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131.
132.
The standard of living reflected by one’s income and consumption is the primary explanation for the utility or satisfaction of the private consumer. However, empirical evidence very often demonstrates that the level of happiness is not necessarily higher for wealthy people in comparison to the poor. This holds within specific populations of a country, and in macro terms by comparison between the happiness of populations with low and high GDPppp per capita. Different research studies have used other economic and social explanatory variables for determining consumer happiness within countries. The present paper adds the new factor of income inequality that affects happiness. It is empirically proved that at extreme values of inequality measured by the Gini index, the effect of happiness is negative regardless of GDPppp per capita. However, at the intermediate ranges of the Gini index the effect of changes in the index on happiness is ambiguous. These results are found regardless of the actual values of GDPppp per capita.  相似文献   
133.
134.
The goal of this study was to assess neuropsychological functioning in nonreferred siblings of children with attention deficit/hyperactivity disorder (ADHD). Participants were 156 siblings of ADHD probands with (N = 40) and without (N = 116) ADHD (according to criteria of the Diagnostic and Statistical Manual of Mental Disorders (3rd edition, revised; American Psychiatric Association, 1987) and 118 siblings of non-ADHD normal controls of similar age, IQ, and grade level. Information on attention, executive, and memory functions was obtained in a standardized manner without knowledge of clinical status. Compared with siblings of controls, siblings with ADHD were significantly impaired on the Stroop test and on verbal learning and memory. In contrast, siblings without ADHD were similar to controls on virtually all measures. These data suggest that some executive, attention, and verbal learning deficits are found in nonreferred individuals with ADHD but that neuropsychological deficits are unlikely to constitute an endophenotype to ADHD.  相似文献   
135.
The neuropsychological profile of a man with a developmental surface dyslexia is presented here. This case study is of interest because J.C. exhibited a pattern of cognitive disorders rarely documented in previous data. Results showed that JC's difficulties in reading comprehension were closely related to complex memory disorders and were also associated with cognitive slowness. The present observations do not support the visual memory failure hypothesis. The data rather suggest that the core difficulty primarily lies with the nonautomatization of grapheme-phoneme correspondence rules, which in turn dramatically contributed to lexicon weaknesses. The hypothesis of a timing mechanism in reading disorders is discussed.  相似文献   
136.
Freestanding and bound morphemes differ in many (psycho)linguistic aspects. Some theorists have claimed that the representation and retrieval of freestanding and bound morphemes in the course of language production are governed by similar processing mechanisms. Alternatively, it has been proposed that both types of morphemes may be selected for production in different ways. In this article, the authors first review the available experimental evidence related to this topic and then present new experimental data pointing to the notion that freestanding and bound morphemes are retrieved following distinct processing principles: freestanding morphemes are subject to competition, bound morphemes not.  相似文献   
137.
E. Hazeltine, D. Teague, and R. B. Ivry have presented data that have been interpreted as evidence against a central bottleneck. This article describes simulations of their Experiments 1 and 4 in the ACT-R cognitive architecture, which does possess a central bottleneck in production execution. The simulation model is capable of accounting for the emergence of near-perfect timesharing in Experiment 1 and the detailed data on the distribution of response times from Experiment 4. With practice, the central bottleneck in ACT-R will be reduced to a maximum of 50 ms (1 production cycle) and can often be much less, depending on timing of stages and variability in their times. The authors also show, with a mathematical analysis of E. Hazeltine et al.'s Experiment 2, that the expected dual costs for these kinds of highly practiced tasks will be small in many circumstances, often under 10 ms.  相似文献   
138.
Emerging parallel processing and increased flexibility during the acquisition of cognitive skills form a combination that is hard to reconcile with rule-based models that often produce brittle behavior. Rule-based models can exhibit these properties by adhering to 2 principles: that the model gradually learns task-specific rules from instructions and experience, and that bottom-up processing is used whenever possible. In a model of learning perfect time-sharing in dual tasks (Schumacher et al., 2001), speedup learning and bottom-up activation of instructions can explain parallel behavior. In a model of a complex dynamic task (Carnegie Mellon University Aegis Simulation Program [CMU-ASP], Anderson et al., 2004), parallel behavior is explained by the transition from serially organized instructions to rules that are activated by both top-down (goal-driven) and bottom-up (perceptually driven) factors. Parallelism lets the model opportunistically reorder instructions, leading to the gradual emergence of new task strategies.  相似文献   
139.
Differential item functioning (DIF) analyses of the Beck Depression Inventory-II (BDI-II) were conducted on samples of 267 women with breast cancer and 294 women with clinical depression. Patterns of items in which there was significant and nonsignificant DIF were identified using statistical tests and measures of DIF effect size. At the most general level, 15 of 21 BDI-II items were associated with nontrivial DIF suggesting that the item responses of these samples do not reflect the same underlying construct. Factor analyses of the BDI-II using a psychometrically defensible method for item level factor analysis supported the conclusions from the DIF analyses. These findings suggest that researchers and practitioners should apply caution when interpreting self-report depression symptoms in breast cancer patients.  相似文献   
140.
Previous research has shown that an acute, post-training injection of D-cycloserine (DCS) facilitates extinction of conditioned fear in rats; however, the effects of multiple exposures to DCS in this situation are not known. In Experiment 1, rats were conditioned (light-shock pairings) and 24 h later given six extinction (light-alone) trials followed by an injection of DCS (15 mg/kg) or saline. The next day, all rats were tested for light-elicited freezing. In Experiment 2, the effect of DCS on extinction was tested in the same manner, except that rats were pre-exposed to DCS (0, 1, or 5 injections) just prior to conditioning. In Experiment 3, rats received five pre-exposures of DCS but conditioning occurred either 2 or 28 days after the last pre-exposure. The results showed that DCS facilitated extinction of conditioned freezing to the light CS when no drug pre-exposure had occurred, but pre-exposure to DCS just prior to conditioning disrupted the facilitation of extinction effect. When 28 days were interposed between pre-exposure and conditioning, the facilitatory effects of DCS on extinction were restored. These findings suggest that DCS has significant clinical value but that behavioral desensitization may occur with multiple exposures; however, desensitization is not permanent and is reduced by the passage of time.  相似文献   
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