) blocker, Ni2+ (50 μM), partially blocked TEA-induced LTP in CA1. A complete blockade of the TEA-induced LTP occurred when Ni2+ was applied together with the NMDA receptor antagonist, D-APV. The L-type VDCC blocker, nifidipine (20 μM), had no effect on CA1 TEA-induced LTP. In DG of the same slice, TEA actually induced long-term depression (LTD) instead of LTP, an effect that was blocked by D-APV. Neither T-type nor L-type VDCC blockade could prevent this LTD. When the calcium concentration in the perfusion medium was increased, TEA induced a weak LTP in DG that was blocked by Ni2+. During exposure to TEA, the magnitude of field EPSPs was increased in both CA1 and DG, but the increase was substantially greater in CA1. Tetraethylammonium application also was associated with a large, late EPSP component in CA1 that persisted even after severing the connections between CA3 and CA1. All of the TEA effects in CA1, however, were dramatically reduced by Ni2+. The results of this study indicate that TEA indirectly acts via both T-type VDCCs and NMDA receptors in CA1 and, as a consequence, induces LTP. By contrast, TEA indirectly acts via only NMDA receptors in DG and results in LTD. The results raise the possibility of a major synaptic difference in the density and/or distribution of T-type VDCCs and NMDA receptors in CA1 and DG of the rat hippocampus.  相似文献   
106.
This note from the classroom suggests that multicolor highlighting is a useful study technique for religious studies students. The note first reviews the literature regarding the effectiveness of traditional highlighting, then discusses advantages of the modified technique. Monochrome highlighting works only if readers select text through a discriminating reading process. Reading in colors fosters this sort of active reading. It prompts readers to ask how and why a given term, phrase or passage is important. This technique can help students grasp the basic categories and concepts of the discipline and it can embody course requirements or learning outcomes. The note concludes with practical suggestions for using the technique in the classroom.  相似文献   
107.
108.
Two experiments addressed the question of whether news reports depicting base‐rate data indicative of increasing population size over time would assuage the apprehension and victimization risk associated with another news story depicting frequency increases in a threatening phenomenon during the same time period. Men exposed to the population data manifested lower levels of apprehension and victimization risk than men not exposed to such data, but women showed no reduction in either apprehension and victimization risk than men not exposed to such data, but women showed no reduction in either apprehension or victimization risk after exposure to population data. This interaction was replicated in both experiments. Experiment 2 demonstrated that the same interaction can be produced using base‐rate data other than that depicting population increases over time and that the effects of the base‐rate stories are not merely a product of distraction from the threatening story. Differences in apprehension levels, information processing styles, mathematical problems solving skill, and sex role response sets were considered as alternative explanations for the interaction.  相似文献   
109.
This study investigated the influence of a child’s DRD4 risk, parental levels of ADHD symptoms, and the interactive influence of these factors on the development of preschool aggression. Additionally, the study investigated the role of home chaos as a mediator between parental ADHD symptoms and child aggression. The sample consisted of 84 4.5-year-old children and their parents. Children were genotyped for the DRD4 polymorphism. ADHD symptoms were self-reported by parents when the child was 2 to 6 months old. Parental reports of home chaos and the child’s aggression were collected 4 years later. Child’s DRD4 risk and parental ADHD symptoms significantly contributed to the prediction of preschool aggression. However, contrary to our hypotheses, no interactions were found between the child’s DRD4 risk and the levels of parental ADHD symptoms. Home chaos played a mediating role in the relation between paternal ADHD symptoms and the child’s aggression. The relation between maternal ADHD symptoms and the child’s aggression was not significantly mediated through the level of home chaos. The current study emphasizes the importance of longitudinally investigating the contribution of parental ADHD symptoms to child aggression, while also exploring the differential contribution of maternal/paternal inattention and hyperactivity-impulsivity symptoms. Moreover, home chaos was found to be a significant environmental mechanism through which paternal ADHD symptoms affect children’s aggression in the preschool years.  相似文献   
110.
In recent years motivational researchers have spent considerable time examining race/ethnicity and gender differences in academic and social achievement goals, but little time examining the influence of socioeconomic status (SES). This lack of attention is surprising given that both student motivation and SES have been shown to predict academic attainment. This study surveyed the academic and social achievement goal orientations of 16–17 year old students (n = 130) attending two schools with markedly different socioeconomic profiles. Analyses showed significant differences between the schools on the academic achievement goal scales, with students at the low SES school less likely to endorse adaptive combinations of mastery and performance goals than their high SES counterparts. Students who did not expect to finish senior high school also endorsed social goals that may manifest as disruptive behaviours in the classroom. The findings suggest that SES may influence the adoption of academic achievement goals but not necessarily social achievement goals. Implications for theory and research are discussed.  相似文献   
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