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211.
Computational models of cognitive aging propose that age-related decrements in cognitive performance, including short-term memory (STM), result from less distinct stimulus representations. When applied to visual STM, these models predict higher discriminal dispersion (L. L. Thurstone, 1927, Psychophysical analysis, The American Journal of Psychology, 38, 368-389.) in older adults than in younger adults. To test this prediction, we used a change-detection paradigm for visuospatial locations, with different levels of cognitive load (one, three, or five items) and retention interval (100 or 1,000 ms). Adult age differences were not reliable at Load 1, but were substantial at Loads 3 and 5. Effects of retention time did not differ across age groups, suggesting that age-related differences originated mainly from early processing stages. Applying a mixture model to the data revealed age-related increases in discriminal dispersion and decreases in asymptotic discrimination performance (indexing STM capacity). We concluded that age-related declines in discriminal dispersion, in addition to increasing capacity limitations, impair visual STM performance with advancing adult age. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
212.

Purpose  

This study investigated whether meeting electronically first using computer-mediated communication (CMC) before meeting face-to-face (FTF) increases the inclusion of a female group member in a predominantly male project team.  相似文献   
213.
The BRIEF-P is one of the most used instruments to measure Executive Function (EF). This report is aimed at showing the psychometric properties of the Catalan version of it. To do this, a random cluster sampling was carried out in Osona (Catalonia), recruiting 417 teachers and 408 parents of children aged 3 to 6 years. As with the original instrument, results show that reliability is excellent and that girls have a better EF than boys in the following areas: Working Memory, Plan/Organize, and Inhibit. Since in some areas Catalonia's preschool children show EF values slightly better than those of the reference sample, a new scale for using it in this population is provided.  相似文献   
214.
In this paper we present a new framework of idealization in biology. We characterize idealizations as a network of counterfactual and hypothetical conditionals that can exhibit different ??degrees of contingency??. We use this idea to say that, in departing more or less from the actual world, idealizations can serve numerous epistemic, methodological or heuristic purposes within scientific research. We defend that, in part, this structure explains why idealizations, despite being deformations of reality, are so successful in scientific practice. For illustrative purposes, we provide an example from population genetics, the Wright-Fisher Model.  相似文献   
215.
Research on the psychometric characteristics, including factor structure, of measures assessing emotional intelligence improve our understanding of the manifest and latent dimensions of the construct. The factor structure of the Bar-On Emotional Quotient Inventory (Bar-On, 1997), despite the popularity of the measure, has been the subject of only a few studies, and there are no data available at all on its 30-item version. The aim of our study was the structural analysis of the Bar-On Emotional Quotient Inventory, Youth Version, Short Form (Bar-On & Parker, 2000). During the multiple-step statistical analysis, confirmatory and exploratory factor analyses and a combined method of these were executed on a sample of 2,380 adolescents (mean age: 17 years, 47.9 % male). The results confirmed the original 5-factor structure (Intrapersonal Emotional Quotient, Interpersonal Emotional Quotient, Stress Management, Adaptability, and Positive Impression). However, only 24 of the original 30 items could be considered as belonging to the scales. Elimination of 6 items resulted in a clearer and more coherent factorial structure, which makes the measure an adequate tool for the assessment of the emotional intelligence of adolescents and young adults in surveys of large-scale samples.  相似文献   
216.
A 2-phase study was conducted to develop a culturally informed measure of psychosocial stress for adolescents: the Hispanic Stress Inventory--Adolescent Version (HSI-A). Phase 1 involved item development through the collection of open-ended focus group interview data (n = 170) from a heterogeneous sample of Hispanic youths residing in the southwest and northeast United States. In Phase 2, we examined the psychometric properties of the HSI-A (n = 1,651), which involved the use of factor analytic procedures to determine the underlying scale structure of the HSI-A for foreign-born and U.S.-born participants in an aggregated analytic approach. An 8-factor solution was established, with factors that include Family Economic Stress, Acculturation-Gap Stress, Culture and Educational Stress, Immigration-Related Stress, Discrimination Stress, Family Immigration Stress, Community and Gang-Related Stress, and Family and Drug-Related Stress. Concurrent, related validity estimates were calculated to determine relations between HSI-A and other measures of child psychopathology and behavioral and emotional disturbances. HSI-A total stress appraisal scores were significantly correlated with both the Children's Depression Inventory and the Youth Self Report (p < .001). Reliability estimates for the HSI-A were conducted, and they yielded high reliability coefficients for most factor subscales, with the HSI-A total stress appraisal score reliability alpha at .92.  相似文献   
217.
Diagnostic tests are available to detect several mutations related to adult-onset, autosomal dominant, neurodegenerative diseases. We aimed to describe our experience in a presymptomatic testing program run by the Brazilian Public Health System from 1999 to 2009. A total of 184 individuals were eligible for presymptomatic testing due to a risk for spinocerebellar ataxia (SCA) - SCA3 (80%), Huntington’s disease (11.9%), familial amyloidotic neuropathy (4.3%), SCA1, SCA2, SCA6, or SCA7. Most were women (70%), married (54%), and had children prior to presymptomatic testing (67%). Their mean age at entrance was 34 (SD = 11 years). Educational level was above the average Brazilian standard. After receipt of genetic counseling, 100 individuals (54%) decided to undergo testing; of these, 51 were carriers. Since no individual returned for post-test psychological evaluation, we conducted a subsequent survey, unrelated to test disclosures. We contacted 57 individuals of whom 31 agreed to participate (24 had been tested, 7 had not). Several ascertainment concerns relating to these numerous losses prevented us from generalizing our results from this second survey. We concluded that: decision-making regarding presymptomatic testing seems to be genuinely autonomous, since after genetic counseling half the individuals who asked for presymptomatic testing decided in favor and half decided against it; general characteristics of Brazilians who sought presymptomatic testing were similar to many European samples studied previously; and individuals at risk for SCA3 may be at greater risk of depression. Although no clear-cut reason emerged for rejection of follow-up psychological sessions after presymptomatic testing, this finding suggests adjustments to our presymptomatic testing program are necessary.  相似文献   
218.
Notwithstanding several neurotransmission systems are frequently related to memory formation; forgetting process and neurotransmission systems or their transporters; the role of γ-aminobutyric acid (GAT1), glutamate (EACC1), dopamine (DAT) and serotonin (SERT) is poorly understood. Hence, in this paper western-blot analysis was used to evaluate expression of GAT1, EAAC1, DAT and SERT during forgetting in trained and untrained rats treated with the selective serotonin transporter inhibitor fluoxetine, the amnesic drug d-methamphetamine (METH) and fluoxetine plus METH. Transporters expression was determined in the hippocampus (HIP), prefrontal cortex (PFC) and striatum (STR). Results indicated that forgetting of Pavlovian/instrumental autoshaping was associated to up-regulation of GAT1 (PFC and HIP) and DAT (PFC) while SERT (HIP) was down-regulated; no-changes were observed in striatum. Methamphetamine administration did not affect forgetting at 216 h post-training but up-regulated hippocampal DAT and EACC, prefrontal cortex DAT and striatal GAT1 or EACC1. Fluoxetine alone prevented forgetting, which was associated to striatal GAT1 and hippocampal DAT up-regulation, but prefrontal cortex GAT1 down-regulation. Fluoxetine plus METH administration was also able to prevent forgetting, which was associated to hippocampal DAT, prefrontal cortex SERT and striatal GAT1, DAT or SERT up-regulation, but prefrontal cortex GAT1 down-regulation. Together these data show that forgetting provokes primarily hippocampal and prefrontal cortex transporters changes; forgetting represent a behavioral process hardly modifiable and its prevention could causes different transporters expression patterns.  相似文献   
219.
This article proposes a new approach to factor analysis and structural equation modeling using Bayesian analysis. The new approach replaces parameter specifications of exact zeros with approximate zeros based on informative, small-variance priors. It is argued that this produces an analysis that better reflects substantive theories. The proposed Bayesian approach is particularly beneficial in applications where parameters are added to a conventional model such that a nonidentified model is obtained if maximum-likelihood estimation is applied. This approach is useful for measurement aspects of latent variable modeling, such as with confirmatory factor analysis, and the measurement part of structural equation modeling. Two application areas are studied, cross-loadings and residual correlations in confirmatory factor analysis. An example using a full structural equation model is also presented, showing an efficient way to find model misspecification. The approach encompasses 3 elements: model testing using posterior predictive checking, model estimation, and model modification. Monte Carlo simulations and real data are analyzed using Mplus. The real-data analyses use data from Holzinger and Swineford's (1939) classic mental abilities study, Big Five personality factor data from a British survey, and science achievement data from the National Educational Longitudinal Study of 1988. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
220.
This rejoinder discusses the general comments on how to use Bayesian structural equation modeling (BSEM) wisely and how to get more people better trained in using Bayesian methods. Responses to specific comments cover how to handle sign switching, nonconvergence and nonidentification, and prior choices in latent variable models. Two new applications are included. The first one revisits the Kaplan (2009) science model by considering priors on primary parameters. The second one applies BSEM to the bifactor model that was hypothesized in the original Holzinger and Swineford (1939) study. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
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